AN EVALUATION OF ENVIRONMENTAL, BIOLOGICAL AND HEALTH

 DATA FROM THE ISLAND OF VIEQUES, PUERTO RICO 

RELEASE DATE: DECEMBER 8, 2011 

COMMENT PERIOD: 90 DAYS FROM RELEASE DATE 

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
 

Agency for Toxic Substances and Disease Registry 

Division of Health Assessment and Consultation 

Atlanta, Georgia 30333 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques (Public 

Comment) December 2011

This information is distributed solely for the purpose of predissemination public comment under 

applicable information quality guidelines. It has not been formally disseminated by the Agency for Toxic 

Substances and Disease Registry. It does not represent, and should not be construed as representing, any 

agency determination or policy.

This document is presented in English and Spanish for the convenience of the reader. We have made 

every effort to ensure the translation is accurate. Readers should be aware, however, that the English 

version is the official version of the text. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | iii

CONTENTS

Executive Summary......................................................................................................................................vii

1. Introduction ............................................................................................................................................. 1

2. Consumption of Fish from Reefs off the Vieques Coast ........................................................................ 17

3. Biomonitoring......................................................................................................................................... 57

4. Health Outcome Data............................................................................................................................. 99

5. Local Produce and Livestock Pathway.................................................................................................. 109

6. Air Pathway .......................................................................................................................................... 123

7. Soil Pathway ......................................................................................................................................... 137

8. Drinking Water Pathway ...................................................................................................................... 151

9. Conclusions and Recommendations.................................................................................................... 161

Appendix A— Study Summaries................................................................................................................A-1

Appendix B— Summaries of Previous ATSDR Documents ........................................................................B-1

Appendix C— Peer Review Comments and ATSDR Responses..................................................................C-1

FIGURES AND TABLES

Figure 1-1. Puerto Rico and Vieques Island .................................................................................................. 2

Figure 1-2. Vieques land use areas............................................................................................................... 3

Figure 1-3. Topographic map of Vieques showing directions of water flow. ............................................... 4

Table 2-1. The type of fish that the 51 respondents ate as reported by Dr. Doris Caro in her survey of 

Viequenses. ............................................................................................................................................ 24

Table 2-2. Average fish-mercury levels from fish markets in northern Vieques, southern Vieques 

(Esperanza), and Parguera, Puerto Rico (Caro 2000)............................................................................. 25

Table 2-3. Average fish-mercury levels: Vieques........................................................................................ 27

Table 2-4. Fish and shellfish collected by ATSDR........................................................................................ 29

Figure 2-1. ATSDR fish and shellfish sample locations................................................................................ 31

Table 2-5. Average total mercury in ATSDR-collected fish and shellfish .................................................... 34

Table 2-6. 50th, 95th, and 99th fish portion size for women and girls of various ages. ................................ 38

Figure 2A-1. Total mercury in fish by family ............................................................................................... 48

Table C1 from U.S.EPA’s report (USEPA 2001) for locations 1 through 6................................................... 51
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page iv

Figures 2A-2a and 2A-2b. Weight (in oz) vs. mercury concentration (ppm) .............................................. 52

Table 2A-1. Estimated mercury dose for women and children of various body weights from eating 

Vieques reef fish..................................................................................................................................... 55

Table 3-1. Vieques human biomonitoring studies...................................................................................... 60

Table 3A-1. Vieques human biomonitoring studies.................................................................................... 68

Table 3A-2. PRDOH Phase 1 results of heavy metal analysis of Vieques residents.................................... 71

Table 9 from Heavy Metal Prevalence Study, Vieques, 2004..................................................................... 78

Table 3A-3. PRDOH biomonitoring study Phase 2 biomonitoring results for 10 persons.......................... 80

Table 3A-4. Mercury hair results in women published by Dr. Ortiz Roque in 2004. .................................. 84

Table 3A-5. Results of metal analysis of hair samples collected from Viequenses from January 2000 to 

July 2001................................................................................................................................................. 85

Table 3A-6. Viequense women and children mercury hair analysis compared with United States........... 86

Table 3A-7. Summary of hair analysis of 30 samples as reported in Dr. Colón de Jorge’s unpublished 

(Colón de Jorge undated)....................................................................................................................... 90

Table 3A-8. Summary of the results of feces analysis as reported in Dr. Colón de Jorge unpublished 

manuscript (Colón de Jorge undated).................................................................................................... 93

Table 3B-1. FourthNational Report on Human Exposure to Environmental Chemicals: urine and blood 

levels toxicity.......................................................................................................................................... 96

Table 4-1. Viequenses-reported health conditions .................................................................................. 103

Table 4-2. Summary of Statistically Significant Standardized Incidence Ratios for Cancer...................... 106

Table 4-3. Summary of Statistically Significant Standardized Mortality Ratios for Cancer ...................... 106

Table 5-1. Exposure dose for pigeon pea fruit (Díaz and Massol Deyá 2003 data).................................. 115

Table 6-1. Average annual concentrations of PM10 and metals: Vieques and Fajardo, PR..................... 131

Figure 6-1b. 2005 Wind rose from San Juan LM Airport. ......................................................................... 132

Figure 6-1a. 2005 Wind rose from Camp Garcia, Isla Vieques. ................................................................ 132

Figure 6-1c. 2005 Wind rose from Roosevelt Roads NAS. ........................................................................ 132

Table 7-1. Direct soil exposure pathways to people on Vieques.............................................................. 139

Table A-1. Radiation sampling in Vieques, 2001........................................................................................A-3

Table A-2. Vieques LIA radiation sampling, 1999–2000 ............................................................................A-6

Table A-3. Water samples from LIA lagoons..............................................................................................A-8

Table A-4. Sediment samples from Gato and Anones Lagoons...............................................................A-11
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page v

Table A-5. LIA vegetation sample results.................................................................................................A-14

Table A-6. Vegetation samples ................................................................................................................A-19

Table A-7. Heavy metal levels in vegetation and health guideline from 1999 study ..............................A-26

Table A-8. Heavy metals in pineapple and soil ........................................................................................A-28

Table A-9. Metals detected in goat hair ..................................................................................................A-30

Table A-10. Metals detected in fiddler crabs...........................................................................................A-35

Table A-11. Heavy metals in market fish .................................................................................................A-38

Table A-12. Sampling results of marine coastal waters...........................................................................A-42

Table A-13. NSWC water sample results .................................................................................................A-48

Table A-14. NSWC soil sample results .....................................................................................................A-48

Table A-15. Results of metal analysis of hair samples collected from Viequenses from January 2000 to 

July 2001..............................................................................................................................................A-55

Table A-16. Mercury hair results in women published by Dr. Ortiz Roque in 2004 ................................A-57
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page vi
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page vii

Scope of Review 

ATSDR recognizes that Viequenses1are concerned about the health of everyone who lives on their 

island. ATSDR further recognizes that Viequenses are concerned about whether past military exercises2

on Vieques might have contributed to health conditions some on the island have reported.

ATSDR wants to be responsive to those concerns. We have worked to ensure that this analysis of 

Viequense environmental data is thorough; that it considers all readily available investigations and 

research, especially research completed since release of our 2001–2003 public health assessments 

(PHA).3Simply stated, this report’s nine chapters endeavor 1) to assess critically all of the available 

exposure and health information relevant to Viequense public health issues, 2) to draw conclusions—

albeit often with some degree of uncertainty—and 3) to make recommendations for environmental and 

public health agencies as well as for scientific researchers that will assist in reducing that uncertainty. 

The circumstances on Vieques typify many of the difficulties faced by the public and by public health 

officials when responding to concerns about the effects of hazardous substances. Although numerous 

questions arise regarding exposures and people’s health, the means are limited to answer such 

questions definitively. When reaching conclusions about hazardous waste and public health, some 

degree of uncertainty will always remain. Thus in this evaluation, ATSDR identifies the available data as 

well as the data gaps.

This report’s principal focus is to review and update environmental data on Vieques air, water, soil, 

seafood, and locally grown foods. In addition, this report adds human biomonitoring and health 

outcome data. It begins with a review and update of ATSDR’s 2003 Fish PHA data on consumption of fish 

caught off the Vieques coast. Next are two chapters on human biomonitoring data and health outcome 

data. These are the chapters whose subject matter was not included in previous ATSDR reports on 

Vieques. At the end of each chapter, we provide conclusions, recommendations, and references specific 

to that chapter. Four chapters are dedicated to examination of exposure pathways from food, air, soil, 

and water. Chapter 9 summarizes all the conclusions and recommendations from each chapter. 

The public health question in the chapters on food, air, soil, and water is whether residents were or are 

exposed to bombing-related contaminants and whether there were or are any public health 

 

1

Throughout this document, the Spanish noun form “Viequenses” refers to the residents of Vieques, and the 

adjectival form “Viequense” refers to Viequenses and Vieques.

2

The term “military exercises” subsumes all forms of naval, Marine, and other military service operations—

including aerial bomb and naval gunfire practice—on and in the vicinity of Vieques. 

3

A public health assessment (PHA) is an ATSDR document that examines hazardous substances, health outcomes, 

and community concerns at a hazardous waste site to determine whether people could be harmed from coming 

into contact with those substances. The PHA also lists actions that need to be taken to protect public health.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page viii

consequences. The chapter on seafood consumption focused on mercury in seafood because Puerto 

Rican scientists and Viequenses raised that as a concern. Mercury in seafood is not from bombingrelated activities. 

The public health question addressed in the biomonitoring and health outcome chapters is different. We 

could not use these data to assess whether bombing-related contaminants are present in Viequenses or 

are causing morbidity or mortality. The purpose of the biomonitoring chapter is to identify whether 

excessive exposure to metals is occurring in Vieques residents and whether there is a risk of harmful 

effects from metal body burdens. The purpose of the health outcome chapter is to assess the overall 

health status of the Viequenses population. Finally, the report includes three appendices. Appendix A 

summarizes the studies reviewed previously by ATSDR or for this report. Appendix B contains summaries 

of ATSDR’s previous documents evaluating Vieques-related environmental data, as well as summaries of 

two ATSDR-funded panel reviews: heart echocardiograms and elemental hair analysis. Appendix C 

contains the peer review comments received and ATSDR responses to those comments.

Background

Isla de Vieques, or Vieques Island, is a 55-square mile tract of land 7 miles off the Commonwealth of 

Puerto Rico’s east coast. Approximately 10,000 persons live in the central 7,000 acres or about 20% of 

the island, mostly in the towns of Isabel Segunda and Esperanza. 

In 1941, as the United States entered World War II, the U.S. Navy began to acquire Vieques property by 

condemnation of private lands. By 1950, the Navy owned the island’s entire eastern and western 

portions. With its wide beaches, shallow approaches, and warm water temperatures, as well as its 

distance from commercial air and shipping lanes, the Navy believed that Vieques was not only ideal for 

naval and Marine warfare training, it was one of the few locations in the Western Hemisphere that met 

all the Navy’s requirements.

The Navy’s Atlantic Fleet Weapons Training Facility (AFWTF) established its so-called Inner Range on 

Vieques, comprising the Eastern Maneuver Area (EMA), and the Live Impact Area (LIA) (see Figure 1-2). 

Marines conducted live-fire exercises in the EMA. Aerial explosive-ordnance and naval gunfire practice 

were limited to the 900-acre LIA, on the island’s easternmost end. Camp Garcia,4the principal Marine 

Corps encampment on Vieques, was also within the EMA’s southern section. 

For decades—particularly after the mid-1970s—ships and aircraft fired, launched, and dropped live 

bullets, artillery rounds, rockets, missiles, and bombs into the LIA. In the years following World War II, 

Viequenses, other Puerto Ricans, scientists, and activists increasingly opposed the Navy’s activities on 

Vieques, contending that those activities deprived many residents of their livelihood (primarily fishing), 

exposed them to injury and, because of chemicals in the explosives, to long-term illness. 

 

4

Named for Puerto Rican native and Marine PFC Fernando Garcia, a Korean War Medal of Honor recipient. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page ix

Opposition increased after April 1999, when an F-18 pilot mistook an observation tower outside the LIA 

for a target. The exploding bomb killed the civilian observer inside the tower and prompted protestors 

to occupy the LIA. All live-fire exercises ceased. After protracted negotiations between the federal 

government and the Commonwealth of Puerto Rico, in early 2003 then-President George W. Bush 

ordered cessation of all military activities on Vieques. Former Navy properties on the eastern and 

western ends of the island, now mostly under U.S. Fish and Wildlife Service (FWS) jurisdiction, are 

national wildlife refuges. In August 2005, the U.S. Environmental Protection Agency (USEPA) added sites 

in the former AFWTF Inner Range to the National Priorities List, making the area subject to federally 

supervised remediation, which continues today. 

Site investigations and environmental assessments began while the Navy still operated on Vieques. After 

the Navy’s departure, a thorough, in-depth evaluation of the current and long-term human health risks 

posed by exploded and unexploded ordnance was initiated.

5

The Navy also looked at the risks military 

exercises generally might pose in Viequense air, water, biota, and in Viequenses themselves. The latest 

of these evaluations is ATSDR’s review of environmental data that began in 2009. This report describes 

and discusses the results of our review. In addition, ATSDR examines some biomonitoring studies and 

health outcome data not available in our previous investigations.

Previous Site Investigations and Assessments

From 2001 to 2003, ATSDR released four Vieques-related PHAs. To investigate possible exposure to 

chemicals emanating from exploded and unexploded ordnance, each PHA assessed a specific exposure 

pathway: seafood (e.g., fish, shellfish, and land crabs), drinking water, air, and soil. After analyzing data 

and after extensive modeling, each PHA concluded that with one specific exception involving a single 

local well, contaminants in the evaluated pathways were not at levels expected to cause health effects. 

But these PHAs did not evaluate the risk of physical injury from unexploded ordnance or consider 

cumulative effects of exposure to multiple contaminants through multiple pathways. Unfortunately, 

current science does not adequately support a robust analysis of multiple chemical exposures and their 

interactions. Debate continues in the scientific community about how best to evaluate exposure to a

chemical mixture both from a single pathway and from multiple, combined pathways. In addition, 

estimating combined doses from multiple pathways on Vieques is hampered by a lack of knowledge of 

the levels of chemicals residents are exposed to through various pathways (e.g., eating seafood, 

ingesting soil, drinking water, and breathing air).

Viequenses and other Puerto Ricans—together with some scientists, elected officials, and citizen 

groups—disagreed with ATSDR’s findings. They believed the Navy’s decades-long island presence left 

behind residual environmental hazards that directly and indirectly affected Viequenses’ health. 

Scientists in Puerto Rico, for example, produced heart and hair studies that challenged ATSDR’s findings. 

For this current site review, ATSDR not only revisited available data used in the previous ATSDR 

 

5

Throughout this document, “exploded or unexploded ordnance” refers to naval gunfire projectiles, aerial bombs, 

and projectiles from other weapons fired, launched, or dropped primarily into the Vieques Live Impact Area (LIA).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page x

reports—and revisited Vieques itself—but also identified new environmental, biomonitoring, and health 

outcome data.6In November of 2009, ATSDR hosted a meeting in Atlanta in which interested scientists 

discussed available scientific data concerning Vieques. The scientists suggested how ATSDR could look at 

the data in additional ways. For example, the group suggested that ATSDR reconsider exposure 

scenarios for fish consumption. They also expressed concern about the lack of information about 

potential exposure to contaminants through consumption of locally grown produce. Discussions such as 

these resulted in some new analyses for this report. A summary of the November 2009 meeting is 

available at http://www.atsdr.cdc.gov/sites/vieques/notes_vsc_toc.html.

This Report’s Conclusions and Recommendations

As part of this evaluation, ATSDR reviewed many of its previous conclusions and recommendations and 

identified some new findings. Again, Chapter 9 contains all of this report’s conclusions and 

recommendations according to the topics described in each chapter. Certain conclusions and 

recommendations are highlighted in this Executive Summary.

Conclusions and Recommendations from Environmental Data

Consumption of Fish from Reefs off the Vieques Coast

 ATSDR has identified mercury exposure from frequent consumption of marine seafood as a 

potential public health hazard. Mercury is present in most seafood; it is particularly high in some 

fish species and low in other species. Due to mercury, children born to women who eat fish daily

from waters surrounding Vieques are at increased risk of language, attention, and memory 

deficits, and to a lesser extent visual/spatial and motor function deficits. Children who 

frequently eat the same fish that their mothers eat are also at risk of similar harmful effects. 

That said, we could find no relationship between mercury in fish and military operations on 

Vieques. A more plausible explanation for the mercury levels found in fish is that they resulted 

from the global reservoir of mercury circulating through the environment.

 Due to the many nutritional benefits, women and young children in particular should include in 

their diets fish or shellfish that are low in mercury. Fish and shellfish are a part of a healthy diet. 

They contain high-quality protein, omega-3 fatty acids, other essential nutrients, and are low in 

saturated fat. A well-balanced diet that includes a variety of fish and shellfish can contribute to 

heart health and children's proper growth and development.

 Statistical analysis showed that some fish and shellfish had higher levels of some metals and 

lower levels of other metals—iron, aluminum, copper, zinc, arsenic, barium, potassium and 

selenium were all slightly higher. These metals are found in bombs and metal ships, suggesting 

possible localized contamination. But the levels were only slightly higher and the difference was 

only statistically significant when compared with a few other locations.

 

6

In this regard, note that the Navy is still involved in remedial activities on Vieques and these activities should be 

conducted in a way that ensures public health is protected from contaminant exposure.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page xi

 ATSDR recommends the following for consideration by environmental and public health 

agencies and scientists:

o People who frequently consume marine seafood should follow available fish advisories and 

fishing restrictions in Vieques. Maintain the fishing restrictions in the waters adjacent to the 

LIA.

o Conduct a survey of Vieques residents to determine the types, frequency, and quantity of 

fish consumed.

o Conduct additional risk assessments and statistical analyses using new information gathered 

from the previously recommended fish consumption survey.

o Should the proposed survey and statistical analysis not provide sufficient public health 

information, collect and analyze additional fish samples from Vieques.

o Collect sufficient fish samples to allow analysis by species and by location.

Biomonitoring

The data from biomonitoring studies in Vieques showed elevated levels of some metals in 

residents’ blood, urine, hair, or feces. While cigarette use, seafood consumption, or hair dyes 

might explain some of these elevated levels in their study, the Puerto Rico Department of Health 

(PRDOH) manuscript reported they do not explain all. Because the source of these metals could 

not be identified, the biomonitoring results do not permit any conclusions about whether these 

elevated levels resulted from exposure to military exercise-related contaminants.

Viequenses may be exposed to mercury in fish and cadmium in pigeon peas. These exposures 

may warrant additional environmental investigations , such as sampling locally grown produce 

for cadmium and gathering more information about fish consumption and possibly mercury in 

fish. The information could be used to decide whether to undertake human testing for mercury 

and cadmium in blood or urine. If other environmental exposures are identified, additional 

human biomonitoring investigations may be considered. More detailed information about 

ATSDR’s recommendations concerning fish and locally grown produce can be found in Chapter 

2, Section 2.3.2 and Chapter 5, Section 5.3.2, respectively.

Although ATSDR is not recommending a comprehensive, systematic biomonitoring effort at this 

time, public health officials could consider a limited and focused human biomonitoring 

investigation following the release of this report. If a biomonitoring investigation is conducted, it 

should include a comparison group from mainland Puerto Rico. If requested, CDC/ATSDR subject 

matter experts will provide technical assistance and support to PRDOH in planning and 

conducting such an investigation.

Viequenses who remain concerned about exposure to mercury, cadmium, other metals, or 

metalloids should consult their healthcare provider to discuss the need for and cost of testing. A 

qualified laboratory should do the testing and analysis.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page xii 

ATSDR Recommends

Developing an educational program 

about mercury in fish that 

incorporates local habits and 

information about Viequenses’ 

seafood consumption. 

Maintaining fishing restrictions near 

the former bombing range. 

That Viequenses talk to their 

healthcare providers about the need 

for biologic testing. 

Additional sampling of locally grown 

foods to better evaluate this 

exposure pathway. 

Sampling surface soil in the island’s

residential areas to address 

uncertainties regarding residential 

soil contamination issues. 

Clean-up activities continue in the 

LIA and other former military 

exercise areas to prevent human 

exposures to harmful contaminants.

 CDC/ATSDR can provide a list of qualified laboratories that can perform the tests. And if 

requested, CDC/ATSDR can provide information to healthcare providers about tests for metals 

in biologic samples. 

Health Outcome Data

Elevated morbidity and mortality in Vieques, coupled with problems accessing health care, paint 

for Viequenses a complex health picture. 

Data indicate elevations in chronic 

disease prevalence, cancer incidence, 

and cancer mortality among the 

Viequense population relative to the rest 

of Puerto Rico. The limitations associated 

with these analyses, particularly the 

methodological concerns discussed in 

this report, introduce considerable 

uncertainty and make interpretation 

difficult. 

Local Produce and Livestock Pathway 

ATSDR evaluated the available data and 

information on contaminants detected in 

locally raised garden produce and in 

livestock. 

The overall data are insufficient to 

quantify human exposures or draw 

health conclusions. Limited sampling 

data suggest cadmium toxicity may be a 

concern for excessive consumption of 

pigeon peas, but not for typical 

consumption rates of pigeon peas. 

A preliminary data evaluation completed for this report has concluded that the level of cadmium 

reported in a few samples of locally grown pigeon peas would not contribute excess dietary 

cadmium to preschool children who eat less than five of the largest (6 ounces) servings per 

week of locally grown pigeon peas. Adults who eat the largest serving sizes (12 ounces) should 

limit intake to 11 servings per week. Typical serving sizes for preschool children (1.5 ounces) do 

not contribute excess cadmium below 20 meals per week and adults who eat a typical serving (3 

ounces) may eat up to 44 meals per week without exceeding recommended cadmium intake 

levels. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page xiii

 The significant uncertainty in the evaluation of cadmium in pigeon peas stresses the need for

further sampling. Preliminary evaluation suggests a potential for uptake of metals from soil into 

food crops. These results warrant further investigation. 

Air

We reviewed the data on airborne contaminants from military exercises at the former Vieques 

Naval Training Facility. This review confirmed our previous findings and indicated that airborne 

contaminants from past military operations were very unlikely to have had health effects on 

Viequenses

Soil

Sufficient data are available to conclude that people who lived on the LIA during the 1999–2000 

protests were not exposed to soil contaminants at levels high enough to cause adverse health 

effects. 

Recent data, and the presence of unexploded ordnance at the LIA, support the need for 

continued, restricted access to the LIA and to other potentially contaminated former military 

exercise areas. Environmental assessment and remediation activities should continue.

In the island’s residential areas, no soil data are adequate to characterize potential exposures 

fully. To address remaining uncertainties about residential soil contamination issues, ATSDR 

recommends surface-soil sampling in the island’s residential areas. 

Drinking Water

 With the possible exception of one private well found to contain harmful nitrate-nitrite levels,

all drinking water supplies in Vieques are acceptable for their current uses. ATSDR recommends 

no one drink from the one private well until further testing confirms its water is safe. 

Ongoing monitoring of the current pipeline-source water is required to ensure the supply meets 

drinking water standards. Repeating previous sampling of storage tanks, residential taps, and 

wells still in use would address any remaining uncertainty.

Peer Review and Public Comment

Scientists from the Commonwealth of Puerto Rico and from the United States reviewed the Vieques 

Summary Report. Appendix C of this report contains their comments and ATSDR’s responses. The next 

step in the report process is for ATSDR to release the report for public comment. Members of the public 

will then have an opportunity to review the report and to comment. ATSDR will review all such

comments and, if appropriate, will revise the text before releasing this report as a final document. 

During the public comment period for this report, CDC/ATSDR will consult with environmental and 

public health agencies to determine how our recommendations may be implemented, by whom, and 

timelines for implementation. The final report will include conclusions and recommendations that will 

provide guidance for future work on Vieques. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page xiv
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 1

1. Introduction

1.1. Island Overview .......................................................................................................................... 2

1.2. Vieques and the U.S. Navy.......................................................................................................... 2

1.3. Chemicals in Munitions and Detonation Byproducts................................................................. 5

1.3.1. Organic Compounds in Munitions and Detonation Byproducts ..................................... 6

1.3.2. Inorganic Compounds in Munitions and Detonation Byproducts................................... 7

1.3.3. What Bomb-related Constituents Were Found in Vieques............................................. 8

1.3.4. Linking Contaminants in Vieques with Human Exposure Pathways ............................. 11

1.4. The Vieques Civilian Population ............................................................................................... 12

1.5. ATSDR’s Evaluation of Vieques................................................................................................ 12

1.6. The Report................................................................................................................................ 13

1.7. References................................................................................................................................ 14
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page 2 

1.1. Island Overview 

Vieques is the Commonwealth of Puerto Rico’s 

largest offshore island (see Figure 1-1). Twenty 

miles long and 4.5 miles wide at its widest point, 

Vieques comprises some 33,000 acres, or 51 

square miles. Puerto Rico, the easternmost island 

in the Greater Antilles chain, is approximately 7 

miles west of Vieques. The U.S. Virgin Islands, including St. Thomas, St. John, and St. Croix, are 20 miles 

or more northeast and southeast. Drinking water for the island is supplied by pipeline from the main 

island of Puerto Rico—Vieques groundwater is not used for drinking purposes. Figure 1-3 contains a 

topographic map showing groundwater flow on the island. 

1.2. Vieques and the U.S. Navy 

From 1941 until 2003, the U.S. Navy owned much of Vieques; residents were largely confined to areas 

slightly west of the of the island’s center (see Figure 1-2). On the island’s eastern half, the Navy’s 

Atlantic Fleet Weapons Training Facility (AFWTF) administered the Eastern Maneuver Area (EMA) and, 

at the island’s easternmost end, the Live Impact Area (LIA). Major training was generally restricted to 

two 90-day periods each year. Operating from Camp Garcia in the EMA’s southern section, U.S. Marines 

rehearsed amphibious assaults on Vieques beaches, maneuvered inland with armored and other 

vehicles, and generally worked with naval task forces to ensure combat-readiness before embarking on 

major deployments. 

Figure 1-1. Puerto Rico and Vieques Island
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page 3 

Over and off the Vieques east coast, the Navy used the LIA for naval gunfire training. Arrows in Figure 1-

3 below show directions of surface water, stream, and shallow for air-to-ground, explosive-ordnance 

exercises (CH2MHILL and Baker 1999). After the Culebra Island range closed in the mid-1970s (see 

Figure 1-1), air-to ground and ship-to-shore training activities increased in the LIA. Major exercises were 

usually in the spring and fall, but smaller exercises occurred throughout the year (IT 2000). Unexploded 

ordnance (UXO), that is, bombs or explosive ordnance and other waste military munitions, were treated 

and detonated in the LIA. Today, when UXO are identified, they are transported to an authorized area 

and detonated with a remote control charge. UXO that cannot be transported safely to the open 

burning/open detonation area are detonated on site in accordance with prescribed procedures. 

NASD – Naval Ammunition Support 

Detachment

EMA -- Eastern Maneuver Area 

AFWTF – Atlantic Fleet Weapons Training 

Facility 

LIA – Live Impact Area

Figure 1-2. Vieques land use areas

Former Navy Property
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page 4 

Figure 1-3. Topographic map of Vieques showing directions of water flow. 

Arrows show directions of surface water, stream, and shallow groundwater flow. Waterborne contaminants 

cannot flow from LIA to residential area. 

The Navy is still involved in remedial activities on Vieques. These activities should be conducted in a way 

that ensures public health is protected from exposure to contaminants. In 2001, the Navy transferred 

ownership of approximately 7,500 acres of land on the west end of the island to the municipality of 

Vieques, the Puerto Rico Conservation Trust, and the U.S. Fish and Wildlife Service (FWS) but retained 

about 100 acres of the former Naval Ammunition Support Detachment (NASD) lands for radar and 

communication facilities (Navy 2001). Some NASD areas were leased to local farmers for cattle grazing 

and other agricultural purposes (USEPA 2004). On May 1, 2003, after civilian protests and negotiations 

between the federal and Puerto Rican governments, all military operations ceased on and around the 

island. The Navy transferred its remaining 14,500-acre property on the eastern end of the island to the 

FWS (USEPA 2004). Lands on the eastern and western ends of the island are now a national wildlife 

refuge. The Navy has initiated site investigations and cleanup actions pursuant to the Resource 

Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation, 

and Liability Act (CERCLA), sometimes referred to as the Superfund Act. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page 5 

1.3. Chemicals in Munitions and Detonation Byproducts 

During the peer review process for this report, several peer reviewers pointed out that the report failed 

to discuss any link between historical, military activity-related contaminates that might have entered the 

Viequense environment and any resultant human exposure from those contaminants. Previous PHAs 

looked at this issue; their findings are summarized in the following statements. 

 ATSDR’s Water PHA acknowledged that very low levels of RDX, tetryl, ammonia, and nitrate plus 

nitrite might have been present in drinking water samples taken by the Navy in 1978, but also 

expressed doubts about the validity of these data. Additionally, water samples from the 

Esperanza aquifer contained metals, high levels of total dissolved solids (TDS), and high salt. Two 

of the metals found in the Sun Bay wells (iron and manganese) and the TDS in all wells were 

above their secondary maximum contaminant levels (SMCL) established by U.S.EPA as a national 

secondary drinking water regulation. SMCLs are established only as guidelines to assist public 

water systems in managing their drinking water for aesthetic considerations, such as taste, 

color, and odor. TDS—including iron, manganese, and sodium—are commonly found in 

groundwater. The presence of these metals was considered directly related to the high levels of 

TDS in the water and probably reflected the natural geology of the island, given that the igneous 

and volcanic rocks that make up the bedrock of Vieques are a common source of iron and 

manganese (ATSDR 2001). 

 ATSDR’s Soil PHA concluded that the soils of the LIA appeared to be influenced by Navy 

activities. The concentrations of heavy metals found at the LIA were 1.4 to 2.9 times higher than 

background concentrations collected from the west end of the island. Current soil data from the 

residential area of Vieques were not available, therefore, ATSDR conducted a very conservative 

health evaluation that included concentrations of metals detected in areas where access was 

restricted (i.e., land previously owned by the Navy, including the LIA) (ATSDR 2003a). 

 ATSDR’s Air PHA stated the Navy's past military exercises at Vieques released contaminants to 

the air, including dusts, chemical byproducts of explosions, and metals. Using particulate 

ambient air monitoring data from the residential areas of the island, the PHA concluded that 

wind-blown dust from the LIA was not a health hazard on days without bombing exercises and 

that the Navy's past military training exercises with practice bombs did not pose a health hazard. 

The modeling analysis of the Air PHA predicted that chemicals emitted from live bombing 

exercises dispersed to extremely low levels over the 7.9 miles that separate the emissions 

source (the LIA) and the residential area of Vieques. For a majority of the contaminants 

released, the estimated concentrations in the residential areas are so low that even highly 

sensitive air sampling devices would likely not be able to measure them (ATSDR 2003b). 

 As a part of ATSDR’s Fish and Shellfish PHA, fish and shellfish were analyzed for explosive 

compounds and heavy metals. Some evidence showed that explosive compounds might have 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 6

contaminated the marine environment. HMX and a chemical similar to RDX7 were detected in 

fiddler crabs collected on the LIA. Because the fiddler crabs had not been rinsed before

sampling, whether the explosive residues were present in the fiddler crabs or were due to 

external sand and dirt contamination was unclear. One trunkfish from the fish market was found 

to contain trace amounts of a chemical similar to RDX.

7

Explosive compounds were not detected 

in any of the other 142 edible fish or shellfish samples. Several heavy metals were detected in 

the fish and shellfish. Nevertheless, ATSDR could not confirm whether the metals found in 

Vieques fish and shellfish were related to military activity; seafood tends to accumulate metals 

that are naturally present in the environment (ATSDR 2003c).

The subsections that follow briefly describe 1) the organic and inorganic compounds and elements 

present in munitions and detonations, 2) what is known about these constituents in the Vieques 

environment, and 3) whether these constituents can be linked to human exposure on the island.

1.3.1. Organic Compounds in Munitions and Detonation Byproducts

In Vieques’ eastern region, various branches of the U.S. military used many different ordnance types 

(e.g., firebombs, parachute flares, rockets, inert rockets, machine guns, practice bombs, and live 

explosives) (Young 1978). Organic compounds are typically found in the explosive charge of the military 

ordnance, and not in the casings. The explosive components of bombs varied over the years, but usually 

included some combination of

 2,4,6-trinitrotoluene (TNT), 

 Cyclotrimethylene trinitramine (RDX), 

 Methyl-2,4,6-trinitrophenylnitramine (tetryl), 

 Cyclotetramethylene tetranitramine (HMX), or

 Ammonium picrate (explosive D). 

When ordnance detonates, the organic explosives are rapidly consumed and release large amounts of 

energy. In the process of detonation, the organic explosives are largely—but not completely—

destroyed. Thus, they form other compounds. The scientific understanding of detonation byproducts of 

explosions has advanced over the years. For example, some early Navy publications (Young 1978) listed 

various detonation byproducts anticipated for the types of organic explosives used at Vieques. These 

estimates included the following compounds and compositions: carbon dioxide (35%), nitrogen (27%), 

carbon monoxide (16%), water (8%), ethane (5%), carbon (6%), propane (2%), plus several minor by 

products (e.g., ammonia, hydrogen, hydrogen cyanide, methane, methanol, formaldehyde) formed in 

trace quantities (<1%). These estimates are based on theoretical calculations, not on field-testing of 

actual detonations. 

 

7

The laboratory that conducted the analyses could not confirm a conclusive identification.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 7

Scientists have since developed more sophisticated and rigorous testing procedures for identifying and 

measuring detonation byproducts. “BangBox” studies (e.g., US Army 1992) have been particularly useful 

for directly measuring organic chemicals released following detonations. The BangBox refers to a flexible 

structure in which ordnance is detonated. Because the BangBox is completely enclosed, byproducts 

formed during the detonation do not escape the structure. Air sampling equipment can measure them. 

Scientists have used the BangBox to estimate emission factors for various types of ordnance, many of 

which are similar or identical to those used at Vieques. The BangBox studies have identified more than 

50 organic compounds expected to be emitted to the air in trace quantities as detonation byproducts. In 

addition to the byproducts listed in the previous paragraph, the BangBox studies found the following 

byproducts in greatest quantities (but all were less than 0.1% of the total emissions): sulfur dioxide, 

benzene, naphthalene, acetylene, di-butyl phthalate, and various aromatic compounds. The modeling 

analysis in the Air PHA considered emission rates for every organic byproduct identified in the BangBox 

studies for the types of ordnance most similar to those the Navy used at Vieques.

1.3.2. Inorganic Compounds in Munitions and Detonation Byproducts 

Inorganic compounds in munitions, including metals, are found in the metal bomb casings and 

sometimes in the explosive charge. Both sources of inorganic compounds (primarily metals) are 

reviewed here. 

ATSDR’s Air PHA characterized the composition of ordnance dropped onto the LIA and emitted into the 

air because of the training exercises. The most abundant elements in bomb casings were iron (93%), 

aluminum (5%), copper (2%), manganese (2%), and zinc (0.5%). The percentages shown total more than 

100%—not uncommon when expressing metal content in alloy mixtures (i.e., an upper bound 

concentration is often used when characterizing the composition of individual constituents). Numerous 

other metals were present in bomb casings at concentrations less than 0.02%, including boron, 

chromium, molybdenum, nickel, and titanium (ATSDR 2003b). The predominant metal in explosive 

charges was aluminum, which accounted for as much as 21% of the explosive charge in some live bombs 

(ATSDR 2003b). 

The emission factors for the BangBox studies identified the following five metals as having the highest 

emissions—in decreasing order: copper, zinc, aluminum, calcium, and lead. Eleven other metals were 

detected in these studies, but at lower levels. It should be noted that these studies did not measure 

concentrations of certain metals (e.g., iron, manganese) found in highest concentrations in the bomb 

casings (ATSDR 2003b).

Given the previous review, iron, aluminum, copper, manganese, zinc, and lead are the metals most likely 

to be elevated in LIA soils from military activity, though other metals were also found in bombs. It 

should be noted that all of these metals are also naturally present in the soils and rocks of Vieques

(ATSDR 2003a, Learned 1973, USGS 1997 and 2001).

Because mercury was historically used in certain detonators, mercury has been mentioned as a 

contaminant of concern (Garcia et. al. 2000). Bomb casing composition data originally provided by the 

Navy indicated that casings did not contain mercury, which is consistent with information on Material 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 8

Safety Data Sheets available for steel. The Air PHA indicated that the total annual estimated mercury 

emissions from high explosive ordnance used at the LIA were very low (i.e., less than 1 pound per year). 

Following detonation, the mercury was presumably a trace constituent in the explosive charge and in 

the soil ejected into the air. Therefore, the live ordnance dropped on the LIA does not appear to be a 

significant mercury source in the Vieques environment.

1.3.3. What Bomb-related Constituents Were Found in Vieques

Vieques has seen numerous environmental sampling efforts over the past few decades. This section 

reviews the evidence for ordnance-related constituents in the local environment. Information is first 

presented for explosive compounds, then for metals. 

What follows is a summary of explosive compounds found in various media from Vieques. Because 

explosive compounds do not occur naturally, the presence of these contaminants in environmental 

media point to the past military activities as the most likely source.

 In 2000, surface soil samples collected from the LIA showed rare detections of HMX, RDX, 2-

amino-DNT, and TNT (CH2MHill 2000). 

 In 2003, seawater samples from inside and near a 2000-lb bomb in Bahia del Sur showed 

explosive compounds, but explosives were not detected in samples near the sunken target 

vessel, the former USS Killen (Barton and Porter 2004).

 In 2003, sediment samples collected from within 2 meters of a 2000-lb bomb in Bahia Salina del 

Sur showed TNT. Farther away, the concentration declined to nondetectable. Sediment samples 

collected from the vicinity of the former USS Killen contained no detectable explosive residues 

(Barton and Porter 2004).

 In 2001, fish and shellfish were collected and their tissues analyzed for explosive compounds. No 

explosive residues were detected in fish tissues from any species or sample location, except for 

trunkfish. One trunkfish from the fish market was found to contain trace amounts of a chemical 

similar to RDX. Of the four shellfish species sampled, only fiddler crabs were shown to contain 

the explosive compound HMX. A chemical similar to RDX8 was also detected in fiddler crabs, but 

the level was so low that an accurate determination could not be made. Because the fiddler 

crabs had not been rinsed prior to sampling, it was unclear whether the explosive residues were 

present in the crabs or were due to external sand and dirt contamination (ATSDR 2003c). 

 In 2003, other marine organisms (one damselfish, one feather duster worm, and one sea urchin) 

collected near a 2000-lb bomb in Bahia Salina del Sur showed explosive residues. 1,3,5-

trinitrobenzene was detected in a damselfish sample; TNT was found in a feather duster worm 

and in a sea urchin. Explosive residues were not detected in fish and lobster samples collected 

 

8

The laboratory that conducted the analyses could not confirm a conclusive identification.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 9

near the former USS Killen. One coral sample from the USS Killen area contained detectable TNT 

residues (Barton and Porter 2004).

The previous results show that small amounts of explosive compounds remain in the Vieques terrestrial 

and marine environments. While explosives have been detected in or on some organisms (e.g., feather 

duster worm, sea urchin, fiddler crabs), nearly every fish tissue sample to date has failed to contain 

detectable levels of explosives, with the only exception being a single damselfish tissue sample—a 

species not typically consumed by people—and possibly one trunkfish sample.

The remainder of this section evaluates the presence of munitions-related metals in the Vieques 

environment. Metals were clearly present in the bombs the Navy dropped on the island and into the 

nearby ocean. The metals that landed in the Vieques environment might change chemical form over 

time, but the metals themselves will not decay or decompose. Nevertheless, because many metals occur

naturally in soil and sediment, distinguishing is often difficult between naturally occurring 

concentrations and concentrations that represent human-activity contamination. The text that follows 

considers whether metals in the LIA soils have been found at levels believed above background. 

In 2006, the Navy’s contractor (CH2MHILL) conducted a survey of soil inorganics in east Vieques 

(CH2MHILL 2007). The survey’s goal was to establish background levels within the naval training areas

that could be used to determine whether other soil samples from suspected contaminated areas 

exceeded background levels. In cases where sampling results exceed background ranges, a logical 

inference is that the elevated measurements reflect contributions from past military activities or some 

other manufactured source. For each metal and element in the report, an upper tolerance limit (UTL) 

was developed for the various soil types in east Vieques. The UTL is a statistically derived value, with the 

exact derivation depending on the shape of the distribution of the sampling results (e.g., normal versus 

lognormal). The inference to be drawn from the UTLs is that measured soil concentrations below these 

values are indistinguishable from background concentrations. Not surprisingly, the UTLs were highest for 

the predominant elements in soil, including aluminum (35,000 ppm for all soil types), iron (38,100 -

43,200 ppm, depending on soil type) and magnesium (3,710 - 22,200 ppm, depending on soil type). 

Other elements in soil had UTLs with the following ranges depending on soil type (CH2MHill 2007):

 Arsenic 1.6–9.2 ppm 

 Beryllium 0.27–0.95 ppm

 Cadmium 2.2–2.4 ppm

 Chromium 70–72 ppm

 Cobalt 16–26 ppm

 Copper 53–94 ppm

 Lead 5.4–16 ppm

 Mercury 0.057–0.31 ppm

 Nickel 22–41ppm
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 10

 Vanadium 56–144 ppm

 Zinc 32 ppm for all soil types

To identify metals possibly associated with military exercises, ATSDR compared soil samples collected in 

2000 at the LIA (CH2MHILL 2000) to the above-listed UTLs. For the following metals, at least 30% of the 

measured concentrations exceeded background levels in LIA soils, as characterized by the UTLs. The 

maximum soil concentration for each metal follows: 

 Arsenic 20 ppm

 Beryllium 0.48 ppm

 Chromium 120 ppm

 Cobalt 32 ppm

 Iron 59,000 ppm

 Lead 33 ppm

 Vanadium 220 ppm

 Zinc 180 ppm

Mercury was also considered in this data comparison. Still, the average mercury levels in LIA soils from 

the 2000 dataset was 0.02 ppm and the highest level was 0.086 ppm (CH2MHILL 2000). Only one of 29 

soil samples had a mercury level that could be considered above naturally occurring levels when 

compared with the background UTLs (0.057–0.31 ppm; CH2MHILL 2007). 

In May and October 2007, the National Oceanic and Atmospheric Administration (NOAA) randomly 

collected 78 sediment samples and 35 coral samples from near shore waters and a number of inland 

lagoons (sediments only) on Vieques (Bauer and Kendall 2010). The samples were grouped according to 

adjacent land use. A series of statistical tests were carried out to understand the distribution of the 

chemicals in the sediments. The concentrations of cadmium collected from sediments on and near the 

LIA were significantly higher than in sediments collected from the residential area of the island. The 

concentrations of cadmium were also found significantly higher in coral tissues than in sediments (Bauer 

and Kendall 2010). In addition, sediment concentrations of arsenic, copper, and chromium from the 

inland lagoons at the LIA were, on average, higher than sediment concentrations of these metals found 

in the other inland lagoons sampled elsewhere on Vieques.

In conclusion, soil or sediment concentrations of arsenic, beryllium, cadmium, chromium, cobalt, 

copper, iron, lead, vanadium, and zinc appear above naturally occurring levels in some areas in and 

around the LIA. The presence of these metals above background concentrations could reflect the 

influence of military activity, given the lack of other contamination sources at the LIA. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 11

1.3.4. Linking Contaminants in Vieques with Human Exposure Pathways

ATSDR’s soil PHA evaluated how elevated metals in LIA soils could affect Viequenses. Those living in the 

residential portion of the island do not have direct contact with LIA soils 7 to 8 miles away. Thus,

exposures from any elevated metals in LIA soils cannot affect their health. Specific environmental 

sampling showed that Viequenses who camped on portions of the LIA in 2000–2001 were not exposed 

to metals (or other contaminants) in soil at levels that could harm their health. Similarly, the Air PHA 

concluded that metals in air from military activities could reach residential areas of the island, but not at 

levels that could harm people’s health.

Some migration of contaminants from the soils to the marine environment undoubtedly occurs at 

Vieques, just as weathering of soils naturally occurs in virtually any shoreline setting. Precipitation and 

wind can carry soils from the LIA—and chemicals found in these soils—either directly into marine waters 

or into inland lagoons. And those lagoons have the potential to overflow into the marine environment. 

Environmental decay processes can gradually transform explosives at the LIA into other substances over 

time and thus reduce the potential migration of these chemicals into marine waters. But these chemical 

decay processes do not decompose the metals at the LIA. From an environmental health perspective, 

although migration of contaminants clearly occurs, the rate and amount of chemical migration is more 

important. 

Military activities on Vieques have directly contaminated the marine environment. Some of the 

ordnance previously fired at the LIA landed in the ocean rather than hitting onshore targets. Dr. James 

Porter provided direct evidence of this in photographs depicted during a meeting at ATSDR in November 

2009. Some ordnance found in Vieques waters apparently included unexploded material. While 

explosive organic compounds were found in some marine species, these species are not consumed by 

humans; therefore, the available sampling data indicate that elevated human exposures are not 

occurring. Explosive compounds were not found in the 104 edible fish sampled in 2001 except for a 

chemical similar to RDX in one trunkfish collected from the fish market. 

Two observations suggest that the LIA is not currently the primary source of mercury in fish tissues. 

First, most mercury levels in LIA soils appear to be at naturally occurring levels, with no significant 

spatial variation to suggest that mercury levels are higher at the LIA. Second, ATSDR’s fish sampling 

study did not find unusually elevated tissue concentrations of mercury in Vieques reef fish. A more 

plausible explanation for the mercury levels found in fish is that they resulted from the global reservoir 

of mercury circulating through the environment and not from mercury in some bombs and other 

munitions.

In conclusion, ATSDR evaluated the known environmental data associated with military activities. Our 

evaluation shows that residents living in the central portion of the island did not have direct contact 

with LIA soils at levels that could harm their health. Nor were residents likely to be exposed to 

contaminants in air at levels that could harm their health. While explosive compounds were found in a 

few sampled marine animals, residents did not consume these animals. Therefore, the available data 

indicate that no exposure occurred at levels that would harm health. ATSDR has concluded in this report 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 12

that some residents who frequently ate reef fish were exposed to mercury at levels that could harm a 

developing fetus (see Chapter 2). But this mercury appears associated with global mercury circulating in 

the environment and not with the small amount of mercury in some military ordnance.

1.4. The Vieques Civilian Population

The entire, approximately 10,000-member civilian population of the island—referred to here as 

Viequenses—resides in the island’s central 7,000 acres, mostly in the towns of Isabel Segunda and 

Esperanza. The residential areas are about 7 miles from the LIA. The civilian areas comprise residences 

and agricultural, commercial, and industrial activities. In the past, sugarcane was the principal crop; 

other crops have included coconuts, grains, sweet potatoes, avocados, bananas, and papayas. 

Construction of a General Electric plant in 1969 spurred manufacturing employment in the 1970s and 

released 1,1,1 trichloroethane and small amounts of copper to outdoor air (Bermudez 1998, ATSDR 

2003b). Currently, however, the island is home to only minimal manufacturing activity. Commercial 

fishing fleets are home-ported at Isabel Segunda and Esperanza. Tourism has recently increased in 

economic importance. The 2000 Census indicates that 65% of residents of Vieques live in poverty 

compared with 48% for all of Puerto Rico. The 1990 Census results were similar, with 73% of the 

residents of Vieques living in poverty compared with 59% in all of Puerto Rico.

1.5. ATSDR’s Evaluation of Vieques

The agency’s evaluation of public health concerns on Vieques is the latest in a series of Vieques 

investigations. In 1999, a Vieques resident petitioned ATSDR for a determination of whether the Navy’s 

use of live and inert ordnance resulted in health risks. From 2001 to 2003, ATSDR released four public 

health assessments (PHAs). Each PHA assessed a specific pathway for possible exposure to chemicals: 

seafood (e.g., fish, shellfish, and land crabs), drinking water, air, and soil. Each of these evaluations is 

available at http://www.atsdr.cdc.gov/sites/vieques/publications.html. ATSDR followed the public 

health assessment procedures described in its Public Health Assessment Guidance Manual.9Scientific 

experts peer-reviewed each PHA before its final release. After analyzing data and modeling, each PHA 

concluded that with one specific exception, no health hazard was associated with any pathways 

evaluated. The exception: drinking water from one local well was contaminated with nitrates and not fit 

to drink. 

But some scientists from the University of Puerto Rico, the University of Georgia, and Yale University, as 

well as some Viequenses, disagreed with ATSDR’s findings. Most scientists and residents believed the 

Navy’s decades-long island presence left residual environmental hazards that affected public health on 

Vieques. 

ATSDR has since 2009 gathered more than 75 documents relating to environmental sampling, health 

outcomes, and biomonitoring. Most of these documents were available when ATSDR released the 2001–

2003 public health assessments, but some were completed later.

 

9

Available at: http://www.atsdr.cdc.gov/HAC/PHAManual/index.html. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 13

In August 2009, ATSDR scientists and staff visited Vieques and met with community leaders, Puerto 

Rican scientists, and health officials. From those meetings emerged a commitment to involve local 

experts in ATSDR’s review of Vieques environmental data. ATSDR invited Puerto Rican scientists and 

others who had studied Vieques to meet in Atlanta, Georgia, on November 5–6, 2009. Participants 

engaged in a thorough review of multiple studies, identified the strengths and limitations of many of 

them, and made recommendations for further work. The group suggested that ATSDR reconsider its fish 

consumption exposure scenarios. The group also expressed its concern about potential exposure to 

contaminants through consumption of locally grown produce. Discussions such as these resulted in 

ATSDR performing new analyses for this report. A summary of that meeting is available at

http://www.atsdr.cdc.gov/sites/vieques/notes_vsc_toc.html.

1.6. The Report

ATSDR prepared this report after review of all relevant, available data and related information and after 

the November meeting with invited scientists. We have divided the report into sections on 

environmental data (i.e., air, soil, drinking water, and food consumption), human biomonitoring data, 

and health outcome data. Conclusions and recommendations are made in each chapter and are 

summarized again in Chapter 9. 

ATSDR observes here that the circumstances on Vieques typify many of the difficulties faced by the 

public and by officials concerned about the effects of hazardous substances. Numerous questions arise 

regarding exposures and people’s health, and at times, relatively few measurements are available to 

answer those questions directly. The point is that environmental data are often limited in spatial 

coverage, number, or analytical quality control documentation. Consequently, some degree of 

uncertainty always exists. That means a key part of any review is to consider, before drawing public 

health conclusions, the adequacy of the available data. Note, however, that public health conclusions 

often can be drawn from limited data as long as uncertainties are recognized. ATSDR’s conclusions can 

be reevaluated if new, improved information becomes available. Thus in this evaluation, ATSDR 

identifies the available data as well as the data gaps.

In contrast to environmental data, human biomonitoring can demonstrate how much of a chemical has 

entered the human body. Blood and urine levels of metals and organic chemicals can be useful in the 

comparative sense where potentially exposed groups can be compared to nonexposed or lesserexposed groups to assess whether the target group has unusual or higher than expected exposure. 

Limitations to biomonitoring include the appropriate timing and collection of samples that will affect 

data interpretation. Also, in most situations, biomonitoring provides information about current or 

recent exposures; only in certain situations where a chemical may persist in the body (e.g., lead in bone) 

does biomonitoring provide information about exposures long past. 

The November 2009 Atlanta meeting resulted in ATSDR performing new analyses, as detailed in the 

chapters of this report. Appendix A includes short summaries of each report analyzed as a part of this 

evaluation. After careful examination of previously reported data, new data, and new science, ATSDR 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 14

has arrived at the conclusions and recommendations contained at the end of each environmental data 

chapter, the health-outcome data chapter, the biomonitoring data chapters, and in Chapter 9.

Because outside peer review is now complete, the document will become available for public comment. 

After comments are reviewed and addressed, the report will guide the future work of environmental 

and public health agencies and scientists on Vieques. 

1.7. References

[ATSDR] Agency for Toxic Substances and Disease Registry. 2003a. Public health assessment, soil 

pathway evaluation, Isla de Vieques bombing range. Atlanta: US Department of Health and Human 

Services; February.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2003b. Public Health Assessment, Air 

Pathway Evaluation, Isla De Vieques Bombing Range Vieques, Puerto Rico. Atlanta: US Department of 

Health Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry; 2003 

Aug 26.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2003c. Public Health Assessment, Fish and 

Shellfish Evaluation, Isla De Vieques Bombing Range Vieques, Puerto Rico. Atlanta: US Department of 

Health Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry; 2003 

June 27.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2001. Public health assessment, drinking 

water supplies and groundwater pathway evaluation, Isla de Vieques bombing range. Atlanta: US 

Department of Health and Human Services; October.

Barton J, Porter J. 2004. Radiological, Chemical, and Environmental Health Assessment of the Marine 

Resources of the Isla de Vieques Bombing Range, Bahia Salina del Sur, Puerto Rico. Underwater 

Ordnance Recovery, Inc.; University of Georgia. March 8, 2004.

Bauer, L.J. and M.S. Kendall (eds.). 2010. An Ecological Characterization of the Marine Resources of 

Vieques, Puerto Rico Part II: Field Studies of Habitats, Nutrients, Contaminants, Fish, and Benthic 

Communities. NOAA Technical Memorandum NOS NCCOS 110. Silver Spring, MD.

CH2MHILL. 2000. Surface Soil Investigation Report, Live Impact Area, Vieques Island, Puerto Rico. 

October 2000.

CH2MHILL. 2007. Final East Vieques Background Soil Inorganics Investigation Report, Former Vieques 

Naval Training Range, Vieques, Puerto Rico. October 2007.

Geo-Marine, Inc. 2002. Ex-USS Killen Site Investigation and Biological Characterization, Vieques Island, 

Naval Station Roosevelt Roads, Puerto Rico. June 2002.

Learned RE, Grove GR, Boissen R. 1973. A geochemical reconnaissance of the Island of Vieques, Puerto 

Rico. US Geological Survey and Puerto Rico Department of Natural Resources. Open-file report 73-155 

(order number 1866).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 15

Riegl B, Moyer RP, Walker BK, Kohler K, Gilliam D, and Dodge RE. 2008. A Tale of Germs, Storms, and 

Bombs: Geomorphology and Coral Assemblage Structure at Vieques (Puerto Rico) Compared to St. Croix 

(U.S. Virgin Islands). Journal of Coastal Research 24(4):1008–1021.

US Army. 1992. Development of methodology and techniques for identifying and quantifying products 

from open burning and open detonation thermal treatment methods-Bang Box Test Series, Volume 1, 

Test Summary. Rock Island, IL: AMMCOM 61299-6000; January.

US Army. 1992, Development of methodology and techniques for identifying and quantifying products 

from open burning and open detonation thermal treatment methods-Bang Box Test Series, Volume 2, 

Test Development. Rock Island, IL: AMMCOM 61299-6000; January.

US Army. 1992, Development of methodology and techniques for identifying and quantifying products 

from open burning and open detonation thermal treatment methods-Bang Box Test Series, Volume 3, 

Quality Control and Quality Assurance. Rock Island, IL: AMMCOM, 61299-6000; January.

[USEPA] U.S. Environmental Protection Agency/Environmental Response Team (EPA/ERT). 2001. Field 

Data Summary, Vieques Fish Assessment, Vieques, Puerto Rico. November 8, 2001.

[USGS] U.S. Geological Survey. 1997. Collecting rocks. RM Barker. June 24, 1997. Available at 

http://pubs.usgs.gov/gip/collect1/collectgip.html, accessed April 2, 2011. 

[USGS] U.S. Geological Survey. 2001. Understanding our planet through chemistry. Compiled by JE 

Taggart. Edited by CA Bales and SK Runberg. Composition by ML Johnson. Graphics by RP Walker, ST 

Smith, and SM Smith.

Young, GA. 1978. Environmental dispersion of the products of explosions of conventional ordnance at 

Vieques Island, Naval Surface Weapons Center: August 28, 1978.

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 17

2. Consumption of Fish from Reefs off the Vieques Coast

2.1. Introduction to Viequense Fish Consumption.......................................................................... 19

2.1.1. A Brief Review of Mercury............................................................................................. 19

2.1.2. Summary of ATSDR’s 2003 Fish PHA ............................................................................. 19

2.1.3. U.S.EPA and FDA Joint National Fish Advisory .............................................................. 20

2.1.4. The Vieques Marine Environment................................................................................. 21

2.2. Assessment of Available Fish Data ........................................................................................... 22

2.2.1. Fish Data from Metropolitan University........................................................................ 22

2.2.2. Fish and Seafood Data from ATSDR............................................................................... 27

2.2.3. Strength and Limitations of ATSDR’s 2001 Fish and Seafood Data ............................... 31

2.2.4. Mercury Levels in Reef Fish from Vieques .................................................................... 32

2.2.5. Toxicological Evaluation of Mercury in Vieques Fish..................................................... 37

2.2.6. Possible Mixtures Effects from Chemicals in Fish and Other Biota............................... 39

2.3. Conclusions and Recommendations......................................................................................... 40

2.3.1. Conclusions.................................................................................................................... 40

2.3.2. Recommendations......................................................................................................... 42

2.4. References................................................................................................................................ 43

2.5. Appendix 2A-1: Statistical Analysis of ATSDR Fish Data ........................................................... 47

2.5.1. Addressing the Statistical Tests and Sample Numbers ................................................. 47

2.5.2. Sample Design ............................................................................................................... 47

2.5.3. Summary of Statistics for Health-Related Hypothesis Testing...................................... 48

2.5.4. Testing Limitations......................................................................................................... 49

2.5.5. Results of the Tests (Mercury focus)............................................................................. 50

2.5.6. Testing Limitations......................................................................................................... 51

2.5.7. Mercury: Three Human Studies and U.S.EPA’s Reference Dose ................................... 53

2.6. Appendix 2A-2. Estimated Doses in Residents from Eating Vieques Fish ................................ 55

2.7. Appendix 2A-3. The Joint U.S.EPA and FDA National Fish Advisory......................................... 56
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 18

Chapter 2 Summary

At the request of scientists who visited ATSDR in 2009, ATSDR evaluated the risk from mercury in 

fish and shellfish by comparing the estimated mercury intakes with guidelines recommended by the 

National Academy of Sciences and by the U.S.EPA. 

ATSDR has identified mercury exposure from frequent consumption of marine seafood as a 

potential public health hazard. After a review of estimated mercury intakes from seafood 

consumption, ATSDR concludes that children born to women who eat fish daily from waters 

surrounding Vieques are at increased risk of adverse health effects. Possible harmful effects 

identified from studies of non-Viequense children exposed in utero involve language, attention, and 

memory, and to a lesser extent visual/spatial and motor functions. In addition, even if children were 

not exposed in utero, some children who frequently eat the same fish as their mothers eat are also 

at risk of harmful effects. This conclusion about the risk of harmful effects to the fetus and to 

children is somewhat uncertain, primarily because a person’s mercury response is itself somewhat 

uncertain. Contributing to that uncertainty is how the body handles mercury, and the sex, genetics, 

health, and nutritional status of the person who eats the fish, or how mercury is handled in the 

body. Estimating mercury intake from eating reef fish is likewise uncertain. The intake could vary 

depending on the type, frequency, and quantity of fish eaten. Contemporary information about 

Viequenses fish-eating habits and mercury levels in fish could reduce this uncertainty.

Statistical analysis showed that some fish and shellfish had higher levels of some metals and lower 

levels of other metals—iron, aluminum, copper, zinc, arsenic, barium, potassium and selenium were 

all slightly higher. These metals are materials found in bombs and in metal ships, suggesting possible 

localized contamination. But the levels were only slightly higher and the difference was only 

statistically significant when compared with a few other locations.

ATSDR recommends the following for consideration by environmental and public health agencies 

and scientists:

Following available fish advisories and maintaining fishing restrictions near the LIA;

Conducting a survey to determine the type, frequency, and quantity of fish consumed; 

Conducting additional risk assessments and statistical analyses using information gathered from 

the previously recommended fish consumption survey;

Collecting and analyzing additional fish samples from Vieques should the proposed survey and 

statistical analysis not provide sufficient public health information. Collect sufficient fish samples to 

allow analysis by species and by location; and 

Developing an educational program about mercury in fish that incorporates local habits and 

information about Viequenses’ seafood consumption.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 19

2.1. Introduction to Viequense Fish Consumption

Many Viequenses remain concerned that the U.S. Navy’s past military exercises might have 

contaminated fish and other marine life near the island. Locally harvested fish and other species are an 

important part of the Viequense diet. High contaminant levels in fish and other marine animals could 

affect the health of those who eat them. But heavy metals in fish and shellfish are not unusual. 

Depending on an area’s geology and chemical composition, fish and shellfish will assimilate a variety of 

metals in varying concentrations. Thus in populations who eat substantial quantities of fish, evaluation 

of heavy metal exposure is quite reasonable. 

During ATSDR’s November 2009 meeting in Atlanta, several scientists raised questions about mercury 

levels in fish. They reported finding residents with elevated mercury levels in hair. Were these mercury 

levels indicative of mercury body burdens generally, they might put a developing fetus at risk for 

neurological effects. The scientists questioned whether the conclusions in ATSDR’s 2003 Fish PHA 

contradicted the 2004 U.S.EPA/FDA national fish advisory for mercury. They were also concerned that 

ATSDR did not use the National Academy of Sciences’ recommendations to U.S.EPA concerning mercury 

toxicity. ATSDR therefore is reevaluating its 2003 conclusions and recommendations about mercury in 

fish from reefs surrounding Vieques. 

ATSDR’s evaluation of mercury in the Vieques environment indicates that the mercury is most likely 

coming from the global reservoir of mercury in the environment and not from past military exercises. A 

more thorough discussion of this topic occurs in Chapter 1, Section 1.3. Nevertheless, because of 

continued public health concerns, ATSDR continues its evaluation of mercury in fish.

2.1.1. A Brief Review of Mercury

Mercury is found in several chemical forms: elemental mercury, inorganic mercury, and methylmercury. 

Elemental mercury is the familiar silver material found in some thermometers. Mercury in soil is often 

inorganic mercury, while mercury in fish and shellfish is predominantly methylmercury, with small 

amounts of inorganic mercury. When elemental or inorganic mercury enters freshwater and saltwater 

environments, some of it is transformed into methylmercury, which accumulates in fish and seafood. It 

is the methylmercury form in fish that is harmful to the developing fetus and to young children. Tests for 

mercury in fish, however, often measure all forms of mercury. We refer to these tests as total mercury 

concentration or just mercury concentration. Identification of just the methylmercury or inorganic 

mercury concentrations in fish requires specific tests. 

2.1.2. Summary of ATSDR’s 2003 Fish PHA

In July 2001, ATSDR collected 104 fish and 42 shellfish samples. ATSDR analyzed the edible tissue for 

metals and explosive compounds. The 42 shellfish samples consisted of 20 conch, 7 lobster, 11 blue land 

crab, and 4 fiddler crab. Twenty-five blue land crabs comprised 11 composite samples, and 146 fiddler 

crabs comprised four composite samples. All samples were analyzed individually except the blue crab 

(combined into 11 composite samples) and the fiddler crabs (combined into four samples). As expected, 

the results showed various metals in fish and shellfish tissue. Therefore, in its 2003 Fish PHA, ATSDR 

evaluated whether fish and shellfish muscle tissues contained levels of heavy metals that would pose a
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 20

health risk. In its 2003 Fish PHA, ATSDR used fish intake rates that focused on people who ate large 

amounts (i.e., 8 ounces for adults and 4 ounces for children) and who ate fish daily. The agency also 

used standard body weights of 70 kilograms (kg) (or 154 pounds) for adults and 16 kg (35 pounds) for 

children. ATSDR further assumed that all the mercury detected in fish and shellfish was 

methylmercury—numerous fish studies support this (ATSDR 1999; Grieb 1990; Bloom 1992). In the 2003 

Fish PHA, the estimated doses were compared with ATSDR’s chronic Minimal Risk Level (MRL) for 

methylmercury. In June 2003, ATSDR released its evaluation of these data as a public health assessment 

with these conclusions:

 A variety of fish and shellfish were safe to eat every day;

 Fish and shellfish were safe to eat from any of the locations sampled, including from around the 

LIA and the sunken navy target vessel USS Killen; and

 Snapper, the most commonly consumed species, was safe to eat every day. 

These recommendations were based on the low level of mercury and other metals detected in fish 

collected from reefs, from the sunken target vessel, and from a commercial fish market on the island. 

Organic chemicals associated with past military activities were rarely detected in the seafood samples 

and then only at low levels.

2.1.3. U.S.EPA and FDA Joint National Fish Advisory

In March 2004, a year after the public health assessment, the U.S.EPA and the Food and Drug 

Administration (FDA) released a joint national fish advisory. It emphasized that fish and shellfish were an 

important part of a healthy diet. The advisory pointed out that fish and shellfish contained high-quality 

protein and other essential nutrients, were low in saturated fat, and provided omega-3 fatty acids, a 

heart healthy chemical. A well-balanced diet that included a variety of fish and shellfish could contribute 

to heart health and to children's proper growth and development. The advisory concluded that in 

particular, women and young children should include fish or shellfish in their diets (USEPA 2004; FDA 

2004).

The joint FDA/USEPA advisory acknowledged that nearly all fish and shellfish contained traces of 

mercury. For most people, the risk of mercury-related health effects from eating fish and shellfish was 

not a concern. Yet some fish and shellfish may contain levels of mercury considered unhealthy. Women 

and young children are advised not to eat them, especially in large quantities. The risks from mercury in 

fish and shellfish depend on the mercury levels in, and the amount of, fish and shellfish eaten. The FDA

and the U.S.EPA advised women who might become pregnant, women already pregnant, nursing 

mothers, and young children to avoid some types of fish and to eat fish and shellfish known to have 

lower mercury levels (USEPA 2004; FDA 2004).

The joint advisory said that by following these recommendations for selecting and eating fish or 

shellfish, women and young children would receive dietary benefits. At the same time, they would

reduce their exposure to mercury’s harmful effects. U.S.EPA and FDA made the following 

recommendations and statements:
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 21

 Do not eat shark, swordfish, king mackerel, or tilefish—they contain high levels of mercury. 

Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish lower in mercury.

In the continental United States, five of the most commonly eaten fish low in mercury are 

shrimp (0.012 ppm),

10 canned light tuna (0.12 ppm), salmon (0.01 ppm), pollock (0.04 ppm), and 

catfish (0.05 ppm). Another commonly eaten fish in the continental United States, albacore 

("white") tuna (0.36 ppm), has more mercury than does canned light tuna. U.S.EPA and FDA 

recommend limiting albacore tuna to only one 6 ounce-meal (one average meal) per week. 

 U.S.EPA and FDA recommend checking local advisories about the safety of fish caught by family 

and friends in local lakes, rivers, and coastal areas. In the absence of a local advisory, eat only up 

to 6 ounces (one average meal) per week of fish caught in local waters but do not consume any 

other fish during the week.

 U.S.EPA and FDA advise following these same recommendations when feeding fish and shellfish 

to young children, but serve smaller portions (USEPA 2004; FDA 2004). 

Note that the FDA currently compares the risk from mercury in fish with the benefits of eating fish (FDA 

2009). According to its draft risk and benefit assessment, the FDA estimated the net effect of 

consumption of different amounts of fish. The results indicated that as measured by verbal 

development, consumption of fish species low in methylmercury was likely to result in a modest net 

benefit. When FDA modeled actual consumption for the range of methylmercury concentrations (low to 

high) in fish, the likelihood was small of an adverse effect in children. In addition, FDA concluded that

fish consumption prevented a significant number of deaths from coronary heart disease and stroke each 

year in adults. FDA pointed out, however, that its risk and benefit assessment should not be construed 

as altering the agency’s then-existing fish advisory (FDA 2009). More information about FDA’s risk and 

benefit assessment is available at http://www.fda.gov/Food/FoodSafety/ProductSpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm088794.htm.

2.1.4. The Vieques Marine Environment

The following brief descriptions provide some insight into the ecological effects to the coral reefs around 

Vieques. 

 In July 2001, the U.S.EPA’s Environmental Response Team (USEPA/ERT) collected fish and 

shellfish from near-shore reefs around Vieques for ATSDR’s public health assessment. The divers 

conducting the sampling reported that unexploded ordnance (UXO) was a common sight around 

the former USS Killen (a Navy target vessel intentionally sunk to the south of the LIA) and was 

occasionally seen in a seagrass bed to the north of the LIA. Despite the presence of UXO, the 

divers observed that all sample locations supported diverse, healthy populations of marine 

organisms and that the reefs visited were in good condition. The divers also noted that with very 

few exceptions, the fish and shellfish collected appeared healthy (USEPA 2001). 

 

10 Average mercury level as reported by FDA (FDA 2004).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 22

 In November 2001, a Navy contractor (Geo-Marine) characterized the biological organisms on 

and around the former USS Killen. The purpose was to assess the health of the marine species 

and to assess potential effects on the surrounding biota. The overall conclusion was that the 

sunken vessel and its contents had no negative effects on the coral reef ecosystem; rather, they 

acted as a productive artificial reef habitat (Geo-Marine 2002).

 In June 2003, researchers from the University of Georgia and Underwater Ordnance Recovery 

collected data on the environmental integrity and ecosystem health of Vieques coral reefs. They 

reported the presence of underwater UXO and numerous 55-gallon drums in Bahia Salina del 

Sur (the bay to the southwest of the former LIA) and documented damage to the coral reefs 

(Barton and Porter 2004). 

 In May and October 2007, the National Oceanic and Atmospheric Administration (NOAA) 

conducted an ecological characterization of the marine resources of Vieques. They found little 

evidence of any differences in marine resources, nutrients, or contaminants among the different 

former land-use zones. Biota, nutrients, and contaminant levels around Vieques generally match 

those of other coral reef ecosystems (Puerto Rico and U.S. Virgin Islands) and appear shaped by 

regional-scale processes rather than local factors. The results of their study did not support the 

hypothesis that military activities negatively affected the marine environment around Vieques. 

Nor did their study support the opposite hypothesis: that the lack of development on two-thirds 

of the island positively influenced the marine environment (Bauer and Kendall 2010).

 In July 2008, the National Coral Reef Institute published the results of a study that investigated 

whether the coral reefs around Vieques were in better or worse shape than the reefs around St. 

Croix. Even though the researchers observed evidence of past military activity at Vieques (e.g., 

unexploded bombs, casing, and ammunition shells to the north and south of the LIA), they 

found no differences in living benthic cover and coral assemblage structure between the two 

islands. They concluded that the effects of Caribbean-wide natural disturbances (disease and 

storms) had a greater impact on the coral reefs than did the former military activities on Vieques 

(Riegl et al. 2008).

2.2. Assessment of Available Fish Data

Two sets of data are available on metal levels in fish. One is from the Metropolitan University in Puerto 

Rico, and the other is from ATSDR. Both sets of data originate from sampling events conducted from 

1999–2000 or in 2001. 

2.2.1. Fish Data from Metropolitan University

From December 1999 to April 2000, Dr. Doris Caro with the Metropolitan University (i.e., Universidad 

Metropolitana), School of Environmental Matters, collected 52 fish from two markets in Vieques

(northern Vieques and Esperanza) and compared the results with 26 fish collected from fish markets 

from the Parguera area on Puerto Rico’s mainland (Caro 2000). She also conducted a survey of 51 

Vieques residents and fishers to determine the most frequently consumed fish. Among the 51 residents 

surveyed, Dr. Caro reported the following fish consumption frequencies:
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 23

 20% never eat fish,

 47% eat fish 1–2 times a week, 

 18% eat fish 3–4 times a week, and

 16% eat fish five or more times a week11 (Caro 2000).

Dr. Caro thus reported that 34% of Viequenses ate fish 3–4 or more times a week. The more extensive, 

random PRDOH survey in 2004 supported her findings. The PRDOH manuscript reported that 38% of 

Viequenses ate fish three or more times a week. Both of these surveys show that a significant portion of 

Viequenses eat fish regularly. ATSDR’s assumption that a significant proportion of Viequenses eat fish 

daily therefore seems reasonable, although the precise percentage is not known. 

Dr. Caro also provided information about the type of fish the 51 respondents ate. Table 2-1 shows these 

results from Dr. Caro’s survey along with the number of responders who ate certain fish (Caro 2000).

Dr. Caro concluded that the detected metal concentrations in Vieques fish did not show that metals in 

fish bioaccumulate, pointing to the absence of any clear relationship between fish weight, size, and 

metal content (Caro 2000). ATSDR’s data, however, did show bioaccumulation in some species.

Mercury concentrations in fish collected by Dr. Caro are shown in Table 2-2 as ppm, although whether 

the reported concentrations are dry weight or wet weight is uncertain. We have attempted to contact 

the laboratory to ascertain how the data were reported, but we have not received a response. The 

described method produces raw results in dry weight. The mercury concentrations were extremely low 

(lower than ATSDR’s results on wet or dry weight basis), but this latter fact could be explained by the 

very low weights of the fish. Uncertainty thus remains about whether the results are wet weight or dry 

weight. Regardless, Dr. Caro concluded that the results show that mercury concentrations are higher in 

fish from markets in Vieques compared with the control population from Parguera (Caro 2000).

These conclusions were reached using averages calculated in a manner inconsistent with U.S.EPA

methods. Dr. Caro states that the results clearly justify a need for further sampling. We agree with this 

last statement.

 

11 Percentages are rounded to whole numbers.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 24

Table 2-1. The type of fish that the 51 respondents ate as reported by Dr. Doris Caro in her survey of 

Viequenses.

Number of 

respondents

Spanish Common 

Name

Scientific Name English Common Name

41 Colirrubia Ocyurus chrysurus Yellowtail snapper

32 Mero cabrilla Epinephelus guttatus Rock hind 

29 Langosta Palinurus sp. Spiny lobster

26 Peje puerco Balistes vetula Queen triggerfish

24 Sierra Scomberomorus maculatus Spanish mackerel

23 Capitán Unknown Hogfish

21 Cotorro Sparisoma sp. Parrotfish

20 Chapin Gallina Lactophrys trigonus Trunkfish

13 Bonito Euthynnus alletteratus Little tunny

11 Negra Lutjanus bucanella Blackfin snapper

11 Dorado Coryphaena hippurus Dolphinfish (Mahi-mahi)

11 Chillo Lutjanus vivanus Silk snapper

11 Boquicolora’o Haemulon plumier Striped (white) grunt

10 Dentex (Corvina) Odontoscion dentex Reef croaker

8 Atun Thunnus Tuna

8 Tibarón Numerous genera (e.g., 

Etmopterus, Carcharhinus)

Shark

5 Sharpsnout* unknown Sharpsnout

4 Abanico† Makaira nigricans Blue marlin

4 Salmón Salmo and Oncorhynchus Salmon

3 Carrucho Strombus Conch

1 Robalo Centropomus Snook

1 Salmonete Mulloidichthys or 

Pseudupeneus

Goatfish

1 Arrayao Lutjanus synagris Lane snapper

1 Jurel aleta 

amarilla

Caranx hippos Crevalle Jack

*Because a genus name is not provided, whether “sharpsnout” refers to the sharpsnout stingray, sharpsnout 

seabream, or sharpsnout flounder is unclear.

†ATSDR is unsure of the Viequense Spanish common name for the blue marlin. Other possible names include 

aguja, castero, prieta, and voladora.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 25

Dr. Caro further states that her report should be viewed as a starting point for a more comprehensive 

survey. She recommended the following:

1. Choose sentinel species, including some close to sediments.

2. Obtain fish samples in other areas of the island, mainly in ordnance-free areas.

3. Sample fish after the beginning of military exercises and analyze it accordingly.

12

4. Sample and analyze crustaceans (e.g., crabs, lobster) and other aquatic life, such as snails.

5. Assign additional funds for the enhancement of the proposed study.

6. Perform a risk-assessment study of the species analyzed and the results obtained.

Table 2-2. Average fish-mercury levels from fish markets in northern Vieques, southern Vieques 

(Esperanza), and Parguera, Puerto Rico (Caro 2000).

Fish Northern Vieques 

(n)

ppm*

Southern Vieques 

(Esperanza) (n)

ppm

Parguera (n)

ppm

Arrayao (lane snapper) 0.048 (3) 0.018 (2)†0.000 (1)

Boquicolora’o (striped grunt) 0.029 (6) 0.024 (6)‡0.008 (4)

Colirrubia (yellow tail snapper) 0.019 (7) 0.022 (3) 0.004 (2)

Cotorro Azul (blue parrotfish) 0.002 (3) NA 0.001 (2)

Cotorro Rojo (stoplight parrotfish) 0.000 NA 0.001 (3)

Cotorro Verde (redband parrotfish) 0.010 (1) NA 0.007 (5)

Salmonete de Altura (goatfish) 0.038 (1) NA 0.001 (2)

Pluma (dogfish) NA 0.018 (3) 0.008 (2)

Mero Cabrilla (Red hind) 0.010 (4) 0.015 (1) 0.011 (3)

n = number of samples

NA = No sample available. 

*Whether the concentrations represent wet weight or dry weight is unknown; no indication has been provided by 

the laboratory or Dr. Caro’s report. The table here uses the values calculated by Caro et al. 2000 from Appendix 10. 

Her averages include values below the detection level of the instrument.

† An apparent typographical error appears in the original table in the main text of Dr. Caro’s report. Using data 

from Appendix 10 in the report shows that the average is 0.018 ppm, not 0.048 ppm.

‡ An apparent typographical error appears in the original table in the main text of Dr. Caro’s report. Using data 

from Appendix 10 in the report shows that the average is 0.024 ppm, not 0.029 ppm.

 

12 Note that sampling fish after the beginning of military exercises is no longer possible—all such exercises have 

ceased.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 26

The Metropolitan University data have several strengths, but some limitations as well. To ensure that 

metal concentrations in fish were those that people were consuming, investigators collected their fish 

samples from two local markets. Investigators interviewed 51 residents and fishers about their fisheating habits and where those fish were bought or caught. Investigators learned their Vieques fish 

market samples included fish from the reefs and the open ocean. Metal concentrations in Vieques 

market fish did not therefore necessarily represent metal concentrations in reef fish near Vieques. Also, 

the participants were not randomly selected, and a limited number of surveys were conducted. All this 

adds some uncertainty to identifying all the fish species that Viequenses eat and to the frequency of 

Viequense fish consumption. And as stated, with regard to the fish sampling results, the authors did not 

specify whether their results were wet or dry weight. This prevents a reliable estimation of human doses 

from eating fish. Despite these limitations, however, one peer reviewer of this report requested 

additional analysis of Caro’s data. 

Therefore, with qualification, after Dr. Caro’s data are regrouped and reaveraged, Dr. Caro’s data can be 

compared with ATSDR’s data. Because Dr. Caro reported averages for fish according to species rather 

than fish family, some locations have just one or two fish to compare. Also, in calculating averages, Dr. 

Caro used values below the detection level. 

ATSDR used the raw data reported in Appendix 10 of Dr. Caro’s report to group fish species into families 

from both Vieques markets. In this way, the results provide statistically significant numbers comparable

with ATSDR’s data:

 Arrayo was combined with colirrubia to represent the snapper family at both Vieques markets,

 Cotorro rojo was combined with cotorro azul and cotorro verde to represent the parrotfish

family at both Vieques markets, 

 Mero mantequilla were combined with mero cabrilla to represent the hind family at both 

Vieques markets, and 

 Boquicolora were combined with pluma to represent the grunt family at both Vieques markets. 

To calculate averages, all laboratory results below the analytical detection levels were then set at onehalf the detection levels. Table 2-3 shows average mercury levels in various fish families using Dr. Caro’s 

(regrouped) 2000 data and using ATSDR’s 2001 data. Dr. Caro’s data show average mercury levels by fish 

family that are below the average levels reported by ATSDR for both wet weight and dry weight. Note 

that if Dr. Caro’s data are dry weight, the wet weight concentration will be lower.

Although for Dr. Caro’s data the mercury concentration basis (wet vs. dry weight) is unknown, the fish 

families’ relative rankings provide insight for exposure assessments. The fish families shown in Table 2-3 

are in order of increasing average mercury concentration (according to ATSDR’s order). Three of five 

families in Dr. Caro study have similar relative ranking to ATSDR’s ranking. Goatfish might have a higher 

relative ranking in Dr. Caro study because of the small number (4) of Goatfish samples. The snapper Dr. 

Caro collected might have a higher relative ranking, but grunt and hind fish she collected were much 

smaller than ATSDR’s. Some conclusions from these combined data follow:
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 27

1. Parrotfish have low mercury levels. 

2. All of Dr. Caro’s fish families have average mercury levels below U.S.EPA’s screening level of 

0.049 ppm (wet weight)13. This conclusion is true whether Dr. Caro’s average is wet weight or 

dry weight.

3. ATSDR identified three families (goatfish, hind, and grunt) above the U.S.EPA screening level of 

0.049 ppm (wet weight).

Because Dr. Caro’s grunt and hind were much (~30%) smaller than ATSDR’s grunt or hind and because 

we know that mercury accumulates in larger fish, it is likely that all (these) Vieques fish have very low 

levels—that is, until they grow larger. In addition, grunt and hind are two families that accumulate more 

mercury when they are larger. 

Table 2-3. Average fish-mercury levels: Vieques

Fish Caro et al. (ppm)*ATSDR (ppm-wet) ATSDR (ppm-dry)

Parrot 0.004 0.009 0.046

Snapper 0.026 0.048 0.218

Goatfish 0.038 0.080 0.344

Hind 0.016 0.116 0.551

Grunt 0.024 0.185 0.887

All fish (fin fish) 0.020 0.091 0.427

*Whether Dr. Caro’s results are wet or dry weight is unknown

2.2.2. Fish and Seafood Data from ATSDR

ATSDR’s 2001 sampling and analysis activities focused on whether muscle tissues from commonly 

consumed fish and shellfish contained levels of heavy metals and explosives compounds that would 

result in health effects. To assist in these activities, ATSDR sought advice and worked with the U.S.EPA’s 

Environmental Response Team (EPA/ERT) to collect and analyze fish and shellfish from the coastal 

waters around Vieques and from land and beaches near the shore.

ATSDR collected fish and shellfish from five reefs surrounding Vieques and one local fish market. Two 

reefs were off the eastern portion of the island near the Live Impact Area, where military exercises 

formerly occurred and one of these locations included the area where the USS Killen is located. The 

three other reefs were off the central and western portions of the island. Land crabs were collected 

from two locations within the Live Impact Area and one location on the western portion of the island. 

Efforts were made to collect from each reef location and from the fish market five fish within a family 

 

13 Using the Reference Dose (RfD) for methylmercury, U.S.EPA established a fish screening level of 0.049 ppm 

mercury for recreational and subsistence fishers. More information about U.S.EPA’s screening levels is located at 

this Web address: http://www.epa.gov/waterscience/fish/advice/volume2/v2cover.pdf.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 28

(e.g., grunt and hind from the genus Epinephelus in the Serranidae family or snappers from the genera 

Lutjanus and Ocyurus within the family Lutjanidae). At most locations, ATSDR was able to collect five fish 

from each family (e.g., Epinephelus, Sparisoma and Haemulon families). But at several locations, five fish 

could not be collected for some families (see Table 2-4).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 29

Table 2-4. Fish and shellfish collected by ATSDR

Common 

Name and 

Taxonomic 

Family

Genus and species Species # 

and Family 

Total

Loc. #1

Reef

North 

LIA

Loc. #2

Reef

South

LIA

Loc. #3

Reef

South

Esperanza

Loc. #4

Reef NW

Isabel

Segunda

Loc. #5

Fish

Market

Loc. #6

West

End

Red hind Epinephelus 

guttatus

19 5 1 0 5 5 3

Rock hind Epinephelus 

adscensionis

8 0 4 4 0 0 0

Graysby Epinephelus 

cruentatus

1 0 0 1 0 0 0

Coney Epinephelus fulvus 2 0 0 0 0 0 2

Total # Serranidae family Total = 

30

Total = 5 Total = 5 Total = 5 Total = 5 Total = 5 Total = 

5

Schoolmaster 

snapper

Lutjanus apodus 5 0 3 2 0 0 0

Grey snapper Lutjanus griseus 3 0 2 1 0 0 0

Yellowtail 

snapper

Ocyurus chrysurus 11 0 0 1 2 5 3

Total # Lutjanidae family Total = 

19

Total = 0 Total = 5 Total = 4 Total = 2 Total = 5 Total = 

3

Stoplight 

parrotfish

Sparisoma viride 19 4 1 5 4 0 5

Redband 

parrotfish

Sparisoma 

aurofrenatum

5 1 3 0 1 0 0

Redfin 

parrotfish

Sparisoma 

rubripinne

1 0 1 0 0 0 0

Total # Scaridae family Total = 

25

Total = 5 Total = 5 Total = 5 Total = 5 Total = 0 Total = 

5

White Grunt Haemulon plumieri 7 0 2 0 0 5 0

Spanish 

Grunt

Haemulon 

macrostomum

1 0 0 1 0 0 0

Bluestriped 

Grunt

Haemulon sciurus 12 5 3 4 0 0 0

French Grunt Haemulon 

flavolineatum

4 0 0 0 0 0 4

Total # Haemulidae family Total = 

24

Total = 5 Total = 5 Total = 5 Total = 0 Total = 5 Total = 

4
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 30

Fish and shellfish tissues were analyzed for explosives compounds. No explosive residues were detected

in fish tissues from any sample location. Of the four shellfish species, only fiddler crabs were shown to 

contain the explosives compound HMX. RDX was detected in fiddler crabs, but the level was so low that 

an accurate concentration could not be measured. We should note that the laboratory analysis 

identified trace levels of a chemical with the same characteristics (i.e., retention time) of RDX 

(hexahydro-1,3,5,-triazine) in two samples: the fiddler crabs and the trunkfish. These trace levels were 

well below the RDX detection level and estimated doses were well below the RDX health guideline.

Furthermore, the natural toxins within the trunkfish have the same retention time on the gas 

chromatogram as RDX. Therefore, we cannot conclusively determine whether RDX was present in the 

trunkfish tissues. The 2003 Fish PHA concluded that because residents did not eat fiddler crabs, the 

fiddler crab HMX would not cause harmful effects in people. No explosives compounds were detected in 

conch, lobster, or land crab samples from any location. Fiddler crabs and land crabs were collected from 

locations 1 and 2 on the eastern end of the island, and land crabs were collected from location 6 on the 

western end of the island (see Figure 2-1).

Yellow 

Goatfish

Mulloidichthys 

martinicus

4 0 0 3 0 0 1

Spotted 

Goatfish

Pseudupeneus 

maculatus

1 1 0 0 0 0 0

Total # Mullidae family Total = 5 Total = 1 Total = 0 Total = 3 Total = 0 Total = 0 Total = 

1

Honeycomb 

Cowfish

Lactophrys 

polygonia

1 0 0 0 0 1 0

Queen Conch Strombus gigas 20 5 5 5 0 0 5

Spiny Lobster Panulirus argus 7 1 0 1 0 5 0

Blue Land Crab Cardisoma 

guanhumi

11 5 5 0 0 0 1

Fiddler Crab Uca sp. 4 2 2 0 0 0 0

Note: Blue land crabs and fiddler crabs are listed by the number of composite tissue samples analyzed, not by the 

number of individuals captured. The meat from several land crabs was composited until a sufficient quantity of 

meat was obtained. To ensure a sufficient sample was collected for analysis, the whole fiddler crabs were 

composited and were analyzed.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 31

Figure 2-1. ATSDR fish and shellfish sample locations.

In addition to explosive compounds, ATSDR analyzed the same fish and shellfish tissues for heavy 

metals. ATSDR collected 104 fish and 42 shellfish samples and analyzed the edible tissue for metals and 

explosive compounds. The fish samples represent 17 different species and can be grouped into these 

fish families: 30 hinds (or groupers), 19 snappers, 25 parrotfish, 24 grunts, 5 goatfish, and 1 cowfish. The 

42 shellfish samples consisted of 20 conch, 7 lobster, 11 composite, blue land crab, and 4 composite 

fiddler crab samples. Twenty-five blue land crabs comprised 11 composite samples and 146 fiddler crabs 

comprised four composite samples. All samples were analyzed individually except the blue crab 

(combined into 11 composite samples) and the fiddler crabs (combined into four samples). Here we 

refer to the individual and composite samples collectively as 42 shellfish samples. 

2.2.3. Strength and Limitations of ATSDR’s 2001 Fish and Seafood Data

ATSDR’s 2001 sampling effort included several strengths:

 ATSDR used multiple information sources to identify the preferred types of fish and shellfish for 

collection. One important source was a Puerto Rican university report containing survey 

information about the frequency and types of fish eaten (Caro 2000). ATSDR substantiated the 

survey results with information from the petitioner and other residents, the Vieques Special 

Commission Report, and visits to the local fish markets on Vieques.

 ATSDR identified snapper (Lutjanus and Ocyurus species) as the most frequently eaten fish 

followed by hind (Epinephelus species) and grunt (Haemulon species).

 Fish and shellfish were collected from five marine locations and from one commercial fish 

market on the island. Land crabs were collected from three surface locations (see Figure 2-1).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 32

 In designing the sample plan and in collecting the samples, ATSDR partnered with the U.S.EPA’s 

Environmental Response Team, which has extensive experience in sampling and analyzing fish. 

The U.S.EPA recommended that ATSDR collect five fish per family group.

 ATSDR collected 104 fish and 42 shellfish samples. Although most samples represented one 

organism, crab samples represented a composite of three or more organisms.

 ATSDR used standard-default fish consumption intakes. These included intake rates that focused 

on high-end fish consumers as well as standard body weights for adults and children. ATSDR also 

used the agency’s chronic, oral MRL for mercury. This MRL underwent rigorous scientific and 

peer review when it was developed.

 ATSDR followed many of the criteria described in the U.S.EPA’s Guidance for Assessing Chemical 

Contaminant Data for Use in Fish Advisories, Volume 1, Fish Sampling and Analysis, Third Edition 

(USEPA 2000). These guidelines describe among other techniques how to identify those fish that 

should be sampled, how to identify the fish tissue that should be analyzed, and how to 

composite fish tissue. 

But ATSDR’s 2001 sampling effort also had limitations. Most notably, the 2001 sample design was not 

consistent with some important criteria found in current sample designs for fish advisories. The U.S.EPA

and the State of California recommend these newer criteria when developing fish consumption 

advisories. Regarding the appropriate number of fish to sample, the State of California believes the 

sample design should include either 1) a minimum of three composite samples with each composite 

consisting of three fish, or, preferably, 2) nine individual fish samples for each species of concern from 

each water body. When a species has a large size range, fish samples, when feasible, should be collected 

from multiple legal or edible sizes. Following this sampling protocol allows estimation of the range and 

variation of contaminant concentrations at a particular site and derivation of a representative mean 

concentration for use in developing fish consumption advisories (State of California 2009). The U.S.EPA

currently recommends a statistical analysis to determine the most appropriate number of fish in a 

composite sample and the most appropriate number of composite samples. At a minimum, U.S.EPA says 

the sample design should consist of three composite samples, with three fish per composite. If the 

contaminant concentration in a fish species is highly variable, more composite samples and more fish in 

each composite are needed to estimate the average concentration of the contaminant in that species. 

These recommendations were developed to determine whether average mercury levels in a fish species 

would exceed U.S.EPA’s 0.049 ppm (wet weight) screening level for mercury in fish. When estimating 

human exposure to mercury, other sample designs might also provide reliable data.

2.2.4. Mercury Levels in Reef Fish from Vieques

Using ATSDR’s 2001 fish sample results, the agency chose to analyze contaminant levels in individual 

fish—acceptable when a sufficient number of fish of each species or each family from each location are 

caught and analyzed. The maximum number of individual fish caught and analyzed for each species at 

each location was five. Table 2-4 summarizes the number of fish species and number of fish in each 

family analyzed at each location.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 33

Although the U.S.EPA recommends against combining species when determining contaminant levels, the 

State of California says similar species can be combined (e.g., bass) because species within a family 

group are likely to have similar lifestyles. And because more than nine fish were collected within each 

family, sufficient samples were available to evaluate hind (Epinephelus species), snapper (Lutjanu and 

Ocyurus species), parrotfish (Sparisoma species), and grunt (Haemulon species)—if the data from all 

locations were combined. But grouping the data in this way introduced some uncertainty or bias. For 

example, certain species within a family had higher or lower contaminant levels than the average for 

that family. So having too many French grunt will create a high bias for all grunt. This was important for 

the fish ATSDR collected in Vieques—the mercury concentrations were highly dependent on species 

(and family). Grouping the data also limited evaluation of fish data by location. Table 2-4, above,

identifies those locations with more samples of one species or another. This table helps identify where 

comparisons can be made by species and where comparisons are only possible by combining species 

within a family. For example, in Table 2-4, five red hind (first line of data) were collected from locations 

1, 4, and 5—this suggests that red hind can be compared between locations 1, 4, and 5. Therefore, 

should we want to compare other locations, we would have to rely on other species of hind, which 

introduces added uncertainty due to the differences among the hind species. 

ATSDR compensated for this uncertainty in part by a statistical analysis of the 2001 fish data. Table 2-5

provides the average concentrations for each species and family collected at the six locations.

Table 2-5 permits comparison of mercury levels in seafood by family, by location, and, in some cases, by 

individual species at a location. ATSDR’s evaluation of the fish data resulted in new conclusions. A 

principal new conclusion was that the fish data represented enough fish to make numerous, statistically 

significant determinations. Statistical tests provided in Chapter 2, Section 2.5, Appendix 2A-1 indicate 

that mercury concentrations were highly dependent on family, on species within some families, and by 

size of fish within some species. But the fish-mercury levels near the LIA were not significantly higher 

than in the other locations. 

Other new conclusions in this report include

• Mercury was lower in shellfish and higher in finfish.

• Mercury in fish was highly dependent on the family and on fish species. Mercury was higher in 

two fish families (i.e., grunt and hind, 0.18 ppm and 0.12 ppm, respectively) compared with 

other families sampled (e.g., parrotfish and snapper, 0.01 ppm, and 0.05 ppm, respectively). 

• Mercury in hind was associated with fish weight; larger hind typically had more mercury.

• The average mercury concentration in grunt and hind was higher than U.S.EPA’s 0.049-ppm 

screening level. Mercury levels in parrotfish were statistically lower than U.S.EPA’s screening 

level of 0.049 ppm and lower than the overall average of 0.1 ppm. 

• Snapper averaged less than, but not statistically different from, the U.S.EPA 0.049 ppm 

screening level, and statistically less than 0.1 ppm.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 34

Table 2-5. Average total mercury in ATSDR-collected fish and shellfish

Common Name 

and Taxonomic 

Family

Genus and species Arithmetic Mean Mercury Levels (ppm wet weight)

All 

Locations

Loc #1 

Reef 

North 

LIA

Loc #2 

Reef 

South 

LIA

Loc #3 

Reef South 

Esperanza

Loc #4 

Reef 

Isabel

Segunda

Loc #5 

Reef 

Market

Loc #6 

Reef 

West

End

Red Hind Epinephelus guttatus 0.091 0.078 (0.038) NS 0.10 0.12 0.057

Rock Hind Epinephelus 

adscensionis 0.15 NS 0.13 0.17 NS NS NS

Graysby Epinephelus cruentatus (0.12) NS NS (0.12) NS NS NS

Coney Epinephelus fulvus 0.21 NS NS NS NS NS 0.21

Total average Serranidae family 0.12 0.078 0.12 0.16 0.10 0.12 0.12

Schoolmaster 

snapper

Lutjanus apodus 0.045 NS 0.058 0.053 NS NS NS

Grey snapper Lutjanus griseus 0.061 NS 0.032 (0.067) NS NS NS

Yellowtail 

snapper

Ocyurus chrysurus 0.046 NS NS (0.048) 0.073 0.037 0.040

Total # Lutjanidae family 0.048 NS 0.055 0.045 0.073 0.037 0.040

White grunt Haemulon plumieri 0.098 NS 0.068 NS NS 0.11 NS

Spanish grunt Haemulon 

macrostomum

(0.21) NS NS (0.21) NS NS NS

Bluestriped 

grunt

Haemulon sciurus 0.22 0.21 0.24 0.22 NS NS NS

French grunt Haemulon flavolineatum 0.22 NS NS NS NS NS 0.22

Total # Haemulidae family 0.18 0.21 0.17 0.22 NS 0.11 0.22

Stoplight 

parrotfish

Sparisoma viride ND* ND* (ND)* ND* ND* NS ND

Redband 

parrotfish

Sparisoma 

aurofrenatum

0.015** (ND)* 0.020 NS (ND)* NS NS

Redfin 

parrotfish

Sparisoma rubripinne (0.016) NS (0.016) NS NS NS NS

Total # Scaridae family 0.023M ND* 0.016 ND* ND* NS ND

Yellow goatfish Mulloidichthys 

martinicus

0.088 NS NS 0.098 NS NS (0.059)

Spotted 

goatfish

Pseudupeneus 

maculatus

(0.045) (0.045) NS NS NS NS NS

Total # Mullidae family (0.080) (0.045) NS 0.098 NS NS (0.059)
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 35

NS = The species was not sampled at the given location

ND = Not Detected (range of detection levels in marine live varied 0.0039-0.0085)

(#) = Parenthesis around a value connote a single measurement rather than an average

*= All sample results for this species at this location were ND

**=The value was calculated with at least two samples that were ND

M =The preceding value represents the maximum collected at the given locations as most samples were ND

ATSDR’s evaluation would improve by having more information about the consumption frequency of

 Reef fish, ocean-going fish, and canned fish by sex and by age group,

 Various fish species by sex and by age group, and

 Portion size by sex and by age group.

The 2001 U.S.EPA analytical report on the fish and shellfish samples provided chemical results and 

statistical metal analysis (USEPA 2001). U.S.EPA’s statistical analysis of the fish and shellfish data 

identified that some fish and shellfish species had slightly higher levels of iron, aluminum, copper, zinc, 

arsenic, barium, selenium, potassium, and iron in the samples collected near the submerged bombs off

the LIA coast. But the levels were only slightly higher and the difference was only statistically significant 

when compared with a few reef locations.

U.S.EPA’s report did not study further the specific sources for these slight increases (USEPA 2001). The 

U.S.EPA report did provide results for many common explosive organic chemicals, but explosive 

chemicals rapidly decay into other chemicals that may not be as easily detected. 

Nevertheless, the chemical results indicated the presence of HMX and the possible presence of RDX in 

fiddler crabs. Both of these chemicals are known to break down rapidly in the marine environment. For 

most fish, uptake of these chemicals is low; it is lowest in fish with higher oil content, and most species 

rapidly excrete the chemicals (Ownby et al. 2005; Yoo et. al 2002; Helene et al. 2003; Lotufo et al. 2005;

Lotufo and Lydy 2005; Houston and Lutufo 2005; Blackburn et al. 2004). When reviewing information for 

a chemical that had not been ruled out, we identified picric acid as a possible bomb component at some 

bombing ranges; however, we could not verify that it was used in Vieques. Some samples were collected 

Common Name 

and Taxonomic 

Family

Genus and species Arithmetic Mean Mercury Levels (ppm wet weight)

All 

Locations

Loc. #1 

Reef 

North 

LIA

Loc #2 

Reef 

South 

LIA

Loc #3 

Reef South 

Esperanza

Loc #4 

Reef 

Isabel 

Segunda

Loc #5 

Reef 

Market 

Loc #6 

Reef 

West 

End

Honeycomb 

Cowfish

Lactophrys polygonia (0.0082) NS NS NS NS (0.0082

)

NS

Queen Conch Strombus gigas 0.016** 0.018M 0.020M 0.033 NS NS ND*

Spiny Lobster Panulirus argus 0.031 (0.031) NS (0.047) NS 0.028 NS

Blue Land Crab Cardisoma guanhumi 0.028M 0.028M 0.021M NS NS NS (ND)*

Fiddler Crab Uca sp. ND* ND* ND* NS NS NS NS
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 36

from groundwater and soil but picric acid was either not detected or the sample was rejected because 

of analytical problems. Picric acid is one explosive compound that does not decay rapidly in the marine 

environment. While picric acid is not typically used in bombs, it is an explosive compound used by the 

military. It does not quickly degrade in the sediment, but fish metabolize and excrete it rapidly (Yost et 

al. 2007; Nipper et al. 2001; Burton et al. 1983 and 1984; Cooper et al. 1984).

Slightly higher military exercise-related chemicals were found in some seafood in the southern LIA area 

compared with other areas, such as,

 HMX and trace levels of RDX explosives compounds were found in the LIA fiddler crabs;

 Aluminum and potassium were slightly higher in some LIA fish (grunts, parrotfish) compared 

with other reef locations:

o Aluminum in south LIA grunt compared with west end and market,

o Aluminum in north LIA parrotfish compared with west end,

o Aluminum in south LIA parrotfish compared with all locations except Esperanza,

o Potassium in south LIA gruntfish compared with west end,

o Potassium in south LIA parrotfish compared with Isabel 2,

 Copper was slightly higher in some LIA species (grunts, conch) compared with other reef 

locations:

o Copper in south LIA conch compared with North LIA, Esperanza, and west end,

o Copper in north LIA conch compared with Esperanza and west end,

o Copper in south LIA grunt compared with North LIA and Esperanza

 Iron was slightly higher in some LIA species (land crabs, snappers) compared with other reef 

locations:

o Iron in snapper at south LIA compared with West End,

o Iron in snapper at south LIA compared with North LIA,

o Iron in crabs at south LIA compared with North LIA (USEPA 2001).

Mercury levels in LIA fish were not significantly different from mercury levels in fish from other Vieques 

reefs. Mercury has been mentioned as a contaminant of concern because mercury was historically used 

in detonators (Garcia et. al. 2000). The data originally provided by the Navy on the composition of the 

bomb casings indicated the casings did not contain mercury. This is consistent with information on the 

Material Safety Data Sheets available for steel. The Air PHA indicated that the estimated total annual 

emissions of mercury to the air were very low (i.e., 0.14 pounds per year). The source of mercury air 

emissions was trace amounts in the explosive charge of some bombs and naturally occurring mercury in 

the soil ejected into the air following detonation. Therefore, past military exercises do not appear to be 

a significant source of mercury in the Vieques environment.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page 37 

Average mercury levels in LIA soils was 0.02 ppm, with the highest level detected at 0.086 ppm. NOAA 

determined that one of 29 soil samples had a mercury level that could be considered above naturally 

occurring levels (NOAA 2010). But two observations suggest that the LIA is not currently the primary 

source of mercury in fish tissues. First, most mercury levels in LIA soils appear to be at naturally 

occurring levels with no significant spatial variation to suggest mercury levels are higher in the LIA. 

Second, ATSDR’s fish sampling study did not appear to find unusually elevated tissue concentrations of 

mercury in Vieques reef fish. A more plausible explanation for the mercury levels found in fish is that 

they resulted from the global reservoir of mercury circulating through the environment. 

2.2.5. Toxicological Evaluation of Mercury in Vieques Fish 

The wet-weight/dry-weight nature of the Metropolitan University fish data is unknown. Those data, 

then, provide only speculative insight into contaminant levels. That is, the data can be only compared 

with fish from Parguera, the study’s control population. For quantitative dose estimates, the data are 

unusable;14 doses calculated using these data would be unreliable. A toxicological evaluation will 

therefore incorporate ATSDR’s fish data, which have been converted from dry weight in ppm to wet 

weight in ppm. Compared with Dr. Caro’s data (see Table 2-3), ATSDR’s data will provide a higher 

mercury exposure estimate as the fish were larger and the mercury concentrations are higher. Also 

compared with Dr. Caro’s data, the higher mercury concentrations in ATSDR’s data could possibly result 

from ATSDR having collected larger fish, which tend to accumulate higher mercury levels. 

Several scientists attending ATSDR’s November 2009 meeting on Vieques raised concerns about ATSDR 

not using U.S.EPA’s Reference Dose (RfD) for methylmercury and not considering the National Academy 

of Sciences’ (NAS) recommendations concerning methylmercury. The scientists noted that Puerto Ricans 

typically have lower body weights and that Viequenses have high fish consumption rates. They 

suggested, therefore, that ATSDR evaluate the risk for residents with lower body weights and with 

higher fish intake. ATSDR used the following parameters to recalculate the doses for women of 

childbearing age and for children: 

1. A range of body weights from 4.5 to 100 kg (9.9 to 220 pounds): 

a. Children (1–2 years; 3–5 years; 6–8 years; 9–14 years; 15–18 years); and 

b. Adult women (18–54 years) (USEPA 1997). 

2. A range of age-specific meal portion sizes, including the 50th, 95th, and 99th percentile. 

a. Adult women’s portion sizes were 3 oz, 8 oz, and 13.9 oz. 

 

14 Laboratory results for chemicals in fish are initially measured as dry weight because the moisture is removed 

from fish tissue before analyzing for the chemical. Once the moisture is removed, a fish sample might contain 1 

ppm of a chemical as dry weight. To estimate exposure, the dry-weight concentration is usually converted to a 

wet-weight concentration; fish consumption is usually measured as ounces of fresh (wet) fish consumed. Thus to 

know whether the results are reported as wet weight or dry weight is important. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 38

b. Children’s portion size varied by age (see Table 2-6). For example, 3–5 year old girls have 

portion sizes of 2.5 oz, 6 oz, and 8.5 oz at the 50th, 95th, and 99th percentile, respectively 

(USEPA 1997).

3. Average mercury levels were recalculated using 1⁄2 the detection limit for the approximately 25% 

of fish that had nondetectable mercury levels (ATSDR 2005). Most of the nondetectable mercury 

levels were found in parrotfish. Average mercury level for all fish was 0.1066 ppm using the 95th 

upper confidence limit (UCL) of the mean with a maximum mercury level in a bluestriped grunt 

of 0.33 ppm.

4. Some scientists were concerned that the 2003 Fish PHA used national average weights to 

represent exposure dose. This report provides exposure estimates using a wide range of weights 

for various ages. Estimated doses also were calculated on a continuous weight profile from 9.9 

to 220 pounds and increasing meal size up to the 99th percentile (See Table 2A-1 in Chapter 2, 

Section 2.6, Appendix 2A-2.)

5. The estimated doses were compared with U.S.EPA’s RfD for methylmercury of 0.1 μg/kg/day. 

Chapter 2, Section 2.2.5 provides more information about methylmercury’s toxic effects.

ATSDR also considered the National Academy of Sciences’ recommendations to the U.S.EPA. The NAS 

recommended that U.S.EPA use the Faroe Islands study to develop the agency’s Reference Dose. They 

also suggested the study and the effect levels that should be considered. 

Table 2-6. 50th, 95th, and 99th fish portion size for women and girls of various ages.

Meal size in ounces/portion

Age group 50th 95th 99th

1–2 yr old girls 1.5 4.4 5.6

3–5 yr old girls 2 6 8.5

6–8 yr old girls 2.5 6 10.2

9–14 yr old girls 2.8 7.3 10.2

15–18 yr old girls 3 9.5 20

Adult women 3 8 13.9

Source: U.S.EPA’s Exposure Factors Handbook (USEPA 1997).

Table 2A-1 (Chapter 2, Section 2.6, Appendix 2A-2) shows the estimated mercury doses for women and 

children who eat up to 20 ounces of fish daily and who weigh up to 220 pounds. Approximate age 

groups are provided for various body weights ranging from 10 to 220 pounds (4.5–100 kg). For example, 

for women who weigh 143 pounds (65 kg) and who eat 4 ounces of reef fish daily, the estimated dose is 

0.19 μg/kg/day. Similarly, for women who weigh 121 pounds (55 kg) and who eat 4 ounces of reef fish 

daily, the estimated mercury does is 0.22 μg/kg/day. These estimated doses exceed U.S.EPA’s RfD of 0.1 

μg/kg/day. The 99th percentile portion size is used to estimate the maximum dose for each age group. 

Doses are not calculated beyond this point and appear as black in Table 2A-1. Table 2-6 shows the 50th, 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 39

95th, and 99th percentile fish portion size for various age groups. Precision is difficult regarding what 

constitutes average fish consumption for Viequenses. Using information from Dr. Caro’s survey, a typical 

fish intake for an adult female might be three meals a week, with a portion size of 4 ounces and an 

average body weight of 55 kg (121 pounds). This person would have an estimated mercury dose of 0.094 

μg/kg/day, which is below U.S.EPA’s RfD of 0.1 μg/kg/day.

Estimated doses less than U.S.EPA’s RfD (0.1 μg/kg/day) are shown with a white background. Residents 

with these estimated doses are not at risk of harmful effects from mercury in fish. Estimated doses that 

exceed U.S.EPA’s RfD for residents who eat fish daily are shown in three shades of blue (light, medium, 

and dark). Women with estimated doses indicated as light blue (light gray in black and white) have a 

small increased risk of harming a developing fetus if they are pregnant. The risk is greater for those 

women with estimated doses indicated in medium blue. These estimated doses approach the dose of 

1.1 μg/kg/day identified by the National Academy of Science as a dose that results in a 5% increase in 

the incidence of abnormal scores on the Boston Naming Test (a picture-naming, vocabulary test). The 

NAS effect level is consistent with the range of 0.85 to 1.5 μg/kg/day identified by the U.S.EPA as the 

benchmark dose lower limit (BMDL05.)

Similarly, most of the estimated doses in children exceed U.S.EPA’s RfD as indicated by light, medium, 

and dark blue in Table 2A-1 (Chapter 2, Section 2.6, Appendix 2A-2). Young children with higher daily 

fish intake have estimated doses that exceed the effect level of 1.1 μg/kg/day. These doses are in dark 

blue. Whether children are as sensitive to the neurotoxic effects of mercury as is the fetus is uncertain. 

To be protective, U.S.EPA’s and FDA’s national fish advisory include a warning for children as well as 

women who are pregnant, who plan to become pregnant, and nursing mothers.

These conclusions about the risk of harmful effects are also somewhat uncertain; to know the exact 

dose that might cause harmful neurological effects in the fetus and in children is difficult. This 

uncertainty arises from limitations inherent in human studies and because a person’s susceptibility may 

vary. Finally, estimating the mercury dose that someone might receive is similarly uncertain. If residents 

eat more snapper and parrotfish, which are lower in mercury, their estimated dose of mercury will be 

lower; they are likely to be at lower risk of harmful effects or at no risk at all. If residents eat more grunt 

and hind, which are higher in mercury, their estimated dose of mercury will be higher and they could be 

at greater risk of harmful effects.

The conclusions and recommendations from ATSDR’s evaluation of fish and shellfish data appear at the 

end of this chapter (Section 2.3) and in Chapter 9 of this report.

2.2.6. Possible Mixtures Effects from Chemicals in Fish and Other Biota

In ATSDR’s 2003 Fish PHA, the concentrations of individual metals in Vieques reef fish were not at levels 

of health concern. In its evaluation of these fish data for this report, ATSDR concluded that mercury in 

fish is a concern for children and for the developing fetus in women who frequently eat large amounts 

of fish. Unfortunately, current science does not adequately support a robust analysis of multiple 

chemical exposures and their interactions. Debate continues in the scientific community about the best 

methods by which to evaluate exposure to a chemical mixture both from a single pathway and from 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 40

multiple, combined pathways. In addition, estimating combined doses from multiple pathways at 

Vieques is hampered by a lack of knowledge of the levels of chemicals residents are exposed to through 

various pathways (e.g., eating seafood, ingesting soil, drinking water, and breathing air). Because of this 

complexity and lack of knowledge, any additional risk from any possible, so-called mixtures effect 

assumed by residents eating seafood is likewise uncertain.

2.3. Conclusions and Recommendations

2.3.1. Conclusions

During ATSDR’s November 2009 meeting, several scientists raised concerns about mercury levels in fish. 

In particular, they were concerned that the conclusions in ATSDR’s 2003 Fish PHA were inconsistent with 

the 2004 U.S.EPA/FDA national advisory concerning mercury. Therefore, ATSDR reviewed its 2003 

conclusions and recommendations about mercury in fish from reefs surrounding Vieques. 

In its 2003 public health assessment regarding fish consumption, ATSDR used fish intake rates that 

focused on adults who ate 8 ounces of fish daily and who weighed 70 kg (or 154 pounds). Daily fish 

intakes rates for children were 4 ounces and children were assumed to weigh 16 kg (or 35 pounds). 

Estimated doses were compared with ATSDR’s MRL of 0.3 μg/kg/day, which was derived from an 

analysis of the Seychelles Island and Faroe Islands studies. In ATSDR’s evaluation as presented in this 

report, ATSDR used a broad range of daily fish intakes and body weights. Using information from 

U.S.EPA’s Exposure Factor Handbook, ATSDR assumed that daily fish intakes for adult women were as 

high as 14 ounces—the 99th percentile—and that women weigh as little as 46 kg (or 100 pounds). For 

children, ATSDR assumed that daily fish intakes were as high as 6 ounces for 1- to 2-year old children, 8 

ounces for 3- to 5-year old children, 10 ounces for 6- to 14-year old children, and 20 ounces for 15- to 

18-year old children. The highest intakes for children represent the 99th percentile portion size for the 

stated ages. In addition, ATSDR used the NAS’s recommendations and U.S.EPA’s Reference Dose (RfD) 

concerning mercury as well as human toxicity studies from the Faroe Islands. From its evaluation of 

mercury in Vieques fish, ATSDR reached these new conclusions:

1. ATSDR has identified mercury exposure from frequent consumption of marine seafood as a 

potential public health hazard. Women with a varied fish diet who typically eat more than 2 oz 

of fish every day have estimated mercury doses that exceed U.S.EPA’s chronic RfD. As portion 

size increases, the estimated doses approach the lowest level known to cause harmful effects to 

the developing fetus. ATSDR concludes that if these women are pregnant, their developing baby 

has a small increased risk of neurological effects later in life. The risk of harmful effects increases 

as portion size increases. Possible harmful effects identified from studies of non-Viequense 

children exposed in utero involve language, attention, and memory, and to a lesser extent 

visual/spatial and motor functions. 

2. Women who eat grunt or hind more frequently than other reef fish and who typically eat more 

than 2 oz of fish every day have estimated mercury doses two times higher than women who 

eat a varied fish diet. As portion size increases, the estimated doses approach or exceed the 

lowest level known to cause harmful effects in the developing fetus. ATSDR concludes that if 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 41

these women are pregnant, their developing baby has a small increased risk of neurological 

effects later in life. The risk of harmful effects increases as portion size increases. Possible 

harmful effects identified from studies of non-Viequense children exposed in utero involve 

language, attention, and memory, and to a lesser extent visual/spatial and motor functions.

3. Children with a varied fish diet who typically eat more than 0.5 oz of fish every day have 

estimated mercury doses that exceed U.S.EPA’s chronic RfD. These children have a small risk of 

neurological effects. But as portion size increases, the risk of harmful effects increases. 

Depending upon their age, children as young as 1 year who eat 3 to 4 ounces of fish every day 

have estimated doses that exceed doses known to cause neurological effects and have the 

greatest risk of harmful neurological effects. Possible harmful effects identified from studies of 

non-Viequense children exposed in utero involve language, attention, and memory, and to a 

lesser extent visual/spatial and motor functions.

4. Like women, children who eat grunt and hind more frequently than other reef fish have 

estimated doses two times higher than children who eat a varied fish diet. The estimated doses 

in these children exceed the doses associated with neurological effects.

5. Some uncertainty is associated with these findings because a person’s mercury response is itself 

somewhat uncertain. The uncertainty could be due to sex, genetics, health and nutritional 

status, or how mercury is handled in the body. In the three human studies that focused on 

mercury exposure from eating fish and seafood, the identification of the lowest-effect levels was 

uncertain. Estimating the mercury dose from eating reef fish was likewise uncertain, given that 

the dose could vary depending on the type, frequency, and quantity of fish eaten.

6. While ATSDR supports the U.S.EPA’s and the FDA’s national fish advisory, portions of the 

advisory do not apply to the Viequenses who rely heavily on local seafood. For example, the 

advisory discusses fish that Viequenses do not eat, such as pollock, catfish, and tilefish. In 

addition, the advisory recommends that if a local advisory is not available, people should not eat 

more 6 ounces of local fish and should not consume any other fish during the week. We include 

links to the advisory for informational use and we recommend an educational program about 

mercury in locally consumed fish. 

7. Residents need information so they can select local seafood lower in mercury over seafood 

higher in mercury. This will protect developing fetuses and young children from mercury in fish. 

For informational purposes only, the advisory and related information is available at: 

http://www.epa.gov/waterscience/fish/advice; http://www.fda.gov/Food/FoodSafety/ProductSpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm115662.h

tm, and Chapter 2, Section 2.7 of this report, Appendix 2A-3.

8. For the 104 fish samples collected from the marine areas near Vieques and from the commercial 

fish market, the average mercury level was 0.1 ppm and the range was nondetectable to 0.33 

ppm. The mercury levels detected in Vieques reef fish are similar to levels reported by the FDA 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 42

(FDA 2010). The mercury levels are in the low (0.02–0.2 ppm) to mid (0.2–0.6 ppm) mercury 

range identified by FDA in its recent risk and benefit assessment (FDA 2009). 

9. ATSDR also conducted a statistical analysis of the 2001 fish data and concluded the following:

a. Mercury detected in the seafood is higher in two fish families (grunt and hind) compared 

with other families sampled (e.g., parrotfish and snapper). The average mercury 

concentration in grunt and hind was higher than U.S.EPA’s 0.049 ppm screening level. In 

testing some of the hypotheses, ATSDR used the overall average of 0.1 ppm to determine 

which families of reef fish were likely to exceed the overall average. 

b. Mercury levels in parrotfish were statistically lower than U.S.EPA’s 0.049-ppm screening 

level and lower than the 0.1-ppm overall average. 

c. All snapper were lower than U.S.EPA’s 0.049 ppm screening value. But an insufficient 

number of snapper were collected to determine whether the average snapper-mercury level 

was statistically different from the U.S.EPA 0.049 ppm screening level. A sufficient number 

of snapper were collected to determine that the average mercury level is statistically lower 

than the 0.1-ppm overall average. 

10. Mercury is present in most seafood and is particularly high in some fish species and low in other 

species. While mercury was a component of the detonators of some bombs, only small amounts 

of mercury were introduced to the Vieques environment from this source. This conclusion is 

supported by the low mercury levels in LIA soils, which appear to be at naturally occurring 

levels. Mercury levels in fish in and around the LIA are most likely the result of the global 

reservoir of mercury circulating in the environment.

11. Statistical analysis showed that some fish and shellfish had higher levels of some metals and 

lower levels of other metals—iron, aluminum, copper, zinc, arsenic, barium, potassium, and 

selenium were all slightly higher. These metals are materials found in bombs and metal ships, 

suggesting possible localized contamination. But the levels were only slightly higher and the 

difference was only statistically significant when compared with a few other locations.

2.3.2. Recommendations

ATSDR recommends environmental and public health agencies and scientists consider the following:

1. People who frequently consume marine seafood should follow available fish advisories and 

fishing restrictions in Vieques. Maintain the fishing restrictions in the waters adjacent to the LIA.

2. Conduct a survey of Vieques residents to determine the types, frequency, and quantity of fish 

consumed.

3. Conduct additional risk assessments and statistical analyses using new information gathered 

from the previously recommended fish consumption survey.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 43

4. Collect and analyze additional fish samples from Vieques should the proposed survey and 

statistical analysis not provide sufficient public health information. Collect sufficient fish samples 

to allow analysis by species and by location.

5. Develop an educational program about mercury in fish that incorporates local habits and 

information about Viequenses’ seafood consumption. Benefits accrue to the developing fetus 

with maternal intake of nutrients in seafood (FDA 2009) that can outweigh the concomitant 

intake of small amounts of mercury. The goal of this site-specific educational program should be 

to educate Viequenses about the benefits of eating seafood so they can choose fish lower in 

mercury and still maintain their healthy dietary customs of consuming local seafood.

2.4. References

[ATSDR] Agency for Toxic Substances and Disease Registry. 1999 March. Toxicological profile for mercury 

(update). Atlanta: US Department of Health and Human Services, Public Health Service.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2007 March. Toxicological profile for arsenic 

(update). Atlanta: US Department of Health and Human Services, Public Health Service.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2004. Guidance Manual for the Assessment 

of Joint Toxic Action of Chemicals Mixtures. Atlanta: US Department of Health and Human Services, 

Public Health Service. Available at: http://www.atsdr.cdc.gov/interactionprofiles/ipga.html, accessed 

April 2, 2010.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2005. Public Health Assessment Guidance 

Manual (Update). Atlanta: US Department of Health and Human Services, Public Health Service; January.

Bloom 1992. On the chemical form of mercury in edible fish and marine invertebrate tissue. Can J Fish 

Aquat Sci 49(5):1010–17.

Burton DT, Cooper KR, Goodfellow WL Bioconcentration, Elimination and Metabolism of Picric and 

Picramic Acid in Freshwater Fish and Estuarine Bivalves. Arch Environ Contam Toxicol 1983 

Oct;41(3):308-18.

Burton DT, Goodfellow WL, Cooper KR Uptake, elimination, and metabolism of14C-picric acid and14Cpicramic acid in the American oyster (Crassostrea virginica) Arch Environ Contam Toxicol 1984 V 13, No 

6, November, 1984.

Caro DA, Nazario M, Diaz N. 2000. Toxicological Survey of Heavy Metals in Fish Populations, Vieques 

Island. Universidad Metropolitana, School of Environmental Matters. June 2000.

Cooper KR, Burton DT, Goodfellow WL, Rosenblatt DH. 1984. Bioconcentration and metabolism of picric 

acid and picramic acid in rainbow trout. J of Toxicology and Environmental Health 14:731-747.

Crump KS, Kjellstrom T, Shipp A, et al. 1998. Influence of prenatal exposure upon scholastic and 

psychological test performance: Benchmark analysis of a New Zealand Cohort. Risk Anal 18(6):701–13.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 44

Davidson PW, Myers GJ, Cox C, et al. 1998. Effects of prenatal and postnatal methylmercury exposure 

from fish consumption on neurodevelopment: Outcomes at 66 months of age in the Seychelles child 

development study. JAMA 280(8):701–07.

Davidson PW, Myers GJ, Cox C, Wilding FE, Shamlaye CF, et al. 2006. Methylmercury and 

neurodevelopment: longitudinal analysis of the Seychelles child development cohort. Neurotoxicol 

Teratol 28:529–35.

Debes F, Budtz-Jorgensen E, Weihe P, White RF, Grandjean P. 2006. Impact of prenatal methylmercury 

exposure on neurobehavioral function at age 14 years. Neurotoxicol Tereatol 28:363–75.

[FDA] Food and Drug Administration. 2004. What you need to know about mercury in fish and shellfish: 

2004 EPA and FDA advice for women who might become pregnant, women who are pregnant, nursing 

mothers, and young children. Available at: http://www.fda.gov/Food/FoodSafety/ProductSpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm115662.htm

[accessed 2009 Dec 18]. 

[FDA] Food and Drug Administration. 2010. Mercury concentrations in fish: FDA monitoring program. 

http://www.fda.gov/Food/FoodSafety/ProductSpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm191007.htm, and 

http://www.fda.gov/Food/FoodSafety/ProductSpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm115644.htm

[accessed 2010 December 13].

[FDA] Food and Drug Administration. 2009. Report of quantitative risk and benefit assessment of 

consumption of commercial fish, focusing on fetal neurodevelopmental effects (measured by verbal 

development in children) and on coronary heart disease and stroke in the general population, January 

15, 2009. Available at: http://www.fda.gov/Food/FoodSafety/ProductSpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm088794.htm. 

[accessed 2009 Nov 27]. 

Grandjean P, Weihe P, White RF, Debes F, et al. 1997. Cognitive deficit in 7-year-old children with 

prenatal exposure to methylmercury. Neurotoxicol Teratol 19:417–28.

Greib TM, Driscoll CT, Gloss SP, et al. 1990. Factors affecting mercury accumulation in fish in the upper 

Michigan peninsula. Environ Toxicol Chem 9:919–30.

Hélène DM, Augagneur S, Budzinski H, Mora P, Narbonne J, Garrigues P. 2003. Microcosm tributylin 

bioaccumulation and multibiomarker assessment in the blue mussel, Mytilus edulis. Environ Toxicology 

and Chemistry 22:2679–686.

Houston JG and Lutufo GR. 2005. Dietary exposure of fathead minnows to the explosives TNT and RDX 

and the pesticide DDT using contaminated invertebrates. Int J of Environ Res Public Health 2(2):286-292.

Lotufo GR and Lydy J. 2005. Comparative toxicokinetics of explosive compounds in sheepshead 

minnows. Env Contam and Toxicology 49:206-214.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 45

Lotufo GR, Lydy J, Wild W. Toxicokinetics and toxicity of explosive compounds in fish. Presented at: 

Society of Env Toxicology and Chemistry Conference; 2005.

Mukhi S, Pan X, Cobb GP, Patiño R. 2005. Toxicity of hexahydro-1,3,5-trinitro-1,3,5-triazine to 3 larval 

zebrafish (Danio rerio). Chemosphere 2. 

Mukhi S and Patiño R. 2008. Effects of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in zebrafish: General 

and reproductive toxicity. Chemosphere 72:726–732.

Myers GJ, Davidson PW, Cox C, Shamlaye CF, Palumbo D et al. 2003. Prenatal methylmercury exposure 

from ocean fish consumption in the Seychelles child development study. The Lancet 361:1686–692.

Myers GJ, Thurston SW, Pearson AT, Davidson PW et al. 2009. Postnatal exposure to methylmercury 

from fish consumption: a review and new data from the Seychelles Child Development Study. 

Neurotoxicol 30;338–49.

Nipper M, Carr RS, Biedenbach JM, Hooten RL, Miller K, Saepoff S. 2001. Development of marine toxicity 

data for ordinance compounds. Environ Contam Toxicology 41(3):308-313.

Nipper M and Carr RS. 2005. Ecological fate and transport of explosives and related compounds. 

Presented at: Society of Env Toxicology and Chemistry Conference; 2005.

[NOAA] National Oceanic and Atmospheric Administration 2010. An ecological characterization of the 

marine resources of Vieques, Puerto Rico. Available at:

http://ccma.nos.noaa.gov/ecosystems/coralreef/vieques/

[accessed 2011 June 13 ].

[NRC] National Research Council. 2000. Toxicological Effects of Methymercury. Washington (DC): 

National Academy of Sciences, National Research Council. Pubs: National Academy Press. 

Ownby DR, Belden JB, Lotufo GR, Lydy M. 2005. Accumulation of TNT in aquatic organisms: Part 1 –

Bioconcentration and distribution in channel catfish (Ictalurus punctatus). Chemosophere 58(9):1153-

1159.

Peshut PJ, Morrison RJ, Brooks BA. 2008. Arsenic speciation in marine fish and shellfish from American 

Samoa. Chemosphere 71(3);484-92.

Rodríguez Sierra CJ, Jimenez B. 2002. Trace metals in striped majarra fish (Diapterus plumier) from 

Puerto Rico. Marine Pollution Bulletin 44;1039-1045.

Risher J. 2010. March 23rd e-mail from John Risher, ATSDR/DTEM to Dr. David Mellard, ATSDR/DHAC.

Rosen G and Lotufo GR. 2007. Bioaccumulation of explosive compounds in the marine mussel, Mytilus 

galloprovinciallis. Ecotoxicology and Environmental Safety 68:237-245.

Rosen G and Lotufo GR. 2005. Toxicity and fate of two munitions constituents in spiked sediment 

exposures with the marine amphipod, Eohaustorius estuarius. Env Toxicology and Chemistry 

24(11):2887–2897.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 46

Rosen G and Lotufo GR. 2007. Toxicity of explosive compounds to the marine mussel, Mytilus 

galloprovincialis, in aqueous exposures. Ecotoxicology and Environmental Safety 68:228–236.

State of California. 2009. Draft health advisory: safe eating guidelines for fish from Lake Sonoma 

(Sonoma County) and Lake Mendocino (Mendocino County) August 2006. Available at: 

www.oehha.ca.gov/fish/so_cal/pdf_zip/DSonomaMendo081706.pdf [2009 Nov 25].

[USEPA] US Environmental Protection Agency. 1997. Exposure factors handbook; August.

[USEPA] US Environmental Protection Agency. 2000. Guidance for assessing chemical contaminant data 

for use in fish advisories. Fish sampling and analysis. Third Edition, Volume 1. Available at: 

http://www.epa.gov/waterscience/fish/technical/guidance.html [accessed 2009 Nov 25].

[USEPA] U.S. Environmental Protection Agency/Environmental Response Team (EPA/ERT). 2001. Field 

Data Summary, Vieques Fish Assessment, Vieques, Puerto Rico. November 8, 2001.

[USEPA] US Environmental Protection Agency. 2004. Consumption advice, joint federal advisory for 

mercury in fish. Available at: http://www.epa.gov/waterscience/fish/advice/factsheet.html [accessed 

2009 Dec 18]. 

[USEPA] US Environmental Protection Agency. Methylmercury, IRIS Database. US Environmental 

Protection Agency, Washington, DC. Available at: http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?IRIS

[accessed 2009 Dec 18].

Williams P, Porter J. 1999. Press Release from University of Georgia. Available at: 

www.uga.edu/news/newsbureau/releases/1999releases/porter_rico.html Dec 13, 1999 [accessed 2011 

Feb 16).

Yost SL, Pennington JC, Brannon JM, Hayes CA. 2007. Environmental process descriptors for TNT, TNTrelated compounds and picric acid in marine sediment slurries. Marine Pollution Bulletin 54:1262–66.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 47

2.5. Appendix 2A-1: Statistical Analysis of ATSDR Fish Data

2.5.1. Addressing the Statistical Tests and Sample Numbers

Any investigation has strengths and weaknesses. The strengths of the 2001 sampling supported by 

ATSDR were 

 It repeated the analysis of metals in market fish conducted by the Universidad Metropolitana, 

School of Environmental Matters (Caro et al. 2000). 

 It provided previously unavailable, specific information about fish. Such information included

measurements of explosive compounds in fish, measurements of contaminants in fish captured 

on specific reefs around the island (including reefs with visible signs of military presence), and 

measurements of contaminants in shellfish captured on and around the island. 

The limitations were 

 By collecting only larger specimens of the popular reef species, the average concentrations 

might have been biased high, which might have resulted in a mercury overestimate. 

 Because larger fish were targeted and the reefs had only a few larger species, fish within the 

same family had to be combined to provide statistical significance. Consequently, these data 

could not establish differences in concentration between most species within a family. Fish 

within a family were grouped to provide sufficient number to represent each family at a 

sampling location. Although this was adequate to represent the concentrations of most metals 

in the families, more appropriate ways to address mercury were available. We determined that 

mercury concentrations were highly dependent on species within a family. For example, white 

grunt had lower mercury concentrations than the rest of the fish in the grunt family, and red 

hind had lower mercury concentrations than others in the hind family.

2.5.2. Sample Design

The original sample design did not focus only on mercury, but mercury was included. ATSDR and U.S.EPA

proposed a sampling strategy to 1) evaluate many metals and explosive chemicals in fish, and 2) 

compare chemicals in fish caught in the various reefs with fish purchased at the market (USEPA 2001). 

From each location, the specimens collected were approximately the same size. The School of 

Environmental Matters collected 52 fish of varying sizes, with little variation in results. Each of these 

datasets provided unique and meaningful information about mercury and other metals. 

Statistical tests confirmed sufficient fish for numerous evaluations. U.S.EPA provided statistical tests to 

compare fish by location and by family for all metals (USEPA 2001), and ATSDR provided statistics to 

compare fish family with health-related concentrations for mercury. A summary of ATSDR’s testing is 

provided below.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 48

2.5.3. Summary of Statistics for Health-Related Hypothesis Testing

Hypothesis tests were designed to determine whether mean mercury concentrations were above or 

below 0.1 ppm and above or below 0.049 ppm. Figure 2A-1 of total mercury in fish by family illustrates 

many of the results of the statistical tests.

Figure 2A-1. Total mercury in fish by family

Blue squares represent concentrations for individual fillet sample. The horizontal dotted line at 0.049 ppm (close to 

the 0.05 label) connotes the EPA screening value for subsistence populations and the horizontal dotted line at 0.1 

ppm connotes a site-specific methylmercury value calculated using ATSDR’s 2001 fish data.

A statistical analysis of the data supports the following conclusions:

1. Most of the goatfish, hind, and grunt were above the 0.049 ppm level;

a. The mean goatfish concentration of 0.0797 ppm was statistically higher than 0.049 ppm;

b. The mean hind concentration of 0.116 ppm was statistically higher than 0.049 ppm;

c. The mean grunt concentration of 0.185 ppm was statistically higher than 0.049 ppm;

2. Many of the hind and grunt were above the 0.1 ppm level.

a. But the mean hind concentration of 0.116 ppm was not statistically different than 0.1 ppm;

b. Follow-up review of the species shows that red hind are lower (with a mean concentration 

of 0.091 ppm—also not statistically different from 0.1 ppm)

c. The mean grunt concentration of 0.185 ppm was statistically higher than 0.1 ppm; 

d. Follow-up review of the species shows that Bluestriped grunt and French grunt were higher 

with mean concentrations of 0.22 ppm (each) and that white grunt averaged 0.098 ppm

(therefore, white grunt were not statistically different from 0.1 ppm)

3. Many of the snapper and goatfish were between the two levels (i.e., 0.049 ppm and 0.1 ppm): 

Total Mercury Concentrations 

in Various Species

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

Fiddler

LandCrab

Conch

Lobster

Trunkfish

Parrot

Snapper

Goatfish

Hind

Grunt

Concentration (mg/kg-wet)
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 49

a. The snapper concentration of 0.0478 ppm was not statistically different from 0.049 ppm, 

but was statistically lower than 0.1 ppm;

b. The mean goatfish concentration of 0.0797 ppm was statistically higher than 0.049, but not 

statistically different from 0.1 ppm;

4. The remaining fish families were below the 0.049 ppm level (many of those results were 

statistically significant):

a. The mean lobster concentration of 0.0317 ppm was statistically lower than 0.049 ppm.

b. The highest mercury concentration in 25 parrotfish was 0.0231 ppm, less than half of the 

0.049 ppm screening level. Because mercury was not detected in most samples, the 

concentrations were not normally distributed; we therefore performed nonparametric tests 

using the median. The median of 0.00767 ppm has 95% confidence limits of 0.00747 and 

0.00801 ppm, with a coverage of 95.7%, lower than 0.049 ppm.

c. The highest mercury concentration in 11 composite land crab samples was 0.0287 ppm—

less than the 0.049-ppm screening level. The concentrations were not normally distributed; 

mercury was not detected in many samples. We therefore identified that the median 

0.00823 ppm (with its 95% confidence limits of 0.00725 and 0.0216 ppm and 96.1% 

coverage) was lower than 0.049 ppm.

d. The highest mercury concentration in 20 conch samples was 0.0486 ppm, lower than 0.049 

ppm. The conch concentrations were not normally distributed—mercury was not detected 

in many samples. We therefore found that the median 0.008277 ppm (with its 95% 

confidence limits of 0.00803 and 0.0179 ppm and 95.9% coverage) was well below 0.049 

ppm.

e. Four composite fiddler crab samples were normally distributed, with a mean concentration 

of 0.0077 ppm—statistically lower than 0.049 ppm.

f. We had only one trunkfish sample—insufficient for statistical analysis.

We could make more specific conclusions for families or species. 

2.5.4. Testing Limitations

Testing of the thresholds had a high bias: larger fish were used, and total mercury was used to represent 

methylmercury. More samples in some locations would provide stronger results. But to collect enough 

samples for the test levels chosen (0.049 and 0.1 ppm) could be cost prohibitive, as some families had 

averages very close to those levels. 

2.5.4.1. Summary of Statistics for Location Testing

Statistical analyses were conducted on the mercury (and other metals) levels in fish and invertebrate 

tissues to determine whether the locations were statistically different (USEPA 2001). Tissue from hind, 

grunts, parrotfish, snappers, conch, and land crabs were included in the analyses. Because of the limited 

numbers collected at most sampling locations, fiddler crabs, goatfish, and lobster were not tested. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 50

The mercury statistical test found high influence of species and size. Even with these influences, the 

range of concentrations within families was relatively small. Thus any differences by location are hard to 

determine. Because the range of mercury concentrations was small and the influence of species and size

was large, we cannot predict the number of samples needed to determine any differences between the 

levels found in the fish at each location. Further statistical tests are provided below.

2.5.5. Results of the Tests (Mercury focus)

A multivariate analysis of variance (MANOVA) was computed for mercury (and other metals). Individual 

analysis of variance (ANOVA) results indicated a statistical significance between several metals at several 

locations. But for mercury, little statistical difference appeared between the locations. Table C1 in 

Appendix C of U.S.EPA (2001) includes a complete summary of all comparisons between locations, 

parametric and nonparametric, for all families. The following is an abbreviated list of the summary of 

the mercury statistic tests provided by U.S.EPA in Appendix C of U.S.EPA (2001):

 Hind: A MANOVA was computed for mercury. Individual ANOVA results indicated a statistical 

significance between locations for other metals, but not for mercury. The statistical reports for 

hind are listed under “grouper” in U.S.EPA (2001) p C3.1. 

 Grunt: A MANOVA was computed for mercury. Individual ANOVA results indicated a statistical 

significance between locations for some metals, but not for mercury. 

 Snapper: A MANOVA was computed for mercury. Individual ANOVA results indicated a statistical 

significance between locations for some metals, but not for mercury. 

 Parrotfish: Kruskal-Wallis’s nonparametric comparison of the locations indicated no significant 

difference (p<0.05) for mercury in comparisons between locations. 

 Conch: Mercury at Esperanza was higher than the LIA North, LIA South, and the West End. 

Kruskal-Wallis’s nonparametric comparison of the locations resulted in significant probability 

values (p<0.05) from comparisons between locations for mercury. Tukey’s multiple comparisons 

on the ranks resulted in two distinct patterns for mercury: LIA-North (1), LIA-South (2), and the 

West End (6) were grouped together; Esperanza (3) was grouped separately. 

Land Crabs: Because more than 50% of mercury results were below the detection level, they 

were evaluated using nonparametric methods. Nonparametric testing indicated no significant 

difference between mercury levels at the locations.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 51

Table C1 from U.S.EPA’s report (USEPA 2001) for locations 1 through 6.

2.5.6. Testing Limitations

Because of peer-review comments, we performed additional tests. Because the grunt family averaged 

higher than 0.1 ppm, we tested to determine whether all grunt species were higher. Four French grunt 

were caught near the west end and nowhere else; all were over 0.1, with the lowest sample having 0.14 

ppm and the 95% confidence interval being 0.13 ppm. These French grunt were much smaller than the 

other species of grunts. French grunt, even at full size, are small and tend to forage more near sand than 

near grasses at night when they leave the reef, resulting in different exposures from other grunt. 

Because French grunt had relatively high mercury levels for their size, they introduce a bias into the 

grunt family. This reduced our ability to compare all grunt at all reefs. Bluestriped grunt were caught at 

three reefs, North LIA, South LIA, and Esperanza, with similar averages (between 0.21-0.24 ppm). 

Furthermore, White grunt were statistically lower than Bluestriped grunt and French grunt. The market 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 52

only had white grunt for the investigation. We found no statistical difference between the Bluestriped

grunt at the two LIA locations compared with those caught at Esperanza.

In Chapter 2, Section 2.2.2 we discussed the hind family as one case where it appeared that a location 

(location 1) had different (in this case lower) concentrations than other locations. We also mentioned 

additional statistical tests to determine other reasons for location 1 having lower levels. Looking into 

this family, we want to compare other species factors and to determine whether weight could have 

influenced the results.

We had sufficient samples within the hind family only to evaluate further the red hind and the rock hind. 

The red hind from the market, from Isabel Segunda, and from the North LIA averaged less than the rock 

hind from Esperanza and the South LIA (from Table 2-5). The three rock hind from the west end had the 

lowest average mercury levels for that species (0.057 ppm). Rock hind were found at two reefs, South 

LIA (averaging 0.13 ppm) and Esperanza (averaging 0.16 ppm). After accounting for species differences, 

we can determine whether weight influences the concentration by looking at concentrations within one 

species. Figure 2A-2 is a scatterplot of all the rock hind weights compared with their mercury 

concentrations.

Figures 2A-2a and 2A-2b. Weight (in oz) vs. mercury concentration (ppm)

The graphs suggest a relationship between fish size and mercury concentration. This was not evident in 

the fish Caro collected. Because ATSDR intentionally selected larger fish, the size variation is insufficient 

to make this comparison for all fish. 

From the mercury tests, we concluded that only conch showed statistical differences by location. Those 

differences were that conch on the LIA-North, the LIA-South, and the West End had statistically less 

mercury than the conch collected in Esperanza. Even the Esperanza conch, however, were below 

screening levels. 

0

5

10

15

20

25

30

35

0.05 0.1 0.15 0.2 0.25

Rock Hind

0

5

10

15

20

25

30

35

0.02 0.07 0.12 0.17

Red Hind
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 53

2.5.7. Mercury: Three Human Studies and U.S.EPA’s Reference Dose

Several human studies have evaluated the neurological effects of methylmercury exposure in children. A 

long-term human study of children from the Faroe Islands, a small group of islands in the North Atlantic 

Ocean affiliated with Denmark, began in 1986 and focused on children born to women who lived on the 

islands. This population relies heavily on seafood and whales as a protein source. The investigators used 

various tests that monitor child development. They concluded that at birth, cord blood mercury levels in 

the mother were associated with harmful effects in children at age 7 years involving language, attention,

and memory, and to a lesser extent visual/spatial and motor functions (Grandjean et al 1997). Follow-up 

studies at age 14 years showed similar findings (Debes et al 2006).

In 1978, New Zealand was the site of another human study. It focused on 61 children who were exposed 

in utero to high mercury levels that resulted from their mother’s consumption of four or more fish meals 

a week. If the authors omitted one outlier, the data showed a decrease in children’s intelligence 

quotient (IQ) at age 6 with increasing exposure to methylmercury as measured by their mother’s hair 

mercury levels at birth (Crump 1998). The third study came from the Republic of Seychelles, where 85% 

of the population relied on local seafood for protein. Average ocean fish consumption in this population 

was 12 meals a week (Davidson 1998). The Seychelles study initially did not find harmful effects in 

children as they grew older. In one recent publication, the investigators reported that two of 21 

endpoints (one positive and one negative) were associated with prenatal methylmercury exposure. The 

authors stated that these outcomes were probably due to chance. They concluded that their data did

not support a neurodevelopment risk from prenatal methylmercury exposure from eating fish (Myers 

2003). In another paper, the authors reported that they found several associations between postnatal 

methylmercury exposure and children’s developmental endpoints. However, the investigators 

concluded that no consistent pattern of associations emerged to support a causal relationship (Myers 

2009). In some cases in which several tests were used to evaluate a single domain, and only one of those 

tests was positive, the Seychelles investigators did not believe they could base a firm conclusion on only 

one of several tests for that domain. Rather, they believed that if a domain was adversely affected, more 

than one test should show it (Risher 2010). 

More information about the harmful effects of methylmercury is available in ATSDR’s Toxicological 

Profile for Mercury (ATSDR 1999).

U.S.EPA developed a methylmercury Reference Dose using a mathematical model that estimated a 5% 

adverse response in children for neurological effects.15 Using the Faroe Islands study, U.S.EPA concluded

that the methylmercury concentration in maternal cord blood that caused a 5% adverse response in 

children ranged from 46 to 79 ppb. This methylmercury concentration in maternal blood equated to a 

range of 0.8 to 1.5 μg methylmercury per kilogram per day (μg /kg/day) as a dietary intake. The doses 

were divided by an uncertainty factor of 10 to arrive at the Reference Dose of 0.1 μg/kg/day. The 

 

15 More precisely, U.S.EPA estimated the lower 95th confidence limit of the concentration of methylmercury in 

maternal blood that gave a 5% response for neurological effects in offspring at 7 years of age. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 54

U.S.EPA’s approach is consistent with the approach used by the National Academy of Sciences. The NAS 

recommended that U.S.EPA use the Faroe Islands Study and 58 ppb methylmercury in cord blood for 

deriving its health guideline (NRC 2000). U.S.EPA’s methods for deriving the agency’s RfD are described 

in detail at http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?IRIS (IRIS 2009). 

The National Academy of Sciences concluded that some risk is possible regarding anticipated harmful 

effects in children exposed in utero to 58 ppb methylmercury in cord blood. The cord blood 

concentration of 58 ppb methylmercury equates to 12 ppm methylmercury in maternal hair (NRC 2000).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page 55 

2.6. Appendix 2A-2. Estimated Doses in Residents from Eating Vieques Fish 

Table 2A-1. Estimated mercury dose for women and children of various body weights from eating Vieques reef fish. + 

Approximate Age Body Wt lbs Body Wt kg Estimated Mercury Dose in μg/kg/day 

18 yr and older A 

 

D 

 

U 

 

L 

 

T 

 

S 

 220 100 0.02 0.03 0.06 0.09 0.12 0.15 0.18 0.21 0.24 0.30 0.36 0.42 

18 yr and older 198 90 0.02 0.03 0.07 0.10 0.13 0.17 0.20 0.24 0.27 0.34 0.40 0.47 

18 yr and older 176 80 0.02 0.04 0.08 0.11 0.15 0.19 0.23 0.26 0.30 0.38 0.45 0.53 

18 yr and older 154 70 0.02 0.04 0.09 0.13 0.17 0.22 0.26 0.30 0.35 0.43 0.52 0.60 

18 yr and older 143 65 0.02 0.05 0.09 0.14 0.19 0.23 0.28 0.33 0.37 0.46 0.56 0.65 0.74 0.93 

17 yr and older C 

 

 

H 

 

 

I 

 

 

L 

 

 

D 

 

R 

 

E 

 

N 

132 60 0.03 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.50 0.60 0.71 0.81 1.01 

16 yr and older 128 58.1 0.03 0.05 0.10 0.16 0.21 0.26 0.31 0.36 0.42 0.52 0.62 0.73 0.83 1.04 

15 yr and older 121 55.1 0.03 0.05 0.11 0.16 0.22 0.27 0.33 0.38 0.44 0.55 0.66 0.77 0.88 1.10 

14 yr and older 121 54.8 0.03 0.06 0.11 0.17 0.22 0.28 0.33 0.39 0.44 0.55 

13 yr and older 112 50.9 0.03 0.06 0.12 0.18 0.24 0.30 0.36 0.42 0.47 0.59 

12 yr and older 102 46.4 0.03 0.07 0.13 0.20 0.26 0.33 0.39 0.46 0.52 0.65 

11 yr 

 

92 41.8 0.04 0.07 0.14 0.22 0.29 0.36 0.43 0.51 0.58 0.72 

10 yr 79 36.1 0.04 0.08 0.17 0.25 0.33 0.42 0.50 0.59 0.67 0.84 

9 yr 70 31.9 0.05 0.09 0.19 0.28 0.38 0.47 0.57 0.66 0.76 0.95 

8 yr 61 27.9 0.05 0.11 0.22 0.32 0.43 0.54 0.65 0.76 0.87 1.08 

7 yr 55 25 0.06 0.12 0.24 0.36 0.48 0.60 0.73 0.85 0.97 1.21 

6 yr 49 22.1 0.07 0.14 0.27 0.41 0.55 0.68 0.82 0.96 1.09 1.37 

5 yr 43 19.6 0.08 0.15 0.31 0.46 0.62 0.77 0.93 1.08 1.23 

4 yr 37 17 0.09 0.18 0.36 0.53 0.71 0.89 1.07 1.24 1.42 

3 yr 33 14.9 0.10 0.20 0.41 0.61 0.81 1.01 1.22 1.42 1.62 

2 yr 29 13 0.12 0.23 0.46 0.70 0.93 1.16 1.39 

1 yr 24 10.8 0.14 0.28 0.56 0.84 1.12 1.40 1.68 

< 1 yr 19.4 8.8 0.17 0.34 0.69 1.03 1.37 1.72 2.06 

< 1 yr 9.9 4.5 0.34 0.67 1.34 

 

fish kg/day 0.014 0.028 0.057 0.085 0.113 0.142 0.170 0.198 0.227 0.284 0.340 0.397 0.454 0.567 

fish oz/day 0.5 1 2 3 4 5 6 7 8 10 12 14 16 20

+ Men with the same weight and fish intake have the same estimated dose as women. *These estimated doses are for teenagers 15 to 18 years 

who have a 99th percentile fish-meal portion of 20 ounces. The 99th percentile fish meal portion for adult women is 14 ounces. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page 56 

2.7. Appendix 2A-3. The Joint U.S.EPA and FDA National Fish Advisory

What You Need to Know About Mercury in Fish and Shellfish, March 2004: 

2004 EPA and FDA Advice for Women Who Might Become Pregnant, Women Who Are Pregnant, Nursing 

Mothers, and Young Children

Fish and shellfish are an important part of a healthy diet. Fish and shellfish contain high-quality protein 

and other essential nutrients, are low in saturated fat, and contain omega-3 fatty acids. A well-balanced 

diet that includes a variety of fish and shellfish can contribute to heart health and children's proper 

growth and development. So, women and young children in particular should include fish or shellfish in 

their diets due to the many nutritional benefits. 

However, nearly all fish and shellfish contain traces of mercury. For most people, the risk from mercury 

by eating fish and shellfish is not a health concern. Yet, some fish and shellfish contain higher levels of 

mercury that may harm an unborn baby or young child's developing nervous system. The risks from 

mercury in fish and shellfish depend on the amount of fish and shellfish eaten and the levels of mercury 

in the fish and shellfish. Therefore, the Food and Drug Administration (FDA) and the Environmental 

Protection Agency (EPA) are advising women who may become pregnant, pregnant women, nursing 

mothers, and young children to avoid some types of fish and eat fish and shellfish that are lower in 

mercury. 

By following these three recommendations for selecting and eating fish or shellfish, women and young 

children will receive the benefits of eating fish and shellfish and be confident that they have reduced 

their exposure to the harmful effects of mercury. 

1. Do not eat shark, swordfish, king mackerel, or tilefish because they contain high levels of 

mercury. 

2. Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in 

mercury. 

a. Five of the most commonly eaten fish that are low in mercury are shrimp, canned light tuna, 

salmon, pollock, and catfish. 

b. Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light 

tuna. So, when choosing your two meals of fish and shellfish, you may eat up to 6 ounces 

(one average meal) of albacore tuna per week. 

3. Check local advisories about the safety of fish caught by family and friends in your local lakes, 

rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per 

week of fish you catch from local waters, but do not consume any other fish during that week. 

Follow these same recommendations when feeding fish and shellfish to your young child, but serve 

smaller portions. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 57

3. Biomonitoring

3.1. Introduction to Biomonitoring.................................................................................................. 58

3.2. Assessment of Available Vieques Human Biomonitoring Studies Data ................................... 59

3.3. Strengths and Limitations of Human Biomonitoring for Vieques ............................................ 62

3.4. The Special Case of Hair Analysis for Metals and Other Elements........................................... 62

3.4.1. ATSDR’s 2001 Hair Panel ............................................................................................... 62

3.4.2. Current Status of Hair Analysis Validity......................................................................... 63

3.5. Conclusions and Recommendations......................................................................................... 64

3.5.1. Conclusions.................................................................................................................... 64

3.5.2. Recommendations......................................................................................................... 65

3.6. References................................................................................................................................ 65

3.7. Appendix 3-A. Biomonitoring ................................................................................................... 68

3.7.1. Vieques, Puerto Rico-Related Human Biomonitoring Study Summaries...................... 68

3.7.2. PRDOH Biomonitoring Study ......................................................................................... 68

3.7.3. PRDOH Study, Phase 2................................................................................................... 79

3.7.4. PRDOH Findings............................................................................................................. 80

3.7.5. PRDOH Actions Taken After Phase 1 and Phase 2......................................................... 82

3.7.6. PRDOH’s Suggested Follow-up Activities....................................................................... 82

3.7.7. Investigations by Dr. Carmen Ortiz Roque .................................................................... 83

3.7.8. Summary of Dr. Ortiz Roque 2002 Unpublished Manuscript........................................ 84

3.7.9. Investigations by Dr. Carmen Colón de Jorge................................................................ 87

3.7.10. Investigations by Dr. Carlos Rodríguez Sierra................................................................ 93

3.8. Appendix 3-B. Biomonitoring ................................................................................................... 95

Chapter 3 Summary

The following chapter describes and evaluates the available biomonitoring studies of Vieques 

residents. These studies were conducted since 1999 by Puerto Rican scientists and physicians or by 

the Commonwealth’s Department of Health. They consist of measurement of various metals in 

residents’ blood, urine, hair, or feces. Data from these studies reported elevated levels of some 

metals in residents’ blood, urine, or hair. While some of these elevated levels might be explained by 

cigarette use, seafood consumption, or hair dyes, they did not account for all the elevated levels. 

These studies were unable to investigate each person’s environment to identify the metals’ source 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 58

for those residents who had excessive levels in hair, urine, or blood. The PRDOH study came closest 

to identifying possible sources but acknowledges an inability to identify the source or sources for all 

residents with excessive metals exposure. 

Viequenses may be exposed to mercury in fish and cadmium in pigeon peas. These exposures may 

warrant additional environmental investigations, such as sampling locally grown produce for 

cadmium and gathering more information about fish consumption and possibly mercury in fish. The

information could be used to decide whether to undertake human testing for mercury and cadmium

in blood or urine. If other environmental exposures are identified, additional human biomonitoring 

investigations may be considered. More detailed information about ATSDR’s recommendations 

concerning fish and locally grown produce can be found in Chapter 2, Section 2.3.2 and Chapter 5, 

Section 5.3.2, respectively. Although ATSDR is not recommending a comprehensive, systematic

biomonitoring effort at this time, public health officials could consider a limited and focused human 

biomonitoring investigation following the release of this report. If a biomonitoring investigation is 

conducted, it should include a comparison group from mainland Puerto Rico. If requested, 

CDC/ATSDR subject matter experts will provide technical assistance and support to PRDOH in 

planning and conducting such an investigation.

Viequenses who remain concerned about exposure to mercury, cadmium, other metals, or 

metalloids should consult their healthcare provider to discuss the need for and cost of testing. A 

qualified laboratory should do the testing and analysis. CDC/ATSDR can provide a list of qualified 

laboratories that can perform the tests. And if requested , CDC/ATSDR can provide information to 

healthcare providers about tests for metals in biologic samples. 

3.1. Introduction to Biomonitoring

Biomonitoring is the measurement of metals or chemicals in a biological matrix such as blood, urine, or 

hair. It can sometimes be a useful method of evaluating environmental chemical exposure in people. 

Biomonitoring examples include measuring lead in blood, cadmium in urine, and mercury in hair. The 

concentration of environmental chemicals in a biological matrix may allow assessment of excessive 

exposure. In some cases, the levels of environmental chemicals could be predictive of the risk of harmful 

effects occurring in the population. Depending on the chemical, biomonitoring studies can provide 

insight into a population’s exposure over the previous days, weeks or months, or even years. Scientists 

usually use biomonitoring to assess populations at risk for exposure (e.g., average exposures or the 

prevalence of unusually high exposures). Less often, biomonitoring can be useful in assessing the 

exposure of a single person.

But like all exposure assessments, biomonitoring has limitations and requirements. These fall into five

categories: 

Many chemicals are not measureable with current technology. 

Measurements require defined precision and accuracy to be applicable. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 59

Proper timing and collection techniques are required. In fact, they are essential to 

interpretation, appropriate comparison, or identification of reference groups. 

Although biomonitoring can assist in exposure assessment, the toxicological significance of 

biomonitoring results is sometimes not possible. 

Biomonitoring results from Vieques can be compared with national data, such as the Fourth National 

Report on Human Exposure to Environmental Chemicals (CDC 2009). But more appropriate comparisons

should include comparison with biomonitoring data from residents of the main island of Puerto Rico. 

These limitations are described in more detail later in this chapter. 

3.2. Assessment of Available Vieques Human Biomonitoring Studies Data 

Because ATSDR’s previous public health assessments did not review biomonitoring data from Vieques, 

this chapter and its appendices describe the biomonitoring data in detail. Because of confidentiality 

issues, ATSDR does not have access to individual results. Thus our evaluation relies on information 

reported by the investigators. The important fact is, however, that biomonitoring data available for 

Viequenses cannot be used to determine whether residents of Vieques were exposed to past, military 

exercise-related constituents. 

Since 1999, either the Puerto Rico Department of Health or Puerto Rican scientists and doctors have 

conducted several human biomonitoring studies in Vieques. These studies have focused on measuring 

metals in hair, urine, blood, or stool samples. They are listed in Table 3-1 (Colón de Jorge undated; Ortiz 

Roque 2004; Ortiz Roque 2002; PRDOH 2006; Rodríguez Sierra 2009). Highlights are provided here. The

studies are described in more detail in Appendix 3-A. 

Dr. Carmen Colón de Jorge conducted one of the first studies. She analyzed hair samples from 30 

residents with preexisting health conditions and analyzed seven stool samples for metals. At about the 

same time, Dr. Carmen Ortiz Roque’s study analyzed hair samples from about 200 Viequenses for 

various metals. The doctors concluded their data showed Viequenses had heavy metal exposure and 

that the exposure had resulted in harmful health effects (Colón de Jorge; Ortiz Roque 2002, 2004).

Dr. Colón de Jorge reported numerous metals in hair. That report stated that based on the ranges 

provided by the service laboratory that made the measurements (i.e., Doctor’s Data, Chicago, Illinois) a 

sizeable percentage of the 30 tested residents exceeded the reference range established by Doctor’s 

Data. Dr. Colón de Jorge noted that in about 70% of the 30 tested residents, arsenic and antimony in 

hair were above the reference ranges selected by the reporting laboratory. Dr. Colón de Jorge’s report 

stated that because antimony levels in bombs are high, the antimony exceedences proved residents 

were exposed to metals from munitions. But the report did not explain how residents could have been 

exposed to antimony or to other metals.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 60

Table 3-1. Vieques human biomonitoring studies

Source Title

Puerto Rico Department 

of Health

Executive summary of the prevalence study of heavy

metals in Vieques, 2006, draft unpublished manuscript

Dr. Carmen Ortiz Roque Mercury contamination in reproductive age women in a Caribbean 

island: Vieques. J. Epidemiol Community Health 58:756-757, 2004

Dr. Carmen Ortiz Roque Heavy metal exposure and disease in the proximity of a military base. 

Unpublished manuscript, 29 January 2002

Dr. Carmen Colón de 

Jorge

Innocence battered on Vieques, scientific investigation of toxic metals 

present in the biological terrain of Vieques children and adults and 

their effects on nutrient minerals utilizing hair and feces analysis 

(preliminary report). Unpublished manuscript, no date

Dr. Carlos Rodríguez

Sierra

Webcast, October 30, 2009, New look at the opening of the case of 

Vieques, www.telecoque.net

Most commercial laboratories that report results will develop their own reference range for what they 

consider normal or typical concentrations of a chemical in a biological matrix. But such ranges can vary 

with the populations tested. Inevitably, exposures will vary from population to population based on 

factors such as age, sex, race/ethnicity, and underlying health conditions. Laboratories will sometimes 

develop a concentration that they consider above the expected range or that they sometimes even 

consider toxic. Often for these ranges (and, if reported, for the toxic levels) the basis is the company’s 

own cumulative experience from many years of laboratory testing. Such reference ranges or identified 

toxic levels are not regulated by the government nor are they approved by a medical or scientific 

organization.

Dr. Ortiz Roque’s study identified several residents with hair-mercury levels above 12 ppm—the level 

the National Research Council identified as causing a 5% increase in abnormal results on a 

neurocognitive test (i.e., the Boston Naming test) for children who were exposed in utero (NRC 2000). 

Dr. Ortiz Roque showed that higher mercury levels were associated with Viequenses’ higher fish 

consumption (Ortiz Roque 2002, 2004). But the patients in this investigation were not randomly 

selected. Thus insofar as the prevalence of Viequenses’ elevated mercury levels is concerned, any firm 

conclusions are difficult to draw. That said, Dr. Ortiz Roque’s identification of three residents with hair 

mercury levels above 12 ppm is an important finding. A major limitation of hair analysis in a free-living 

population is the difficulty in discerning whether the metal was internally deposited from the blood 

stream or externally deposited from the air or the use of products on the hair. While hair measurements 

for mercury have been used in previous population studies, efforts to understand or control external 

deposition are usually investigated.

From 2006 to 2008, Dr. Carlos Rodríguez Sierra collected hair, nail, and urine samples from 52 Viequense 

adults. He divided the study subjects into high and low fish-consumption groups. This division is 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 61

necessary because persons who eat fish regularly will have high levels of urinary arsenic. This arsenic is 

predominantly arsenobetaine—a nontoxic arsenic form. An October 30, 2009 Webcast sponsored by 

Casa Pueblo de Adjuntas carried a report that high levels of arsenic in hair, nails, and urine were not 

detected at the time of sampling. Hair and nail sample levels were below 1-μg/g (microgram per gram), 

which Dr. Rodríguez Sierra used as a reference value (Rodríguez Sierra C. 2009). The Webcast further 

reported that the sum of inorganic arsenic species and their metabolites in urine was less than 50 μg/g 

creatinine, which Dr. Rodríguez Sierra also used as a reference value. This value likely comes from 

occupational exposure studies; they might have used the value to assess excessive exposure to arsenic 

(ACGIH 2000; WHO 2001). The American Conference of Governmental Industrial Hygiene (ACGIH) 

currently recommends 35 μg/g creatinine as an action level of the sum of inorganic arsenic species and 

their metabolites for occupational testing (ATSDR 2007). 

Dr. Rodríguez Sierra reported that the median and 95th percentile of total inorganic arsenic (As V, As III, 

DMA, MMA) levels in Viequenses’ urine were slightly above the respective levels reported in the 2003–

2004 Fourth National Report on Human Exposure to Environmental Chemicals.

16 Dietary sources of 

inorganic arsenic include chicken as well as rice, particularly when rice is grown in arsenic-contaminated 

soils (Lasky et al. 2004; Potera 2007; Williams et al. 2007). Whether these slightly higher levels of 

inorganic arsenic in urine are associated with harmful effects, however, is impossible to determine. 

As a follow up to these studies, PRDOH conducted a comprehensive biomonitoring study in which it 

collected hair, urine, or blood samples from 500 randomly selected Viequenses. The results were shared 

with some of those who participated, but no public report was ever released (PRDOH 2006). In August 

2009, ATSDR obtained a draft of the unpublished manuscript. ATSDR found that inappropriate units 

were used for some of the results, thus rendering some measurements uncertain.

Nevertheless, the PRDOH manuscript reported that in 20% of the participants, either aluminum, lead, or

mercury in blood; uranium, cadmium, or nickel in urine; or nickel or arsenic in hair exceeded Quest 

Laboratories’ reference range.

17 For some—but not all—of the elevated levels, the PRDOH manuscript

identified as possible sources cigarettes, hair dyes, and seafood consumption. For other residents, the 

origin of high metal levels in urine, hair, and blood could not be identified. As mentioned previously, the 

elevated levels of metals (except mercury) in hair are difficult to interpret. Hair analysis leaves 

unanswered whether the metals were ingested and were bound to the hair from direct contact. Note 

also that the PRDOH manuscript stated that they did not test children 4 years and younger.

 

16 The basis for CDC’s Fourth National Report on Human Exposure to Environmental Chemicals is an ongoing 

national survey that samples the U.S. population every 2 years. Each 2-year sample consists of about 2,400 

persons. The Fourth Report includes findings from national samples for 1999–2000, 2001–2002, and 2003–2004. 

The data are analyzed separately by age, sex, and race/ethnicity groups. The Fourth Report is available at 

www.cdc.gov/exposurereport/.

17 While the draft PRDOH manuscript states that Quest Laboratories in San Juan, PR conducted the clinical 

analyses, the correct name is most likely Quest Diagnostics.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 62

All that said, however, Dr. Colón de Jorge’s and Dr. Ortiz Roque’s biomonitoring studies did support the 

conclusions in the PRDOH manuscript.

3.3. Strengths and Limitations of Human Biomonitoring for Vieques

The use of biomonitoring results to assess public health issues requires consideration of biomonitoring’s

previously enumerated strengths and limitations. Biomonitoring data will allow an investigator to look at 

markers of exposure and markers of effect. When toxicological information is available, markers of 

effect allow an investigator to determine whether harmful consequences might result from the 

measured level of a chemical or its metabolite. Extensive toxicologic data support current research on 

lead in blood, cadmium in urine, and mercury in hair. Once the concentration is known, health scientists 

can draw conclusions about the presence or absence of risk. For other metals in blood or urine, 

toxicological data and research are limited, thus reducing the ability to draw firm conclusions. For 

example, no human toxicity data are available for urine levels of antimony, beryllium, cesium, 

molybdenum, platinum, and tungsten. Thus while biomonitoring might identify populations with 

excessive exposure, assessing the risk of that exposure’s harmful effects might not be possible (CDC 

2009).

But a particular biomonitoring strength is the availability of comparison data for a representative sample 

of the U.S. population. Those comparison data are in the National Reports on Human Exposure to 

Environmental Chemicals at http://www.cdc.gov/exposurereport/ (CDC 2009). National data are also 

available on mercury in hair (McDowell 2004). 

An important consideration when using National Health and Nutrition Examination Survey (NHANES)

biomonitoring data is that differences in levels between populations (e.g., regional, cultural, and ethnic) 

are likely due to differences in exposures, pharmacokinetics, and other factors. Thus U.S. population 

data can only be cautiously applied to the Commonwealth of Puerto Rico. If any future biomonitoring 

investigations are undertaken for the Vieques population, a comparison population from the 

Commonwealth of Puerto Rico or another nearby island-based population may be more appropriate.

To understand possible exposure sources, subjects with an elevated metal or chemical concentration

should be subsequently investigated for attributable sources of exposure.

3.4. The Special Case of Hair Analysis for Metals and Other Elements

3.4.1. ATSDR’s 2001 Hair Panel

During ATSDR’s November 2009 meeting with invited scientists, we were asked to reconsider the 

agency’s position on testing metals in hair. In 2001, ATSDR sponsored a workshop and invited 

researchers in the medical, environmental, and toxicological fields to advise the agency of the utility of 

measuring metals and organic chemicals in hair. The workshop panelists agreed on the following 

summary statement related to the overall usefulness of hair analysis in evaluating environmental 

exposures:
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 63

For most substances, insufficient data currently exist that would allow the 

prediction of a health effect from the concentration of the substance in hair. 

The presence of a substance in hair may indicate exposure (both internal and 

external), but does not necessarily indicate the source of exposure (ATSDR 

2001).

The panelists agreed that a relationship between contaminant concentrations in hair and any kind of 

measurable outcome—provided external contamination could be ruled out—have only been established 

for methylmercury and, to a limited extent, for arsenic (e.g., segmental analysis for forensic analysis). 

Unique forensic settings might be available for other substances (ATSDR 2001).

The panelists identified several factors that limit interpretation of even the most accurate, reliable, and 

reproducible laboratory results. These include

 A lack of reference (or background) ranges in which to frame the interpretation of results. 

 Difficulties in distinguishing endogenous (internal) from exogenous (external) contamination in 

hair. 

 Some panelists thought the then-current literature suggested the absence of any reliable 

washing method capable of separating external contamination from internal element 

deposition. One potential remedy was that where possible, identifying metabolites—or other 

unique markers of internal exposure—for substances of interest would be most helpful in 

distinguishing internal and external contamination.

 A lack of understanding of how and to what extent environmental contaminants are 

incorporated into the hair.

 A lack of correlation between levels in hair and blood and other target tissues, as well as the lack 

of epidemiologic data linking substance-specific hair levels with adverse health effects. 

 Little pertinent information is available for the study of environmentally relevant organic 

compounds in hair. The panel recommended taking advantage of what is known about hair 

analysis for testing for drugs of abuse (ATSDR 2001).

3.4.2. Current Status of Hair Analysis Validity

ATSDR staff checked with several sources to determine the current validity of hair analysis. The 

American Medical Association (AMA) supports the conclusions of those panelists who participated in 

ATSDR’s 2001 workshop. The German Federal Environment Agency (GFEA 2005) has a similar 

recommendation. One exception is carefully tested hair specimens for mercury. The NHANES survey 

includes mercury in hair from a national population for one 2-year period (1999–2000). Therefore, 

comparison of hair mercury levels with a national group is possible. This might help in identifying those 

with excessive mercury exposure. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 64

3.5. Conclusions and Recommendations

3.5.1. Conclusions

1. Since 1999, Vieques has hosted at least five human biomonitoring investigations. Puerto Rican 

scientists, physicians, or the Puerto Rico Department of Health (PRDOH) conducted all of them. 

The PRDOH has conducted the most extensive sampling effort, collecting biological specimens 

from 500 randomly selected Viequenses. The PRDOH manuscript reported that in 20% of the 

participants, either

• Aluminum, lead, or mercury in blood; 

• Uranium, cadmium, or nickel in urine; or 

• Nickel or arsenic in hair 

exceeded the laboratory’s reference range. The PRDOH manuscript identified cigarette use and 

hair dyes, as well as the consumption of seafood, as possible sources for some but not all the 

elevated levels. The PRDOH manuscript acknowledged that for some residents, it could not 

identify the source of high metal levels in urine, hair, and blood. The PRDOH manuscript did not 

report mercury levels in hair. Results from Dr. Ortiz Roque’s investigations showed that some 

residents had elevated levels of mercury in hair, and that the most likely source was fish 

consumption; other possible sources, however, were not completely ruled out.

2. Data from these studies showed that in blood, urine, hair, or feces, some residents of Vieques 

had elevated levels of various metals. While some of these elevated levels might be explained 

by cigarette use, seafood consumption, or hair dyes, they did not account for all the elevated 

levels. In particular, biomonitoring results from Dr. Ortiz Roque showed that some Viequenses 

had elevated mercury in hair above 12 ppm, the level identified by the NAS to cause harm in 5% 

of fetuses exposed in utero. Dr. Ortiz Roque also showed that mercury in hair was associated 

with fish consumption. In contrast, the PRDOH study did not find excessive mercury levels in 

blood, although the study either did not measure for or did not report mercury level in hair. 

Thus some uncertainty exists about the prevalence of high mercury levels in Viequenses. Except 

for mercury, metal content in hair is difficult to interpret. Metals can bind directly to hair from 

the use of commercial hair products, making difficult any distinction between internal metal 

exposure via ingestion and inhalation versus external exposure resulting from contact with the 

metal in the environment (e.g., shampoo, dyes, dirt). 

3. These studies were unable to investigate each person’s environment to identify the source for 

those who had excessive metals in hair, urine, or blood. The PRDOH study came closest to 

identifying possible sources (e.g., cigarette and hair dye use, seafood consumption) but 

acknowledged an inability to identify the source or sources for all residents with excessive 

metals exposure. Either through the survey instrument or through an in-home visit, it may be 

possible to identify other sources that increase metal exposure, such as cooking utensils, metal 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 65

residues in foods (e.g., tea and vegetables), consumption of drinks with metallic packaging, 

antacid formulations and antiperspirant formulations.

4. ATSDR remains cautious in making decisions about using hair as an indicator of exposure to 

environmental contaminants and as an indicator of risk of harmful effects. A major problem in 

interpreting metal concentrations in hair is whether the metal content resulted from internal 

exposure (e.g., from ingestion or inhalation) or from external exposure (e.g., the hair coming in 

contact with a metal-containing product). Currently, no washing method is capable of removing 

exogenous metal contaminants while leaving endogenous metals undisturbed. Chemicals such 

as methylmercury, which originate generally from dietary sources, suffer less from this 

drawback, provided unusual sources of inorganic mercury do not complicate the picture, (e.g., 

mercury vapor in occupational or home settings).

5. These biomonitoring results do not permit any conclusions about exposure to the bombingrelated contaminants. 

3.5.2. Recommendations

1. Viequenses may be exposed to mercury in fish and cadmium in pigeon peas. These exposures

may warrant additional environmental investigations, such as sampling locally grown produce 

for cadmium and gathering more information about fish consumption and possibly mercury in 

fish. The information could be used to decide whether to undertake human testing for mercury

and cadmium in blood or urine. If other environmental exposures are identified, additional 

human biomonitoring investigations may be considered. More detailed information about 

ATSDR’s recommendations concerning fish and locally grown produce can be found in Chapter 

2, Section 2.3.2 and Chapter 5, Section 5.3.2, respectively.

2. Although ATSDR is not recommending a comprehensive, systematic biomonitoring effort at this 

time, public health officials could consider a limited and focused human biomonitoring 

investigation following the release of this report. If a biomonitoring investigation is conducted, it 

should include a comparison group from mainland Puerto Rico. If requested, CDC/ATSDR subject 

matter experts will provide technical assistance and support to PRDOH in planning and 

conducting such an investigation.

3. Viequenses who remain concerned about exposure to mercury, cadmium, other metals, or 

metalloids should consult their healthcare providers to discuss the need for and cost of testing. 

A qualified laboratory should do the testing and analysis.

4. CDC/ATSDR can provide a list of qualified laboratories that can perform the tests. And if 

requested, CDC/ATSDR can provide information to healthcare providers about tests for metals 

in biologic samples. 

3.6. References 

Apostolic P, Schaller KH. 2001. Urinary beryllium--a suitable tool for assessing occupational and 

environmental beryllium exposure. Into Arch Occupy Environ Health 74:162–66.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 66

[ACGIH] 2000. Threshold limit values for chemical substances and physical agents and biological 

exposure indices. American Conference of Governmental Industrial Hygienists, Cincinnati, OH.

[AMA] American Medical Association. 2009. Health and ethics policies of the AMA House of Delegates. 

Available at: http://www.ama-assn.org/ad-com/polfind/Hlth-Ethics.pdf [accessed 2009 Dec 10]. 

[AMA] American Medical Association. 2004. Diagnosis and management of food borne illnesses a primer 

for physicians and other health care professionals. Food borne Illnesses Table: Non-infectious Agents. 

Available at: http://www.ama-assn.org/ama1/pub/upload/mm/36/2004_food_table_non.pdf [accessed 

2010 Jan 29).

[ATSDR] Agency for Toxic Substances and Disease Registry. 1999 March. Toxicological profile for mercury 

(update). Atlanta: US Department of Health and Human Services, Public Health Service.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2001. Summary report, hair analysis panel 

discussion: exploring the state of the science. Atlanta: US Department of Health and Human Services, 

Public Health Service; 12-13 Jun.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2007. Toxicological Profile for Arsenic 

[Update]. Atlanta: US Department of Health and Human Services, Public Health Service; August.

Caldwell KL, Jones RL, Verdon CP, Jarrett JM, Caudill SP, Osterloh JD. 2009. Levels of urinary total and 

speciated arsenic in the US population: National Health and Nutrition Examination Survey 2003-2004. J 

Exp Sci Environ Epi 19:59-68.

[CDC] Centers for Disease Control and Prevention. 2001. Blood and hair mercury levels in young children 

and women of childbearing age—United States, 1999. MMWR 50(8):140-3; 2March.

[CDC] Centers for Disease Control and Prevention. 2009. Fourth National Report on Human Exposure to 

Environmental Chemicals. Available at: http://www.cdc.gov/exposurereport [accessed December 10, 

2009].

[CDC] Centers for Disease Control and Prevention. 2009. The Third National Report on Human Exposure 

to Environmental Chemicals. National Center for Environmental Health, Atlanta, GA. NCEH Pub. No. 05-

0570. Available at: http://www.cdc.gov/exposurereport [accessed 2009 Nov 12].

[CDC] Centers for Disease Control and Prevention. 1997. Screening Young Children for Lead Poisoning:

Guidance for State and Local Public Health Officials, Atlanta, GA.

[CDC] Centers for Disease Control and Prevention. 2002. Managing Elevated Blood Lead Levels Among 

Young Children: Recommendations from the Advisory Committee on Childhood Lead Poisoning 

Prevention, Atlanta, GA

Colón de Jorge C, Santiago E, Brooks JF, Pérez FL, Rivera J, Valle R. (Undated). Innocence battered on 

Vieques: scientific investigation of toxic metals present in the biological terrain of Vieques children and 

adults and their effects on nutrient minerals utilizing hair and feces analysis (preliminary report). 

(Unpublished manuscript.)
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 67

[GFEA] German Federal Environment Agency (Umweltbundesamt). 2005. Hair analysis in environmental 

medicine. Gesundheitsschutz 48(2);246–50. Available at: http://www.umweltdaten.de/gesundheite/monitor/hair_analysis.pdf [accessed 2010 Jan 29].

Hwang Y-H, Lee Z-Y, Wang J-D, et al. 2002. Monitoring of arsenic exposure with speciated urinary 

inorganic arsenic metabolites for ion implanter maintenance engineers. Environmental Research 90;207-

216.

Lasky T, Sun W, Kadry A, Hoffman M. 2004. Mean total arsenic concentrations in chicken 1989-2000 and 

estimated exposures for consumers of chicken. Envir Health Perspect 112(1):18-21.

Mahaffey KR, Clickner RP, Jeffries RA. 2009. Adult women’s blood mercury concentrations vary 

regionally in the United States: association with patterns of fish consumption (NHANES 1999–2004). 

Environ Health Perspect 117(1):47–53.

McDowell MA, Dillon CF, Osterloh J, Bolger M, Pellizzari E, et al. 2004. Hair mercury levels in U.S. 

children and women of childbearing age: reference range data from NHANES 1999–2000. Environ Health 

Perspect 112(11):1165-71.

[NRC] National Research Council. 2000. Toxicological Effects of Methymercury. Washington (DC): 

National Academy of Sciences, National Research Council. Pubs: National Academy Press. 

Ortiz Roque C, López-Rivera Y. 2004. Mercury contamination in reproductive age women in a Caribbean 

island: Vieques. J. Epidemiol Comm Health 58:756–57.

Ortiz Roque C. 2002. Heavy metal exposure and disease in the proximity of a military base. (Unpublished 

manuscript) 2002 Jan 29.

Potera C. 2007. U.S. rice serves up arsenic. Envir Health Perspect 115(6):A296.

[PRDOH] Commonwealth of Puerto Rico, Department of Health. 2006. Executive summary of the 

prevalence study of heavy metals in Vieques. San Juan: PR DOH; November.

Rodriquez Sierra C. 2009. New look at the opening of the case of Vieques. Webcast sponsored by Casa 

Pueblo de Adjuntas (www.casapueblo.org) on October 30, 2009 from this url: www.telecoqui.net. 

Seidel S, Kreutzer R, Smith D, McNeel S, Gilliss D. 2001. Assessment of commercial laboratories 

performing hair mineral analysis. JAMA 285(1):67–72.

Williams PN, Raab A, Feldman J, Meharg AA. 2007. Market basket survey shows elevated levels of As in 

South Central U.S. processed rice compared to California: Consequences for human dietary exposure. 

Envir Sci & Tech 41(7):2178-2183.

[WHO] World Health Organization. 2001. Arsenic and arsenic compounds. Environmental Health Criteria 

224, Geneva.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 68

3.7. Appendix 3-A. Biomonitoring

3.7.1. Vieques, Puerto Rico-Related Human Biomonitoring Study Summaries

Several biomonitoring investigations have been conducted on Vieques, with the first samples collected 

in 1999 (see Table 3A-1). These investigations are summarized in Table 3A-1 and described in detail in 

the text of this appendix (Colón de Jorge; Ortiz Roque 2004; Ortiz Roque 2002; PRDOH 2006; Rodriquez

Sierra 2009).

Table 3A-1. Vieques human biomonitoring studies

Source Title

Puerto Rico Department 

of Health

Executive summary of the prevalence study of heavy

metals in Vieques, 2006, draft unpublished manuscript

Dr. Carmen Ortiz Roque Mercury contamination in reproductive age women in a Caribbean 

island: Vieques. 2004. J. Epidemiol Comm Health 58:756–57

Dr. Carmen Ortiz Roque Heavy metal exposure and disease in the proximity of a military base. 

Unpublished manuscript, 29 January 2002

Dr. Carmen Colón de 

Jorge

Innocence battered on Vieques, scientific investigation of toxic metals 

present in the biological terrain of Vieques children and adults and 

their effects on nutrient minerals utilizing hair and feces analysis 

(preliminary report). Unpublished manuscript, undated

Dr. Carlos Rodriquez

Sierra

Webcast, October 30, 2009, New look at the opening of the case of 

Vieques, www.telecoque.net

3.7.2. PRDOH Biomonitoring Study

The most extensive human biomonitoring study conducted to date is a two-phase study of 500 Vieques 

residents conducted by the Puerto Rico Department of Health starting in May 2004. This study was 

conducted after ATSDR’s public health assessments were published and so represent new data to 

consider. For this reason, the study is described in detail.

In the first phase, the PRDOH manuscript reported interviewing 500 Vieques residents, collecting

biological samples, and analyzing for the following:

 Arsenic, cadmium, and nickel in hair and urine,

 Aluminum, lead, and mercury in blood, and

 Uranium in urine.

As stated in the PRDOH manuscript, the second phase involved collecting and analyzing blood samples 

from Phase 1 participants with metal concentrations deemed toxic according to the reference values 

provided by the analytical laboratory. Phase II was from December 2005 to March 2006. In PRDOH 

manuscript stated that the information obtained from this study would be used to determine the 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page 69

magnitude and scope of the problem, generate hypotheses and identify areas that warrant intervention 

from a public health perspective. The PRDOH report includes recommendations for follow-up activities.

3.7.2.1. PRDOH Study, Phase 1

Five hundred persons were randomly chosen from residents 5 years of age or older who lived in Vieques 

before 2000. The interview collected information about age, sex, residence history, smoking status, 

employment, water consumption and use, food preparation and consumption, medicines, hobbies, and 

chemicals/solvent use. In particular, information was collected about fish and shellfish consumption 3 

days before the sample collection. 

To reduce external contamination from the environment, hair samples were collected from the pubic 

region or, if that was not possible, a 1-inch hair sample from the scalp was collected near the root. Table 

3A-2 provides a summary of metal concentrations in blood, urine, and hair from Phase 1. Note that 

comparing pubic hair results with scalp hair may not be appropriate.

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 71

Table 3A-2. PRDOH Phase 1 results of heavy metal analysis of Vieques residents. 

Note: The geometric means for some metals (e.g., uranium) in the study population appear to be the 

average of detectable concentrations. For other metals (e.g., mercury), nondetectable levels were 

replaced by zero while for other metals (e.g., aluminum), nondetectable levels were replaced by 1 μg/L. 

For cadmium, the report states that nondetect levels were replaced by a value but did not specify the 

value. The treatment of nondetects is very important when calculating means and comparing those 

means to either a reference or toxicity value or to a national average. Complicating the comparisons

even further is that for some metals, the detection limit was high. When nondetectable levels are part of 

the database, the calculation of a geometric mean could be biased high or low depending upon what 

value was substituted for the nondetect. Therefore, caution is warranted when comparing these study 

population means to means from reference populations, who are likely to have handled nondetectable 

concentrations differently or had lower detection limits. For example, the NHANES means replace 

nondetectable concentrations with the detection limit divided by the square root of two. For some 

metals, the limitations of the detection limit are acknowledged in the PRDOH report.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 72

% Detection

Geometric 

Mean of 

PRDOH 

Sample

(n=500)1

Geometric 

Mean 

General 

Population 

Selected by 

PRDOH

Geometric 

Mean

2003-2004

NHANES2

Level of 

Possible 

Toxicity

(as reported 

by service

laboratory)

Comments

Aluminum 

in blood

μg/L

93 17.6

(unreliable, 

see 

comment)

1-4

3 NA ≥ 605 Quest Laboratories reports 

a high detection limit (10 

ug/L), which adds 

uncertainty to the reported 

geometric mean of 17.6

because 1 μg/L was used 

for non-detect values. 

Nevertheless, some 

persons appear to have 

elevated Al in blood; 109 

persons ≥ 40 μg/L ; 10 

persons ≥ 60 μg/L

Lead in 

blood

μg/dL

99 3.53 1.6641.43 20 

μg/dL5

Six persons ≥ 10 μg/dL; 2 

persons ≥ 20 μg/dL

Median age = 56 years; All 

males; 3 work with 

petroleum products

No safe level identified;

CDC case management 

level for children,

10 ug/dL

Mercury 

in blood

μg/L

99 5.02 

(unreliable, 

see 

comment)

1.0260.797 46-797

The PRDOH report states 

that the detection limit (5 

ug/L) was too high to 

estimate a reliable 

population mean; 

Maximum level detected 

was 13 μg/L. While the 

draft report states that zero 

was used for non-detects, it 

is uncertain if this is 

actually the case for the 

average of 5.02 ug/L as 

reported in the PRDOH

manuscript. 

Total 

arsenic in 

urine μg/L

95 33.6 38.248.3 > 50 

μg/L5

23% > 50 μg/L (117 of 500)

39 of 257 persons who did 

not eat fish had urine 

arsenic > 50 μg/L. Another 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 73

% Detection

Geometric 

Mean of 

PRDOH 

Sample

(n=500)1

Geometric 

Mean 

General 

Population 

Selected by 

PRDOH

Geometric 

Mean

2003-2004

NHANES2

Level of 

Possible 

Toxicity

(as reported 

by service

laboratory)

Comments

possible source of urinary 

arsenic is rice.

Arsenic in 

hair ppm

65 0.15 0.154 NA -- One person > 3 ppm 

Uranium 

in urine 

μg/L

1 0.14 (6 

individuals)

0.007

4

0.008 -- Six women with detectable 

levels. Mean of these 6 

women is 0.14 μg/L. 

Nondetectable 

concentrations were not 

included in calculating the 

mean.

Cadmium 

in hair 

ppm

82 0.14 <0.154 NA >3.45 No participant exceeded 

3.4 μg/L

Cadmium 

in urine 

μg/g 

87 0.43 0.3076,8 0.211 >25Eleven persons >1.03 ug/g

Two persons >lab’s toxicity 

levels of 2 μg/g—for some 

persons, probably smokingrelated 

Nickel in 

urine

79 2.05 < 24 NA >1005

Three persons exceeded 

the lab’s threshold 

reference range.

No participant exceeded 

the lab’s toxicity levels of 

100 μg/g creatinine

Nickel in 

hair

97 0.64 0.394 NA --

1 Nondetectable samples were handled in different ways for various averages. For aluminum, 35 missing values 

were replaced by 1, which is the minimum concentration expected in a population. For cadmium in urine, 64 

values were replaced by a value, although the actual value was not stated in the report. For uranium, the average 

consists of just the six samples with detectable concentrations. A low percent detection indicates that many 

people had nondetectable levels, thus the mean of the detectable levels is uncertain

2 NHANES National Survey, 2003-2004. This 2-year period was chosen because Phase I of the PRDOH study was 

conducted in May 2004.

3 PRDOH 2006 report. Levels reported by Poison Line of Puerto Rico

4 PRDOH 2006 report, source not identified

5 Source = Quest Laboratories

6 Source = 1999-2002 NHANES
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 74

7 bmdl05, Source = U.S.EPA (IRIS, Methylmercury)

8 The value 0.307 ug/L could not be confirmed from NHANES

NA = not available

Aluminum: The geometric mean blood aluminum was 17.6 μg/L (95% CI 17.02–18.34); Quest 

Laboratories reported, however, the detection limit for aluminum in blood was 10 μg/L. Because the 

PRDOH manuscript reported using 1 μg/L for 35 nondetectable levels, some uncertainty exists in the 

geometric mean of 17.6 μg/L. The PRDOH manuscript reported using a geometric mean for aluminum in 

blood in the United States of 1 to 4 μg/L, which was provided by the Poison Line of Puerto Rico. Twentytwo percent (109 persons) showed levels of 40 μg/L or greater—the laboratory’s upper threshold level 

of the reference range for a population. Two percent (10 persons) had levels greater than 60 μg/L, the 

laboratory’s toxicity threshold. Persons between the ages of 20 and 44 were five times more likely to 

have aluminum levels above 40 μg/L than those 65 and older (PRR=4.99, p<0.05). Medicines and 

occupation were not identified as possible sources.

Lead: The geometric mean blood lead level for all ages in the study population was 3.53 μg/dL compared 

with the geometric mean of 1.66 μg/dL from the 1999-2000 NHANES survey (as reported in the PRDOH

manuscript) and 1.42 μg/dL from the 2003-2004 NHANES survey. In addition, 16% (81/500) of 

participants (all ages) had blood lead levels greater than 5 μg/dL compared with 5% from NHANES. Older 

participants (46–64 years and 65+) were more likely to have levels greater than 5 μg/dL than were the 

youngest age group tested (5 to 19 years). Participants who worked with metals and with petroleumderived products, and those lacking a water purification system were more likely to have elevated blood 

lead levels. For example, the following occupations or hobbies showed a high prevalence risk ratio for 

elevated blood lead levels: car/truck maintenance, electrical repair, metal work, solvent use, petroleum 

product use, or metal use. Smokers and participants who consumed seafood within 3 days of the test 

showed a higher probability of elevated blood lead levels. The PRDOH manuscript stated, however, that 

smoking did not account for all participants with elevated blood lead levels. This conclusion is supported 

by the observation that the geometric mean of blood lead levels for nonsmokers was twice the national 

average. ATSDR agrees with this conclusion.

Mercury: A comparison of average blood mercury levels in Vieques residents to other populations is not 

reliable—the detection limit for mercury in blood was too high (i.e., 5 μg/L). The NHANES survey finds 

the average blood mercury level for the U.S. population is 1 μg/L. But coastal populations have higher 

fish intake and a higher frequency of women with elevated blood mercury levels compared with the 

national average and inland areas. For example, 8% of women in coastal areas have blood mercury 

levels greater than 5.8 μg/L compared with 2% of women from inland areas (Mahaffey 2009). 

Interestingly, Mahaffey reported blood mercury levels by race/ethnicity as well: almost 16% of women 

whose ancestry is Asian, Native American, Pacific Islands, and the Caribbean Islands have blood mercury

greater than 5.8 μg/L. The highest blood level detected in the PRDOH study was 13 μg/L.

To provide perspective, U.S.EPA estimated a benchmark-dose, lower confidence limit of a 5% (BMDL05) 

adverse response rate in fetal development. U.S.EPA identified the BMDL05 cord blood mercury level in 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 75

women to be between 46–79 μg/L (USEPA 2009). U.S.EPA derived this range of blood mercury levels 

using human data from the Faroe Islands fish-eating study and the agency’s benchmark dose methods 

(USEPA 2009). U.S.EPA’s values are similar to those derived by the National Academy of Sciences’ (NAS) 

Committee on the Toxicological Effects of Methymercury. Using a similar benchmark dose approach, the 

NAS identified the 5% adverse effect level (i.e., a benchmark dose, BMD) at 85 μg/L as a cord blood 

mercury level and estimated a 5% lower confidence limit of 58 μg/L (BMDL05). NAS stated that 

corresponding values in hair result in a benchmark dose of 17 ppm and BMDL05 of 12 ppm (NRC 2000). 

Arsenic: The PRDOH manuscript stated that the geometric mean for arsenic in urine was below what 

was expected (see Table 3A-2, 33.6 vs. 38.2 μg/L). The report did not state the source of the reference 

levels. The geometric mean of the study population is higher than the geometric mean from the 2003-

2004 NHANES survey (33.6 vs. 8.3 μg/L. Total urine arsenic levels were above 50 μg/L in 25% of the 

participants (i.e., 117/473). The median age of participants with levels greater than 50 μg/L was 50 years 

(range = 5 to 90 years). The PRDOH manuscript stated that risk factors associated with elevated urine 

arsenic were the age groups 45–64 and over 65, smokers, seafood eaters, seafood consumption within 3 

days of the test, regular contact with animals, and those who worked with metals.

Still, the urine arsenic test did not distinguish between inorganic arsenic and organic arsenic. When 

people eat fish a few days before providing a urine sample, nonharmful organic arsenic arsenobetaine is 

often found in urine at high levels. Freshwater and saltwater fish contain the organic arsenicals,

arsenobetaine, and to a much lesser extent, arsenocholine. 

Whenever total arsenic levels exceed 50 μg/L and people eat fish, the high levels of total arsenic are 

probably the result of measuring arsenobetaine and arsenocholine and thus do not indicate toxicity

(Caldwell et al. 2009). Arsenobetaine and arsenocholine are excreted very quickly through the kidneys 

without being metabolized and are relatively nontoxic to humans. Some shellfish contain small amounts 

of inorganic arsenic in addition to organic arsenic; consequently, the arsenic levels reported in the 

PRDOH study are likely to be mostly organic arsenic with some inorganic arsenic

The PRDOH report stated that 267 participants did not eat seafood and that 39 of these participants had 

urine total arsenic levels above 50 μg/L. This result points to another source of arsenic, or it points to 

dietary recall problems. Other dietary sources of arsenic in the human diet include chicken as well as

rice, particularly when rice is grown in arsenic-contaminated soils (Lasky et al. 2004; Potera 2007; 

Williams et al. 2007).

Uranium: Six of the 500 participants had detectable levels of uranium in urine. The geometric mean 

uranium level in urine in these six participants was 0.14 μg/L, which is greater than the 2003-2004 

NHANES geometric mean of 0.008 μg/L and the 95th percentile of 0.031 μg/L. All six participants are 

women, and five were not employed when interviewed. The median age was 57. No uranium levels 

exceeded Quest Laboratories’ threshold level or toxic level. The source of uranium is unknown.

Cadmium: The geometric-mean hair-cadmium level in the study population (n=429) was 0.14 ppm. The 

PRDOH report states that this value is similar to its reference value of less than 0.15 ppm. But the report 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 76

does not identify the source of the reference value of less than 0.15 ppm. In any event, no participant 

exceeded Quest Laboratories’ hair toxicity threshold of 3.4 ppm. 

The PRDOH report stated that the geometric mean cadmium level in urine in the study population was 

higher than the 1999-2000 NHANES geometric mean (0.43 vs. 0.31 μg/g). Because of interference from

molybdenum oxide, CDC has since corrected the 1999-2000 NHANES value. The corrected geometric 

mean from the 1999-2000 NHANES is 0.181 μg/g. The geometric mean from the 2003-2004 NHANES is 

0.21 μg/g. Eleven participants had cadmium urine levels above 1.03 ug/g, the 95th percentile from the 

1999-2000 NHANES (uncorrected for molybdenum oxide). Two participants showed urine cadmium 

levels above the laboratory’s toxic level of 2 μg/g creatinine. OSHA’s worker action level is 3 μg/g 

creatinine. The median age for participants with urine cadmium levels above 1.03 μg/g creatinine was 

55. Smokers showed urine cadmium levels five times higher than did nonsmokers.

Nickel: Participants’ geometric mean nickel levels in urine (2.05 μg/g creatinine) was similar to the 

reference value (less than 2 μg/g creatinine). The report does not identify the source of the reference 

value. Three participants (2 women and 1 man) had urine nickel levels that exceeded Quest 

Laboratories’ threshold of 6.2 μg/g creatinine in women and 10.2 μg/g creatinine in men. No urine nickel 

levels exceeded the Quest Laboratories’ 100 μg/g- creatinine toxicity threshold.

The geometric mean for hair-nickel levels in participants (0.64 ppm) was much greater than the

reference level (0.39 ppm) reported in the PRDOH manuscript. The PRDOH manuscript did not identify 

the source of this reference level. Sixty-three participants had hair nickel levels exceeding the 

laboratory’s 2-ppm threshold level. Of these, 80% were women. In addition, participants in age groups 

5–19 and 20–44 showed higher levels than did persons over 65 years. Risk factors associated with higher 

nickel hair levels included dyed hair, colorants and pigments use, and solvent use. Most of the elevated 

nickel levels in hair were probably from external contact via hair treatment.

3.7.2.2. PRDOH Discussion of Phase 1

At the total population level, the average concentration of some metals was above expected norms as 

established by Quest Laboratories (i.e., the laboratory’s reference value) but the average concentrations 

for the population were not above toxic levels as also stated by Quest Laboratories. The PRDOH

manuscript stated that this suggests the need for further investigation concerning the various risk 

factors, with particular emphasis on how smoking contributes to metal body burden. In addition, a 

better understanding is needed for how fish consumption affects metal body burdens, especially for 

arsenic and mercury. The PRDOH manuscript stated that eating fish within 3 days of a test or smoking 

could partly explain some but not all of the elevated metal body burdens in participants. The PRDOH

manuscript stated that smoking was associated with lead in blood, and arsenic and cadmium in urine. In 

addition, seafood consumption was associated with mercury in blood, and arsenic in hair and urine.

The PRDOH manuscript pointed out that the percentage of people with high metal levels who were 

neither exposed to tobacco smoke nor exposed from eating seafood was still greater than expected. For 

example, the PRDOH manuscript stated that 10% of nonsmokers had urine cadmium levels above 5 μg 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 77

cadmium per gram creatinine where only 5% was expected. The PRDOH report did not clarify whether 

these nonsmokers lived with smokers. Using information from the survey, the PRDOH manuscript 

identified factors or sources that were associated with elevated metals. These factors or sources include 

age, sex, hair dyes, and years living on Vieques, and soil contact, as well as working with petroleum 

products, solvents, metals, or animals. Table 9 from the PRDOH manuscript provides information about 

the estimated number of residents with elevated levels of metals in residents’ blood, urine, or hair. 

The PRDOH manuscript stated the following:

 Being an adult between the ages of 20 to 65 was associated with higher aluminum levels in 

blood.

 Being an adult over age 61 and working with animals was associated with higher arsenic in 

urine.

 Working with petroleum products was associated with higher blood lead levels.

 Contacting the earth’s crust and working with solvents was associated with higher cadmium in 

urine.

 Being a female; dying hair; using colorants, pigments, and solvents; and years living in Vieques 

was associated with higher nickel in hair.

What follows is Table 9 from the PRDOH manuscript.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 78

Table 9 from Heavy Metal Prevalence Study, Vieques, 2004

The PRDOH manuscript stated that further research was needed to understand how metal body burden 

in Vieques residents compared with Puerto Rico. In addition, research was needed concerning the 

possible long-term effects of high body burdens of metals in some Viequenses.

At the individual level, the PRDOH manuscript stated that according to Quest Laboratories, 15 persons 

showed toxic levels of metals:

 10 had toxic levels of aluminum in the blood, 

 Two had toxic levels of blood lead, 

 Two had toxic levels of cadmium in the urine, and 

 One had toxic levels of mercury in blood.

Quest recommended follow-up tests and medical examinations for these persons and investigation of 

their environments for possible metals sources.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 79

It is not clear why the PRDOH manuscript did not include the 117 persons who had arsenic urine levels 

that exceeded 50 μg/L (see Table 3A-2).

3.7.3. PRDOH Study, Phase 2

In Phase 2, from December 2005 to March 2006, the PRDOH study undertook follow-up activities on 15 

adults whose metal body burdens exceeded toxicity levels as identified by Quest Laboratories. Ten of 15 

agreed to participate. Blood samples were collected and measured for aluminum (6 persons), arsenic (3 

persons), lead (2 persons), and mercury (1 person)18. Arsenic blood tests included inorganic arsenic. 

Why the PRDOH study did not test urinary cadmium in the two persons with elevated urinary cadmium 

in Phase 1 is not clear. Why the PRDOH study did not measure speciated urinary arsenic in the 117 

persons with elevated urinary arsenic in Phase 1 is similarly unclear. LabCorp conducted the tests and 

provided the reference levels.

Of the six persons in Phase 1 with elevated aluminum in blood who agreed to retesting, none were 

elevated in Phase 2. Similarly, the one person with elevated blood mercury in Phase 1 was not elevated 

in Phase 2. Of the two participants from Phase 1 with elevated blood lead levels, one was elevated in 

Phase 2. The PRDOH manuscript stated that a follow-up investigation of the home environment for this 

person would take place. Table 3A-3 shows the results of Phase 2, although because of confidentiality 

issues, the PRDOH manuscript did not report the specific values. 

In addition to the 10 persons who participated in Phase 2 because they had high metal levels, the 

PRDOH manuscript included four additional residents who were not part of Phase I. These four residents 

volunteered for blood tests because they were interested in being tested. The PRDOH manuscript 

provides their results in the report but states that none showed levels considered potentially toxic.

 

18 Note that the number of tests is 12—some persons were apparently tested for more than one metal.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 80

Table 3A-3. PRDOH biomonitoring study Phase 2 biomonitoring results for 10 persons 

3.7.4. PRDOH Findings

The PRDOH manuscript reported that the main findings of this study were 

 In over 90% of the population, detectable levels were found of at least one heavy metal.

 In more than 20% of the study participants, the levels of aluminum in blood, arsenic in urine, or

nickel in hair were over the laboratory reference threshold.

 Geometric means for uranium in urine, mercury in blood, lead in blood, aluminum in blood, 

nickel in hair, and cadmium in urine were significantly higher than the geometric means from 

the 1999 NHANES survey. But the geometric means for mercury and aluminum in blood 

reported in the PRDOH manuscript were unreliable because of the high detection limit reported 

by the laboratory.

 None of the identified geometric means were over the toxicity threshold identified by the 

reporting laboratory.

 Cigarette use, hair dye use, and seafood consumption were identified as risk factors for levels 

above the laboratory threshold for arsenic, cadmium, and nickel.

 Fifteen persons (3%) were identified with levels above the toxicity threshold for aluminum in 

blood (10 persons), lead in blood (2 persons), mercury in blood (1 person), and cadmium in urine 

(2 persons).

 In the follow-up study on 10 persons with metal body burdens that exceeded toxicity levels, only 

one person with levels above the toxicity threshold was identified.

 Fewer than 4% of the participants showed elevated metal levels associated with possible 

development of signs and symptoms related to acute exposure. Among the metals studied, 

levels of aluminum in blood, nickel in hair, and arsenic in urine were reported with the greatest 

Metal

(Blood Samples)

Reference 

Threshold 

Level

NHANES

(4th Report)

Number of 

Persons 

Above Toxicity 

Level, Phase 1

Number of 

Persons Above 

Toxicity Level 

Geometric Phase 2

Mean

95th

Percentile

Aluminum 0 – 9 μg/L Not measured Not measured 6 0

Total Arsenic < 50+μg/L Not measured Not measured 3 2

Inorganic Arsenic 0 – 19 μg/L Not measured Not measured Not available 0/3

Lead 0 – 19 μg/dL 1.2 μg/dL 3.7 μg/dL 2 1 (Class III)

Mercury 0 – 14.9 μg/L 0.77 μg/L 4.6 μg/L 1 0

+ Table 1 (Phase II) in the PRDOH report is the source of the Reference Threshold Levels reported in 

Table 3A-3. The value of 50 μg/L appears to be a mistake as this level is often used for total urinary

arsenic.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 81

frequency as over the laboratory detection reference threshold. But the test for arsenic 

measured total arsenic, which includes nontoxic forms of arsenic from eating seafood (i.e., 

arsenobetaine and arsenocholine).

Multiple factors might account for these observations of elevated metals in blood, hair, and urine. For 

example, aluminum is abundant in soil worldwide. Average aluminum levels in LIA soils is 16,200 ppm 

compared with average aluminum in U.S. soils of 57,000 ppm. The absence of reference populations 

from Puerto Rico or information about aluminum levels in soils in Viequense residential areas limits 

interpretation of the aluminum results. The PRDOH manuscript also evaluated possible risk factors 

associated with elevated metal levels below the laboratory’s toxicity level—significant risk factors were 

in fact found. The PRDOH manuscript, however, points out that the study did not consider possible risk 

factors such as exposures from explosives, armaments, use of metal cooking utensils, metal residues 

that might be in foods such as tea and vegetables, consumption of drinks with metallic packaging,

antacid formulations, and antiperspirants.

In Phase 1, the PRDOH study measured total arsenic in urine, which consists of inorganic and organic 

arsenic. Because high levels of nontoxic organic arsenic are likely from seafood consumption, in Phase 2 

the PRDOH study measured total and inorganic arsenic for the three persons who had elevated total 

arsenic in Phase 1. No evidence of inorganic arsenic was found. The PRDOH manuscript pointed out that 

hair arsenic levels in the study participants were similar to the national average.

Nickel levels in urine in the study participants were similar to the national average. Sixty-three (63) 

persons had nickel levels in hair above the laboratory reference threshold. Hair dye, used by 27 of these 

63 persons (43%), and the use of colorants and solvents were identified as risk factors and thus possible 

sources of the nickel in hair. The PRDOH manuscript mentioned hair analysis’s inability to provide 

information about internal (i.e., ingestion) exposure versus external contact with metals (except for 

mercury). In addition, nickel measurements in hair do not predict that exposure will produce adverse 

health effects. 

The PRDOH manuscript also said the geometric means for aluminum (blood), mercury (blood), lead

(blood), uranium (urine), cadmium (urine), and nickel (hair) were higher than the national average (using 

NHANES and other reference sources); average levels, however, were not above toxicity levels cited by 

Quest Laboratories. The PRDOH manuscript identified three factors associated with increased arsenic, 

cadmium, and nickel in hair, urine, or blood: cigarettes , hair dye , and fish consumption. At the time of 

the study, seventy (15%) participants self-reported as smokers. Elevated lead levels were 4.75% more 

likely in smokers, who were also nearly two times as likely to have elevated levels of arsenic and nickel. 

The PRDOH manuscript added that the percentage of people with elevated levels of these metals who

were not exposed to cigarette use or consumption of seafood was still higher than expected. 

The study design attempted to use a stratified random sample of Viequenses who would represent the 

island’s population. But the PRDOH manuscript acknowledged the sample had a higher percentage of 

women, older persons, and the unemployed compared with the island’s population. The PRDOH

manuscript said this might have been due to interviews conducted during the day. Nevertheless, the 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 82

PRDOH study may have underrepresented fishers and island residents who worked during the day. The 

PRDOH manuscript agreed that the difference between the study population characteristics and the 

island characteristics limited generalizations of the data to all island residents.

The PRDOH manuscript also acknowledged that some of the tests failed to distinguish between the 

different forms of a metal. As mentioned previously, urine arsenic tests in Phase 1 failed to distinguish 

inorganic from organic arsenic. This also was the case for mercury. For uranium, laboratory tests failed 

to distinguish between natural uranium and depleted uranium.

3.7.5. PRDOH Actions Taken After Phase 1 and Phase 2

After completion of Phase 1, the following actions were taken:

 Dr. Luis Santiago gave a presentation of preliminary results to a group of about 15 Vieques 

community leaders.

 Participants’ results were provided to Dr. Mackenzie at the Vieques clinic. Of the 500

participants, 182 collected their results.

 Dr. Braulio Jimenez, a toxicologist with the University of Puerto Rico, gave three talks in Vieques 

about the signs and symptoms associated with exposure to heavy metals.

 A Phase 2 sampling was conducted to follow up on residents with toxic levels of metals.

 A working group was formed to analyze the studies conducted by the health department. This 

group came up with the suggestions for continuity and follow-up activities listed here.

3.7.6. PRDOH’s Suggested Follow-up Activities

The PRDOH manuscript suggested follow up with

 People identified with toxic levels of heavy metals,

 People with possible acute exposure to heavy metals,

 People with possible chronic exposure to heavy metals, and

 High-risk groups.

The PRDOH study used the CDC-provided recommendations to decide follow-up activities for the one 

remaining person with elevated blood lead levels after Phase 2 testing (CDC 1997; CDC 2002). The 

PRDOH study offered additional urine arsenic tests for those people who had elevated total urine 

arsenic in Phase 1. The follow-up tests measured inorganic arsenic. Inorganic arsenic levels in urine were 

within the laboratory reference levels (PRDOH 2006).

3.7.6.1. Follow up for people with possible acute exposure to heavy metals

The PRDOH manuscript stated that a protocol will be developed for the management of persons with 

suspected acute poisoning of heavy metals using CDC guidelines as a basis (CDC 1997; CDC 2002). It 

should be noted that CDC guidelines apply only to lead. The protocol will contain 1) training of local 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 83

health care providers, 2) ways to promote additional testing using the Commonwealth’s laboratory, 3) 

use of the poison center to provide recommendations for managing acute exposure victims, and 4) 

referral of suspected cases to the Medical Center of Puerto Rico.

3.7.6.2. Follow up for people with possible chronic exposure to heavy metals

The PRDOH manuscript suggested establishing a voluntary health registry for Vieques residents. A health 

registry would 1) allow for systematic documentation of factors related to potential risks, 2) identify 

people with early signs and symptoms that may be associated with illness, and 3) facilitate early care 

and health service access needs. The registry would gather demographic information, risk history, family 

history, past illness history, present status, and history of signs and symptoms associated with the 

chronic heavy metal exposure. A health registry could also provide comprehensive medical evaluations 

that include physical examinations with, among other tests, neurological examination and laboratory 

tests, including tests for kidney function, liver function, and CBC.

3.7.6.3. Follow up with a monitoring program for children under 6 years of age

Blood lead levels are unknown for the 1,000 Vieques children 6 years of age and younger—a high-risk 

group more vulnerable to lead exposure than are adults. This initial evaluation proposed in the PRDOH

manuscript will include all children 6 years of age and younger and will subsequently incorporate in 

future years an evaluation of children 1 and 2 years of age as part of their primary care. In 2006, when 

the report was written, the PRDOH manuscript stated that an epidemiologist would be appointed to 

work towards establishing this program, and this program will follow CDC guidelines for case 

management (PRDOH 2006). 

With funding from USEPA, PRDOH and CDC are currently conducting a prevalence study of blood lead 

levels in 1 to 5 year old children from mainland Puerto Rico. 

3.7.7. Investigations by Dr. Carmen Ortiz Roque

Dr. Carmen Ortiz Roque is a physician who has treated patients and conducted investigations on 

Vieques. In 2000, she began collecting hair samples from residents and had the samples analyzed for 

various metals. She has reported some of her results in unpublished manuscripts. In 2004 she published 

one peer-reviewed journal article.

3.7.7.1. Summary of Dr. Ortiz Roque’s 2004 Journal Article

In 2004, Dr. Ortiz Roque published the mercury data from her 2000/2001 hair study of Vieques residents 

(Ortiz Roque 2004). The study investigated hair mercury levels in women 16 to 49 years of age who lived 

on the island of Vieques and compared those levels with women from San Juan and Ceiba, Puerto Rico. 

Women with chemically treated hair within 3 months of the test were excluded. One of two licensed 

laboratories analyzed a 1.5-cm proximal hair sample.

Dr. Ortiz Roque reported statistics on 41 Viequense women together with information about seafood 

consumption and compared these data with mainland Puerto Rico and with results from the 1999 

NHANES survey in the United States. Table 3A-4 summarizes her data. Dr. Ortiz Roque used margin of 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 84

exposure (MOE) to define unsafe exposure levels. The MOE approach used by Dr. Ortiz Roque came 

from a 2001 MMWR article and the National Research Council. The formula for MOE is 5% effect level 

for mercury in hair / 90th percentile value for mercury in hair in the study population.

Table 3A-4. Mercury hair results in women published by Dr. Ortiz Roque in 2004.

# Age

Mercury in ppm

Margin of 

Exposure

Seafood Consumption

% women

Median Mean 90 > RfD

th

Percentile Total Local Local fish

Vieques 41 31.8 0.66 4.4 8.96 1.3 4.9 2.9 1.9 26.8

PR 45 29.9 0.38 0.4 1 12 2.8 1.1 0.7 6.6

USA (1999 

NHANES)

702 NA 0.2 1.4 8.6 NA NA NA 7

The National Research Council (NRC) recommended deriving the 5% effect level from the 95% lower 

confidence limit of a benchmark dose (BMDL05) that resulted in abnormal scores on cognitive function 

tests in children exposed to methylmercury in utero. The NRC recommended that the U.S.EPA derive 

their Reference Dose using a BMDL05 of 58 ppb methylmercury in cord blood, which was identified as 

the 5% effect level using statistical models from the Faroe Islands study. The 58-ppb cord blood 

translates to 12 ppm in hair (NRC 2000). Therefore, the MOE = 12 ppm / 90

th percentile mercury in hair. 

A MOE less than 1 means that for 10% of the study population the mercury level in hair is above the 5% 

effect level of 12 ppm, while an MOE greater than 1 means that for 90% of the study population the 

mercury level in hair is below the 5% effect level of 12 ppm (Ortiz Roque 2004; MMWR 2001). It is 

important to note that Dr. Ortiz Roque found three women with hair mercury levels greater than 12 

ppm, the level identified by the NAS as an effect level for the developing fetus.

Results showed that the 90th percentile mercury hair concentration in Vieques women was 8.96 ppm 

compared with 1 ppm in women from Puerto Rico and 1.4 ppm in women from the United States. With 

a MOE of 1.3, Dr. Ortiz Roque concluded that because hair mercury levels were close to the 5% effect 

level of 12 ppm, some Viequense women of reproductive age were exposed to mercury concentrations 

unsafe to their developing fetus. While ATSDR agrees with this conclusion, it should be noted that the 

percentage of Viequenses women with hair mercury levels above 12 ppm is uncertain because of the 

small and biased sample size in Dr. Ortiz Roque’s investigation.

Dr. Ortiz Roque also has unpublished data showing other metal concentrations in hair of Vieques 

residents. These data are summarized in Chapter 2.

3.7.8. Summary of Dr. Ortiz Roque 2002 Unpublished Manuscript 

3.7.8.1. Study Design

Dr. Carmen Ortiz Roque collected hair samples from 203 Viequenses from January 2000 to July 2001 

along with an extensive residential, occupational, nutritional, and health survey. Hair samples were 

analyzed for mercury, aluminum, cadmium, lead, and arsenic. The group consisted of 110 females and 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 85

93 males and ranged in age from 0.8 to 81 years. Participants were distributed among 18 neighborhoods 

on the island and were later informed of their individual hair results. Scalp hair samples were obtained 

from most participants. However, when scalp hair was limited or not available or hair was treated 

chemically, pubic or chest hair was collected (Ortiz 2002). Note that comparing results from pubic hair or 

chest hair with scalp hair may not be appropriate. Hair analysis were conducted by either the Mayo 

Medical Laboratory (Rochester, MN) or the King James Medical Laboratory (Cleveland, OH). 

3.7.8.2. Hair Study Results

Dr. Ortiz Roque reported the following results concerning metals in hair (Table 3A-5):

Table 3A-5. Results of metal analysis of hair samples collected from Viequenses from January 2000 to 

July 2001.

Metal

(sample

number)

% elevated Average in ppm

Overall 

(95% CI)

Females Males Children

<10 years old

Mercury

N= 205

33% > 1 ppm 2.07

(0–8.9)

2.87 1.08 1.89

Aluminum

N=145

56% > 17 ppm 25.74

(10.52–25.75)

26.45 24.18 34.94

Cadmium

N=205

26% > 0.47 

ppm

0.65

0–5.0)

0.75 0.55 Not available

Lead

N=205

2.9% > 25 ppm 8.07

(0–19.0)

4.28 12.47 Not available

Arsenic

N=205

0 > 1 ppm 0.18

(0–3.0)

0.141 0.233 Not available

Dr. Ortiz Roque stated that elevated levels of mercury (33%), aluminum (56%), cadmium (26%), and lead 

(2.9%) were found in hair samples from residents in Vieques. Hair arsenic levels were not elevated (Ortiz 

2002).

Dr. Ortiz Roque provided additional information about hair mercury in women and children, shown in 

Table 3A-6. She stated that 22% of women and 60% of children sampled in Vieques had mercury levels 

above the 90th percentile in the United States as identified from the 1999 NHANES national survey (Ortiz 

2002). Dr. Ortiz Roque further analyzed a subset of 22 Viequense matched pairs of mothers and their 

children 5 years of age or less. Dr. Ortiz Roque reported a significant correlation between mercury hair 

levels in mothers and their children (Pearson’s correlation 0.93, p = 0.0001). Dr. Ortiz Roque published 

these matched pairs in 2003 (see Table 3A-4).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 86

Table 3A-6. Viequense women and children mercury hair analysis compared with United States

Population Number % Population 

Sampled 2000

75th

percentile

ppm hair

90th

Percentile 

ppm hair

% above 90th

percentile for 

U.S. 

USA Women

16–49 years*

702 702/146,250,000

0.00048%

0.5 1.4 10%

Vieques women 45 45/4,594

0.97%

1.14 7.54 22%

USA Children*

1–5 years

338 338/19,175,798

0.00256%

0.4 10%

Vieques 

Children

1–5 years

38 38/771

4.9%

1.31 2.67 60%

* Reference ranges were derived from the 1999 NHANES survey

Dr. Ortiz Roque stated that the average aluminum hair concentration for Viequenses was 25.74 ppm. 

She reported that this concentration exceeded the upper limit of a standard human population, 

although the manuscript does not report the source of the upper limit. Dr. Ortiz Roque pointed out that 

aluminum levels in children’s hair was higher than in adults (Ortiz 2002). As stated previously, it is not 

possible to determine whether elevated levels of aluminum, cadmium, and lead in hair are from internal 

exposure via ingestion or inhalation or external exposure from direct contact of the hair with a metalcontaining commercial product. While Dr. Ortiz Roque’s data show that these metals are elevated in 

Viequenses at the 75th and 90th percentile, her population was not chosen randomly from the Vieques 

population. This nonrandom participant selection might account for some confounding factor elevating 

the rates. And for other metals, the nonrandom sample might account for the lower than expected 

metal concentrations.

3.7.8.3. Dr. Ortiz Roque’s Conclusions

Dr. Ortiz Roque maintained her data showed that Viequenses had internal exposure to heavy metals, 

supported by the high percentage of women and children with hair mercury levels above the 90th

percentile compared with the continental United States. While none of the women in the 1999 NHANES 

survey had mercury hair levels above 12 ppm, 3 of 45 Viequense women had hair levels above 12 ppm in 

Dr. Ortiz Roque’s survey (i.e., 15.41, 25.26, and 101.3 ppm) (Ortiz 2002).

In her 2002 draft manuscript, Dr. Ortiz Roque stated further that the positive correlation between 

mother and offspring hair showed that mercury exposure was occurring in utero; Viequenses’ exposure 

to mercury was too high to be considered safe; and mercury was used in explosive ordnance detonators 

(Ortiz 2002). The correlation between mother and offspring hair with seafood consumption is expected, 

has been shown in numerous human studies, and points to seafood as a major source of mercury in 

humans. The correlation of hair mercury levels in mother and children is not conclusive proof that these 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 87

children were exposed in utero. A study of mothers and newborns would be needed to make that 

statement conclusively. Assuming that mothers maintained similar fish-eating habits before and during 

their pregnancy, the positive hair mercury correlation between mother and offspring suggests that in 

utero exposure to mercury occurred and could occur in future pregnancies. While Dr. Ortiz Roque’s 

patients were not selected randomly, identifying several women with very high hair mercury levels is an 

important finding. 

3.7.9. Investigations by Dr. Carmen Colón de Jorge

Dr. Carmen Colón de Jorge also conducted human biomonitoring of metals in hair and in addition 

analyzed several stool samples for metals. Dr. Colón de Jorge collected hair and stool samples from 

Vieques residents in 1999 and 2000 and wrote a manuscript describing her results and findings (Colón

de Jorge, no date). 

Dr. Carmen Colón de Jorge began her manuscript by describing the case history of one of her patients 

who lived on Vieques. A 1991 hair analysis in a sick patient showed toxic levels19 of lead and aluminum 

according to the reporting laboratory. The patient was treated using naturopathic remedies, and the 

patient’s health improved. The patient was tested again in 1993 and again in 1996 because the patient 

was again sick. The hair tests showed high levels of lead, aluminum, and antimony. Arsenic and mercury 

were also present in hair. In 1999, toxic levels of aluminum, antimony, arsenic, and mercury were much 

higher as well, now showing toxic levels of cadmium and bismuth. The patient also had low levels of zinc 

and selenium and increased boron. Dr. Colón de Jorge stated the low levels of zinc and selenium 

confirmed endogenous poisoning with heavy metals. Representing the Scientific Committee of the 

Association of Licensed Naturopaths of Puerto Rico, Dr. Colón de Jorge collected hair and stool samples 

from Vieques residents in 1999 and 2000. She stated that the nutritional imbalance in residents as 

shown by hair analysis was evidenced by deficiencies in calcium, phosphorus, and magnesium and 

excessive boron in hair. She further stated that the decline in selenium, resulting from heavy metal 

contamination, was a contributor to cancer development.

3.7.9.1. Dr. Colón de Jorge’s Conclusions

Dr. Colón de Jorge stated that 45–50% of the people tested in Vieques were poisoned with mercury. 

Using results from stool samples, she found that 3 out of 6 children tested in Vieques had metal 

concentrations in stools20 above the reference range provided by the clinical laboratory (i.e., Doctor’s 

Data) that conducted the tests. She also reported that 5 out of 6 children tested had antimony and 

arsenic in stool samples that exceeded the laboratory’s reference range. She pointed out that children 

 

19 Dr. Colón de Jorge’s manuscript does not provide a definition for toxic level. Apparently Dr. Colón de Jorge used 

the term “toxic level” because it is used in the laboratory report provided by Doctor’s Data for potentially toxic 

elements. Although Doctor’s Data, Inc. also provides no “toxic level” definition, it appears to be any level above the 

95th percentile and is based on the laboratory’s observation of over 1 million hair samples. 

20 Determination of metals in stools samples is not a standardized or recommended means of determining 

exposure.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 88

could not be exposed to metals in paint, cigarette paper, tobacco, old pots, make-up, and hair dye as 

adults might be.

21 Uranium levels in children’s stool samples were below the reference range 

established by the laboratory.

Dr. Colón de Jorge reported that 30 hair samples were collected from Vieques residents with various 

health conditions:

 50% of the people tested were contaminated with antimony compared with 29% from a control 

population,

 50% of the people tested were contaminated with arsenic compared with 29% from a control 

population,

 50% of the people tested had a selenium imbalance.

 Dr. Colón de Jorge pointed out that antimony levels were high because antimony was used in 

explosive ordnance on Vieques, thus making the case that military exercises were the reason 

antimony levels were high. No supporting evidence, however, was provided to show how 

residents were exposed.

 Dr. Colón de Jorge also summarized the results of seven control patients with the following 

statements:

o None of the seven patients showed toxic levels. 

o Two cases had antimony above the reference range established by the laboratory compared 

with 29% of those investigated outside of Vieques. The selenium was normal for exogenous 

contamination.

o Two cases had arsenic above the reference range compared with 29% of the cases outside 

Vieques. The selenium is normal for exogenous contamination.

o The seven control patients exhibited no endogenous contamination with heavy metals—the

selenium was normal and within the reference range. According to Dr. Colón de Jorge, heavy 

metal contamination in a patient will often result in lower levels of selenium.

In summary, Dr. Colón de Jorge collected hair samples from seven random persons in Rio Piedras, a 

community on the main island of Puerto Rico. These persons’ health status remains unknown. None of 

the results show toxic levels of heavy metals, while 21 of 30 persons (i.e., 63%) from Vieques with 

known health conditions—and thus not randomly selected—showed toxic levels of various metals. As 

stated previously, current science is simply incapable of determining whether elevated levels of these 

metals in hair is from internal exposure via ingestion or inhalation, from external exposure via direct 

contact of the hair with a metal-containing commercial product, or due to accumulation secondary to an 

 

21 Note, however, that children can be exposed to lead in paint when they contact painted surfaces such as walls, 

doors, windows, stairs, and fences.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 89

underlying disease. The exception is that current science can determine whether mercury in hair is from 

internal or external exposure.

Dr. Colón de Jorge provided a report section that described the relationship between metal toxicities, 

which can cause mineral deficiencies and excesses, and the risk of various diseases and health 

conditions. This relationship, or risk pattern, is described for 1) cardiac conditions, 2) cardiovascular, 3) 

emotional disturbances, 4) violence 5) poor absorption, and 6) cancer.

3.7.9.2. Sample Results and Interpretation

Dr. Colón de Jorge summarized elemental levels in hair (Table 3A-7) and in stool samples (Table 3A-8). 

Dr. Colón de Jorge’s report contained several appendices with additional information, mostly focused on 

how to evaluate and interpret elemental results in hair. One of the appendices contained a report by 

Doctor’s Data entitled Comprehensive Interpretations for Hair Elements from Al to Zn.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 90

Table 3A-7. Summary of hair analysis of 30 samples as reported in Dr. Colón de Jorge’s unpublished 

(Colón de Jorge undated).

Metal

Range of levels 

in Dr. Colón de 

Jorge’s patients

in μg/g

Reference 

Range in Dr. 

Colón de 

Jorge’s 

manuscript*

Percent above

reference

Percent below

reference

Aluminum 4.4 – 68 <7 90

Antimony 0.016 – 2.7 <0.05 69

Arsenic 0.028 – 2.8 <0.06 66

Barium 0.23 – 4.7 0.026 – 3; 

0.16 – 1.6

14

21

3

Beryllium <0.001 <0.02 0

Bismuth 0.011 – 2.4 <0.06; 

<0.1

48

41

Boron 0.42 – 19 0.3 - 2

0.4 - 3

41

48

0

Calcium 145-2240 300 - 1200

200 - 750

17

24

24

Cadmium 0.024 – 0.98 <0.1

0.15

69

52

3

Zinc 64-630 140 - 220

130 - 200

21

24

28

14

Zirconium 0.012 - 0.76 0.02 - 0.42

0.02 - 0.44

7

7

3

0

Cobalt 0.008 – 0.16 0.013 - 0.05

0.013 - 0.035

14

28

21

Copper 8.9 – 110 12 - 35

10 - 28

31

35

21

3

Chromium 0.2 – 0.69 0.2-0.4 10 0

Tin 0.08 – 1.3 <0.3 66
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 91

Metal

Range of levels 

in Dr. Colón de 

Jorge’s patients

in μg/g

Reference 

Range in Dr. 

Colón de 

Jorge’s 

manuscript*

Percent above

reference

Percent below

reference

Strontium 0.29 – 9 0.5 - 7.6

0.3 - 3.5

7

28

17

3

Germanium 0.022 – 0.082 

(12 N/A)

0.045 - 0.0.65 

(sic)

18 77

Iron 6.4 – 70 5.4 - 14

5.4 - 13

52

62

0

Lithium 0.005 – 0.056 0.007 - 0.023 7 66

Magnesium 23 – 560 35 - 120

25 - 75

31

52

21

3

Manganese 0.21 – 4.8 0.15 - 0.65 31 0

Mercury 0.06 – 3.1 <1.1 38

Molybdenum 0.02-0.12 48

31

10

3

Nickel 0.05 - 2.9 <0.4 28

Silver 0.01 - 1.7 <0.14; <0.12 21

35

Platinum <0.003

<0.005

0

Lead 0.34 – 26

<0.1;<2

55

35

Rubidium 0.018 – 0.38

0.007 – 0.096; 

0.11 – 0.12

28

24

0

0

Selenium 0.52 – 2.5

0.95 – 1.7

3

Thallium <0.001 – 0.005 <0.01 0
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 92

Metal

Range of levels 

in Dr. Colón de 

Jorge’s patients

in μg/g

Reference 

Range in Dr. 

Colón de 

Jorge’s 

manuscript*

Percent above

reference

Percent below

reference

Thorium <0.001 <0.005 0

Uranium <0.001 – 0.021

(<0.06)

0

Vanadium 0.013 – 1.2

(0.018 – 0.065)

38 3

* Reference values provided by Doctor’s Data, Inc., St. Charles, IL. For several elements, the laboratory reported 

two reference ranges on different samples.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 93

Table 3A-8. Summary of the results of feces analysis as reported in Dr. Colón de Jorge unpublished 

manuscript (Colón de Jorge undated).

Metal

Range in Dr. Colón de 

Jorge’s patients in 

μg/g

(Reference range)

Reference 

Range* Percent

above

reference

Percent

below

reference

Aluminum 43-750 130 57 42

Antimony 0.06 – 0.127 NA 83 16

Arsenic 0.098 – 0.866 NA 83 16

Beryllium 0.01 – 0.012 (2 < dl) * NA 50 50

Bismuth 0.014 – 0.55 NA 50 50

Cadmium 0.14 – 1 0.47 14 86

Copper 17 – 68 50 14 86

Mercury 0.028 – 0.1

(0.02 with no 

amalgam)

(0.26 with amalgam)

0.02 with no 

amalgam

0.26 with 

amalgam

100

0

0

100

Nickel 3.4 – 7.5

(4.4)

4.4 86 14

Platinum 2.92 (6< dl) a NA 16 84

Lead 0.23 – 0.59 0.75 30 100

Thallium 0.005 – 0.015 NA 0 100

Tungsten 0.014 –0 0.475 NA 50 50

Uranium 0.025 – 0.061 NA 0 100

*Reference values provided by Doctor’s Data, Inc., St. Charles, IL. 

dl = detection limit

NA = not available

3.7.10. Investigations by Dr. Carlos Rodríguez Sierra

On October 30, 2009, Dr. Carlos Rodríguez Sierra gave a presentation at Casa Pueblo de Ajuntas that was 

broadcast via the Internet. Dr. Rodríguez Sierra discussed arsenic in fish and biomonitoring data 

concerning urine arsenic levels in Viequenses. Among the 162 fish from 8 species that he collected, he 

said only arsenic exceeded the international criterion of 2 μg arsenic per gram fish wet weight.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 94

In July 2006, he also collected biological samples from 52 adults, whom he divided into two groups: a 

high fish-consumption group (n=30) and a low fish-consumption group (n=22). He collected hair, nail, 

and urine samples. Urine samples were measured for total arsenic and for various arsenic species: 

 Trivalent arsenic (As III)

 Pentavalent arsenic (As V)

 Monomethylarsensonic acid (MMA), 

 Dimethylarsenonic acid (DMA), and 

 Arsenobetaine. 

The inorganic arsenic species are AsIII and AsV and their organic metabolites (MMA and DMA). The 

following data were presented:

Minimum Median 75th 95th max

22

Total As 5.33 22.54 33.7 161.69 1414

Arsenobetaine 

ug/g creatinine 0 7.64 22.26 141.63 1373

Total inorganic arsenic was compared with the 2003-2004 NHANES results of the U.S. population:

N Median 95th

Vieques 52 10.3 35.3

NHANES 2557 6.0 18.9

Dr. Rodríguez Sierra announced these conclusions from his analysis of arsenic in residents of Vieques:

1. High levels of arsenic in hair, nails, and urine were not detected at the time of sampling

a. Hair and nail sample levels were below the reference values of 1 ug/g,

b. The sum of the inorganic arsenic species and its metabolites was less than 50 ug/g 

creatinine, which was used as a reference value.

2. Levels of inorganic arsenic in urine samples from Vieques are slightly above the median and 95th

percentile levels reported in 2003–2004 NHANES.

Dr. Rodríguez Sierra has informed ATSDR that he plans to publish these data in 2011; more complete 

information should then become available.

 

22 ATSDR is unsure of the maximum level of total arsenic and arsenobetaine reported during Dr. Rodríguez Sierra’s 

presentation.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 95

3.8. Appendix 3-B. Biomonitoring 

The NHANES Fourth National Report on Human Exposure to Environmental Chemicals (The 4

th Report) 

provides biomonitoring data for the U.S. population for the years 1999–2004. The 4

th Report also 

provides geometric mean, 50th, 75th, 90th, 95th percentile as well as statistics by the following age groups, 

sex, race, and ethnicity:

 6–11

 12–19

 20 years of age and older

 Mexican-American

 Non-Hispanic blacks

 Non-Hispanic whites

The 4

th Report contains toxicological information about metals when available. The report is now 

available at: http://www.cdc.gov/exposurereport. The 4th Report also contains summary statistics from 

previous NHANES surveys that cover 1999–2000 and 2001–2002. Table 3B-1 provides a brief summary 

of statistics (CDC 2009).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 96

Table 3B-1. FourthNational Report on Human Exposure to Environmental Chemicals: urine and blood 

levels toxicity

Metal Media Year Geometric Mean 95th Percentile Age

Antimony Urine 99-00 0.132 ug/L 0.42 ug/L 6 and older

01-02 0.134 ug/L 0.34 ug/L

03-04* -- 0.28

99-00 0.124 ug/g 0.382 ug/g

01-02 0.126 ug/g 0.364 ug/g

03-04* -- 0.277 ug/g

Total Arsenic Urine 03-04 8.3 ug/L 65.4 ug/L 6 and older

03-04 8.24 ug/g 50.4 ug/g

Arsenobetaine Urine 03-04 1.55 ug/g 35 ug/g 6 and older

03-04 1.54 ug/g 29.4 ug/g

Barium Urine See 

report

See report See report

Beryllium Urine See 

report

See report See report

Cadmium Urine 99-00 0.193 ug/L 1.2 ug/L 6 and older

01-02 0.210 ug/L 1.2 ug/L

03-04 0.211 ug/L 1.15 ug/L

99-00 0.181 ug/g 0.993 ug/g 6 and older

01-02 0.199 ug/g 0.917 ug/g

03-04 0.21 ug/g 0.94 ug/g

Blood 99-00 0.412 ug/L 1.3 ug/L 1 and older

01-02* -- 1.3 ug/L

03-04 0.304 ug/L 1.6 ug/L

Cesium Urine See 

report

See report See report

Cobalt Urine See 

report

See report See report

Lead Blood 99-00 1.66 ug/dL 4.9 ug/dL 1 and older

01-02 1.45 ug/dL 4.4 ug/dL

03-04 1.43 ug/dL 4.2 ug/dL

Urine 99-00 0.766 ug/L 2.9 ug/L 6 and older

01-02 0.667 ug/L 2.9 ug/L
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 97

Metal Media Year Geometric Mean 95th Percentile Age

03-04 0.636 ug/L 2.29 ug/L

99-00 0.721 ug/g 2.37 ug/g 6 and older

01-02 0.639 ug/g 2.03 ug/g

03-04 0.632 ug/g 1.97 ug/g

Total 

Mercury**

Blood 99-00 0.343 ug/L 2.3 ug/L 1-5 year old

01-02 0.318 ug/L 1.9 ug/L 1-5 year old

03-04** 0.326 ug/L 1.8 ug/L 1-5 year old

99-00 1.02 ug/L 7.1 ug/L 

females

16-49 years

01-02 0.833 ug/L 4.6 ug/L 

females

16-49 years

03-04 Not available Not available Not available

For women 

16-49

03-04 0.979 ug/L 4.9 1 and older

Urine 99-00 0.719 ug/L 5.0 ug/L 16-49 years

01-02 0.606 ug/L 3.99 ug/L 16-49 years

03-04 Not available Not available Not available 

for women 

16-49

03-04 0.447 ug/L 0.319 ug/L 1 and older

99-00 0.71 ug/g 3.27 ug/g 

females

16-49 years

01-02 0.62 ug/g 3.0 ug/g 

females

16-49 years

03-04 Not available Not available Not available

For women

03-04 0.443 ug/g 2.35 ug/g 1 and older

Molybdenum Urine See 

report

See report See report

Platinum Urine <LOD <LOD

Thallium Urine 99-00 0.176 ug/L 0.45 ug/L 6 and older

01-02 0.165 ug/L 0.44 ug/L

03-04 0.155 ug/L 0.44 ug/L
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 98

Metal Media Year Geometric Mean 95th Percentile Age

99-00 0.166 ug/g 0.366 ug/g 6 and older

01-02 0.156 ug/g 0.348 ug/g

03-04 0.154 ug/g 0.350 ug/g

Tungsten Urine See 

report

See report See report

Uranium Urine 99-00 0.008 ug/L 0.046 ug/L 6 and older

01-02 0.009 ug/L 0.046 ug/L

03-04 0.008 ug/L 0.039 ug/L

99-00 0.007 ug/g 0.034 ug/g 6 and older

01-02 0.008 ug/g 0.04 ug/g

03-04 0.008 ug/g 0.029 ug/g

* A large percentage of participants had < LOD, thus preventing the calculation of an overall mean

** Additional information about mercury levels in blood for various age groups is now available from a 2003–2006 

survey. These data are summarized in Caldwell KL et al, “Total blood mercury concentrations in the U.S. 

population: 1999–2006.” Int J Hyg Environ Health 2009 (Nov) 212;6:588–98. 

Note: Total blood mercury was measured in children aged 1–5 years and in women aged 16–49 years in 1999–

2002. Total blood mercury and inorganic blood mercury were measured in all participants aged 1 year and older in 

2003–2004. Urinary mercury was measured in women aged 16–49 years in 1999–2002. For the 2003–2004 survey, 

urinary mercury was measured in a random one-third subsample of participants aged 6 years and older.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 99

4. Health Outcome Data

4.1. Public Health Data Systems and Programs............................................................................. 100

4.2. Assessment of Available Public Health Data .......................................................................... 101

4.2.1. Cancer.......................................................................................................................... 101

4.2.2. Noncancer.................................................................................................................... 102

4.3. Findings................................................................................................................................... 105

4.4. Conclusions and Recommendations....................................................................................... 107

4.4.1. Conclusions.................................................................................................................. 107

4.4.2. Recommendations....................................................................................................... 107

4.5. References.............................................................................................................................. 107

Chapter 4 Summary

Assessing accurately the health status of Viequenses requires quantifying morbidity and 

mortality as well as identifying possible factors that may lead to adverse health outcomes. 

Quantifying morbidity and mortality and assessing possible contributing factors can help to 

identify specific opportunities for intervention in public health programs or delivery of 

health services. An understanding of public health data collection and reporting systems, 

public health programs, and the health care delivery system on the island of Vieques is 

required to determine future activities for improving the health status of Viequenses.

In this chapter we review public health data collection and reporting systems used in 

quantifying morbidity and mortality, review several reports published in the last 10 years 

that assess morbidity and mortality in Vieques, and provide a brief review of available 

health services on Vieques. All of these studies are descriptive in nature and provide some 

insight into the Vieques health picture. The studies do not contain analyses that relate

potential environmental or other factors to the identified health conditions. Because of the 

small population, all studies suffer to some degree from a lack of statistical power and 

methodological limitations that make interpretation difficult. Despite these limitations, the 

studies are valuable for describing the health status of Viequenses. And in Vieques relative 

to the rest of Puerto Rico, the studies indicate elevations in the prevalence of chronic 

disease, cancer incidence, and cancer mortality.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 100

4.1. Public Health Data Systems and Programs

The primary data systems supporting the estimation of incidence and prevalence of health outcomes in 

Puerto Rico are the Central Cancer Registry (RCCPR), Behavioral Risk Factor Surveillance System (BRFSS), 

Birth Defects Surveillance System (BDSS), and the Puerto Rico Vital Records Office. CDC helps to fund 

each of these data collection and reporting systems. Their strengths and weaknesses affect data quality 

and the resulting ability to develop appropriate public health actions based on this information. 

The data reported by the RCCPR have several strengths. Cancer registries typically represent the best 

population-based dataset when compared with data collection systems and associated datasets for 

other chronic diseases. Most cancer cases are captured by registries due to legal reporting 

requirements, redundancies in the reporting system (i.e., reporting by labs, clinics, hospitals, and 

specific oncologists), and the clinical course of cancer that usually requires substantial follow up and 

repeat visits. The analysis of cancer registry data should then represent the most accurate assessment of 

cancer incidence in Vieques. Finally, through a cooperative agreement in place since 1998, CDC has 

continuously funded the cancer registry. And the registry’s data accuracy has steadily improved. 

That said, however, several weaknesses in the registry data should be noted. First, funding has been 

inconsistent throughout the life of the registry, but recently it has become more stable. The RCCPR was 

funded in part by the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) 

Program from 1973–1989. The contract between the RCCPR and SEER was not renewed, and until 1997 

RCCPR operated on local funding. In 1997, the RCCPR applied for and received funding from the Centers 

for Disease Control and Prevention (CDC) through a cooperative agreement via the National Program of 

Cancer Registries. The RCCPR provided data to the CDC beginning with cancer cases diagnosed in

calendar year 1998. Completeness and timeliness have also been problematic due to a shortage of 

trained personnel to perform cancer abstracting and delays in reporting by facilities because of lack of 

funds and lack of reporting requirements by some facilities. The RCCPR has made significant progress 

toward improving completeness. In 2003, a CDC review concluded that 95.3% of all cancer cases 

diagnosed or treated in hospital facilities in Puerto Rico were appropriately reported to the RCCPR; a 

result comparable to the US median (95%).

BRFSS is the primary surveillance system for estimating the prevalence of chronic diseases and health 

behaviors in the United States and in Puerto Rico. BRFSS is the primary data source for prevalence 

estimates of asthma, diabetes, hypertension, and heart disease. One limitation of this system is the 

ability to provide accurate prevalence estimates in small populations. Vieques has a population of less 

than 10,000 residents. Providing accurate prevalence estimates is difficult in populations this small. This 

is particularly due to the complex survey design and the overarching goals of producing state and 

national prevalence estimates. The Selected Metropolitan/Micropolitan Area Risk Trends (SMART) 

project was initiated to develop prevalence estimates at the local level. The SMART project utilizes 

methods to develop prevalence estimates using BRFSS data for areas with 500 or more respondents. 

These methods may represent a viable option for using BRFSS to develop prevalence estimates for 

Vieques.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 101

CDC funds the Puerto Rico BDSS, which tracks thirteen congenital conditions diagnosed at birth. Current 

program goals include expanding the capacity of the surveillance system to identify birth defects cases 

and developing legislation that mandates the reporting of birth defects in Puerto Rico to the BDSS. The 

BDSS is one of 14 CDC-funded birth defects surveillance systems. The population-based system uses 

active case ascertainment. Abstractors in each public health region visit hospitals and other facilities to 

review medical records to identify cases for each specific type of birth defect. Although this approach is 

considered the gold standard, it is resource-intensive. A limitation of birth defects surveillance in general 

is that some defects cannot be diagnosed at birth and thus go undetected.

Another morbidity and mortality data source is the Puerto Rico Vital Records Office. The Vital Records 

office collects data on births and deaths for the entire population. Advantages of birth and death data 

include low cost, availability, and, because of the statutory reporting requirements, near-complete 

coverage. Mortality data limitations include multiple causes of death, completeness of records, and 

changes in diagnostic practices from improvements in medical technology (Rothman and Greenland 

1998). Birth certificate data limitations include changes to birth certificates over time, incomplete birth 

certificates, and self-reported information. 

4.2. Assessment of Available Public Health Data

Several studies have evaluated morbidity and mortality in the Viequense population. All are descriptive 

in nature and provide some insight into the health of that population. But these studies do not contain 

analyses that relate potential environmental or other factors to the identified health condition. In 

addition, because of the small study population, all the studies suffer from a lack of statistical power. 

Despite their limitations, these studies are valuable for describing the health status of Viequenses and 

providing insight that will inform next steps. An evaluation of studies published within the past decade 

are summarized and discussed in this chapter. Conclusions and recommendations for further action are 

outlined below and in Chapter 9. These recommendations are viewed as a starting point for dialogue 

with the scientific community and Viequenses to develop an action plan that will help improve 

Viequenses’ health.

4.2.1. Cancer

The RCCPR released reports in 2006 and 2009 detailing cancer incidence and mortality in Puerto Rico. 

The 2006 report evaluated cancer incidence and mortality from 1990–2001. In contrast, the 2009 report 

evaluated cancer incidence and mortality from 1990–2004. Both studies assessed whether, using similar 

methods, cancer incidence and mortality rates were higher in Vieques than in the main island of Puerto 

Rico. The standardized incidence and mortality ratios with 95% confidence intervals were calculated. 

The authors defined statistical significance as a 95% confidence interval that did not include 1. Similarly, 

the authors defined marginal statistical significance as a 90% confidence interval that did not include 1. 

The analyses have several strengths. Most cancer cases are captured by registries. This is because of 

legal reporting requirements, redundancies in the reporting system (i.e., reporting by labs, clinics, 

hospitals, and specific oncologists), and the clinical course of most cancers that requires substantial 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 102

follow up and repeat visits. The analysis of cancer registry data should then represent the most accurate 

assessment of cancer incidence on Vieques. 

Although the analyses have several strengths, several limitations were also noted. As mentioned briefly 

in the PRDOH reports and confirmed by Dr. Figueroa (personal communication, July, 2009), some follow

up to identify cases in Vieques occurred that was not uniformly applied across the rest of Puerto Rico. 

One example is related to the documentation of age for cases in the registry. 

For both assessments, all cases indicating residence on the Island of Vieques were age-confirmed. This 

practice was not mirrored on the main island of Puerto Rico. If a case did not have a known age, it was 

not included in any rate calculations. In addition, cases were actively sought in Vieques and not in the 

rest of Puerto Rico. This potentially introduces bias; it omits cases from the reference population (i.e., 

Puerto Rico) and increases the proportion of cases captured by the registry in Vieques relative to Puerto 

Rico, thus potentially, artificially inflating standardized incidence ratios. Other differential methods for 

seeking out and reviewing cases in Vieques not applied on the main island would similarly bias the 

results (RCCPR 2006, 2009). 

4.2.2. Noncancer

We reviewed two studies that evaluated noncancer data. The primary noncancer morbidity study was 

released in March 2000 by Yadiris Lopez and Crisarlin Carrosquillo (Lopez and Carrosquillo 2002). We 

also reviewed noncancer mortality in “Heavy metal exposure and disease in the proximity of a military 

base” by Dr. Carmen Ortiz Roque (Ortiz Roque 2002). 

The Lopez and Carrosquillo survey was conducted because of growing concerns regarding 

environmental contamination from the past military activities and their potential adverse human health 

effects on Viequenses. The survey was a cross-sectional design with a sample size of 1,043. The field 

work for the study was conducted between April and November of 2000. Lopez and Carrosquillo 

attempted to include all residents in each neighborhood and allowed the head of a household, typically 

the matriarch, to provide proxy responses for all household members. The survey collected data on 

demographics, employment history, and dietary habits, along with self-reported disease prevalence. 

The overall age distribution of the sample selected, based on 1990 and 2000 U.S. census data, appears 

older than the Vieques population. Lopez and Carrosquillo reported that 36% of the sample was ages 60 

and older. Data from the 1990 U.S. Census indicated that 16% of the Vieques population was 60 years 

and older. Similarly, the 2000 Census indicated that 19.5% of the Vieques population was 60 years and 

older. Participants were selected from Lujan, Puerto Rico Reconstruction Administration, Santa Maria, 

and Esperanza. The 132 residents of Lujan reported an age range of 5–25, whereas the 306 residents of 

the Puerto Rico Reconstruction Administration (PRRA) reported an age range of 59–70. The age 

distributions of Santa Maria and Esperanza were not reported separately. These neighborhoods were 

collectively described as "representative” of the Vieques population but appear to be older. 

The survey participants identified 28 medical conditions. These conditions are listed in Table 4-1. Of the 

28 medical conditions identified by participants, the authors presented comparisons using risk ratios for 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 103

six health conditions: cancer, heart disease, hypertension, diabetes, asthma, and arthritis. The 

prevalence of health conditions was compared with the expected number of cases, calculated by 

multiplying the population of Vieques by the percentage of cases that occurred in the 1994 Puerto Rico 

Chronic Morbidity Study (PRCMS). In addition to medical conditions, the authors described the 

frequency of cigarette use, alcohol consumption, eating habits, and abortions. The authors stated that 

cancer was not connected to cigarette smoking or alcohol consumption—the frequency of each factor in 

the survey was similar to the totality of Puerto Rico. The frequency of cigarette use and alcohol 

consumption among participants with the most prevalent health conditions was not presented (Lopez 

and Carrosquillo 2002). 

Table 4-1. Viequenses-reported health conditions

Health Conditions Number of Cases Percentage

High Blood Pressure 189 18.1

Asthma 112 10.7

Diabetes 102 9.8

Arthritis 89 8.5

Heart Disease 77 7.4

Skin Conditions 61 5.8

Sinusitis 56 5.4

High Cholesterol 54 5.2

Muscular Spasms 52 5.0

Allergies 49 4.7

Other 36 3.5

Circulation 36 3.5

Stress 32 3.1

Migraine 24 2.3

Cancer 19 1.8

Anemia 16 1.5

Kidneys 14 1.3
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 104

Health Conditions Number of Cases Percentage

Uric Acid 13 1.2

Epilepsy 11 1.1

Tumor 10 1.0

Prostate 10 1.0

Fatigue 10 1.0

Nodules 5 0.5

Pneumonia 4 0.4

Lead in blood 4 0.4

Osteoporosis 3 0.3

Lupus 1 0.1

Spinal Column Deviation 1 0.1

Dr. Ortiz Roque briefly presented noncancer mortality and infant mortality in a report. In January 2002, 

Dr. Ortiz Roque, together with the College of Physicians and Surgeons in San Juan, PR, released a report 

entitled “Heavy metal exposure and disease in the proximity of a military base.” This effort was initiated 

because of community concern that past military activities on the island may have adversely affected 

Viequenses’ health. Ortiz Roque reported mortality statistics from the Puerto Rico Department of Health 

for 1991–1998. Age standardized mortality data between Vieques and mainland Puerto Rico were 

compared with total deaths and cause-specific deaths. Additionally, infant mortality rates in Vieques 

were also compared with those of Puerto Rico for 1975–1995 (Ortiz Roque 2002). 

The mortality data presented did not enumerate all analyses performed—only those that were elevated. 

Finally, infant mortality is only briefly mentioned, and to ascertain specific times is difficult, especially 

those for specific causes.

Symptom-disease prevalence surveys of a population, such as the Lopez and Corrosquillo survey, are 

useful hypothesis-generating tools. This is especially true when little preexisting knowledge is available 

regarding the population’s potential exposures and associated health effects. Another strength of the 

Lopez and Carrosquillo survey was its large sample size (n=1,043) relative to a population of 

approximately 10,000. Mortality data may also provide meaningful insight into the health status of 

Viequenses. Analyses of mortality patterns in a population can be useful for hypothesis generation; 

however, using these data to quantify potential relationships in exposure-disease relationships is 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 105

difficult. Many potential confounding variables cannot be assessed (e.g., access to care, lifestyle factors, 

and dietary habits). Typically, mortality data are population-based, with near universal coverage, and 

are less prone to bias. 

Despite such strengths, however, symptom-disease prevalence surveys and the mortality data reviewed 

have several limitations. Their ability is restricted to test inferences regarding associations between 

exposure and health status. They assess exposure and disease simultaneously; thus to determine 

whether the exposure preceded the disease is not possible. Because these surveys rarely contain 

quantitative exposure data—either through direct contaminant measurements in a participant’s 

immediate environment or through biomonitoring—using this approach to understand the relationship 

between exposure and health status is inherently difficult. The Lopez and Carrosquillo symptom 

prevalence survey, for example, did not include environmental exposure information. In addition, cross 

sectional surveys of symptom-disease prevalence are often severely compromised by reporting bias 

from participants’ real or perceived problems. For the Lopez and Corrosquillo survey, all data were selfreported or reported via proxy, with no attempt to validate the information using medical records. In 

such cases, the analysis would benefit from a medical records review to validate self-reported data. 

A third limitation of this survey was a lack of statistical power. The sample was large relative to the 

population, but still may have lacked the power necessary to identify differences in the observed 

frequencies and, for many health conditions, in the expected frequencies. Confidence intervals, with risk 

ratio estimates to identify differences, were not presented. 

4.3. Findings

 Access to oncology and other specialty services (e.g., neurology, cardiology) requires travel to 

the main island of Puerto Rico.

 Analyses of data from the RCCPR (cancer incidence) and the Vital Statistics office (cancer 

mortality) identified some statistically significant elevations. Statistically significant results 

(α=0.05) from these analyses are presented in the following tables: 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 106

Table 4-2. Summary of Statistically Significant Standardized Incidence Ratios for Cancer 

Outcome Period Group SIR, 95% CI

All cancers 1990 – 1995 Men and Women together 1.19 (1.02, 1.39)

Lung and bronchus 1990 – 1995 Men and Women together 2.25 (1.35, 3.52)

Lung and bronchus 1990 – 1995 Men 2.24 (1.19, 3.83)

Prostate 1990 – 1995 Men 1.47 (1.03, 2.03)

All cancers 1995 – 1999 Men and Women together 1.26 (1.08, 1.47)

All cancers 1995 – 1999 Men 1.31 (1.07, 1.60)

Prostate 1995 – 1999 Men 1.53 (1.09, 2.09)

Table 4-3. Summary of Statistically Significant Standardized Mortality Ratios for Cancer 

Outcome Period Group SMR, 95% CI

All cancers 1990 – 1995 Men and Women together 1.26 (1.01, 1.57)

All cancers 1990 – 1995 Women 1.43 (1.01, 1.96)

Breast 1990 – 1995 Women 0.26 (0.03, 0.92)

Colorectal 1990 – 1994 Women 2.75 (1.11, 5.67)

Oral Cavity and Pharnyx 1990 – 1995 Men 3.96 (1.08, 10.0)

All cancers 1995 – 1999 Men and Women together 1.35 (1.08, 1.67)

All cancers 2000 – 2004 Men 1.40 (1.07, 1.80)

Prostate 2000 – 2004 Men 2.62 (1.66, 3.93)

 When compared with all of Puerto Rico, the Lopez and Carrosquillo survey indicated an 

increased occurrence in Vieques of hypertension, asthma, diabetes, heart disease, and some 

cancers. A key survey limitation is the lack of supporting medical record inspection to support 

self-reported claims and to reduce the possibility of information bias. 

 An increase in infant mortality was also reported and increases in noncancer mortality for 

hypertension, cirrhosis, and diabetes.

Vieques has a population of approximately 10,000. Typically, around 30 new incident cases and 15 

deaths for all cancers combined occur annually. Therefore, statistical power to detect any meaningful 

differences in cancer incidence on the island is low when evaluating specific anatomical sites, short time 

frames, or both. Assessing rates over a longer time span would be useful rather than the traditional 5 

years, as in standard cancer surveillance publications. As differential ascertainment for the Vieques 

residents probably biased the presented, standardized incidence ratios, uniform case identification 

methods should be applied across all study and referent populations
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 107

4.4. Conclusions and Recommendations

4.4.1. Conclusions

1. The documents ATSDR reviewed paint a complex health picture for Viequenses. The findings of 

these reports indicate elevations in chronic disease prevalence, cancer incidence, and cancer 

mortality among the population between Vieques and the rest of Puerto Rico. In addition, 

increased mortality in Vieques particularly from cancer may indicate lack of access to 

appropriate medical care. The limitations associated with these analyses, particularly the

methodological concerns discussed in this report, introduce considerable uncertainty and make 

interpretation difficult. Some of the methodological concerns previously noted include more 

exhaustive cancer case finding in Vieques than the rest of Puerto Rico, differential follow-up, 

chronic disease prevalence estimates based on a symptom disease prevalence survey without 

medical record confirmation of health outcomes, and limited noncancer mortality data. 

Differential follow up and exhaustive case finding may result in biased estimates of cancer 

incidence and mortality. Uncertainty is also evident in the wide confidence intervals reported 

indicating imprecise estimates of cancer incidence and mortality ratios in Vieques relative to the 

rest of Puerto Rico (RCCPR 2009). This is not unusual when calculating estimates for small 

populations. 

2. These findings can nonetheless serve as a guide for future investigations of Viequenses’ health 

status.

4.4.2. Recommendations

Assess the feasibility of applying the SMART BRFSS methods for generating stable Vieques specific 

prevalence estimates on asthma, diabetes, hypertension, and other chronic diseases.

4.5. References

Commonwealth of Puerto Rico Department of Health. 2005. Needs Assessment 2005–2010 Puerto Rico 

Title V Application 2005–2006.

Commonwealth of Puerto Rico Department of Health. 2006. Cancer incidence and mortality in Vieques 

1990–2001.

Commonwealth of Puerto Rico Department of Health. 2009. Cancer incidence and mortality in Vieques 

1990–2004.

Lopez Y, and Corrosquillo C. 2002. Exploratory study of health and other conditions in Vieques. 

ORC MacroSM. National Program of Cancer Registries, Technical Assistance and Audit Puerto Rico 

Central Cancer Registry 2000, Case Completeness and Data Quality Audit.

Ortíz Roque C. 2002. Heavy metal exposure and disease in the proximity of a military base. San Juan, 

Puerto Rico: College of Physicians and Surgeons

Puerto Rico Cancer Control Coalition. 2008. Puerto Rico Comprehensive Cancer Control Plan 2008–2012.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 108

Rothman K and Greenland S. 1998. Modern epidemiology. Philadelphia PA: Lippincott-Raven. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 109

5. Local Produce and Livestock Pathway

5.1. Introduction............................................................................................................................ 110

5.2. Assessment of Available Data................................................................................................. 110

5.2.1. Studies from 2000–2002 ............................................................................................. 110

5.2.2. Studies from 2003........................................................................................................ 113

5.2.3. Studies from 2004–2005 ............................................................................................. 117

5.2.4. Studies from 2008........................................................................................................ 118

5.3. Conclusions and Recommendations....................................................................................... 118

5.3.1. Conclusions.................................................................................................................. 118

5.3.2. Recommendations....................................................................................................... 119

5.4. References.............................................................................................................................. 120

Chapter 5 Summary

This chapter evaluates available data and information on contaminants detected in local garden 

produce and livestock; Chapter 7 considers the effects of direct contact with soil contaminants.

The overall data are insufficient to quantify adequately human exposures or draw any valid health 

conclusions about whether consuming locally grown produce and livestock would result in harmful 

health effects. 

Limited sampling data are available for pigeon peas, a staple food among Viequenses. A preliminary 

data evaluation completed for this report has concluded that the level of cadmium reported in 

samples of locally grown pigeon peas would not contribute excess dietary cadmium to preschool 

children who eat no more than 5 of the largest (6 ounces) servings per week of locally grown pigeon 

peas. Adults who eat the largest serving sizes (12 ounces) should limit intake to 11 servings per week. 

Typical serving sizes for preschool children (1.5 ounces) do not contribute excess cadmium below 20 

meals per week and adults who eat a typical serving (3 ounces) may eat up to 44 meals per week 

without exceeding recommended cadmium intake levels. Exceeding recommended levels of 

cadmium in the diet would not typically result in immediate health consequences. Excessive 

cadmium intake over decades, however, could contribute to harmful levels of cadmium 

accumulation in the kidneys, possibly resulting in kidney disease. 

To be protective, these exposure estimates assumed that people consistently ate the largest 

portions typically consumed at a meal, and that the pigeon peas contained the highest level of 

cadmium measured. These assumptions, however, likely overestimate the extent of exposure for 

the majority of the population. 

Whether the limited sampling results are representative of cadmium concentrations in other locally 

grown pigeon peas is unclear; but the significant uncertainty in the evaluation stresses the need to 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 110

conduct further sampling. Preliminary evaluation results and the totality of the available data 

suggest a potential for uptake of metals from soil into food crops—thus further investigation is 

warranted. To evaluate better this exposure pathway, ATSDR has recommended a collaborative 

effort to conduct additional sampling of locally grown foods.

5.1. Introduction 

Many Viequenses remain concerned that past military training activities in the eastern portion of their 

island left elevated levels of heavy metals in the surface soil. Plants could take up these metals. And 

when people eat those plants, they could be exposed. Viequenses also question whether animals could 

accumulate heavy metals if they forage in areas where past military activities occurred, and whether this 

could result in exposure for people who consume meat and milk products from these animals. 

Viequenses depend on many local animal and vegetable products as food sources and for economic 

support. Thus, for Viequenses the safety of locally produced foods has both health and economic 

implications.

5.2. Assessment of Available Data 

Since 2000, a number of independent studies have explored levels of heavy metals in Vieques 

vegetation and livestock. This section provides a brief summary of the results and discusses their 

strengths and limitations, together with ATSDR’s evaluation and response to the findings. 

The studies discussed in this section were prepared by scientists associated with the University of Puerto 

Rico and Casa Pueblo, a local community advocacy organization. Several of these studies were 

presented and discussed by the authors during the November 2009 meeting in Atlanta, GA. 

5.2.1. Studies from 2000–2002

 In 2000, researchers from Casa Pueblo and the University of Puerto Rico sampled the prevailing 

vegetation in the Live Impact Area (LIA) (specifically Carrucho Beach, Monte David, and Gato and 

Icacos Lagoons) for heavy metals (Massol Deyá and Díaz 2000). Reference populations of the 

same species were also collected in Bosque Seco de Guánica and RUM Alzamora Ranch. The 

plants collected included Urochloa maxima (root and stem), Sporobolus virginicus (root and 

stem), Syringodium filiform (stem), Ipomoea violaceae (fruit), Faidherbia albida (stem), 

Calotropis procera (leaves), among other species. The authors reported that the concentrations 

of heavy metals such as lead, cobalt, and manganese in Vieques vegetation were significantly 

higher than concentrations detected in the reference locations. 

 In 2001, the same researchers randomly collected agricultural and common vegetation from 

three sites within the residential section of Vieques: an agricultural area in Monte Carmelo, 

another area of Monte Carmelo that bordered the former Camp Garcia, and an agricultural farm 

in Barrio Monte Santo, Gobeo sector (Massol Deyá and Díaz 2001). In this paper, discussion was 

limited to the two farms sampled in the civilian area of Vieques and focused on plants grown for 

an agricultural economy. Sampling included leaves and stems of pumpkin, pepper, pigeon peas, 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 111

pineapple, and yucca. The study reported that the concentration of cadmium, cobalt, copper, 

lead, and manganese exceeded levels reported in typical vegetation in temperate zones (from 

Smith and Huyck 1999). The authors stated that roots, stems and leaf samples of pumpkin, 

pepper, pigeon pea, pineapple and yucca had elevated lead and cadmium concentrations while 

guamá and mango trees did not show any elevated metals concentrations. On August 18, 2001, 

the researchers from Casa Pueblo collected hair samples from goats that grazed in Mount 

Santos and Santa María on Vieques (Massol Deyá 2002). As a reference, samples were collected 

from goats that pastured in the main island of Puerto Rico. The publication reported that hair 

from goats grazing in Vieques contained higher levels of lead than did goats on the main island. 

No mercury was detected in the goat hair (detection limit was 0.03 μg/g). 

Because of these results and other studies by the same researchers reporting elevated levels of heavy 

metals in plants and livestock, on August 7, 2001, the Puerto Rico Department of Agriculture (PRDA) 

placed an embargo on Vieques produce and livestock. The Puerto Rico Department of Agriculture, in 

cooperation with the Farmers Association of Puerto Rico, sampled grass, fruit-bearing trees, and bovine 

livestock from Monte Carmelo, Martineau, Monte Santo, Esperanza, Lujan, Gubeo, and western Vieques 

for cadmium, cobalt, copper, lead, manganese, and nickel. The Department of Agriculture and the 

Farmer’s Association concluded that the agricultural products from Vieques were suitable for 

consumption and did not contain toxic levels of these metals (PRDA 2001). When the Department of 

Agriculture and the Farmer’s Association could not duplicate the Massol Deyá and Díaz’ studies, the 

embargo was lifted (El Nuevo Día 2001).

5.2.1.1. ATSDR Evaluation

During preparation of the public health assessment evaluating soil exposure (ATSDR 2003), ATSDR cited 

two of the studies (Massol Deyá and Díaz 2000, 2001). These studies reported elevated metals in local 

vegetation and agricultural areas. This issue was originally addressed as a community concern in the Soil 

Pathway Evaluation Public Health Assessment (ATSDR 2003).

ATSDR requested that an agronomist with the U.S. Department of Agriculture independently review the 

2000 and 2001 Massol Deyá and Díaz studies. The agronomist determined (USDA 2002) that although 

the studies provided evidence that heavy metals were accumulating in plants, the study’s limitations 

prevented estimation of a human exposure dose:

1. Humans do not eat many of the species sampled in this study. When edible species were 

sampled, the edible portions were not. Human exposures from locally grown foods are best 

estimated from the edible portions of the food source. In general, the edible portions of plants 

are less likely to accumulate metals from soil because of normal plant processes (e.g., 

physiological barriers that prevent contaminants from getting to the tops of plants) (ATSDR 

2001).

2. The study lacked the use of standard reference materials to demonstrate that the results were 

accurate. It also lacked background corrections for lead, cobalt, nickel, and cadmium to 

eliminate the effect of light scattering by any nonelement materials in the samples, which can 

result in a concentration overestimate.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 112

3. The metals analysis did not indicate whether the metals were in a bioavailable form (i.e., in a 

chemical form readily absorbed into plant tissues from the surrounding environment). This is 

important because vegetation samples include both contaminants taken up by the plant and soil 

particles from the surrounding environment. Even with a thorough washing, small soil particles 

will adhere to the plant materials and can actually carry more contaminants than those taken up 

by the plant from the soil (ATSDR 2001). The researchers did not determine how much of the 

chemical was adhered externally as soil and how much was in the plant tissue. 

Because of these limiting factors, ATSDR could neither quantify human exposures appropriately nor 

draw any valid health conclusions about whether consuming Vieques plants would result in harmful 

health effects. ATSDR has recommended additional sampling of locally grown produce that would 

improve the evaluation of this exposure pathway. Details of ATSDR’s recommendations are at the end of 

this chapter and in Chapter 9 of this report.

ATSDR was unable to evaluate human exposure to goat meat and milk products from the sampling data 

presented in Massol Deyá (2002). Information was missing on similarities and differences between the 

goats in Vieques and the reference population (e.g., goat species, age, whether differences were 

statistically significant) and how they might affect interpretation of the hair sampling results. The report 

was unclear regarding how the hair samples were prepared for analysis. Inadequate processing of the 

hair for chemical analysis can lead to misleading results and to difficulty in interpreting whether the data 

represent contamination internal to the hair shaft or incomplete removal of any external contamination. 

Additionally, limitations in interpreting the health significance of hair sampling data precluded ATSDR 

from using the goat hair data reported in Massol Deyá (2002). Three key limitations of hair analysis 

generally prevented further characterization of exposures:

1. Hair analysis results cannot pinpoint the sources of detected chemical contaminants. For 

instance, hair analysis results typically cannot distinguish substances deposited onto hair (e.g., 

dusts) from substances that might have distributed into hair following an environmental 

exposure, such as ingestion of contaminated drinking water or food. In other words, hair 

analysis generally cannot differentiate internal from external exposure.

2. Currently, the scientific community does not know the range of contamination levels typically 

found in hair. Without reliable data in the peer-reviewed literature on baseline or background 

hair contamination levels in the general population, and without hair samples collected from 

comparison populations, health agencies cannot determine whether hair analysis results from a 

given site are unusually high or low. In Massol Deyá (2002) a comparison population of goats 

was sampled, and the results supported the author’s conclusion that the goats sampled on 

Vieques had higher concentrations of heavy metals in hair relative to the comparison 

population. 

3. A critical input into public health assessments is an understanding of the dose—whether 

measured or estimated. Because we currently know so little about rates at which substances in 

human and animal bodies distribute into hair, calculation was not possible of internal doses 

from hair sampling results. Hair analysis, then, would provide no added insight into estimating 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 113

exposures to humans, but it does imply a need to sample directly meat and milk from these 

animals to determine whether the meat and milk are safe for consumption.

For most substances, insufficient data are currently available to support any prediction of adverse health 

effects from concentrations in hair. Detection of a substance in a hair sample generally will not tell how, 

when, or where exposure to that substance occurred. Data from plant and animal foods that people 

actually consume are best suited for determinations about the possible health implications for people 

who eat those foods. Accordingly, as part of its evaluation, ATSDR recommends additional sampling of 

local produce and livestock.

5.2.2. Studies from 2003

In 2003, researchers from University of Puerto Rico published a study discussing the same data the 

authors published in April 10, 2000—plant samples collected in February and March 2000 and analyzed 

for heavy metals (Díaz and Massol Deyá 2003). This paper compared concentrations found on Vieques 

with concentrations detected on the main island of Puerto Rico. The 2000 sampling included plant stems 

and leaves but did not include the edible portions of the plants sampled. This peer-reviewed publication 

provided more information on sampling, preparation, and analytical techniques than did the April 2000 

report. In addition to the 2000 sampling data, this paper included new samples of C. cajan (pigeon peas) 

leaves and fruit taken August 18, 2001. It also discussed the ratio of contamination detected in the fruit 

to contamination in the leaves. The study compared concentrations detected in pigeon pea fruit and leaf 

samples collected August 18, 2001. For some metals, higher concentrations were found in the fruit (zinc, 

nickel, cadmium and cobalt). For other metals, higher concentrations were found in the leaves (copper 

and lead).

5.2.2.1. ATSDR Evaluation

In May 2009 ATSDR obtained a copy of the 2003 Díaz and Massol Deyá study. As part of its evaluation of 

Vieques, ATSDR reviewed the pigeon pea data in this study. The data reported in Díaz and Massol Deyá 

have significant limitations that restrict ATSDR’s ability to interpret the study findings’ significance. 

These limitations include no mention of comparison samples and no indication of statistical significance 

in the data reporting pigeon-pea metal concentrations. The sampling results from only one study are not 

representative of the extent of cadmium in local produce and do not represent the potential for 

cadmium exposure to the general population from consuming locally grown pigeon peas. 

A preliminary evaluation concluded that the level of cadmium reported in a few samples of locally

grown pigeon peas would not contribute excess dietary cadmium to preschool children who eat no 

more than 5 of the largest (6 ounces) servings per week of locally grown pigeon peas. Adults who eat 

the largest serving sizes (12 ounces) should limit intake to 11 servings per week. 

To be protective, these exposure estimates assumed that people consistently ate the largest portions 

typically consumed at a meal, and that the pigeon peas contained the highest level of cadmium 

measured. These assumptions likely overestimate the extent of exposure for the majority of the 

population. Typical serving sizes for preschool children (1.5 ounces) do not contribute excess cadmium 

below 20 meals per week. Adults who eat a typical serving (3 ounces) may eat up to 44 meals per week 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 114

without exceeding recommended cadmium intake levels. Still, excessive cadmium intake over decades 

could contribute to harmful levels of cadmium accumulation in the kidneys, possibly resulting in kidney 

disease. Table 5-1 provides details on the methodology used in this evaluation. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 115

Table 5-1. Exposure dose for pigeon pea fruit (Díaz and Massol Deyá 2003 data)

Percentile C 

mg/kg

IR 

kg/day

Portion 

size in Oz

Meals 

per 

week

Meals 

per 

Year

EF 

days/yr

ED 

Yrs

BW 

kg

AT 

days

FA 

unit 

less

DOSE

(mg/kg/day)

Target 

dose

(mg/kg/da

y)

Chemical IR

cadmium 95th adult 3.17 0.10 12 5 260 260 64 70 23360 0.05 0.00016 0.00036

95th child 3.17 0.05 6 5 260 260 6 16 2190 0.05 0.00035

Number of weekly meals to reach tolerable daily intake level TDI

95th child 

<6 yr

3.17 0.05 6 5 260 0.00036 0.00036

50th child 

<6 yr

3.17 0.01 1.5 20 1040 0.00036

95th adult 3.17 0.10 12 11 572 0.00036

50th adult 3.17 0.02 3 44 2288 0.00036

Where

C Concentration (mg/kg) 

IR Ingestion rate in percentile (e.g. 95th means that 95% of the population has an intake level below that amount): see below

EF Exposure frequency or events: 260 days/year = 5 days/week for 52 weeks/year; 156 days/year = 3 days/week for 52 weeks/year

ED Exposure duration over which exposure occurs: 64 years (adult); 6 years (child)

AT Averaging time: period over which exposures are averaged (expressed in days) for noncancer AT=ED*365 days/year

FA Food absorption factor: Assumes dietary cadmium absorption of 5%. (ATSDR Cadmium Toxicological Profile, Sep 2008)

BW Body weight in kilograms

TDI Tolerable daily intake, 0.00036 mg/kg-bw/day, European Food Safety Authority (EFSA) 2009
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page | 116 

dry weight 

rate 

95th adult 98.7 g/day See EFH Chapter 9, Section 9.2.5 for conversion between as consumed and dry weight intake rates 

50th adult 24.8 g/day used 71.8 percent water content for "beans –dry–black-eyed peas (cowpeas)–cooked," see Table 9-27

95th child 1.6 g/kg/day 

50th child 0.4 g/kg/day 

USEPA. 1997. Exposure Factors Handbook. August 1997. Available from: http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=20563 

Tolerable daily intake

TWI= tolerable weekly intake 

2.5 ug/kg BW EFSA 2009 

0.00036 mg/kg/day Converted to daily intake 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page | 117 

5.2.3. Studies from 2004–2005 

 In 2004, researchers from the University of Puerto Rico’s Agricultural Extension Service in 

Vieques and the Land Authority of the Commonwealth of Puerto Rico collected a total of 72 

samples of smooth cayenne pineapple fruit, leaf tissues, and soil. They collected these samples 

from two pineapple plantations (one located in Barrio Luján in the civilian zone in Vieques and a 

control located in Barceloneta on the mainland of Puerto Rico). The samples were to determine 

the total concentration of arsenic, cadmium, chromium, cobalt, and lead in the fruit. The author 

concluded that no contamination was found in the pineapple fruit or leaf samples from either 

plantation. In all fruit samples arsenic, cadmium, cobalt, and lead either were below levels of 

detection or were not detected. No contamination was observed in the pineapples from Vieques 

when compared with those from the Barceloneta plantation (Lopez Morales 2005). Higher levels 

of metals were, however, found in the soil at the Barceloneta plantation, which the author 

attributed to the soil’s natural composition. The study concluded that the results were within 

accepted regulatory levels. 

 In 2005, Massol Deyá et al. published a paper discussing the same data that the authors 

published in April 10, 2000, and again in 2003—plant samples collected in February and March 

2000 and analyzed for heavy metals. The authors noted that “distinctive profiles are observed 

within the studied species thus reflecting differences in their physiological properties.” In 

addition to the 2000 sampling data, this paper included new samples of Syringodium filiforme

(Manatee grass) taken from the Atlantic Fleet Weapons Training Facilities (AFWTF) in 2004 and 

from Guánica State Forest in 2003 and 2004. Concentrations of heavy metals were higher at 

AFWTF. The authors proposed the hypothesis of bioaccumulation through the food chain: 

manatee grass to crustaceans, fish eat the crustaceans and then are eaten by people. A similar 

food-chain scenario was hypothesized for migratory birds (Massol-Deyá et al. 2005). 

5.2.3.1. ATSDR Evaluation 

The data in Massol-Deyá et al. (2005) might well provide ecologically important information, but they 

are not directly relevant to evaluating human health—manatee grass is not typically a Viequense food 

source. ATSDR has recommended additional produce sampling. 

The López Morales (2005) study was unique in that its purpose was specifically to sample the edible 

portion of a commonly consumed agricultural product grown in Vieques, smooth cayenne pineapples. As 

part of the evaluation of Vieques, ATSDR evaluated the level of chromium—the only metal detected—in 

the pineapple fruit samples. Using a standard intake rate for fruit consumption,23 ATDSR calculated the 

estimated exposure dose at below levels of concern for adverse health effects. 

López Morales (2005) cited two additional studies that found “no contamination in the civilian zones of 

Vieques”: 1) College of Agriculture & Environmental Science: Soil, Plant and Water Laboratory 

 

23 About 7 ounces of fruit a day (mean total fruit intake; USEPA 1997) 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 118

(September 6, 2001), and 2) A & L Southern Agricultural Laboratories, Inc. (August 31, 2001). Both 

studies analyzed for heavy metals in guinea grass, sugar apple, wild tamarind, mango, green banana 

fruit, pigeon peas, genip fruit, grapefruit, and buffet grass. These studies sampled species Viequenses 

regularly eat. ATSDR is attempting to obtain copies of these studies, but to date has not been successful.

5.2.4. Studies from 2008

In January 2008, leaves from cilantro, spinach, beans, peppers, and papaya plants were collected from a 

Viequense organic farm and analyzed for cadmium, chromium, copper and lead. The researchers 

believed the organic farm’s soil would be representative of naturally occurring soil plus any local, 

airborne contamination. The researchers found that concentrations of lead and cadmium in the 

Viequense vegetation were significantly higher than those detected in the Mayagűez reference plants

(Díaz de Osborn et al. 2008). Mayagűez is a town on the western end of Puerto Rico, approximately 120 

miles from Vieques

5.2.4.1. ATSDR Evaluation

In reviewing the Diaz de Osborn et al. (2008) report, ATSDR was initially concerned that the data 

appeared to indicate potential harm to humans consuming this produce. Due, however, to the report’s 

lack of any data quality assurance information, ATSDR questioned whether those data accurately 

represented typical heavy metal concentrations in locally grown produce. ATSDR consulted with the U.S. 

Department of Agriculture (USDA) about the study (R. Chaney, U.S. Department of Agriculture, 

Agricultural Research Station, Beltsville, MD, personal communication, 2008 Oct 28–30). USDA noted 

that the reported levels of copper would be phytotoxic to the plants. USDA commented that the 

reported measurements were consistent with plants grown in soils that had been changed to increase 

metal uptake in the plants (Sterrett 1996). As a result, how ATSDR should interpret these data is unclear. 

ATSDR has recommended additional sampling of locally grown produce to resolve uncertainties in the 

available data. Still, until additional data are available and this exposure pathway is more thoroughly 

evaluated, the USDA suggests following several simple methods for reducing metal uptake into garden 

produce from soil. More information is available at USDA’s National Agriculture Library Web site: 

http://www.nal.usda.gov/. Specialized gardening information is available online at: 

http://riley.nal.usda.gov/nal_display/index.php?info_center=8&tax_level=2&tax_subject=7&topic_id=1

063.

The conclusions and recommendations from ATSDR’s evaluation of local produce and livestock data 

follow in section 5.3 of this chapter and in Chapter 9 of this report. 

5.3. Conclusions and Recommendations

5.3.1. Conclusions

1. The overall data are insufficient to quantify adequately human exposures or draw any valid 

health conclusions about whether consuming locally grown produce and livestock would result 

in harmful health effects. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 119

2. Limited sampling data are available for pigeon peas, a staple food among Viequenses.

Interpretation of these data is uncertain because of the lack of adequate QA/QC information for 

the analytical findings.

A preliminary data evaluation completed for this report has concluded that the level of 

cadmium reported in a few samples of locally grown pigeon peas would not contribute 

excess dietary cadmium to preschool children who eat less than 5 of the largest (6 ounces) 

servings per week of locally grown pigeon peas. Adults who eat the largest serving sizes (12 

ounces) should limit intake to 11 servings per week.

Typical serving sizes for preschool children (1.5 ounces) do not contribute excess cadmium 

below 20 meals per week and adults who eat a typical serving (3 ounces) may eat up to 44

meals per week without exceeding recommended cadmium intake levels. 

Exceeding recommended levels of cadmium in the diet would not typically result in 

immediate health harm. Excessive intake of cadmium over decades could contribute to 

harmful levels of cadmium accumulation in the kidneys, possibly resulting in kidney disease. 

Typically, only a very small fraction (5%) of cadmium in food is absorbed in the body, 

especially in individuals with healthy diets containing adequate amounts of essential 

minerals such as zinc, iron and calcium (Reeves and Chaney 2008). 

3. Whether the limited sampling results are representative of cadmium concentrations in other 

locally grown pigeon peas is unclear; but the significant uncertainty in the evaluation stresses 

the need to conduct further sampling. 

4. Preliminary evaluation results and the totality of the available data suggest a potential for 

uptake of metals from soil into food crops—thus further investigation is warranted. To evaluate

better this exposure pathway, ATSDR has recommended a collaborative effort to conduct 

additional sampling of locally grown foods.

5.3.2. Recommendations

ATSDR supports additional sampling and collaborative data collection to evaluate more thoroughly this 

human exposure pathway. The following recommendations are intended to promote collection of high 

quality data of maximum utility, and to minimize data uncertainties: 

1. Sampling data should represent edible portions of a cross-section of local produce from local 

farms, home gardens, and local markets. Sample produce that tends to accumulate heavy 

metals more easily (e.g., leafy vegetables such as lettuce and spinach) rather than leaves of 

grain or fruit crops.

2. Survey residents to identify the prevalence and type of locally grown and commonly consumed 

garden produce. Sampling plan design should include produce types identified from this survey. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 120

3. Collect representative surface soil samples at the same location and time that garden and farm 

produce samples are taken. Soil samples should be of appropriate depth to represent the root 

zone. 

4. Collect samples of meat and milk products from Vieques forage-consuming livestock.

5. To avoid false high or low values, sample collection and analysis should conform to high 

standards of data quality, including detailed quality assurance/quality control information, 

standard reference materials for analysis, and background correction. Design the sampling plan 

to collect a sufficient number of samples to ensure high statistical confidence.

6. Collect samples from an appropriate background or control location for comparison with food 

samples produced on Vieques.

7. To facilitate exposure assessment, report data as consumed (wet weight).

8. Plan and conduct sampling protocols in collaboration with local scientists. One way to avoid 

misunderstandings about the data is for local scientists and an independent expert jointly collect 

and split several samples and provide analytical reports with QA/QC supporting information. A 

QA/QC standard could be split at the time the samples are collected.

9. Request technical assistance from the U.S. Food and Drug Administration (FDA) or the U.S. 

Department of Agriculture (USDA) in sample collection and analytical protocols. The USDA 

Agriculture Research Service has offered to provide, if requested, technical assistance in 

sampling plan design, collection, and analysis with proper QA/QC protocols.

5.4. References

Agency for Toxic Substances and Disease Registry. 2001. Summary report for the ATSDR expert panel 

meeting on tribal exposures to environmental contaminants in plants. Atlanta: Division of Health 

Assessment and Consultation; 23 March.

Agency for Toxic Substances and Disease Registry. 2003. Public Health Assessment, Isla de Vieques 

Bombing Range, Vieques, Puerto Rico. Atlanta: US Department of Health and Human Services, Public 

Health Service; 7 February.

Díaz de Osborne E, Acevedo-Acevedo P, Massol Deyá A. 2008. Evaluation of heavy metals in agricultural 

products of a farm with organic practices in the Bo. Lujan Sector Destination of Vieques (Puerto Rico). 

Casa Pueblo de Adjuntas, PR: University of Puerto Rico Biology Department.

Díaz E and Massol Deyá A. 2003. Trace element composition in forage samples from a military target 

range, three agricultural areas, and one natural area in Puerto Rico. Caribbean Journal of Science 

39;2:215–20.

El Nuevo Día. 2001. They declare suitable the agricultural products in Vieques; 13 December.

López Morales JL. 2005. Determination of arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co) and 

lead (Pb) in “smooth cayenne” pineapple fruit, leaves tissue and soil using inductively coupled plasmaoptical emission spectrometry (ICP-OES). Mayagüez, PR: University of Puerto Rico. Available at: 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 121

http://www.conucopr.org/ViewRecord.do;jsessionid=9352FA03CF29511445F3F457499BD7F1?id=11161

028 [accessed 2011 June 28].

Massol Deyá A and Díaz E. 2000. Heavy metals in the impact area prevailing vegetation, Vieques, Puerto 

Rico. Casa Pueblo de Adjuntas, PR: University of Puerto Rico, Recinto Universitario Mayagüez, Biology 

Department; 10 April.

Massol Deyá A and Díaz E. 2001. Toxic metals in the vegetation of the civilian zone of Vieques, Puerto 

Rico. Casa Pueblo de Adjuntas, PR: University of Puerto Rico, Recinto Universitario Mayagüez, Biology 

Department; 10 January.

Massol Deyá A. 2002. Herbivorous: additional evidence of heavy metal mobilization through the food 

web. In: Ciencia y Ecología: Vieques en Crisis Ambiental, Third edition. Casa Pueblo de Adjuntas, PR. 

Massol-Deyá A, Pérez D, Pérez E, Berrios M, Díaz E. 2005. Trace elements analysis in forage samples 

from a U.S. Navy bombing range (Vieques, Puerto Rico). Int J Environ Res Public Health 2(2):263–66.

Puerto Rico Department of Agriculture. 2001. Letter from Luis Colón to the Undersecretary of 

Agriculture concerning heavy metal tests on Vieques bovine livestock; 17 October.

Reeves and Chaney. 2008. Bioavailability as an issue in risk assessment and management of food 

cadmium: A review. Science Total Environ 398:13–19.

Reeves and Chaney. 2008. Bioavailability as an issue in risk assessment and management of food 

cadmium: A review. Science Total Environ 398: 13-19.

Sterrett SB, et al. 1996. Influence of fertilizer and sludge compost on yield and heavy metal 

accumulation by lettuce grown in urban soils. Environ Geochem Health 18:135-42.

US Department of Agriculture. 2002. March 5th letter from Rufus Chaney (USDA) to Jeff Kellam (ATSDR) 

concerning expert review of two vegetation sampling studies by Massol-Deya and Diaz.

US Environmental Protection Agency. 1997. Exposure factors handbook (Final Report). EPA/600/P95/002F a-c, 1997; Aug. Available online at: 

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=20563 [accessed 2010 Jan 28]

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 123

6. Air Pathway

6.1. Introduction to Air Pathway ................................................................................................... 124

6.2. Assessment of Available Data................................................................................................. 124

6.2.1. Assessment of Air Exposures in the Public Health Assessment .................................. 124

6.2.2. Review of the Air Modeling Process Used in the Air PHA ........................................... 126

6.2.3. Post-PHA Air Monitoring and Air Modeling Studies.................................................... 128

6.3. Findings................................................................................................................................... 131

6.4. Conclusions and Recommendations....................................................................................... 133

6.4.1. Conclusions.................................................................................................................. 133

6.4.2. Recommendations....................................................................................................... 134

6.5. References.............................................................................................................................. 134

Chapter 6 Summary

This chapter reviews how potential airborne exposures to contaminants from military operations at 

the former Vieques Naval Training Facility might have affected Viequense residential areas. 

Although our review draws primarily from sources used in the 2003 ATSDR Air PHA, we also 

summarize air monitoring data and air dispersion studies developed or collected after publication of 

the 2003 Air PHA. These later data assessed effects of ongoing or proposed open detonation or open 

burning and included site-specific meteorological data collected after 2003. 

We further evaluate the modeling process used in the 2003 Air PHA, the assumptions and data used 

in that modeling process, and compare the results with monitored data collected during recent 

open burning events. While this review finds the Air PHA modeling process consistent with 

established practices, it does identify two minor errors in estimating detonation source 

concentrations. These errors, however, do not affect the results or conclusions of the Air PHA.

Collectively, the available sampled and modeled data are adequate for the determination of any 

potential public health hazard arising from exposure to airborne contamination. By overestimating 

numerous aspects of the contaminant emissions and by assessing exposures for worst-case 

conditions, the 2003 ATSDR air dispersion model adequately addressed uncertainties inherent in the 

air dispersion modeling process. 

The model results indicate that in the residential areas of Vieques, airborne contaminants from 

historic military exercises on the Vieques Naval Training Range would have been essentially 

nondetectable and unlikely to have resulted in harmful effects. These results are supported by post 

2003 air monitoring studies conducted in support of the ongoing site remediation.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 124

6.1. Introduction to Air Pathway

In 1980, not long after ATSDR’s inception, Viequenses began to ask the agency whether the island’s air 

was safe to breathe. The residents were and are concerned about contaminants released to the air 

during the Navy’s military training exercises. These exercises included the Navy’s past use of explosive 

ordnance (early 1970s to April 1999), as well as exercises using inert ordnance (May 2000 to May 

2003).24 Among other concerns, Viequenses questioned whether toxic dusts from the explosiveordnance range could have blown into their neighborhoods.

During the time the Navy still conducted explosive-ordnance exercises on Vieques, three air-sampling 

studies occurred (1972, 1978, and 1979). Direct references for these studies are not available, but other 

documents reported and summarized the results (TAMS 1979; Cruz Pérez 2000). Appendix C of the Air 

PHA (ATSDR 2003) includes a review of the studies’ data, the availability of that data, and each dataset’s 

limitations. The Puerto Rico Environmental Quality Board conducted two of these studies, and the Navy 

conducted the other. None of the studies’ measurements detected air pollution at levels of health 

concern. Those conclusions are limited by the small number of air sampling locations and the small 

number of measured analytes. And because those historic sampling studies did not employ data quality 

control procedures that are accepted today, the studies could not conclusively determine by current 

standards whether airborne contaminants were present in Viequense residential areas. 

Thus ATSDR could not base health conclusions on these studies alone. Modeling, however, could 

provide another dataset that might clarify earlier findings.

When ATSDR first began evaluating the air pathway, two dispersion-modeling studies were available 

that produced distinctly different conclusions about potential exposures to particulate matter on 

Vieques. One was prepared by Navy contractors (IT 2000) and a second by Dr. Cruz-Pérez, a local 

professional engineer (Cruz Pérez 2000). As part of the 2003 PHA process, ATSDR hired three 

independent air modeling experts to review the studies. Appendix D of the Air PHA includes a summary 

and review of each of the modeling studies. After receiving feedback from the external reviewers, 

ATSDR decided to conduct an additional, independent modeling study using recommendations from the 

peer reviewers. Note that given the limited extent of air sampling that occurred at Vieques while the 

Navy used explosive ordnance, modeling was necessary. Appendix D in the Air PHA contains model 

documentation, including defining assumptions and results.

6.2. Assessment of Available Data

6.2.1. Assessment of Air Exposures in the Public Health Assessment

To estimate effects of explosive ordnance on air quality, ATSDR used a modeling analysis that evaluated 

86 different contaminants known to be released to the air when ordnance explodes (49 organic 

compounds, 29 metals, 5 explosive compounds, plus chaff, depleted uranium, and particulate matter 

 

24 The Air Public Health Assessment includes a more complete summary of the Former Vieques Naval Training 

Facility operational history.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 125

such as PM10). The model results found that as dust and smoke traveled from the explosive-ordnance 

range toward areas where people lived, chemicals released to the air by explosions dispersed to 

extremely low levels. For most contaminants, the predicted air quality effects at residential areas were 

so low that even if highly sensitive air sampling devices were in place they likely could not measure such 

low levels of the contaminants. 

For example, particulate-matter contaminants emitted during explosive ordnance exercises were 

predicted to account for less than 1 percent of the particulate-matter25 concentrations measured in 

Viequense residential areas. 

This comparison suggests that LIA emissions had a small effect on residential air quality. Using this 

modeling analysis and the previously referenced air sampling data, ATSDR concluded that of the 86 

contaminants evaluated that might have been part of emissions from the former Vieques Naval Training 

Range, by the time they reached the residential areas of Vieques none exceeded any health comparison 

values. In other words, even the total effect of the chemicals combined did not result in residential air 

pollution.

From May 2000 through May 2003, the Navy conducted military training exercises with inert

(nonexplosive) ordnance. During 2000–2001, the Puerto Rico Environmental Quality Board conducted 

ambient air monitoring at two stations in Viequense residential areas. On days when such inert 

ordnance fell on the explosive-ordnance range, the Puerto Rico Environmental Quality Board collected 

more than 50 particulate-matter samples in the residential areas of Vieques. These data and supporting 

information are reported in the U.S.EPA Air Quality System (AQS)—formerly the Aerometric Information 

Retrieval System (AIRS)—and summarized in the Air PHA (Appendix C). In every sample, the levels of 

particulate matter were much lower than health-effects levels. In fact, no clear relationship was ever 

established between the quantity of inert ordnance dropped in the LIA and the levels of air pollution 

measured in the island’s residential areas. These observations on estimated contaminant air 

concentrations led ATSDR to conclude that on days when inert ordnance fell into the LIA, levels of air 

pollution did not pose a health hazard to the island’s residents.

In addition to the modeling study and the analysis of historic air monitoring data, ATSDR conducted onsite air monitoring during the June 2001 Navy air-to-ground, inert ordnance exercises. The results of this 

sampling effort are documented (ERG 2001), and the Air PHA describes their limitations. Due to station 

location/siting problems (as discussed in the Air PHA), the sampling data do not meet applicable quality 

control standards. The measured contaminant concentrations are nonetheless consistent with the 

public health conclusions.

 

25 The term “particulate matter” refers to solid particles and liquid droplets in the air. PM10 and PM2.5 refer to 

particulate matter having aerodynamic diameters less than or equal to 10 and 2.5 microns, respectively. Also note 

that while current emphasis on the health effects of particulate matter focus on PM2.5, past health-based 

standards used PM10. The 2003 Air PHA used PM10 to make direct comparisons with earlier measurements and 

model results.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 126

The following Air PHA conclusions are based largely on ATSDR’s modeling effort and on data from air 

monitoring stations at Isabel Segunda and Esperanza established and maintained by the Puerto Rico 

Environmental Quality Board:

The Navy’s ordnance exercises at the LIA did not pose a health hazard in the residential areas of 

Vieques.

Wind-blown dust from the explosive-ordnance range did not and does not pose a health hazard 

to residents. 

The Air PHA also contains a thorough review of the then-available modeling studies, the ATSDR 

modeling study, and other reported air monitoring datasets.

6.2.2. Review of the Air Modeling Process Used in the Air PHA

Eastern Research Group (ERG) and Trinity Consultants conducted the ATSDR air modeling study to 

evaluate potential air exposures from historic operations at the former Vieques Naval Training Range. 

The Air PHA and a follow-up report (Wilhemi et al. 2006) describe the specific procedures, assumptions, 

and results of the modeling effort. Trinity Consultants conducted the “Calpuff” dispersion modeling and 

submitted the results to ERG (Trinity Consultants 2002).

Direct measurement of airborne emissions produced by military ordnance explosions is not possible.

26

Quantitative modeling, however, is a useful approach for assessing potential emissions produced by 

explosive ordnance events. To evaluate potential exposures to airborne contamination, the Air PHA 

used the following modeling procedure:

1. Make health-protective estimates of airborne emission concentrations from individual ordnance 

items using the Combined Obscuration Model for Battlefield Induced Contaminants (Army 

Research Laboratory 2000); 

2. Use a U.S.EPA-accepted air dispersion model (Calpuff) to estimate event-specific, healthprotective, 24-hour and annual contaminant concentrations at points of maximum off-site 

exposure;

3. Calculate maximum daily and annual contaminant concentrations at off-site exposure points 

using documented ordnance usage data to scale up the event-specific, dispersed-contaminant 

concentrations; and

4. Evaluate the potential public health effects of exposure to those contaminants by comparing the 

estimated maximum 24-hour and annual contaminant concentrations with appropriate health 

comparison values.

 

26 The blasts would destroy the monitoring equipment; indirect downwind sampling is possible, however.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 127

This review finds that the overall rationale for that approach is sound, and each of the assumptions 

underlying the selection of model parameters is well documented in the Air PHA and in the literature 

(text and Appendix D; Wilhemi et al. 2006). The modeling procedure was developed from comments and 

recommendations by external, independent reviewers who assessed the existing studies. 

A number of factors or model assumptions within the 2003 study collectively led to an intentional 

overestimation of potential exposures, thus helping to ensure the conclusions are health-protective:

 Overestimate particulate emission rates from explosions by assuming all particulates are 

composed of the PM10 fraction (larger particles not susceptible to significant air dispersion are 

included as PM10). 

 Overestimate emission rates of explosives (e.g., TNT, RDX, HMX, aluminum powder) by 

assuming 10% of explosives are not consumed in the explosion and are available for dispersion. 

By contrast, available data show that less than 1% of explosives remain after detonation.

 Because of variations in explosive composition of different ordnance types, maximum 

composition percentages of TNT, RDX, and aluminum powder were assumed to comprise 

collectively more than 125 percent of total explosive use.

 The emission estimates also assumed that all ordnance dropped, fired, or launched into the LIA 

exploded, and that all emissions emanated from a single-source location. Thus bombs exploding 

in multiple locations would spread the emissions over a relatively large area, leading to greater 

dispersion and lower concentration at any single downwind site.

 Potential exposure evaluations are all based on worst-case meteorological conditions for both 

24-hour and annual exposures for a person living directly on the site boundary (i.e., the location 

of highest off-site concentration estimates). Residential areas are at least 3 miles farther west 

which, for off-site residents, would result in commensurately lower exposure doses.

Three EXCEL spreadsheets developed by ERG (METALS.xls, ORGANICS.xls, and EXPLOSIVES.xls) contain 

the modeling study’s specific results. These spreadsheets were transmitted to ATSDR via e-mail (John 

Wilhelmi, ERG, to Mark Evans, ATSDR, personal communication, 2009 Dec 3). A review of the 

spreadsheets has revealed two minor errors or discrepancies.

First, metals concentrations within the particulate plume are calculated by adding metals in the 

explosive compounds, metals in the ordnance casing, and metals in the soil ejected into the air by the 

explosion. Concentrations of explosives (e.g., TNT, RDX, and HMX) present in Live Impact Area soils are 

not similarly accounted for in assessing plume concentrations of those materials. Still, because the 

concentrations of explosives compounds of LIA soils are so low, the relative contribution from soil ejecta 

is insignificant. 

As an example, the concentration of TNT in LIA soil averages 2.9 parts per million (ppm). Maximum 

annual emissions of TNT as soil ejecta (based on the TNT soil concentration of 2.9 ppm) would be 

approximately 1.6 pounds per year (or 0.00027 pounds per hour; based on 5,840 hours per year 

operations). In comparison, the ATSDR air dispersion model assumes that airborne emissions from 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 128

undetonated TNT in bombs (assuming 10% of TNT does not ignite) is 10.76 pounds per hour. If only 5% 

of TNT remains after the explosion, this hourly TNT emission rate becomes 5.38 pounds per hour. 

Considering that available studies show less than 1% of TNT does not ignite, the amount of TNT in the air 

is overestimated and, relative to the overestimate from TNT ignition, the contribution from TNT in soil 

ejecta is very small.

The second discrepancy detected in the ERG spreadsheets concerns calculation of maximum 24-hour 

emission rates of metals in air particulates. This calculation neglected to include a conversion factor for 

adjusting emission rates in pounds per hour to emissions in grams per second. Considering that an 

emission rate of 1 pound per hour is about 8 times greater than an emission rate of 1 gram per second, 

the use of an input value 8 times too large results in an eightfold overestimate of the maximum 24-hour 

emission rate. Collectively, however, the discrepancies in the air dispersion modeling process do not 

significantly affect the results or conclusions expressed in the 2003 Air PHA.

The Air PHA’s Appendix E contains 39 comments on the modeling process and the PHA conclusions, and 

ATSDR’s responses to those comments. We reviewed those comments and responses to ensure that 

each response adequately addressed each concern. This review finds that the responses were 

appropriate and provided adequate support for the Air PHA assessment procedure and the resultant 

public health conclusions.

We note, however, one specific concern and the response thereto (Air PHA, comment/response #8, 

Appendix E). The stated concern was “No data is (sic) available related to PM2.5 . . .” The response 

indicates that in fact PM2.5 was not explicitly modeled. But it is addressed by making the most health 

protective assumption possible (i.e., that the estimated PM10 concentrations consisted entirely of 

PM2.5 particulates). Thus the annual average and maximum 24-hour concentration increases caused by 

explosive ordnance events (0.04 μg/m3for annual average; 10.2 μg/m

3

for 24 hour average) would still 

be (from the 2003 Air PHA):

” . . . considerably lower than EPA’s current (PM2.5) health-based standards (15 

μg/m3 for annual average, and 65 μg/m3for 24 hour average concentrations). 

Therefore, the modeling data indicate that air emissions of particulate matter, 

whether coarse or fine, from the military training exercises were not at levels of 

health concern for the residential areas of Vieques.”

6.2.3. Post-PHA Air Monitoring and Air Modeling Studies

After the Air PHA’s release, the Navy conducted additional air monitoring and modeling related to the 

“Time Critical Removal Actions” for the blow-in-place (BIP) munitions detonations. That is, for the 

removal of dropped, launched, or fired unexploded ordnance and for a planned effort to burn 

vegetation from the live-ordnance training areas. These efforts were designed to allow safe access to 

historic live fire areas, and were documented in a series of reports:

1. Air Dispersion Modeling of the TCRA/BIP Activities on the Former Vieques Naval Training Range, 

Draft (US Navy Contract Task Order 0047, February 2007; prepared by CH2MHill, Herndon, VA).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 129

2. Air Dispersion Modeling for TCRA-Prescribed Vegetation Burns on the Former Vieques Naval 

Training Range, Draft Final (US Navy Contract Task Order 0047, June 2008; prepared by 

CH2MHill, Herndon, VA).

3. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training Range: August 

2005 through December 2006, Draft (US Navy Contract Task Order 0047, February 2007, 

prepared by CH2MHill, Herndon, VA).

4. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training Range: January 

1, 2007 through March 31, 2007, Draft (US Navy Contract Task Order 0047, June 2007, prepared 

by CH2MHill, Herndon, VA).

5. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training Range: April 1, 

2007 through June 30, 2007, Draft (US Navy Contract Task Order 0047, January 2008, prepared 

by CH2MHill, Herndon, VA).

6. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training Range: January 

1, 2008 through June 30, 2008, Draft (US Navy Contract Task Order 0047, February 2009, 

prepared by CH2MHill, Herndon, VA).

The air monitoring data summaries describe real-time, on-site (downwind) sampling events conducted 

before, during, and after 51 in-place ordnance detonation events at the LIA. The information in these 

reports shows that the monitoring analyses were conducted using accepted methods, and that the 

results were within acceptable limits for sampling and analytical quality assurance.

Analytes measured were PM10, metals, and explosives at hourly or 8-hour intervals. Measurements 

were summarized as 8-hour or 24-hour averages. No explosives or metals in any of the air samples have 

been reported in concentrations above regulatory or applicable health based standards. One detonation 

event might have ignited surrounding vegetation; it resulted in a 24-hour, PM 10 value of 153 μg/m3—

just above the NAAQS standard of 150 μg/m3. This measurement, however, was taken at an on-site 

location immediately downwind of the detonation site. None of the 51 detonation events produced 

elevated PM 10 measurements at stations closer to areas of potential off-site exposure. The exposure 

levels for metals are more than 10 times below the health guideline. Thus interaction effects between 

chemicals are not likely, and additive or synergistic effects between chemicals are not likely to enhance 

the mixture’s toxicity. In sum, harmful effects from the mixture of chemicals in air are not likely (ATSDR 

2004).

An air dispersion model conducted in support of the BIP detonations (CH2MHill 2007a) supports the 

measured monitoring results. This modeling study used a different air dispersion model (Open 

Burn/Open Detonation Dispersion Model; Bjorkland et al. 1998) and site-specific meteorological data 

unavailable when the Air PHA was conducted. The results of this air dispersion model also support the 

monitoring results and the conclusions of the ATSDR modeling study. Estimated airborne contaminant 

concentrations from BIP events at areas of potential off-site exposure “are below both regulatory 

standards and reasonable analytical detection limits for all compounds.”( CH2MHill 2007a).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 130

The air dispersion modeling of the BIP detonations (CH2MHill 2007a) used meteorological data collected 

from the Camp Garcia airfield on Vieques. These site-specific windspeed and direction data for the year 

2005 were not available when the ATSDR PHA was conducted. Instead, the ATSDR air dispersion model 

used then-available meteorological data from the Roosevelt Roads Naval Station and the San Juan 

Airport station. 

Figure 6-1 shows wind rose diagrams for Camp Garcia, the San Juan LM Airport, and the Roosevelt Roads 

stations (from CH2MHill 2007a). The Camp Garcia site is in a shallow topographic bowl on the south 

central portion of Vieques. The 2005 wind rose reflects this location with the predominant wind 

directions blowing from the northeast, while the San Juan LM Airport and Roosevelt Roads predominant 

wind directions are similar, but more southeasterly and easterly. Average annual wind speeds for the 

Roosevelt Roads and San Juan LM Airport stations are about two to four times greater than for the 

Camp Garcia station (2.88 and 4.10 vs. 1.46 m/sec, respectively). No long-term meteorological data are 

available for the LIA. The residential areas of Vieques are west of the LIA; the use of wind data that 

maximizes the easterly component of dispersion and uses a higher annual average wind speed provides 

a health-protective estimate of contaminant transport. That is, application of the Camp Garcia wind data 

would tend to disperse more contaminants a shorter distance and more toward the ocean (to the 

south), with lesser amounts to residential areas (to the east). 

In addition to the recent evaluation of BIP detonations, the Navy has proposed prescribed burning of LIA 

vegetation to access safely and to remove remaining unexploded ordnance. In support of this proposal, 

the Navy has conducted additional air modeling to assess the potential effects of such prescribed 

burning (CH2MHill 2008a). Although the Air PHA did not address vegetation burning, it did address past 

operations of open burning/open detonation (OBOD) of excess or recovered ordnance. As the mass of 

ordnance involved in past OBOD events was small relative to the mass involved in then-ongoing Naval 

operations, the 2003 Air PHA found that air emissions from past OBOD events did not present a public 

health hazard to Viequenses. 

The 2003 Air PHA included an assessment of the public health significance of exposure to dust from 

African storms based on measured or estimated PM10 concentrations and found that PM10 exposures 

attributed to such dust storms were not a public health hazard. At the time of publication of the Air PHA, 

there were no data available on the chemical-specific makeup of dust from these storms. A recent study 

by Gioda et.al. (2007) presented PM10 and metals concentrations from air samples for several Puerto 

Rican locations, including Vieques, which makes such chemical-specific data available. This study was 

able to correlate seasonal, measured air particulate concentrations at Vieques and other Puerto Rican 

locations with African dust storms. Most of the metals analyzed in these samples (cadmium, cobalt, 

copper, iron, nickel, lead, and vanadium) were well below their applicable health comparison values and 

do not represent a public health hazard. 

The annual average arsenic concentration of 0.0003 μg/m3 is just above the comparison value of 0.0002 

μg/m3, which is based on health protective exposure assumptions, a lifetime excess cancer risk of 

0.000001, and the U.S.EPA unit inhalation cancer risk of 4.3e-3 (per μg/m3). Using the Gioda et.al. (2007) 

data, the estimated lifetime excess cancer risk for inhalation exposure to arsenic on Vieques is 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 131

0.0003 μg/m3x 4.3e-3 per μg/m3= 0.0000013

The measured annual average arsenic air particulate concentration and resulting estimated lifetime 

excess cancer risk at Vieques is midway between other Puerto Rican values and not significantly 

different from the Fajardo, PR background location identified by Gioda et.al. (2007). Dust from African 

storms provides a measurable contribution to background particulate loadings at Vieques and other 

locations only during summer months and thus represents only a seasonal contribution to the 

predominantly local air particulate loads. Inhalation of specific metals from African dust storms, while 

contributing to seasonal particulate loads at Vieques and other Puerto Rican locations do not present an 

explicit public health hazard. 

Table 6-1. Average annual concentrations of PM10 and metals: Vieques and Fajardo, PR 

Vieques

PM10 As Cd Co Cu Fe Ni Pb V

23.6 0.00029 0.00002 0.0002 0.001 0.00033 0.0007 0.0009 0.0025

Fajardo 25.5 0.00023 0.00002 0.00014 0.002 0.00027 0.0008 0.0007 0.0019

CV 50 0.00020 0.01 0.1 150 2200 0.09 0.15 0.2

All data from (Gioda et al. 2007)

All data in μg/m3*

6.3. Findings

Every environmental dataset, whether based on direct sampled analyses or a modeling approach, 

includes simplifying assumptions and inherent uncertainties. Analytically measured data assumes the 

sampling device adequately captures the target substance, that the sampler is at the correct time and 

place relative to contaminant releases and exposures, and that the chemical/substance analyses 

produce accurate concentration estimates. Quality control and assurance procedures ensure that field 

sampling and laboratory measurement processes produce reliable results. That said, however, fieldsampling data remain only an estimate of real-world conditions. 

Quantitatively modeled datasets, such as the air dispersion model used in the Air PHA, resolve some 

direct sampling limitations—the modeled datasets allow estimation of results for any time or location. 

But air dispersion models necessarily include other assumptions, such as relevant contaminant emission 

rates, appropriate meteorological data, and specific aspects of the site terrain (e.g., topography). All of 

these site-specific conditions or model parameters influence air movement patterns. As with field 

sampling methods, air dispersion models also include quality assurance procedures to improve result 

quality. The Calpuff model used in the ATSDR Air PHA has undergone appropriate regulatory review. The 

U.S.EPA Support Center for Regulatory Atmospheric Modeling has approved the model for such uses as 

those employed by ATSDR. See: http://www.epa.gov/scram001.

Model assumptions and input parameters used in the ATSDR study are specifically documented in the 

2003 Air PHA Appendix D and further described by Wilhelmi et al. (2006). By overestimating numerous 

aspects of the contaminant emissions and by assessing exposures for worst-case conditions, the 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page | 132 

Figure 6-1a. 2005 Wind rose from Camp 

Garcia, Isla Vieques. 

Annual average wind speed is 1.46 meters per 

second. From CH2MHill 2007a.

Figure 6-1b. 2005 Wind rose from San Juan LM 

Airport. 

Annual average wind speed is 2.88 meters per 

second. From CH2MHill 2007a.

Figure 6-1c. 2005 Wind rose from Roosevelt 

Roads NAS. 

Annual average wind speed is 4.1 meters per 

second. From CH2MHill 2007a.

uncertainties inherent in this air dispersion model 

have been adequately addressed. And despite the 

overestimation of potential exposures, the model 

results indicate that in Viequense residential 

areas, airborne contaminants from historic uses of 

the Vieques Naval Training Range would have 

been essentially nondetectable. The PREQB’s 

historic and recent air sampling data and the 

Navy’s post-PHA air sampling and air dispersion 

modeling support these predicted results. 

Collectively then, the available data are adequate 

for the conclusions in the Air PHA. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011 

Page | 133 

6.4. Conclusions and Recommendations 

6.4.1. Conclusions 

1. This review of potential airborne exposures within the residential areas of Vieques to 

contaminants from military operations at the former Vieques Naval Training Facility is based on 

the following sources of information that were used in the 2003 ATSDR PHA: 

o U.S. Navy records of the types and amounts of ordnance used at the training range, 

o A source term model used to estimate the amounts of material produced by ordnance 

detonations, 

o An air dispersion model to estimate contaminant transport from the detonation area to the 

residential areas, 

o Long term meteorological data from the San Juan PR airport and the Roosevelt Roads Naval 

Station, and 

o Ambient air monitoring in the residential areas conducted by the PREQB for the 2001-2003 

time period. 

2. Also summarized are air monitoring data and air dispersion studies developed or collected after 

publication of the 2003 Air PHA for the purpose of evaluating ongoing or proposed open 

detonation or open burning. 

3. This review of potential airborne exposures evaluates the modeling process used in the 2003 Air 

PHA, the assumptions and data used in the modeling process, and compares the results of that 

modeling process with monitored data collected during recent open burning events. 

4. While this review finds the Air PHA modeling process consistent with established modeling 

practices, it does identify two minor errors in estimating detonation source concentrations. One 

results in an overestimate of metals concentrations. The other results in a minor underestimate 

of explosion byproducts in entrained soil that is overcompensated by the overall estimate of 

explosive compound concentrations. These errors do not affect the results or conclusions of the 

Air PHA. 

5. Collectively, the available sampled and modeled data are adequate for the determination of the 

potential public health hazard from exposure to airborne contamination. The uncertainties 

inherent in the 2003 ATSDR air dispersion model have been adequately addressed by 

overestimating numerous aspects of the contaminant emissions and by assessing exposures for 

worst-case conditions. Despite the overestimation of potential exposures, the model results 

indicate that airborne contaminants from historic uses of the Vieques Naval Training Range 

would have been essentially nondetectable in the residential areas of Vieques and unlikely to 

have resulted in harmful effects. These predicted results are supported by the PREQB’s historic 

and recent air sampling data and by the Navy’s post-PHA air sampling and air dispersion 

modeling. Collectively, the available data provide an adequate basis for the public health 

conclusions in the Air PHA. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 134

6. To conduct its health protective evaluation of potential exposures to airborne contaminants 

from military exercises at the former Vieques Naval Training Facility, the ATSDR Public Health 

Assessment used appropriate modeling procedures and available monitoring data. The 

additional air dispersion modeling and monitoring data conducted after completion of the Air 

PHA further support ATSDR’s public health conclusions. Because past military exercises would 

not likely have produced measurable concentrations of airborne contaminants in the residential 

areas of Vieques, no public health basis supports additional air studies or ambient air monitoring 

efforts related to past military exercises on Vieques.

7. Although the residents of Vieques could hear and possibly feel the explosions from military 

exercises on the former Vieques Naval Training Range, 8 miles is still a considerable distance. 

The physics of sound and seismic wave migration are very different from the physics of 

atmospheric dispersion of airborne particulates and gases.

6.4.2. Recommendations

No further recommendations at this time.

6.5. References

Army Research Laboratory, 2000. COMBIC, Combined Obscuration Model for Battlefield Induced 

Contaminants: Volume 1-Technical Documentation and Users Guide. Authors: Alan Wetmore; Scarlett 

D. Ayres; Army Research Laboratory, Adelphi MD. 2000 Aug. Available at: 

http://www.stormingmedia.us/44/4492/A449283.html. 

[ATSDR] Agency for Toxic Substances and Disease Registry. 2003. Public Health Assessment, Air Pathway 

Evaluation, Isla De Vieques Bombing Range Vieques, Puerto Rico. Atlanta: US Department of Health 

Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry; 2003 Aug 26.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2004. Guidance Manual for the Assessment 

of Joint Toxic Action of Chemical Mixtures. Atlanta: US Department of Health Human Services, Public 

Health Service. May. Available at: http://www.atsdr.cdc.gov/interactionprofiles/ipga.html . Accessed 

April 1, 2010.

Bjorkland et al. 1998. Open Burn / Open Detonation Dispersion Model (OBODM) User’s Guide, Volume 

1. User’s Instructions, DPG Document No. DPG-TR-96-008a. Prepared for the U.S. Army Dugway Proving 

Ground, West Desert Test Center. Meteorology & Obscurants Division. 2003 February. Model revision 

2003 May 15.

CH2MHill. 2007a. Air Dispersion Modeling of the TCRA/BIP Activities on the Former Vieques Naval 

Training Range (Draft). Herndon, VA: US Navy Contract Task Order 0047, prepared by CH2MHill; 2007 

Feb. 

CH2MHill. 2007b. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training 

Range: August 2005 through December 2006 (Draft). Herndon, VA: US Navy Contract Task Order 0047, 

prepared by CH2MHill; 2007 Feb.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 135

CH2MHill. 2007c. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training 

Range: January 1, 2007 through March 31, 2007 (Draft). Herndon, VA: US Navy Contract Task Order 

0047, prepared by CH2MHill; 2007 Jun.

CH2MHill, 2008a. Air Dispersion Modeling for TCRA-Prescribed Vegetation Burns on the Former Vieques 

Naval Training Range (Draft Final). Herndon, VA: US Navy Contract Task Order 0047, prepared by 

CH2MHill; 2008 Jun. 

CH2MHill. 2008b. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training 

Range: April 1, 2007 through June 30, 2007 (Draft). Herndon, VA: US Navy Contract Task Order 0047, 

prepared by CH2MHill; 2008 Jan.

CH2MHill. 2009. BIP Air Monitoring Data Summary Report for the Former Vieques Naval Training Range: 

January 1, 2008 through June 30, 2008 (Draft). US Navy Contract Task Order 0047, prepared by 

CH2MHill, Herndon, VA; Feb 2009.

Cruz Pérez 2000. Contaminacion Producida por Explosivos y Residuos de Explosivos en Vieques, Puerto 

Rico. Ing Rafael Cruz Pérez. Dimension magazine, 2:11-18. June 2000.

[ERG] Eastern Research Group. 2001. Vieques Air Monitoring Program. Prepared for the Agency for Toxic 

Substances and Disease Registry, Division of Health Assessment and Consultation. Lexington, MA:

Contract No. 200-2009-10039, Task Order No. 9; 2001 Jan 22.

Gioda et al. 2007. Particulate matter (PM10 and PM2.5) from Different Areas of Puerto Rico. Fresenius 

Environmental Bulletin v. 16 No.8; 2007.

[IT] IT Corporation. 2000. Atlantic Division Naval Facilities Engineering Command, Air dispersion 

modeling and related analyses for Inner Range operations, Vieques, Puerto Rico. Knoxville, TN: February 

2000.

[TAM] TAMS Consultants. 1979. Draft Environmental Impact Statement: Continued Use of the Atlantic 

Fleet Weapons Training Facility Inner Range (Vieques). December 1979.

Trinity Consultants, 2002. Calpuff Air Dispersion Modeling Report-Final, Vieques, Puerto Rico. Submitted 

to Eastern Research Group, Lexington MA. Parsippany, NJ: Project 023101.0024; Jun 2002.

Wilhelmi JL, Tsakaloyannis MK, Heath CH, Weber WM, Kellam JA, Campbell GH. 2006. Public health 

assessment of air emissions from military training exercises on the island of Vieques, Puerto Rico. San 

Diego, CA: Presented at the Air and Waste Management Association's 96th Annual Conference and 

Exhibition

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 137

7. Soil Pathway

7.1. Introduction to Soil Pathway .................................................................................................. 138

7.1.1. Soil Exposure Pathways............................................................................................... 138

7.1.2. Assessment of Available Data...................................................................................... 140

7.1.3. Strengths and Limitations of Available Data for Assessing Soil Pathway .................... 141

7.2. Analysis................................................................................................................................... 142

7.2.1. Exposures of Protesters in the Live Impact Area During 1999–2000.......................... 143

7.2.2. Exposures in the Island’s Residential Areas................................................................. 144

7.2.3. Recent Surface Soil Sampling Data on Areas of Concern ............................................ 146

7.2.4. Recent Background Study Data ................................................................................... 146

7.2.5. Additional Considerations ........................................................................................... 147

7.3. Conclusions and Recommendations....................................................................................... 148

7.3.1. Conclusions.................................................................................................................. 148

7.3.2. Recommendations....................................................................................................... 148

7.4. References.............................................................................................................................. 149

Chapter 7 Summary

The following chapter evaluates the available data and information on Vieques soil contaminants 

and whether accidentally swallowing soil could make people sick. Indirect effects of soil 

contaminants through the terrestrial food chain are considered separately in Chapter 5, “Local 

Produce and Livestock Pathway.” ATSDR evaluated potential direct soil exposures in two situations: 

people who stayed on the LIA property during 1999–2000 protests and people who live in the 

island’s residential areas. 

Sufficient data are available to conclude that people who lived on the LIA during protests were not 

exposed to soil contaminants at levels high enough to cause adverse health effects. In the island’s 

residential areas, no soil data are adequate to characterize potential exposures fully. Nevertheless, 

consideration of soil data from other island locations and consideration of how contaminants might 

be transported through the air to residential areas suggests that in the island’s residential areas, 

exposure to military activity-related soil contaminants is not high enough to result in adverse health 

effects. Since ATSDR’s 2003 Soil PHA, more soil data have become available through investigations 

of known, localized areas of contamination on military lands. These were not areas accessed or

occupied by the protesters, so they do not affect the conclusions drawn for those exposures. They 

are also not from the residential portion of the island; therefore, they do not improve the residential 

evaluation. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 138

The recent data, along with the known presence of unexploded ordnance at the LIA, support the 

need for continuing to restrict access to the LIA and to other potentially contaminated military 

areas and the need to continue environmental assessment and remediation activities. To address 

remaining uncertainties about residential soil contamination issues, ATSDR recommends surface soil 

sampling in the island’s residential areas.

7.1. Introduction to Soil Pathway

Several studies have examined soil contaminant levels in the Live Impact Area and elsewhere on 

Vieques. ATSDR evaluated the available data to determine potential effects for two situations: people 

who lived in areas of the LIA during 1999–2000, and people who lived (in the past and currently) on 

residential portions of the island. The chapter includes the following subjects:

Ways in which people may be exposed to soil contaminants and ATSDR’s focus in this chapter on 

direct exposures; 

Documentation of available soil data, including a discussion of the strengths and limitations of 

the data for assessing exposures in the LIA or the residential portion of the island and a fresh 

analysis of the exposures of interest focusing on uncertainties in the available data; and

Discussion of how the above analysis might be affected by recently collected soil data in areas of 

concern or areas not affected by aerial bombing exercises, and a discussion of other 

considerations raised by interested parties related to soil exposures.

7.1.1. Soil Exposure Pathways

Environmental contaminants directly and indirectly affect the health of the planet and the people on it. 

ATSDR focuses on identifying exposures that might directly affect human health. For soil, we look at 

whether the small amount people might accidentally swallow or touch could contain enough of a 

particular chemical to cause health effects. Contaminated soil might also affect plants growing in it, 

which people might eat. And people might eat the animals that eat the plants growing in that 

contaminated soil. ATSDR considers such exposure pathways by looking at contaminant levels in the 

plants or animals that people actually use or eat. Characteristics of the contaminants, the soil, and the 

plants all affect the potential for plant uptake of contamination and may be important for food, 

medicinal, or ceremonial use of the plants or the animals feeding on them. For further information on 

exposure from plants or animals possibly affected by soil contaminants, please see Chapter 5 of this 

report, “Local Produce and Livestock Pathway.”

ATSDR identified several ways soil contaminants might directly affect Viequenses. We considered past 

(i.e., both during military exercises and after), present (i.e., the past few years, after cessation of military 

exercises), and future potential soil exposure pathways. Table 7.1 below lists the identified direct-soil 

exposure pathways. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 139

For evaluating soil exposures from accidentally swallowing or touching soil, surface soil data are 

preferred. Generally, in day-to-day activities people are assumed to contact only the top few inches of 

soil. Household dust is also considered a soil pathway constituent, given that soil may contribute 

contaminants to dust when it is brought indoors on shoes or hands. Windblown soil may contribute 

contaminants to surface soil, but its health effects are generally considered part of the air pathway. This 

section lists considerations on the air pathway’s contribution to soil exposures, presumed to be the 

mechanism by which residential soil would have been initially contaminated by aerial bombing exercises 

several miles away in the LIA.

Table 7-1. Direct soil exposure pathways to people on Vieques

Time Frame: Past Point of 

Exposure

Exposed 

People

Status

Accidentally swallowing or touching 

airborne dust blowing from past military 

activities

Residential 

Area of Island

Residents of 

Vieques

No historical data; no way 

to confirm model 

predictions

Accidentally swallowing or touching 

surface soil or household dust 

contaminated by past military activities

Residential 

Area of Island

Residents of 

Vieques

No historical data; no way 

to confirm assumptions, 

except perhaps for 

inorganics

Accidentally swallowing or touching 

surface soil while residing on Live Impact 

Area (during 1999 and 2000)

Live Impact 

Area of Navy 

Property

Protesters 

Occupying 

Beach Camps

Surface soil results 

available for the period 

and location of interest. 

Evaluated in Previous 

Assessment

Accidentally swallowing or touching 

surface soil or subsurface soil while 

conducting construction or excavation 

activities

Current and 

former Navy 

Properties

Navy 

Personnel or

Contractors

Not evaluated at this time; 

focus on residents
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 140

Time Frame: Present Point of 

Exposure

Exposed 

People

Status

Accidentally swallowing windblown dust 

from Live Impact Area

Residential 

Area of Island

Residents of 

Vieques

Current Live Impact Area 

soil data show 

contaminants too low to 

harm health; therefore 

same conclusion for 

windblown dust

Accidentally swallowing or touching 

previously contaminated surface soil or 

household dust

Residential 

Area of Island

Residents of 

Vieques

No data available; could 

collect to confirm 

conclusions based on other 

locations

Accidentally swallowing or touching 

surface soil in restricted access navy 

activity areas

Current and 

former Navy 

Properties

Navy 

Personnel or 

Contractors; 

Trespassers

Current data available at 

specific locations; few 

contaminants above safe 

levels used for screening; 

difficult to generalize

Accidentally swallowing or touching 

surface soil or subsurface soil while 

conducting remedial activities

Navy Property

Navy 

Personnel or 

Contractors

Not evaluated at this time; 

focus on residents

Time Frame: Future (Potential) Point of 

Exposure

Exposed 

People

Status

More frequent exposure of civilians to 

surface soil in navy activity areas or 

former navy land

Current and 

former Navy 

Properties

Residents of 

Vieques

Specific areas need 

sampling / assessment 

before opening to public

7.1.2. Assessment of Available Data

Several investigations have analyzed Vieques soil samples: 

 In 1972, the U.S. Geological Survey collected and described metals concentrations of samples of 

the soil’s “C” horizon—in general, the parent rock beneath the surface soil and subsoil layers 

(Learned et al. 1973). This sampling was a reconnaissance geochemical survey for metals only 

and included 420 samples across the entire island. In a later report the data were re-reported 

(Marsh 1992).

 In 1978, soil samples collected from four locations within the Live Impact Area (LIA) and two 

locations in the Eastern Maneuver Area (EMA) were analyzed for explosives and explosion 

combustion products (Hoffsommer and Glover 1978; Lai 1978). The exact sampling locations 

and depths were not given in the reports describing this sampling.

 In 1998, to describe existing conditions before a proposed airport expansion project, five soil 

samples (4–12 inches below ground surface) from an area of the Naval Ammunition Support 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 141

Detachment (NASD) buffer zone were collected and analyzed for a range of potential 

contaminants (PMC 1998).

 In 1999, about 33 surface soil samples (0–6 inches below ground surface) were collected along 

the western border of the EMA and analyzed for explosive compounds (CH2MHill and Baker 

1999).

 In 1999 and 2000, soil and sediment samples from 55 locations were collected from the LIA and 

other locations and analyzed for metals and other inorganic compounds (Garcia et al. 2000). The 

report describing this sampling event states that samples were collected from direct bombimpact locations, stormwater runoff areas, adjoining conservation zones, and civilian areas, but 

exact locations of sampling and exact sampling depth and procedures were not given. Only the 

highest and second highest contaminant concentrations detected for 25 sample locations within 

the LIA were reported. 

 In 2000, 37 surface soil samples (0–6 inches below ground surface) were collected within the LIA 

and adjoining conservation zones, including specific areas in the LIA occupied by protesters in 

1999 and 2000 (CH2MHill 2000). These samples were analyzed for metals and explosives. 

Samples from the LIA were targeted to bomb craters or collection areas for stormwater runoff 

deemed likely to contain the highest level of explosive contaminants. Samples from protester 

camps were collected from locations thought to be representative of the general area.

 In 2001, to describe background conditions at the NASD, 24 surface soil samples (0–6 inches 

below ground surface) were collected and analyzed for inorganic compounds (CH2MHill 2002). 

 Since 2003, several investigations of sites in the EMA, the Surface Impact Area (SIA), and the 

NASD have included surface soil sampling of between 4 and 50 samples per site (CH2MHill 

2007a-c; 2008a-e). These investigations focused on known, localized areas of concern affected 

by Navy activities other than aerial explosive-ordnance exercises.

 In 2007, 40 surface soil samples (0–6 inches below ground surface) were collected from areas of 

East Vieques not obviously affected by Navy activities. The samples were analyzed for inorganic 

compounds to describe background conditions on eastern Vieques (CH2MHill 2007d).

7.1.3. Strengths and Limitations of Available Data for Assessing Soil Pathway

Some of the above-listed data are not appropriate for assessment of residents’ exposure to 

contaminants in Vieques soil. Thus to assess potential soil exposures, ATSDR focused on two pathways: 

exposures to protesters who occupied parts of the LIA in 1999 and 2000, and exposures to bomb-related 

contaminants of people in the island’s residential area. The following section describes the strengths 

and limitations of these applicable, available data.

7.1.3.1. Protesters Living in the Live Impact Area during 1999–2000

Although limited in number, the CH2MHill 2000 data are otherwise ideal for assessing exposures to 

protesters during 1999–2000: they match the locations and time people may have been exposed. Less 

specific information is known about the locations, analysis, and results reported in Garcia et al. (2000), 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 142

but the samples were taken at the same general area and at the appropriate time. In both sets of data, 

samples from the LIA were selected from areas thought to be the most contaminated (i.e., bomb craters 

and stormwater runoff collection areas). The samples then were intended to describe conservatively the 

contaminant levels within the LIA. But the small number of samples compared with the large land area 

of the LIA leaves a great deal of uncertainty as to whether actual “worst case” samples were collected. 

This is a common limitation of environmental sampling. A further limitation of both datasets is that they 

only apply to periods near the protester occupation. Finally, evaluating these datasets for health hazards 

of chemical constituents gives little information about other serious hazards of LIA occupation, such as 

physical hazards posed by unexploded ordnance.

7.1.3.2. Exposures in the Residential Area of the Island

Because of current Navy property access restrictions, most exposures today would occur only in the 

island’s residential areas. But the only data from the residential areas are the 1972 geological survey 

data, which just describe the soil’s “C” horizon27 and just analyze for metals content. These data were 

distributed across the residential and other areas of the island. They may not provide accurate or 

complete information about the surface soil people accidentally swallow or touch in their day-to-day 

activities. Although other data contain more complete contaminant information for soils at the surface, 

they were collected from uninhabited parts of the island. One limitation of these data in describing 

exposures is that they may not accurately represent residential exposures. Nevertheless, despite the 

limited nature of the available data on residential soil contaminant levels, ATSDR accessed a 

combination of information related to soil contaminant levels elsewhere on the island. ATSDR used this 

information 1) to model predictions of how contaminants could be transported through air to residential 

areas, and 2) to reach scientifically based conclusions about the likelihood of military exercises

contaminating residential soil at levels that could cause health effects. More information on the 

uncertainties posed by using limited data to evaluate soil exposures is provided below in 7.2, the 

Analysis section.

7.2. Analysis

Among other Vieques health concerns ATSDR received were those related to contaminant exposure 

from military exercises involving explosive-ordnance in the LIA. Because of current Navy property access 

restrictions, most exposures would take place today only in the island’s residential areas. During 1999 

and 2000, however, some protesters did occupy areas of the LIA. The following sections discuss the data 

available for assessing direct soil exposures of protesters living in the LIA during that period, and of 

Viequenses generally at other times in the past or present. In addition, surface soil sampling data 

obtained since ATSDR’s previous evaluation in 2003 are discussed as they relate to assessing potential 

soil pathway exposures.

 

27 In general, the parent rock beneath the surface soil and subsoil layers.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 143

7.2.1. Exposures of Protesters in the Live Impact Area During 1999–2000

In 2000, surface soil samples were collected from the specific LIA locations where protesters lived in 

1999 and 2000, as well as other LIA locations (CH2MHill 2000). Samples included low-lying areas that 

stormwater runoff would likely affect. Around the same time, an independent organization also 

collected soil samples at the LIA and in areas where people lived during 1999–2000 (Garcia et al. 2000). 

For this sampling, the exact location, depth of sampling, and full results were not reported. Because the 

Garcia et al. report stated that the intent of the study was to characterize exposure, in its previous 

evaluation ATSDR considered the results as surface soil samples. This resulted in conservative exposure 

estimates because Garcia et al. only reported the highest and next-to-highest values detected. ATSDR’s 

inclusion of these reported values in estimating average exposures biased the estimate to the high side. 

Although limited in number, the surface soil samples collected during 2000 were nearly ideal for 

assessing exposures to people occupying the LIA. Both in space and time the samples were 

representative of the soil people may have contacted while they were there. The CH2MHill 2000 data 

report included documentation of high standards of data quality such as quality assurance/quality 

control and chain of custody forms.

In its previous assessment, ATSDR estimated doses using the highest concentration measured in the 

locations where protesters lived; the doses were all below then-current health effects levels (ATSDR 

2003). Some critics of this analysis suggested that people in the camps might have been exposed to 

contaminants in other parts of the LIA. In response we examined whether our conclusion would change 

if we used the average inorganic contaminant concentrations measured throughout the LIA as an 

exposure concentration (a person spending time in both the camp and in other parts of the LIA would 

have an average exposure over all the surface soils encountered). Although the average exposure 

concentrations were biased high because the averages included only the maximum and second highest 

soil measurement detected from the Garcia et al. study (2000), the concentrations were only slightly 

higher than the maximum camp value used in ATSDR’s previous assessment. Following the reasoning of 

the previous public health assessment, exposure to these concentrations in surface soil would not be 

expected to result in adverse health effects (ATSDR 2003). ATSDR also looked at surface soil explosives 

data from other locations of the LIA collected in 2000 (CH2MHill 2000). Although those samples showed 

rare detections of HMX, RDX, 2-amino-DNT, and TNT, even the highest detected values were lower than 

screening values.28 The average soil concentration for every chemical measured is below the respective 

screening value, indicating that potential mixture effects are unlikely. 

Using the available data, we found no indication that protesters living on the LIA in 1999–2000 were 

exposed to harmful levels of surface soil contaminants. A strength of this conclusion is that the camp 

data were collected specifically to assess this exposure and were collected to represent the camps 

where protesters lived. In addition, the LIA samples were collected to assess the most contaminated 

areas on the LIA, so the conclusions would be based on contaminant levels that were biased high and 

 

28 Levels at which no adverse health effects would be expected from even continual exposure.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 144

would be more protective. A limitation is that, as with any evaluation of this type, conclusions must be 

based on a small number of samples. If further sampling were to show the earlier sampling did not 

result in a conservative or representative description of the area of exposure, the previous conclusions 

might not be valid.

Another limitation of using these data to assess exposure is that they apply only to the specific scenario 

described. That is, is the data are restricted to protesters living in camps on the LIA in 1999–2000. In the 

years long before 1999-2000, contaminant levels (especially explosives) could have been much higher 

and could have had the potential for short- or long-term health effects (we have no way of obtaining 

these data today). Also, despite the fact that around the year 2000 the surface soil contaminant levels in 

the LIA were not high enough to expect adverse health effects, that finding alone does not mean people 

could safely occupy the LIA. Physical hazards remained, such as unexploded ordnance that could cause 

immediate injury or death to those who inadvertently disturbed it. Because these hazards remain, 

limiting access to the LIA and to other contaminated military areas is essential for protecting public 

health—at least until those areas undergo a complete environmental assessment and cleanup.

7.2.2. Exposures in the Island’s Residential Areas

Lack of surface soil data is a major limitation for assessing soil exposure in the island’s residential areas. 

The only soil data available from this section of the island were the 1972 U.S. Geological Survey data 

(Learned et al. 1973). Although the sample points were well distributed across residential and other 

areas of the island, the data described only sampling of the soil’s “C” horizon (in general, the parent rock 

beneath the surface soil and subsoil layers). The report did state that at many points the surface soil and 

subsoil layers were absent (i.e., the parent rock was exposed at the surface). But the specific samples to 

which this applied were not stated, and the sampling depth and conditions were not available on a 

sample-by-sample basis. Therefore, whether the “C” horizon data truly represent the surface soil people 

accidentally swallow or touch in their day-to-day activities is unknown. Moreover, whether the parent 

rock is exposed or not, analyzing the “C” horizon provides little if any information about surface 

deposition of airborne contaminants (i.e., the mechanism by which contaminants from explosiveordnance exercises are believed to reach soil).

Although the residential soil data were limited, ATSDR could use the limited data and other information 

to reach scientifically based conclusions about the potential for exposures to bombing-related 

contaminants in residential soil to result in adverse health effects. In its previous health assessment, 

because the residential data were limited, ATSDR used the USGS data and several other data sources 

from different areas of the island to evaluate the potential for residential exposure to soil to harm 

health (CH2MHill and Baker 1999; CH2MHill 2000; Garcia et al. 2000; Hoffsommer and Glover 1978; Lai 

1978; Marsh 1992; PMC 1998). The evaluation included data from 

 The LIA, 

 The Eastern Maneuver Area (EMA), 

 The EMA border, 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 145

 The residential area, and 

 The Naval Ammunition Support Detachment (NASD). 

ATSDR first compared a particular contaminant’s highest level found in any sample with screening levels 

below which no health effects would be expected. Contaminants above the screening level were 

evaluated further by estimating exposure doses based on an average soil concentration. None of the 

contaminants in soil were at levels expected to result in harmful effects (ATSDR 2003). 

The soil pathway public health evaluation conforms to ATSDR procedures for reaching public health 

decisions when only limited environmental data are available. In addition, the air modeling results, 

discussed in the previous chapter, support the hypothesis that exploded or unexploded ordnance did 

not contaminate residential soils to harmful levels. Models indicated that airborne contaminants would 

disperse to undetectable levels away from the Live Impact Area. 

Although the analysis of all the information indicated that health effects from exposure to contaminants 

in residential soil are unlikely, a point that needs reiteration is that the previous assessment’s 

assumptions contain uncertainty. When using discrete environmental samples to describe a large area, 

uncertainty is always present. This is particularly true when data collected at one location form the basis 

for conclusions about another, unsampled location. Additional data uncertainties include

 Averaging soil results that might include subsurface samples is not necessarily representative of 

the concentrations present in the surface soil that people in their normal activities accidentally 

swallow or touch. 

 Each investigation might have a different focus and might analyze for different sets of 

contaminants. Also, while inorganic contaminant levels are expected to remain relatively stable 

over time, other contaminant levels (e.g., those of volatile compounds, certain explosives) in 

surface soil might, through volatilization or chemical or biological degradation, be significantly 

reduced over time. Therefore, even if surface soil sampling were available, the results might not 

represent completely all potential past exposures. 

 The majority of the more recent surface soil data were collected in the LIA. Because the LIA was 

the focus of a citizen’s petition then under consideration, ATSDR’s previous assessment 

concentrated on describing potential residential soil effects using LIA data. Because 

contaminants from the LIA would be dispersed by the time they reached the residential area, 

using LIA data was assumed to represent “worst case” exposures possible from LIA activities. 

But Vieques was the site of past military activities other than those involving explosive ordnance 

(e.g., transportation, storage, general training). Conceivably these activities—or even 

nonmilitary activities—could result in different contaminant profiles in the residential portion of 

the island compared with the LIA. 

Such data limitations aside, ATSDR still maintains that any low-level, current residential area soil 

exposures to explosive ordnance-related contaminants in the LIA are unlikely to cause health effects. 

First, recent surface soil sampling in the LIA did not show contaminant levels of health concern. Second, 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 146

air modeling indicates that any windborne contaminants from the LIA would be dispersed to 

undetectable levels away from the LIA. Nevertheless, given the uncertainties described above, ATSDR 

has updated its previous conclusion (ATSDR 2003) to acknowledge these limitations and indicate that 

the historical data are insufficient to allow us to determine whether past exposures to explosives or 

other compounds in surface soil could have been high enough to increase a past risk of adverse health 

effects.

7.2.3. Recent Surface Soil Sampling Data on Areas of Concern

Since ATSDR’s first assessment, several site investigations in the EMA, the Surface Impact Area (SIA), and 

the NASD have included surface soil sampling (CH2MHill 2007a-c; 2008a-e). The investigations focused 

on known, localized areas of concern affected by Navy activities other than explosive ordnance. This 

means the surface soil samples were probably not representative of residential area surface soils. ATSDR 

performed a preliminary evaluation of the surface soil results from these investigations, focusing on 

maximum detections of inorganic compounds above background and detections of organic compounds. 

Although several sites had contaminants higher than screening values,29 current access restrictions due 

to ongoing remedial activity mean exposures to the public are unlikely. In any event, we saw no 

evidence that contamination associated with areas of concern was present outside the localized area. 

Examining the contaminants present may nonetheless provide clues to contaminants previously 

unrecognized but of possible concern in the residential area. For example, certain recent investigations 

have shown isolated detections of pesticides, semivolatile compounds, explosives, and dioxin 

compounds. We repeat that we have found no evidence these areas of contamination have spread 

beyond their isolated, local areas. Agencies responsible for characterizing the nature and extent of 

contamination in the future should ensure that all potential sources and contaminants are considered.

7.2.4. Recent Background Study Data

Recent soil background studies at the NASD and on East Vieques (the EMA) characterized the soils in 

areas not “impacted” by Navy operations—that is, not close to known, localized areas of concern and 

not in the runoff path from known military operations areas (CH2MHill 2001; CH2MHill 2007d). As 

described in the previous chapter, evaluation of the air pathway indicates that airborne contaminants 

would hardly be detectable after dispersing away from the bomb impact area. Examining results from 

background locations (not directly affected by military exercises) could be a way to confirm that soils are 

not currently affected by past airborne fallout of contaminants from military operations. The NASD 

background study, however, only included inorganics, and the East Vieques background study only 

included inorganics and explosives. While inorganic contaminant levels are usually relatively stable over 

time, levels of other contaminants (e.g., volatile compounds, certain explosives) in surface soil might, 

through volatilization or chemical or biological degradation, substantially reduce over time. For this 

reason, the background soil data were not useful for conclusions about past exposures to explosives or 

present and past exposures for nonanalyzed potential contaminants. 

 

29 Levels at which no adverse health effects would be expected from even continual exposure.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 147

In background samples, very few contaminants were present above screening values.30 Only total 

chromium slightly exceeded a screening value for hexavalent chromium. Chromium is a naturally 

occurring element as well as a potential contaminant. In soils it is found in several forms, including the 

most toxic hexavalent form (ATSDR 2000). Although the relative proportions of all the different forms of 

chromium were not analyzed, much of the total chromium measured probably consisted of less toxic 

chromium forms. In the EMA, the explosive 2-amino-DNT was detected in one sample, but it was well 

below the applicable screening value. The residential area of the island was much farther from the past 

military activities than were the background samples collected in these investigations. Dispersal would 

result in contaminant concentrations even lower in the residential areas than in the background 

sampling areas. These background data, then, further support the hypothesis that contaminants in 

surface soil in Vieques residential areas are not at levels known to cause health effects today. Yet 

detection of explosive residues in the background samples also suggested that all areas of the island, 

including the residential area, might have been affected by explosive compounds from past bombing 

activities. Although residual levels are low today, it is impossible to say what past levels were.

7.2.5. Additional Considerations

Some Puerto Rican scientists suggested to ATSDR that evaluating surface soil samples collected from 0–6 

inches below land surface would underestimate potential exposure to contaminants present at high 

concentrations only at the very surface. To explore this concern, we considered alternate “worst case” 

concentration assumptions, such as assuming the contaminant was present only in the top inch rather 

than the entire 6 inches. 

For the available data, however, we determined this was an unrealistic assumption. Most surface soil 

data came from the LIA, where years of widespread bomb and projectile impacts and explosions would 

have stirred up huge amounts of soil; any resulting contaminants were likely distributed throughout 

more than just the top 6 inches. Likewise, many inorganic compounds are naturally present throughout 

soil and would never be completely absent, regardless of depth. 

Given these considerations, we decided an analysis of the available data assuming that all contaminants 

were present in the top inch of soil would be misleading. In future surface soil sampling events, ATSDR 

recommends that agencies or researchers explore this issue further by analyzing the top inch of soil 

separately from the typical 0–6 inches or 0–3 inches collected.

The conclusions and recommendations from ATSDR’s evaluation of the soil pathway are below and in 

Chapter 9 of this report. 

 

30 Levels at which no adverse health effects would be expected from even continual exposure.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 148

7.3. Conclusions and Recommendations

7.3.1. Conclusions

1. Those who occupied the LIA from 1999–2000 were not at increased risk of adverse health 

effects from exposure to surface soil contaminants. Supporting data are limited, but they are of 

good quality and represent the location and the period of interest. In the years before the late 

1990s tests, contaminant levels in the LIA (especially explosives) might have been higher, but we 

have no historical data with which to evaluate this assumption. 

2. This does not mean anyone can now safely visit the LIA. Remaining unexploded ordnance could 

cause immediate injury or death to anyone who might inadvertently disturb it. Recently 

collected data on specific areas of concern within military lands—not the same areas accessed 

and occupied by protesters—demonstrate the remaining potential for localized contamination, 

which, if people frequented those areas, could be of health concern. 

3. Limited available data from other locations and air pathway considerations suggest that the 

military exercises in the LIA did not result in current contamination of residential soils with 

inorganic or explosive compounds at levels considered harmful. ATSDR arrives at this conclusion 

using a scientific evaluation of the available data. But again, data from other areas are limited in 

number, data for all potential contaminants of concern are not available, and no adequate 

surface soil data are available from the residential area itself. ATSDR nonetheless understands 

that community members remain concerned about residential soil exposures. 

4. Modeling described in the air pathway discussion has suggested that airborne transport of 

contaminants during past military exercises would not have been substantial enough to have 

affected soils in the island’s residential area. Sufficient historical data are not available to 

confirm this, nor will such data ever become available. Consequently, we cannot determine 

whether past exposures to explosives or other compounds in surface soil could have been heavy 

enough to increase a past risk of adverse health effects.

7.3.2. Recommendations

1. Continue to restrict access to the LIA and other potentially contaminated military areas and 

continue environmental assessment and remediation activities to clear the way for public 

access.

2. To help address community concerns regarding residential soil, work with local residents to 

design sampling to identify residential surface soil quality issues, whether or not those surface 

soil issues relate to past military activities:

a. Focus initial sampling on areas identified as potential high-exposure areas, such as areas free 

of vegetation or child-use areas. 

b. To identify any possible differences in the top layer, initial sampling should analyze the top 

inch of soil separately from the rest of the 0–3 or 0–6 inch surface samples.

c. Perform a full range of analyses to identify all possible contaminants. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 149

d. Plan and conduct sample collection and analysis to ensure the results meet high data quality 

standards.

3. Although this sampling might provide inferences about past exposures for compounds stable 

over time, such as metals or other inorganic compounds, it will provide no definitive information 

on past surface composition and no information on past levels of compounds that react or 

degrade over time. 

4. ATSDR also recommends collection of representative soil samples as part of its evaluation of the 

terrestrial food chain pathway. See Chapter 5 of this report for details.

7.4. References

[ATSDR] Agency for Toxic Substances and Disease Registry. 2003. Public health assessment, soil pathway 

evaluation, Isla de Vieques bombing range. Atlanta: US Department of Health and Human Services; 

February.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2000. Toxicological profile for chromium. 

Atlanta: US Department of Health and Human Services; September.

[Baker] CH2MHill and Baker Environmental, Inc. 1999. Results of the hydrogeologic investigation: 

Vieques Island, Puerto Rico; November. 

CH2MHill 2000. Live impact area soil sampling report: US Naval facility, Vieques Island, Puerto Rico. 

Tampa FL: CH2MHill; October.

CH2MHill 2002. Final soil, groundwater, surface water, and sediment background investigation report, 

US Naval Ammunition Support Detachment, Vieques Island, Puerto Rico. Tampa, FL: CH2MHill; October. 

CH2MHill. 2007a. Remedial investigation report for solid waste management unit (SWMU) 6, CH2MHill; 

February.

CH2MHill 2007b. Remedial investigation report for area of concern (AOC) J, CH2MHill; May.

CH2MHill. 2007c. Remedial investigation report for area of concern (AOC) H, CH2MHill; July.

CH2MHill. 2007d. East Vieques background soil inorganics investigation report, former Vieques Naval 

Training Range. Tampa, FL: October.

CH2MHill. 2008a. Remedial investigation report for solid waste management unit (SWMU) 7. Tampa, FL: 

March.

CH2MHill. 2008b. Remedial investigation work plan addendum for solid waste management unit. 

Tampa, FL: (SWMU) 4; April. 

CH2MHill. 2008c. Final PA/SI report, 12 consent order sites and 8 PI/PAOC sites. Tampa, FL.

CH2MHill. 2008d. Remedial investigation report for area of concern (AOC) I. Tampa, FL: June.

CH2MHill. 2008e. Remedial investigation report for area of concern (AOC) E. Tampa, FL: July.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 150

Garcia N, Lopez AM, Soto M, Rosado S, Berrios B. 2000. Environmental impact of Navy activities in 

Vieques. San Juan, PR: Servicios Cientificos y Tecnicos, Inc.; July.

Hoffsommer JC and Glover DJ. 1978. Vieques litigation support: explosives analysis of water and soil 

samples taken on Vieques Island, Puerto Rico, May 11 through May 16, 1978. Silver Spring, MD: Naval 

Surface Weapons Center, Explosives Chemistry Branch.

Lai MG. 1978. Explosion products content of water and soil samples taken on Vieques Island, Puerto 

Rico, May 11 through May 16, 1978. Silver Spring, MD: Naval Surface Weapons Center; July.

Learned RE, Grove GR, Boissen R. 1973. A geochemical reconnaissance of the Island of Vieques, Puerto 

Rico. US Geological Survey and Puerto Rico Department of Natural Resources. Open-file report 73-155 

(order number 1866). 

Marsh SP. 1992. Analytical results for stream sediment and soil samples from the Commonwealth of 

Puerto Rico, Isla de Culebra, and Isla de Vieques. Open-file report 92-353A. Denver, CO: US Geological 

Survey.

[PMC] Program Management Company. 1998. Environmental baseline survey: 400-acre site, Vieques 

municipal airport expansion, Vieques Island, Puerto Rico, 00765. Annapolis, MD: PMC; November.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 151

8. Drinking Water Pathway

8.1. Introduction............................................................................................................................ 152

8.2. Assessment of Available Data................................................................................................. 152

8.2.1. Pipeline Water (Current Supply).................................................................................. 152

8.2.2. Public and Private Well Water..................................................................................... 153

8.2.3. Rainwater Collection Systems..................................................................................... 153

8.2.4. Strengths and Limitations of Available Drinking Water Pathway Data....................... 154

8.3. Analysis................................................................................................................................... 154

8.4. Conclusions and Recommendations....................................................................................... 157

8.4.1. Conclusions.................................................................................................................. 157

8.4.2. Recommendations....................................................................................................... 158

8.5. References.............................................................................................................................. 158

Chapter 8 Summary

The following chapter evaluates the available data and information on contaminants in past and 

present drinking water sources on Vieques and whether consuming drinking water could make 

people sick. ATSDR considered three past or present drinking water sources: the current pipeline 

supply, public and private supply wells used in the past and still occasionally used when pipeline 

water is interrupted, and rainwater collection systems that may have been used in the past and may 

still be used. 

ATSDR determined that the limited available sampling data on the pipeline water supply system and 

the public and private wells indicate almost all these drinking water supplies are acceptable for their 

current uses. One private well was found to contain nitrate-nitrite levels that could be harmful; 

ATSDR recommended no one drink from this well. Ongoing monitoring of the current pipeline 

source water is required to ensure the supply meets drinking water standards, and repeating 

previous sampling of storage tanks, residential taps, and wells still in use would address remaining 

uncertainty associated with conclusions about the pipeline water and public and private wells. A 

lack of adequate historical data prevents ATSDR from making any conclusion about distant past 

(1970s and 1980s) public supply well exposures. Also, no data are available to evaluate past or 

present rainwater collection systems exposures. Since ATSDR’s 2001 drinking water public health 

assessment, more groundwater data have been collected. These data are not from current drinking 

water sources, so they do not provide additional exposure information. One study, however, 

provided results supporting ATSDR’s previous conclusion that contaminants in groundwater at the 

LIA could not reach the public water supply wells. The other studies focused on locally contaminated 

areas of concern not used for drinking water; they support the continuing need for characterization 

and eventual cleanup of source areas resulting from past military activities on Vieques. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 152

In addition to required testing of the pipeline source water, ATSDR recommends repeated sampling 

of the current public water supply (storage tanks and residential taps) and public and private wells 

still available for use to confirm the safety of the drinking water for consumption. Also, ATSDR 

recommends further evaluation of the use of rainwater collection systems and sampling if such 

systems are used for drinking water.

8.1. Introduction

Many Viequenses remain concerned that military activities on and near the island might have 

contaminated Vieques drinking water, either currently or in the past. Vieques has or has had only three 

past or present drinking water sources:

1. Since 1978, the Puerto Rico Aqueduct and Sewer Authority (PRASA) has provided drinking water 

through a pipeline from the main island. In some years, these operations were conducted by private 

companies contracted by PRASA. After transport from Puerto Rico, water is stored in tanks on 

Vieques. Most Viequenses use this water source. 

2. Before 1978, public supply wells in the Esperanza well field (presumably operated by PRASA) and 

several private groundwater wells were sources of drinking water. Some of these wells are still used

whenever water pipeline service is interrupted.

3. Reportedly, individual households use rainwater collection systems as sporadic, supplemental 

drinking water sources. How prevalent the systems are, or were in the past, is unclear. 

ATSDR evaluated available data to describe the safety of these potential drinking water sources on 

Vieques. This chapter describes ATSDR’s data analysis.

8.2. Assessment of Available Data 

8.2.1. Pipeline Water (Current Supply) 

In summer of 1999, the U.S.EPA and PRDOH collected and analyzed water samples from storage tanks 

for water piped from the main island and from residential water taps on Vieques (PRDOH 1999; USEPA 

1999). To address quality control issues, in January 2000, U.S.EPA resampled some of the locations for 

explosives (USEPA 2000). In its previous assessment, ATSDR examined these data and found no 

contaminants above health or regulatory standards or obviously related to bombing activities, indicating 

that pipeline water was acceptable for consumption (ATSDR 2001). ATSDR recently obtained water 

quality reports of the source water dated from 2004–2009. These reports show that in 2004–2005, the 

action level for lead (15 g/L) was occasionally exceeded. This was attributed to corrosion in the piping 

system. In 2006–2007, the number of exceedances went up sharply, with 28 in 2007 alone. For that 

year, the 90th percentile of lead concentrations measured (the level below which 90% of the lead 

concentrations measured fall) was 144 g/L, greatly exceeding the action level. This level is a significant 

concern, especially to pregnant women and young children. The cause of the elevations in lead are 

unknown to ATSDR. But the water quality reports stated that immediate investigations were undertaken 

to identify the source of the lead and to address the problem. In 2008 and 2009, the number of 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 153

exceedances was low (2 in 2008 and 4 in 2009); the 90th percentile of lead concentrations measured was 

well below the action level in both years. 

To summarize, testing of the supplied water did not indicate any contaminants were related to military 

exercises on Vieques. Still, continued safety of the pipeline water supply relies on continued monitoring 

of the water supply according to federal regulations and, if necessary, on prompt action to address 

violations. 

8.2.2. Public and Private Well Water 

A 1978 sampling event reported low levels of explosives or explosives byproducts in drinking water 

samples taken from two public supply wells in Esperanza and Isabel Segunda (Hoffsommer and Glover 

1978; Lai 1978). In its previous assessment, ATSDR questioned these reported explosive detections 

because of the small number of samples collected and because the sample descriptions left uncertainty 

as to the samples’ identity and locations (ATSDR 2001). Even assuming the detections were present at 

that level in drinking water, the levels of explosives were too low to result in adverse health effects 

(ATSDR 2001). In 1995, PRDOH tested the public and private wells, as did U.S.EPA and Navy contractors 

in 1999 (PRDOH 1995a and 1995b; USEPA 1999; Baker 1999). ATSDR evaluated these results and found 

that most well water was safe to drink. One private well located on the residential portion of the island 

west of the EMA and LIA was found to contain high levels of nitrate-nitrite, which could pose a health 

hazard and were likely a result of agricultural activity or septic systems in the area. Residents were 

advised that this well’s water was not safe for consumption. In addition to sampling data, ATSDR 

evaluated the island’s geology and topography and concluded that activities at the Live Impact Area 

(LIA) were unlikely to affect groundwater in private and in former public supply wells—groundwater did 

not move in the direction of the wells (ATSDR 2001). Although wells used previously as public water 

supplies would have been subject to drinking water regulations, ATSDR did not review historical reports 

on the water quality from the 1970s and 1980s or before. On the basis of our experience reviewing 

historical records, even if the records had been maintained and could be found, too many questions 

would arise as to quality control measures used, adequacy of the analytical methods used, and analytes 

measured to make the historical records useful for assessing past exposures.

8.2.3. Rainwater Collection Systems

No information was available on rainwater collection systems. This included their prevalence, whether 

they had ever been used for drinking water, or whether they had ever been tested. In its previous 

Drinking Water PHA, ATSDR discussed but did not evaluate this potential exposure pathway. ATSDR had 

planned to learn about that pathway through its evaluation of the air pathway’s potential to transport 

contaminants to the residential portion of the island and potentially contaminate rainwater collection 

systems. As discussed in a previous chapter, this air analysis suggested the air pathway was unlikely to 

transport contaminants to the residential portion of the island at levels that might result in adverse 

health effects (ATSDR 2003). ATSDR did recommend that Puerto Rican authorities identify 

representative systems and test them to ensure those systems deliver safe water. To our knowledge, 

such sampling has not occurred (ATSDR 2001). ATSDR also recommended sampling sediment from 

rainwater collection systems as an indication of potential past water quality.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 154

8.2.4. Strengths and Limitations of Available Drinking Water Pathway Data 

8.2.4.1. Pipeline Water

The available data were collected and analyzed according to standard methods and procedures. But only 

one round of tank sampling occurred. Only one residential tap sample representative of the water 

supplied to residents was collected. It is possible that the available data may not fully represent the 

quality of this water source over time. In fact, recent water quality reports indicate that lead levels in 

the supplied water have exceeded drinking water standards, sometimes significantly, in some years. 

Although these elevated levels are not related to bombing activities, they highlight the need to monitor 

continually the public water supply to ensure its quality. According to the most recent water quality 

reports, lead levels in source water have only rarely exceeded standards since 2007. The levels of lead 

do not appear to be a current concern.

8.2.4.2. Public and Private Well Water

The available, recent data were collected and analyzed according to standard methods and procedures. 

But, similar to the pipeline water, only one or two rounds of sampling occurred, limiting the confidence 

that the recent results will fully represent the wells’ status over time. Regarding the historical sampling 

results from the 1970s, these data are insufficient for public health conclusions regarding past 

conditions. Only two samples were collected, and the sampling and the analysis lacked documented 

quality assurance. We assumed that any available water quality reports or testing from that period 

would be similarly limited.

8.2.4.3. Rainwater Collection Systems 

No information was available on the prevalence of rainwater collection systems—including whether 

they were ever used for drinking water or whether they were ever tested for contaminants. 

8.3. Analysis 

Scientists, Viequenses, and other Puerto Ricans questioned whether the island’s drinking water was 

safe. In response, ATSDR first evaluated the available data. The drinking water pathway’s public health 

evaluation conformed to ATSDR procedures for using limited available environmental data to reach 

public health conclusions. The focus was on exposures taking place at that time. Uncertainties did arise 

from the limited available data, which we discuss below. We also discuss new information that may add 

to the previous assessment of drinking water exposures in light of groundwater sampling data obtained 

since ATSDR’s 2001 evaluation.

8.3.1.1. Pipeline Water

In 1999–2000, only one round of sampling appears to have been done for the tanks and for the 

residential tap water representative of the water supplied to residents. While conditions in the tanks 

and the tap water are not expected to change over time, greater confidence in the safety of the storage 

and distribution of the municipal supply could be gained by repeating the sampling and increasing the 

number of samples collected at the point of use. Although Puerto Rico water authorities regularly test 

the source water, recent (2004–2009) water quality reports have indicated intermittent problems with 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 155

elevated levels of lead in the water. That water is from Puerto Rico and would not be affected by past 

military activities on Vieques. But regardless of the source, lead in drinking water is a concern, especially 

for pregnant women and growing children. Ongoing monitoring and prompt action to address drinking 

water violations are essential to ensure the pipeline water’s continued safety.

8.3.1.2. Public and Private Well Water

ATSDR identified two general uncertainties associated with the evaluation of the former public water 

supply wells and the private wells:

 Number of Data Points: The conclusions about the recent safety of the drinking water wells 

were based on one or two sampling events for each well (June–August 1995 and September 

1999). Because well conditions usually fluctuate over time, we would have greater confidence in 

the safety of water from these wells were multiple time points available, encompassing at least 

both the rainy and dry seasons. We recognize that due to shutdown, further sampling of some 

of the wells (e.g., Sun Bay) is impossible, and that if people are unable to drink the water, no 

exposure can occur. Also, that contaminants would fluctuate between extremely low levels and 

levels of health concern is unlikely. Further testing would nonetheless engender greater 

confidence in the conclusion. 

 Lack of Historical Data: The arguments given in the previous assessment support the conclusion 

that groundwater movement is impossible from the Live Impact Area to the aquifers used for 

drinking water. ATSDR’s previous assessment focused only on explosive ordnance in the Live 

Impact Area—that was the focus of the petition then under consideration. But other military 

activities took place on Vieques, such as transportation, storage, and general training. These 

activities could have had spills or other releases that resulted in contaminants reaching the 

former public water supply. In addition, nonmilitary contaminant sources, such as spills, sanitary 

landfills, septic systems, or agricultural run-off, could also have affected the former public water 

supply. That explosives are or were recently present in the aquifer supplying the former 

municipal wells is unlikely, given that in the late 1990s nearby wells showed no detections. Yet 

explosives were possibly detected in the 1978 samples. But this detection was uncertain: only 

two samples were collected, and any mechanism by which the explosives could have entered 

the groundwater is unknown. 

Still, to be completely rigorous, we cannot dismiss entirely the possibility that explosive residues might 

have been present in the past in the drinking water supply. If such possible explosives detections were 

representative of the typical level in the public drinking water, that level was too low to result in health 

effects. But too few historical data points are available to confirm this conclusion. When the public 

supply wells were in operation, the owner would have been subject to drinking water regulations and 

should have collected and maintained water quality testing results. As described previously, however, 

ATSDR did not attempt to gather historical information on the water quality of these wells. Assuming 

data and testing reports were kept from the 1970s-1980s and could be located, numerous questions

would remain, such as the accuracy and precision of the analytical methods used, the quality control 

measures employed, whether all contaminants of potential concern were analyzed, and whether the 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 156

sampling in general was adequate to describe past water quality from the wells. Thus with regard to the

past condition of any well-supplied public water, sufficient data will never become available to establish 

fully its safety. 

8.3.1.3. Rainwater Collection Systems 

In its previous drinking water assessment, ATSDR did not evaluate this pathway—it remains a potential 

pathway of exposure. ATSDR’s later air modeling suggested that air transport was, historically and 

currently, not likely a major contamination source for rainwater collection systems. Still, to confirm that 

the water is safe, sampling of representative systems would be necessary. In its previous assessment, 

ATSDR recommended that Puerto Rico authorities identify example systems and test them to ensure 

they delivered safe water. To our knowledge, this sampling has not yet occurred. If sampling were 

conducted today (i.e., years after active bombing ceased), it would not answer the question of whether 

contaminants might have entered such systems in the past. ATSDR also recommended sampling 

sediment from rainwater collection systems as an indication of potential past water quality. This 

sampling would be limited to insoluble contaminants or to contaminants that had precipitated out of 

solution, had settled out, and had remained unchanged over time. But as stated previously for well 

water systems, for rainwater collection systems, complete information about every past potential 

contaminant and its past level will never become available.

8.3.1.4. Recent Data 

Since ATSDR’s 2001 assessment, several investigations have incorporated Vieques groundwater 

sampling. 

 In 2004, additional sampling was conducted for the wells along the western border of the 

Eastern Maneuver Area (EMA) (CH2MHill 2005). Groundwater analysis detected no explosives, 

semi-volatile organic compounds, herbicides, pesticides, PCBs, or dioxins. One inorganic 

(barium) and two volatile organic compounds (bromodichloromethane and chloroform) were 

detected above screening values.31 Because a groundwater flow study done in conjunction with 

the investigation showed that groundwater did not flow from the EMA toward the western 

border, such exceedances were thought more likely to result from background or from recharge 

of municipally treated water than from past military activities. ATSDR determined that all the 

substances found in the investigation were at levels not expected to cause adverse health 

effects if people drank the water. Although limited in scope, this study provided additional 

evidence supporting the former assessment’s conclusion: groundwater, even if contaminated by 

military operations, could not physically move westward toward the aquifers formerly used as a 

public water supply. The results of the study do not exclude the possibility for other 

groundwater contamination caused by military or nonmilitary activities hydrogeologically 

connected to the groundwater that supplies public and private wells.

 

31 Levels at which no adverse health effects would be expected from even continual exposure.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 157

 Other investigations conducted since ATSDR’s initial assessment have focused on characterizing 

the extent of contamination at localized groundwater areas of concern identified through the 

remedial process (CH2MHill 2007a–c;2008a–e). Several contaminants were found at levels that 

would make the associated groundwater unsuitable for consumption. These studies do not 

address potential drinking water sources. But they do support the need for characterization and 

eventual cleanup of source areas resulting from past military activities on Vieques.

The conclusions and recommendations from ATSDR’s evaluation of the drinking water pathway appear 

below and are in Chapter 9 of this report. 

8.4. Conclusions and Recommendations

8.4.1. Conclusions

1. The available sampling data of Vieques storage tanks and representative drinking water taps 

indicate that at the time of sampling, the public drinking water supplied via pipeline from Puerto 

Rico was acceptable to drink. This conclusion, however, is uncertain due to the limited number 

of samples and lack of additional rounds of confirmatory sampling. Public water supplies are 

tested regularly and have to meet water quality criteria. We have reviewed recent water quality 

reports indicating that lead levels have been a problem in the drinking water supply, although 

those problems appear to have been addressed now. Ongoing monitoring of the current 

pipeline source water and prompt action to address problems is required to ensure the supply 

meets drinking water standards.

2. Limited, late 1990s sampling data from public and private wells indicated that most of the wells 

are acceptable for occasional consumption, such as when the pipeline source is interrupted.32

Flow patterns preclude groundwater from the east (where most military operations occurred) 

affecting the public aquifers. And with the exception of one well, all groundwater contaminants 

were below ATSDR health screening values. But again, confidence in the conclusions is 

tempered by the limited number of sampling rounds, which might not have captured seasonal 

fluctuations in contaminant levels. Also, a lack of adequate historical data prevents ATSDR from 

making any conclusion about past public supply well exposures (i.e., the 1970s and 1980s). 

3. Although additional sampling might change the result, ATSDR confirms its previous conclusion 

that nitrate-nitrite levels in one private well would pose a health hazard, especially to children. 

Regardless of the source of this contamination, water from this well should not be consumed 

unless proven safe by further, comprehensive testing. 

4. No data are available to evaluate rainwater collection systems for past or present exposure 

potential to contaminants. Rainwater collection systems remain a potential exposure pathway.

 

32 Although the “Sun Bay” public wells have been abandoned, to our knowledge the “B” public wells and the 

private wells can still supply drinking water.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 158

5. Past military activities did affect groundwater, but the affected groundwater is not currently 

used for drinking water.

8.4.2. Recommendations

1. Continue required monitoring of the public water supply source water and take prompt action 

to address any exceedances of drinking water standards. Repeat the 1999–2000 storage tank 

and residential tap sampling, including a wider selection of representative taps. This could 

confirm the conclusion that the present public water supply is acceptable to drink.

2. Conduct additional sampling of the wells still available for use during pipeline service 

interruptions. This too could confirm the safety of drinking water from these wells.

3. Determine whether people drink water from rainwater collection systems, and if so, test the 

collected water to evaluate its safety. Additionally, sample the sediment from these systems; 

the sample results might provide limited information about the water’s past quality.

4. Do not use groundwater beneath the LIA and other former military operations for drinking 

water; continue environmental assessment and remediation activities to identify and clean up 

impacted groundwater.

8.5. References

[ATSDR] Agency for Toxic Substances and Disease Registry. 2001. Public health assessment, drinking 

water supplies and groundwater pathway evaluation, Isla de Vieques bombing range. Atlanta: US 

Department of Health and Human Services; October.

[ATSDR] Agency for Toxic Substances and Disease Registry. 2003. Public health assessment, air pathway 

evaluation, Isla de Vieques bombing range. Atlanta: US Department of Health and Human Services; 

August.

[Baker] Baker Environmental, Inc. 1999. Vieques groundwater sampling information. Coraopolis, PA: 15 

November.

CH2MHill. 2005. Draft final groundwater baseline investigation at US Navy's Eastern Maneuver Area, 

Former Atlantic Fleet Weapons Training Facility. Tampa, FL: May. 

CH2MHill. 2007a. Remedial investigation report for solid waste management unit (SWMU) 6, CH2MHill; 

February 2007.

CH2MHill. 2007b. Remedial investigation report for area of concern (AOC) J, CH2MHill; May 2007.

CH2MHill. 2007c. Remedial investigation report for area of concern (AOC) H, CH2MHill; July 2007.

CH2MHill. 2008a. Remedial investigation report for solid waste management unit (SWMU) 7. CH2MHill; 

March 2008.

CH2MHill. 2008b. Remedial investigation work plan addendum for solid waste management unit 

(SWMU) 4, CH2MHill; April 2008. 

CH2MHill. 2008c. Final PA/SI report, 12 consent order sites and 8 PI/PAOC sites. CH2MHill; June 2008.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 159

CH2MHill. 2008d. Remedial investigation report for area of concern (AOC) I, CH2MHill; June 2008.

CH2MHill. 2008e. Remedial investigation report for area of concern (AOC) E, CH2MHill; July 2008.

Hoffsommer JC and Glover DJ. 1978. Vieques litigation support: explosives analysis of water and soil 

samples taken on Vieques Island, Puerto Rico, May 11 through May 16, 1978. Silver Spring, MD: Naval 

Surface Weapons Center, Explosives Chemistry Branch.

Lai MG. 1978. Explosion products content of water and soil samples taken on Vieques Island, Puerto 

Rico, May 11 through May 16, 1978. Silver Spring, MD: Naval Surface Weapons Center; July.

[PRDOH] Puerto Rico Department of Health. 1995a. Data Sheets concerning contamination at three Sun 

Bay wells on Isla de Vieques. San Juan, Puerto Rico; May.

[PRDOH] Puerto Rico Department of Health. 1995b. Data Sheets concerning contamination at four B 

wells on Isla de Vieques. San Juan, Puerto Rico; May.

[PRDOH] Puerto Rico Department of Health. 1999. Investigation of the potable water in Vieques (in 

Spanish). San Juan, Puerto Rico: August.

[USEPA] US Environmental Protection Agency. 2000. Sampling of the Rio Blanco filter plant and Vieques 

public water supply tanks, Island of Vieques, January 18–19, 2000.

[USEPA] US Environmental Protection Agency. 1999. Vieques, Puerto Rico potable water storage tank 

and well sampling report, Vieques, PR, September 27–28, 1999

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 161

9. Conclusions and Recommendations

9.1. Introduction............................................................................................................................ 161

9.2. Consumption of Fish from Reefs off the Vieques Coast......................................................... 162

9.2.1. Conclusions.................................................................................................................. 162

9.2.2. Recommendations....................................................................................................... 164

9.3. Biomonitoring......................................................................................................................... 165

9.3.1. Conclusions.................................................................................................................. 165

9.3.2. Recommendations....................................................................................................... 166

9.4. Health Outcome Data ............................................................................................................. 167

9.4.1. Conclusions.................................................................................................................. 167

9.4.2. Recommendations....................................................................................................... 167

9.5. Local Produce and Livestock Pathway.................................................................................... 167

9.5.1. Conclusions.................................................................................................................. 167

9.5.2. Recommendations....................................................................................................... 168

9.6. Air Pathway............................................................................................................................. 169

9.6.1. Conclusions.................................................................................................................. 169

9.6.2. Recommendations:...................................................................................................... 170

9.7. Soil Pathway............................................................................................................................ 170

9.7.1. Conclusions.................................................................................................................. 170

9.7.2. Recommendations....................................................................................................... 171

9.8. Drinking Water Pathway......................................................................................................... 172

9.8.1. Conclusions.................................................................................................................. 172

9.8.2. Recommendations....................................................................................................... 172

9.9. Final Summary ........................................................................................................................ 173

9.1. Introduction

As part of ATSDR’s evaluation of Vieques, we have evaluated multiple documents and reports. We 

visited Vieques, where we discussed public health concerns with local officials, with scientists, and with 

the Viequenses themselves. We held a meeting with other scientists in which we discussed the most 

current Vieques research and studies. Our conclusions and recommendations for the Vieques site and 

community regarding the environmental media, biomonitoring, and health outcomes follow. During the 

public comment period for this report, CDC/ATSDR will consult with environmental and public health 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 162

agencies to determine how our recommendations may be implemented, by whom, and timelines for 

implementation.

9.2. Consumption of Fish from Reefs off the Vieques Coast

9.2.1. Conclusions

During ATSDR’s November 2009 meeting, several scientists raised concerns about mercury levels in fish. 

In particular, they were concerned that the conclusions in ATSDR’s 2003 Fish PHA were inconsistent with 

the 2004 U.S.EPA/FDA national advisory concerning mercury. Therefore, ATSDR reviewed its 2003 

conclusions and recommendations about mercury in fish from reefs surrounding Vieques. 

In its 2003 public health assessment regarding fish consumption, ATSDR used fish intake rates that 

focused on adults who ate 8 ounces of fish daily and who weighed 70 kg (or 154 pounds). Daily fish 

intakes rates for children were 4 ounces and children were assumed to weigh 16 kg (or 35 pounds). 

Estimated doses were compared with ATSDR’s MRL of 0.3 μg/kg/day, which was derived from an 

analysis of the Seychelles Island and Faroese studies. In ATSDR’s evaluation as presented in this report, 

ATSDR used a broad range of daily fish intakes and body weights. Using information from U.S.EPA’s 

Exposure Factor Handbook, ATSDR assumed that daily fish intakes for adult women were as high as 14 

ounces—the 99th percentile—and that women weigh as little as 46 kg (or 100 pounds). For children, 

ATSDR assumed that daily fish intakes were as high as 6 ounces for 1- to 2-year old children, 8 ounces 

for 3- to 5-year old children, 10 ounces for 6- to 14-year old children, and 20 ounces for 15- to 18-year 

old children. The highest intakes for children represent the 99th percentile portion size for the stated 

ages. In addition, ATSDR used the NAS’s recommendations and U.S.EPA’s Reference Dose (RfD) 

concerning mercury as well as human toxicity studies from the Faroe Islands. From its evaluation of 

mercury in Vieques fish, ATSDR reached these new conclusions:

1. ATSDR has identified mercury exposure from frequent consumption of marine seafood as a 

potential public health hazard. Women with a varied fish diet who typically eat more than 2 oz 

of fish every day have estimated mercury doses that exceed U.S.EPA’s chronic RfD. As portion 

size increases, the estimated doses approach the lowest level known to cause harmful effects to 

the developing fetus. ATSDR concludes that if these women are pregnant, their developing baby 

has a small increased risk of neurological effects later in life. The risk of harmful effects increases 

as portion size increases. Possible harmful effects identified from studies of non-Viequense 

children exposed in utero involve language, attention, and memory, and to a lesser extent 

visual/spatial and motor functions. 

2. Women who eat grunt or hind more frequently than other reef fish and who typically eat more 

than 2 oz of fish every day have estimated mercury doses two times higher than women who 

eat a varied fish diet. As portion size increases, the estimated doses for women who eat larger 

portions daily (e.g., 10 to 14 oz) approaches or exceeds the lowest level known to cause harmful 

effects in the developing fetus. ATSDR concludes that if these women are pregnant, their 

developing baby has a small increased risk of neurological effects later in life. The risk of harmful 

effects increases as portion size increases. Possible harmful effects identified from studies of 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 163

non-Viequense children exposed in utero involve language, attention, and memory, and to a 

lesser extent visual/spatial and motor functions. 

3. Children with a varied fish diet who typically eat more than 0.5 oz of fish every day have 

estimated mercury doses that exceed U.S.EPA’s chronic RfD. These children have a small risk of 

neurological effects. But as portion size increases, the risk of harmful effects increases. 

Depending upon their age, children as young as 1 year who eat 3 to 4 ounces of fish every day 

have estimated doses that exceed doses known to cause neurological effects and have the 

greatest risk of harmful neurological effects. Possible harmful effects identified from studies of 

non-Viequense children exposed in utero involve language, attention, and memory, and to a 

lesser extent visual/spatial and motor functions.

4. Like women, children who eat grunt and hind more frequently than other reef fish have 

estimated doses two times higher than children who eat a varied fish diet. The estimated doses 

in these children exceed the doses associated with neurological effects.

5. Some uncertainty is associated with these findings because a person’s mercury response is itself 

somewhat uncertain. The uncertainty could be due to sex, genetics, health and nutritional 

status, or how mercury is handled in the body. In the three human studies that focused on 

mercury exposure from eating fish and seafood, the identification of the lowest-effect levels was 

uncertain. Estimating the mercury dose from eating reef fish was likewise uncertain, given that 

the dose could vary depending on the type, frequency, and quantity of fish eaten.

6. While ATSDR supports the U.S.EPA’s and the FDA’s national fish advisory, portions of the 

advisory do not apply to the Viequenses who rely heavily on local seafood. For example, the 

advisory discusses fish that Viequenses do not eat, such as pollock, catfish, and tilefish. In 

addition, the advisory recommends that if a local advisory is not available, people should not eat 

more 6 ounces of local fish and should not consume any other fish during the week. We include 

links to the advisory for informational use and have recommended an educational program 

about mercury in locally consumed fish. 

7. Residents need information so they can select local seafood lower in mercury over seafood 

higher in mercury. This will protect developing fetuses and young children from mercury in fish. 

For informational purposes only, the advisory and related information is available at: 

http://www.epa.gov/waterscience/fish/advice; http://www.fda.gov/Food/FoodSafety/ProductSpecificInformation/Seafood/FoodbornePathogensContaminants/Methylmercury/ucm115662.h

tm, and Chapter 2, Section 2.7 of this report, Appendix 2A-3.

8. For the 104 fish samples collected from the marine areas near Vieques and from the commercial 

fish market, the average mercury level was 0.1 ppm and the range was nondetectable to 0.33 

ppm. The mercury levels detected in Vieques reef fish are similar to levels reported by the FDA 

(FDA 2010). The mercury levels are in the low (0.02–0.2 ppm) to mid (0.2–0.6 ppm) mercury 

range identified by FDA in its recent risk and benefit assessment (FDA 2009). 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 164

9. ATSDR also conducted a statistical analysis of the 2001 fish data and concluded the following:

a. Mercury detected in the seafood is higher in two fish families (grunt and hind) compared 

with other families sampled (e.g., parrotfish and snapper). The average mercury 

concentration in grunt and hind was higher than U.S.EPA’s 0.049 ppm screening level. In 

testing some of the hypotheses, ATSDR used the overall average of 0.1 ppm to determine 

which families of reef fish were likely to exceed the overall average. 

b. Mercury levels in parrotfish were statistically lower than U.S.EPA’s 0.049-ppm screening 

level and lower than the 0.1-ppm overall average. 

c. All snapper were lower than U.S.EPA’s 0.049 ppm screening value. But an insufficient 

number of snapper were collected to determine whether the average snapper-mercury level 

was statistically different from the U.S.EPA 0.049 ppm screening level. A sufficient number 

of snapper were collected to determine that the average mercury level is statistically lower 

than the 0.1-ppm overall average. 

10. Mercury is present in most seafood and is particularly high in some fish species and low in other 

species. While mercury was a component of the detonators of some bombs, only small amounts 

of mercury were introduced to the Vieques environment from this source. This conclusion is 

supported by the low mercury levels in LIA soils, which appear to be at naturally occurring 

levels. Mercury levels in fish in and around the LIA are most likely the result of the global 

reservoir of mercury circulating in the environment.

11. Statistical analysis showed that some fish and shellfish had higher levels of some metals and 

lower levels of other metals–iron, aluminum, copper, zinc, arsenic, barium, potassium and 

selenium were all slightly higher. These metals are materials found in bombs and metal ships, 

suggesting possible localized contamination. But the levels were only slightly higher and the 

difference was only statistically significant when compared with a few other locations.

9.2.2. Recommendations

ATSDR recommends the following for consideration by environmental and public health agencies and 

scientists:

1. People who frequently consume marine seafood should follow available fish advisories and 

fishing restrictions in Vieques. Maintain the fishing restrictions in the waters adjacent to the LIA.

2. Conduct a survey of Vieques residents to determine the types, frequency, and quantity of fish 

consumed.

3. Conduct additional risk assessments and statistical analyses using new information gathered 

from the previously recommended fish consumption survey.

4. Collect and analyze additional fish samples from Vieques should the proposed survey and 

statistical analysis not provide sufficient public health information. Collect sufficient fish samples 

to allow analysis by species and by location.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 165

5. Develop an educational program about mercury in fish that incorporates local habits and 

information about Viequenses’ seafood consumption. Benefits accrue to the developing fetus 

with maternal intake of nutrients in seafood (FDA 2009) that can outweigh the concomitant 

intake of small amounts of mercury. The goal of this site-specific educational program should be 

to educate Viequenses about the benefits of eating seafood so they can choose fish lower in 

mercury and still maintain their healthy dietary customs of consuming local seafood.

9.3. Biomonitoring

9.3.1. Conclusions

1. Since 1999, Vieques has hosted at least five human biomonitoring investigations. Puerto Rican 

scientists, physicians, or the Puerto Rico Department of Health (PRDOH) conducted all of them. 

The PRDOH has conducted the most extensive sampling effort, collecting biological specimens 

from 500 randomly selected Viequenses. The PRDOH manuscript reported that in 20% of the 

participants, either

• Aluminum, lead, or mercury in blood; 

• Uranium, cadmium, or nickel in urine; or 

• Nickel or arsenic in hair 

exceeded the laboratory’s reference range. The PRDOH manuscript identified cigarette use and 

hair dyes, as well as the consumption of seafood, as possible sources for some but not all the 

elevated levels. The PRDOH manuscript acknowledged that for some residents, it could not 

identify the source of high metal levels in urine, hair, and blood. The PRDOH manuscript did not 

report mercury levels in hair. Results from Dr. Ortiz Roque’s investigations showed that some 

residents had elevated levels of mercury in hair, and that the most likely source was fish 

consumption; other possible sources, however, were not completely ruled out.

2. Data from these studies showed that in blood, urine, hair, or feces, some residents of Vieques 

had elevated levels of various metals. While some of these elevated levels might be explained 

by cigarette use, seafood consumption, or hair dyes, they do not account for all the elevated 

levels. In particular, biomonitoring results from Dr. Ortiz Roque showed that some Viequenses 

had elevated mercury in hair above 12 ppm, the level identified by the NAS to cause harm in 5% 

of fetuses exposed in utero. Dr. Ortiz Roque also showed that mercury in hair was associated 

with fish consumption. In contrast, the PRDOH study did not find excessive mercury levels in 

blood, although the study either did not measure for or did not report mercury levels in hair. 

Thus the prevalence of high mercury levels in Viequenses remains somewhat uncertain. Except 

for mercury, metal content in hair is difficult to interpret. Metals can bind directly to hair from 

the use of commercial hair products, making difficult any distinction between internal metal 

exposure via ingestion and inhalation and external exposure resulting from contact with the 

metal in the environment (e.g., shampoo, dyes, dirt). 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 166

3. These studies were unable to investigate each person’s environment to identify the source for 

those who had excessive metals in hair, urine, or blood. The PRDOH study came closest to 

identifying possible sources (e.g., cigarette and hair dye use, seafood consumption) but 

acknowledged an inability to identify the source or sources for all residents with excessive 

metals exposure. Either through the survey instrument or through an in-home visit, it may be 

possible to identify other sources that increase metal exposure, such as cooking utensils, metal 

residues in foods (e.g., tea and vegetables), consumption of drinks with metallic packaging, 

antacid formulations and antiperspirant formulations.

4. ATSDR remains cautious in making decisions about using hair as an indicator of exposure to 

environmental contaminants and as an indicator of risk of harmful effects. A major problem in 

interpreting metal concentrations in hair is whether the metal content resulted from internal 

exposure (e.g., from ingestion or inhalation) or from external exposure (e.g., the hair coming in 

contact with a metal-containing product). Currently, no washing method is capable of removing 

exogenous metal contaminants while leaving endogenous metals undisturbed. Chemicals such 

as methylmercury, which originate generally from dietary sources, suffer less from this 

drawback, provided unusual sources of inorganic mercury do not complicate the picture, (e.g., 

mercury vapor in occupational or home settings).

5. These biomonitoring results do not permit any conclusions about exposure to the bombingrelated contaminants. 

9.3.2. Recommendations

1. Viequenses may be exposed to mercury in fish and cadmium in pigeon peas. These exposures

may warrant additional environmental investigations, such as sampling locally grown produce 

for cadmium and gathering more information about fish consumption and possibly mercury in 

fish. The information could be used to decide whether to undertake human testing for mercury

and cadmium in blood or urine. If other environmental exposures are identified, additional 

human biomonitoring investigations may be considered. More detailed information about 

ATSDR’s recommendations concerning fish and locally grown produce can be found in Chapter 

2, Section 2.3.2 and Chapter 5, Section 5.3.2, respectively.

2. Although ATSDR is not recommending a comprehensive, systematic biomonitoring effort at this 

time, public health officials could consider a limited and focused human biomonitoring 

investigation following the release of this report. If a biomonitoring investigation is conducted, it 

should include a comparison group from mainland Puerto Rico. If requested, CDC/ATSDR subject 

matter experts will provide technical assistance and support to PRDOH in planning and 

conducting such an investigation.

3. Viequenses who remain concerned about exposure to mercury, cadmium, other metals, or 

metalloids should consult their healthcare provider to discuss the need for and cost of testing. A 

qualified laboratory should do the testing and analysis.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 167

4. CDC/ATSDR can provide a list of qualified laboratories that can perform the tests. And if 

requested, CDC/ATSDR can provide information to healthcare providers about tests for metals 

in biologic samples. 

9.4. Health Outcome Data

9.4.1. Conclusions

1. The documents ATSDR reviewed paint a complex health picture for Viequenses. The findings of 

these studies indicate elevations in chronic disease prevalence, cancer incidence, and cancer 

mortality among the population between Vieques and the rest of Puerto Rico. In addition, 

increased mortality in Vieques particularly from cancer may indicate lack of access to 

appropriate medical care. The limitations associated with these analyses, particularly the 

methodological concerns discussed in this report, introduce considerable uncertainty and make 

interpretation difficult. Some of the methodological concerns previously noted include more 

exhaustive cancer case finding in Vieques than the rest of Puerto Rico, differential follow-up, 

chronic disease prevalence estimates based on a symptom disease prevalence survey without 

medical record confirmation of health outcomes, and limited noncancer mortality data. 

Differential follow up and exhaustive case finding may result in biased estimates of cancer 

incidence and mortality. Uncertainty is also evident in the wide confidence intervals reported 

indicating imprecise estimates of cancer incidence and mortality ratios in Vieques relative to the 

rest of Puerto Rico (RCCPR 2009). This is not unusual when calculating estimates for small 

populations.

2 These findings can nonetheless serve as a guide for future investigations of Viequenses’ health 

status. 

9.4.2. Recommendations

Assess the feasibility of applying the SMART BRFSS methods for generating stable Vieques 

specific prevalence estimates on asthma, diabetes, hypertension, and other chronic diseases. 

9.5. Local Produce and Livestock Pathway

9.5.1. Conclusions

1. The overall data are insufficient to quantify adequately human exposures or draw any valid 

health conclusions about whether consuming locally grown produce and livestock would result 

in harmful health effects. 

2. Limited sampling data are available for pigeon peas, a staple food among Viequenses. 

Interpretation of these data is uncertain because of the lack of adequate QA/QC information for 

the analytical findings. 

• A preliminary data evaluation completed for this report has concluded that the level of 

cadmium reported in a few samples of locally grown pigeon peas would not contribute 

excess dietary cadmium to preschool children who eat less than 5 of the largest (6 ounces) 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 168

servings per week of locally grown pigeon peas. Adults who eat the largest serving sizes (12 

ounces) should limit intake to 11 servings per week. 

• Preschool children who eat a typical serving size (1.5 ounces) may eat up to 20 meals per 

week and adults who eat a typical serving (3 ounces) may eat up to 44 meals per week 

without exceeding recommended cadmium intake levels. 

• Exceeding recommended levels of cadmium in the diet would not typically result in 

immediate health harm. Excessive intake of cadmium over decades could contribute to 

harmful levels of cadmium accumulation in the kidneys, possibly resulting in kidney disease. 

Typically, only a very small fraction (5%) of cadmium in food is absorbed in the body, 

especially in individuals with healthy diets containing adequate amounts of essential 

minerals such as zinc, iron and calcium (Reeves and Chaney, 2008). 

3. Whether the limited sampling results are representative of cadmium concentrations in other 

locally grown pigeon peas is unclear; but the significant uncertainty in the evaluation stresses 

the need to conduct further sampling. 

4. Preliminary evaluation results and the totality of the available data suggest a potential for 

uptake of metals from soil into food crops—thus further investigation is warranted. To evaluate 

better this exposure pathway, ATSDR has recommended a collaborative effort to conduct 

additional sampling of locally grown foods.

9.5.2. Recommendations

ATSDR supports additional sampling and collaborative data collection to evaluate more thoroughly 

this human exposure pathway. The following recommendations are intended to promote collection 

of high quality data of maximum utility, and to minimize data uncertainties: 

1. Sampling data should represent edible portions of a cross-section of local produce from local 

farms, home gardens, and local markets. Sample produce that tends to accumulate heavy 

metals more easily (e.g., leafy vegetables such as lettuce and spinach) rather than leaves of 

grain or fruit crops.

2. Survey residents to identify the prevalence and type of locally grown and commonly consumed 

garden produce. Sampling plan design should include produce types identified from this survey. 

3. Collect representative surface soil samples at the same location and time that garden and farm 

produce samples are taken. Soil samples should be of appropriate depth to represent the root 

zone. 

4. Collect samples of meat and milk products from Vieques forage-consuming livestock.

5. To avoid false high or low values, sample collection and analysis should conform to high 

standards of data quality, including detailed quality assurance/quality control information, 

standard reference materials for analysis, and background correction. Design the sampling plan 

to collect a sufficient number of samples to ensure high statistical confidence.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 169

6. Collect samples from an appropriate background or control location for comparison with food 

samples produced on Vieques.

7. To facilitate exposure assessment, report data as consumed (wet weight).

8. Plan and conduct sampling protocols in collaboration with local scientists. One way to avoid 

misunderstandings about the data is for local scientists and an independent expert jointly collect 

and split several samples and provide analytical reports with QA/QC supporting information. A 

QA/QC standard could be split at the time the samples are collected.

9. Request technical assistance from the U.S. Food and Drug Administration (FDA) or the U.S. 

Department of Agriculture (USDA) in sample collection and analytical protocols. The USDA 

Agriculture Research Service has offered to provide, if requested, technical assistance in 

sampling plan design, collection, and analysis with proper QA/QC protocols.

9.6. Air Pathway

9.6.1. Conclusions 

1. This review of potential airborne exposures within the residential areas of Vieques to 

contaminants from military operations at the former Vieques Naval Training Facility is based on 

the following sources of information that were used in the 2003 ATSDR PHA: 

 U.S. Navy records of the types and amounts of ordnance used at the training range, 

 A source term model used to estimate the amounts of material produced by ordnance 

detonations, 

 An air dispersion model to estimate contaminant transport from the detonation area to the 

residential areas, 

 Long term meteorological data from the San Juan PR airport and the Roosevelt Roads Naval 

Station, and 

 Ambient air monitoring in the residential areas conducted by the PREQB for the 2001-2003 

time period. 

Also summarized are air monitoring data and air dispersion studies developed or collected after 

publication of the 2003 Air PHA for the purpose of evaluating ongoing or proposed open 

detonation or open burning.

2. This review of potential airborne exposures evaluates the modeling process used in the 2003 Air 

PHA, the assumptions and data used in the modeling process, and compares the results of that 

modeling process with monitored data collected during recent open burning events. 

3. While this review finds the Air PHA modeling process consistent with established modeling 

practices, it does identify two minor errors in estimating detonation source concentrations. One 

results in an overestimate of metals concentrations. The other results in a minor underestimate 

of explosion byproducts in entrained soil that is overcompensated by the overall estimate of 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 170

explosive compound concentrations. These errors do not affect the results or conclusions of the 

Air PHA.

4. Collectively, the available sampled and modeled data are adequate for the determination of the 

potential public health hazard from exposure to airborne contamination. The uncertainties 

inherent in the 2003 ATSDR air dispersion model have been adequately addressed by 

overestimating numerous aspects of the contaminant emissions and by assessing exposures for 

worst-case conditions. Despite the overestimation of potential exposures, the model results 

indicate that airborne contaminants from historic uses of the Vieques Naval Training Range 

would have been essentially nondetectable in the residential areas of Vieques and unlikely to 

have resulted in harmful effects. These predicted results are supported by the PREQB’s historic 

and recent air sampling data and by the Navy’s post-PHA air sampling and air dispersion 

modeling. Collectively, the available data provide an adequate basis for the public health 

conclusions in the Air PHA. 

5. To conduct its health protective evaluation of potential exposures to airborne contaminants 

from military exercises at the former Vieques Naval Training Facility, the ATSDR Public Health 

Assessment used appropriate modeling procedures and available monitoring data. The 

additional air dispersion modeling and monitoring data conducted after completion of the Air 

PHA further support ATSDR’s public health conclusions. Because past military exercises would 

not likely have produced measurable concentrations of airborne contaminants in the residential 

areas of Vieques, no public health basis supports additional air studies or ambient air monitoring 

efforts related to past military exercises on Vieques.

6. Although the residents of Vieques could hear and possibly feel the explosions from military 

exercises on the former Vieques Naval Training Range, 8 miles is still a considerable distance. 

The physics of sound and seismic wave migration are very different from the physics of 

atmospheric dispersion of airborne particulates and gases. 

9.6.2. Recommendations:

No further recommendations at this time.

9.7. Soil Pathway

9.7.1. Conclusions

1. Those who occupied the LIA from 1999–2000 were not at increased risk of adverse health 

effects from exposure to surface soil contaminants. Supporting data are limited, but they are of 

good quality and represent the location and the period of interest. In the years before the late 

1990s tests, contaminant levels in the LIA (especially explosives) might have been higher, but we 

have no historical data with which to evaluate this assumption.

2. This does not mean anyone can now safely visit the LIA. Remaining unexploded ordnance could 

cause immediate injury or death to anyone who might inadvertently disturb it. Recently 

collected data on specific areas of concern within military lands—not the same areas accessed 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 171

and occupied by protesters—demonstrate the remaining potential for localized contamination, 

which, if people frequented those areas, could be of health concern. 

3. Limited available data from other locations and air pathway considerations suggest that the 

military exercises in the LIA did not result in current contamination of residential soils with 

inorganic or explosive compounds at levels considered harmful. ATSDR arrives at this conclusion 

using a scientific evaluation of the available data. But again, data from other areas are limited in 

number, data for all potential contaminants of concern are not available, and no adequate 

surface soil data are available from the residential area itself. ATSDR nonetheless understands 

that community members remain concerned about residential soil exposures. 

4. Modeling described in the air pathway discussion has suggested that airborne transport of 

contaminants during past military exercises would not have been substantial enough to have 

affected soils in the island’s residential area. Sufficient historical data are not available to 

confirm this, nor will such data ever become available. Consequently, we cannot determine 

whether past exposures to explosives or other compounds in surface soil could have been heavy 

enough to increase a past risk of adverse health effects. 

9.7.2. Recommendations

1. Continue to restrict the LIA and other potentially contaminated military areas and continue 

environmental assessment and remediation activities to clear the way for public access.

2. To help address community concerns regarding residential soil, work with local residents to 

design sampling to identify residential surface soil quality issues, whether or not those surface 

soil issues relate to past military activities:

a. Focus initial sampling on areas identified as potential high-exposure areas, such as bare areas 

or child-use areas. 

b. To identify any possible differences in the top layer, initial sampling should analyze the top 

inch of soil separately from the rest of the 0–3 or 0–6 inch surface samples.

c. Perform a full range of analyses to identify all possible contaminants. 

d. Plan and conduct sample collection and analysis to ensure the results meet high data quality 

standards.

3. Although this sampling might provide inferences about past exposures for compounds stable 

over time, such as metals or other inorganic compounds, it will provide no definitive information 

on past surface composition and no information on past levels of compounds that react or 

degrade over time. 

4. ATSDR also recommends collection of representative soil samples as part of its evaluation of the 

terrestrial food chain pathway. See Chapter 5 of this report for details.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 172

9.8. Drinking Water Pathway

9.8.1. Conclusions

1. The available sampling data of Vieques storage tanks and representative drinking water taps

indicate that at the time of sampling, the public drinking water supplied via pipeline from Puerto 

Rico was acceptable to drink. This conclusion, however, is uncertain due to the limited number 

of samples and lack of additional rounds of confirmatory sampling. Public water supplies are 

tested regularly and have to meet water quality criteria. We have reviewed recent water quality 

reports indicating that lead levels have been a problem in the drinking water supply, although 

those problems appear to have been addressed now. Ongoing monitoring of the current 

pipeline source water and prompt action to address problems is required to ensure the supply 

meets drinking water standards.

2. Limited, late 1990s sampling data from public and private wells indicated that most of the wells 

are acceptable for occasional consumption, such as when the pipeline source is interrupted.33

Flow patterns preclude groundwater from the east (where most military operations occurred) 

affecting the public aquifer. And with the exception of one well, all groundwater contaminants 

were below ATSDR health screening values. But again, confidence in the conclusions is 

tempered by the limited number of sampling rounds, which might not have captured seasonal 

fluctuations in contaminant levels. Also, a lack of adequate historical data prevents ATSDR from 

making any conclusion about past public supply well exposures (i.e., the 1970s and 1980s). 

3. Although additional sampling might change the result, ATSDR confirms its previous conclusion 

that nitrate-nitrite levels in one private well would pose a health hazard, especially to children. 

Regardless of the source of this contamination, water from this well should not be consumed 

unless proven safe by further, comprehensive testing. 

4. No data are available to evaluate rainwater collection systems for past or present exposure 

potential to contaminants. Rainwater collection systems remain a potential exposure pathway.

5. Past military activities did affect groundwater under some specific military areas, but the 

affected groundwater is not currently used for drinking water.

9.8.2. Recommendations

1. Continue required monitoring of the public water supply source water and take prompt action 

to address any exceedances of drinking water standards. Repeat the 1999-2000 storage tank 

and residential tap sampling, including a wider selection of representative taps. This could 

confirm the conclusion that the present public water supply is acceptable to drink.

2. Conduct additional sampling of the wells still available for use during pipeline service 

interruptions. This too could confirm the safety of drinking water from these wells.

 

33 Although the “Sun Bay” public wells have been abandoned, to our knowledge the “B” public wells and the 

private wells can still supply drinking water.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 173

3. Determine whether people drink water from rainwater collection systems, and if so, test the 

collected water to evaluate its safety. Additionally, sample the sediment from these systems; 

the sample results might provide limited information about the water’s past quality.

4. Do not use groundwater beneath the LIA and other former military operations for drinking 

water; continue environmental assessment and remediation activities to identify and clean up 

impacted groundwater.

9.9. Final Summary

ATSDR conducted a thorough review of environmental, biological, and health outcome data from the 

Island of Vieques. We carefully considered the data and information from Puerto Rican and other 

scientists who spent considerable effort and time, sometimes at their own expense, to research 

environmental health issues in Vieques. We are grateful for their efforts. Nevertheless, as with any site 

that has such a long history of environmental investigations, those data have strengths and weaknesses 

that become important in public health decision-making. At times, the data can raise as many questions 

as they can provide answers. 

One such situation is mixtures. ATSDR recognizes the possibility that this report cannot address 

accurately the effects of mixtures and cumulative exposures on the health of Viequenses. Sometimes 

this is the result of a lack of data; other times it is a limitation of the science. ATSDR has published 

guidance for mixtures assessments (ATSDR 2004) and has some of the world’s experts on these subjects 

among our staff. But we recognize the continuing debate among scientists on these subjects and that no 

scientific consensus, or “best practice,” has yet emerged on how to assess these effects accurately.

Further, we are aware of the literature that examines the physical and psychological health effects 

stress can have on a community such as Vieques, given its six decades of military activities and lingering 

concern for the effects of those activities on the population’s health. Studies have shown that chronic 

stress is a risk factor in cardiac disease and contributes to the onset of autoimmune diseases. Chronic 

stress also is an important factor in premature aging.

Finally, as we stated at the outset of this report, ATSDR recognizes that Viequenses are concerned about 

the health of everyone who lives on their island. We hope the conclusions and recommendations in this 

report will raise public health awareness, increase the public’s well-being, and protect the health of all 

Viequenses.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | 174
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-1

Appendix A—Study Summaries 

Dramatic Increase in Radiation in Vieques................................................................................................A-3

Radioactivity in Vieques [trans.] ................................................................................................................A-5

Environmental Impact of Navy Activities in Vieques.................................................................................A-8

Heavy Metal Studies in Sediments from Gato and Anones Lagoons [trans.]..........................................A-11

Heavy Metals in the Impact Area Prevailing Vegetation, Vieques, Puerto Rico [trans.].........................A-13

Toxic Metals in the Vegetation of the Civilian Zone of Vieques, Puerto Rico [trans.].............................A-17

Trace Element Composition in Forage Samples from a Military Target Range, Three Agricultural Areas, 

and One Natural Area in Puerto Rico..................................................................................................A-21

Trace Elements Analysis in Forage Samples from a U.S. Navy Bombing Range (Vieques, Puerto Rico) .A-24

Evaluation of Heavy Metals in Agricultural Products of a Farm with Organic Practices in the Bo. Lujan 

Sector Destination of Vieques (Puerto Rico) [trans.]..........................................................................A-26

Determination of Arsenic (As), Cadmium (Cd), Chromium (Cr), Cobalt (Co) and Lead (Pb) in “Smooth 

Cayenne” Pineapple Fruit, Leaves Tissue and Soil Using Inductively Coupled Plasma Optical Emission 

Spectrometry (ICP-OES) ......................................................................................................................A-28

Herbivorous: Additional Evidence of Heavy Metal Mobilization through the Food Web.......................A-30

Draft Findings in Vieques, Puerto Rico (AKA Heavy Metals in Reefs Where Bombs Are) .......................A-32

Biomagnification of Carcinogenic Metals in Crab Tissue, Vieques, Puerto Rico......................................A-34

Research on the Physical and Chemical Conditions of Sea Grasses Thalassia testudium and Syringodium 

filiforme in Vieques [trans.].................................................................................................................A-37

Toxicological Study of Heavy Metals in Fish Populations at Vieques Island [trans.]...............................A-38

Radiological, Chemical, and Environmental Health Assessment of the Marine Resources of the Isla de 

Vieques Bombing Range, Bahia Salina del Sur, Puerto Rico ...............................................................A-40

Carcinogens Found in Marine Life in Island of Vieques in Puerto Rico ...................................................A-44

Contamination Produced by Explosives and Explosive Residues in Vieques [trans.]..............................A-45

Vieques Litigation Support: Explosives Analyses of Water and Soil Samples Taken on Vieques Island, 

Puerto Rico..........................................................................................................................................A-47

Vibroacoustic Disease Induced by Long-Term Exposure to Sonic Booms ...............................................A-50

Scientific Investigation of Toxic Metals Present in the Biological Terrain of Vieques Children and Adults 

and Their Effects on Nutrient Minerals [trans.] ..................................................................................A-52

Heavy Metal Exposure and Disease in the Proximity of a Military Base .................................................A-55

Mercury Contamination in Reproductive Age Women in a Caribbean island: Vieques..........................A-57
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-2

Arsenic Detected in Urine, Nails, and Hair Study (Exact title not available)............................................A-59

Executive Summary of the Prevalence of Heavy Metals in Vieques........................................................A-61

Title not determined................................................................................................................................A-63

Cancer Incidence and Mortality in Vieques 1990–2001 ..........................................................................A-64

Exploratory study of health and other conditions in Vieques.................................................................A-66

Incidence and Mortality of Cancer in Vieques 1990–2004......................................................................A-67

Ex-USS Killen Site Investigation and Biological Characterization, Vieques Island, Naval Station Roosevelt 

Roads, Puerto Rico ..............................................................................................................................A-69

A Tale of Germs, Storms, and Bombs: Geomorphology and Coral Assemblage Structure at Vieques 

(Puerto Rico) Compared to St. Croix (U.S. Virgin Islands) ...................................................................A-70

Field Data Summary, Vieques Fish Assessment, Vieques, Puerto Rico ...................................................A-71

An Ecological Characterization of the Marine Resources of Vieques, Puerto Rico Part II: Field Studies of 

Habitats, Nutrients, Contaminants, Fish, and Benthic Communities..................................................A-72
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-3

Category: Environmental Data – Radiation

Date of Publication: November 9, 2001

Title: Dramatic Increase in Radiation in Vieques

Author(s): Frankie Jimenez

Affiliation: Committee for the Rescue and Development of 

Vieques (CRDV)

Publication Status: Press Release

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Air Pathway 

Evaluation)

Study Findings

In 2001, after two rounds of bombing in Vieques, radiation sampling resulted in these findings:

Table A-1. Radiation sampling in Vieques, 2001

Date Sampling Location Radiation Level

June 2001

Civilian areas 

Yayi Beach (near bombing range)

No increase

60% increase

SeptemberOctober 2001

Esperanza Beach (civilian area, south coast)

Main town (Isabel II, north coast)

248% increase

225% increase

The authors attributed the radiation increase to soil dispersion contaminated by past use of depleted 

uranium (DU) penetrators at the Live Impact Area (LIA). The press release did not indicate how levels of 

radiation were measured, what types of radiation were measured, or the actual amounts of radiation 

detected.

The press release did, however, condemn future bombing exercises planned for November–December 

2001.

How ATSDR Addressed the Study Findings

In 2002, ATSDR contacted the Committee for the Rescue and Development of Vieques (CRDV) to learn 

more about this sampling effort, but did not receive a response. The allegation that radiation levels 

increased on Vieques during military training exercises could not be confirmed. No public health 

decisions could be made based on a reported 248% increase in radiation levels without data. The more 

important indicator of exposure is the actual level of radiation, not the relative increase. No 

confirmation of statements made in the press release could be obtained. Nonetheless, in Section V.D of 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-4

the PHA’s Air Pathway Evaluation, ATSDR used established background levels to investigate the public 

health implications of the reported radiation increase. 

To estimate the effect of a reported 248% dose increase, ATSDR used data collected by the Nuclear 

Regulatory Commission (NRC) to establish background radiation levels. In June 2000, the NRC recorded 

radiation dose rate measurements at 29 locations in Vieques residential areas using a Ludlum Model 19 

microR meter. These observations were collected at a distance of 1 meter above ground surface. The 

29-measurement average exposure rate was 4 microroentgens per hour (μR/hour)—approximately 

equal to 4 microrem per hour (μrem/hour). ATSDR assumed this dose rate represented external 

radiation background levels in the Vieques residential areas. If the CRDV data were based on similar 

dose rate observations, a 248% increase in radiation would imply that radiation levels increased from 4 

μrem/hour to 14 μrem/hour, or a net increase above background of 10 μrem/hour. Assuming this 

increase above background occurred 24 hours per day for 90 days per year (i.e., the maximum amount 

of time the Navy could conduct military training exercises on Vieques), the overall increase in radiation 

dose for the year would be 22 mrem—a level well below ATSDR’s chronic minimal risk level (MRL) for 

ionizing radiation. The MRL is defined as an increase in ionizing radiation dose of 100 mrem above 

background per year. Thus given these parameters, ATSDR does not consider a 248% increase indicates 

radiation exposures at levels of concern presuming an exposure rate of 4 μrem/hour. 

In fact, ATSDR noted that the levels of radiation measured in the NRC study appear to be well within 

background levels observed throughout the United States. And a non-CRDV press release (Fellowship of 

Reconciliation 2001) announced that the highest level of radiation measured during the recent survey 

on Vieques was 18 μR/hour—approximately equal to 18 μrem/hour. These levels are comparable to 

survey readings collected elsewhere in the United States; they are considerably lower than background 

measurements from many areas at elevations of several thousand feet such as Denver, Colorado. Due to 

its higher elevation, Denver would be expected to have higher-than-average radiation levels.

As part of the agency’s analysis of data, ATSDR again requested more information on the study. In 

response to ATSDR’s request, the report “Radioactivity in Vieques” was received on August 5, 2009.

Reference

Fellowship of Reconciliation. 2001. Vieques issue brief: environmental impacts of navy training; 

November 2001.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-5

Category: Environmental Data – Radiation

Date of Publication: circa 2000

Title: Radioactividad en Vieques 

Radioactivity in Vieques [trans.]

Author(s): Frankie Jimenez

Affiliation: Committee for the Rescue and Development of 

Vieques (CRDV)

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

From October 7, 1999 to February 3, 2000, radiation sampling was conducted on the Live Impact Area 

(LIA). The investigator conducted the sampling in response to the U.S. Navy’s accidental use of depleted 

uranium projectiles on February 19, 1999. The investigator took gamma radiation measurements from 

around the targets (e.g., tanks and aircraft), from the roads leading to the targets, and from areas where 

former targets were buried. Yayí Beach was measured as the background location. 

According to the investigator’s report, samples were collected with an instrument “manufactured by the 

Nuclear Research Corporation.” The report provided no further sampling device information nor did the 

report list actual amounts of radiation detected at other locations. It provided instead the percent 

increase above readings at Yayí Beach. Lastly, the report did not specify the averaging time for individual 

measurements. Thus whether the findings were based on instantaneous peak radiation levels or 

sustained averages is unclear.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-6

Table A-2. Vieques LIA radiation sampling, 1999–2000

Sampling Location Radiation Level

Yayí Beach (background location) 7 μR/hr

Mayor of Cataño’s camp 30% increase

Several aircraft behind the “Pro Vieques” camp 50% increase in front of the planes, “normal” 

away from the planes

Tank just before the mountain 200% increase

Tank at the top of the mountain 100% increase

Roads leading to the targets 100% increase, “normal” immediately beyond 

the roads

Tanks near the Monte David camp 50% increase

Slope of the mountain near the Monte David camp 220% increase

Tanks near Salina Sur Beach 100% increase

μR/hr = microroentgens per hour

At the beginning of the article, the investigator noted that radiation levels in the LIA were “over 500% 

higher than normal.” But 220% was the highest percent increase listed. Because certain areas indicated 

“above-normal” radioactivity, the investigator concluded that radioactive material was present on and 

around the targets as well as under the surface (e.g., roads and burial grounds). After completing some 

sampling, on January 19, 2000, the investigator filed a complaint with the Nuclear Regulatory 

Commission (NRC). That complaint might have triggered the NRC study reviewed in the PHA’s Air 

Pathway Evaluation.

How ATSDR Addressed the Study Findings

ATSDR received this report on August 5, 2009. Because this report—like a contemporary press release 

entitled Dramatic Increase in Radiation in Vieques—lacked an actual radiation level reading, ATSDR 

investigated the public health implications of the reported increase in radiation using the same 

approach as presented in Section V.D of the PHA’s Air Pathway Evaluation. A 220% increase in radiation 

would imply that radiation levels increased from the background of 7 μr/hour (approximately equal to 7 

microrem per hour [μrem/hour]) to 22 μrem/hour, or a net increase above background of 

15 μrem/hour. Assuming this increase above background occurred 24 hours per day, 365 days per year, 

the overall increase in radiation dose for the year was 131 mrem. ATSDR’s chronic minimal risk level 

(MRL) for ionizing radiation is defined as an increase in ionizing radiation dose of 100 mrem above 

background per year. Even given that this estimated dose exceeded ATSDR’s MRL, the calculation did 

not take into account individual occupancy. That is, for the MRL to be exceeded, a person would have to 

find the elevated radiation-level location and remain there 24 hours per day for an entire year. A more 

realistic—yet still unlikely—scenario is for a person to remain at the location 4 hours per day over the 

course of a year. This would result in an increased radiological dose of 20 mrem for the year. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-7

Thus with respect to the actual method used to detect the radiation, the information supplied is of 

limited use: the background range was not specified. Typically, gamma radiation measurements will vary 

by 3 to 5 μR/h. As the author stated, the measured background was 7 μR/h, which ATSDR believes could 

vary up to 11 or 12 μR/h. Such a meter variation could also account for the large percentages observed. 

For example, if the average were 7 μR/h, an increase in 3 μR/h would represent a 50% increase.

Further, although depleted uranium (DU) is radioactive, its gamma radiation emission is low. It would 

not add to the ambient background radiation detectable by the type of radiation meter used in this 

study. In fact, the United Nations estimated that DU radiation is so weak it would be shielded by the soil 

in which it was buried.34 Thus ATSDR believes the reported DU radiation was in error.

 

34 World Health Organization (2001). Report of the World Health Organization. Depleted uranium mission to 

Kosovo. Available online at 

http://www.who.int/ionizing_radiation/pub_meet/en/Report_WHO_depleted_uranium_Eng.pdf [accessed 2011 

June 13].
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-8

Category: Environmental Data – Soil, Sediment, and Water

Date of Publication: July 11, 2000

Title: Environmental Impact of Navy Activities in Vieques

Author(s): N García Martínez, AM López, M Soto, T Garcia, S 

Rosado, B Berríos 

Affiliation: Servicios Científicos y Técnicos

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Soil Pathway 

Evaluation)

Study Findings

From May 1999 to April 2000, personnel from Servicios Científicos y Técnicos, Inc. collected and 

analyzed soil, sediment, and surface water samples from 55 Vieques locations. Their purpose was to 

determine levels of metals and other inorganic compounds in the Vieques ecosystem. Forty-four 

samples were collected from the LIA: specifically, areas of direct impact, target areas, and nearby areas. 

Five were collected from the Punta Este Conservation Zone, and six were taken from the residential 

area. Eleven water samples were collected from lagoons in the LIA, from Carrucho Beach, and from the 

Punta Este Conservation Zone. The sample analysis included highest and second highest concentrations:

Table A-3. Water samples from LIA lagoons

Chemical Highest 

Concentration (ppm)

Type of 

Sample

2nd Highest 

Concentration (ppm) Type of Sample

Aluminum 24,500 soil 23,600 soil

Ammonia 50.1 sediment 46.8 soil

Arsenic 20.2 soil 16.4 soil

Barium 1,170 soil 1,100 soil

Cadmium 31.3 soil 27.4 soil

Chromium 40.2 sediment 31.9 soil

Cobalt 26.4 soil 21.4 soil

Copper 501 soil 313 soil

Iron 67,900 soil 51,400 sediment

Lead 138 sediment 75.4 soil

Manganese 1,111 soil 811 soil

Mercury 4.21 sediment 0.329 sediment

Nickel 68.7 soil 32.9 sediment
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-9

Chemical Highest 

Concentration (ppm)

Type of 

Sample

2nd Highest 

Concentration (ppm) Type of Sample

Nitrates plus Nitrites 50.8 sediment 30.2 soil

Phosphorous 40.4 soil 16 sediment

Selenium 1.48 sediment 1.34 sediment

Silver 0.625 soil 0.526 sediment

Sulfate 8,590 NA 8,380 NA

Tin 38.7 surface water NA NA

Vanadium 178 soil 164 soil

Zinc 872 soil 325 soil

NA = not available

ppm = parts per million

The authors reported that higher levels of metals and other substances were in the sediment, soil, and 

water samples collected from the LIA as opposed to samples collected from the eastside territory and 

from the civilian zone. LIA zinc and copper concentrations were higher than those USGS reported in 

1973. The authors recommended additional environmental sampling in the civilian area and western 

portion of Vieques, as well as biomonitoring samples from Vieques residents.

How ATSDR Addressed the Study Findings

In a statistical comparison with other LIA data, these data show nine of the 20 chemicals were 

significantly different (higher, p <0.05): ammonia, barium, cadmium, copper, lead, mercury, nickel, 

nitrate/nitrite, and zinc. This does not imply any data discrepancy; it simply means that using only the 

highest and second highest detections rather than the complete dataset would skew any results. 

Therefore, these data were not used in the statistical analyses to evaluate general soil characteristics. 

They were, however, used to form the following conclusions during the public health evaluations in the 

PHA’s Soil Pathway Evaluation (see Section IV in the Soil Pathway Evaluation):

 During the public health assessment process, all available soil sampling data were considered, 

including the data presented in the Servicios Científicos y Técnicos report.

 To evaluate human exposures, ATSDR compiled roughly 600 soil/sediment samples (for a soil 

sampling summary, see pages 13–15 of the PHA).

 Vieques residents are not currently exposed to harmful levels of chemicals in the soil.

 Although in the past, Navy training activities elevated the levels of some metals in the soil on 

the former LIA, those levels remain too low to be of health concern.

 Protestors who lived on the LIA for a year (1999–2000) endured the longest exposure to LIA soil 

contaminants. ATSDR analyzed the soil data collected by Servicios Científicos y Técnicos—
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-10

together with Navy data—from areas where the protestors lived. ATSDR determined that the 

protestors were not exposed to harmful levels of chemicals in the soil.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-11

Category: Environmental Data – Sediment

Date of Publication: 2002

Title: Metales pesados en sedimentos de las Lagunas Gato y 

Anones. Heavy Metal Studies in Sediments from Gato and 

Anones Lagoons [trans.] 

Author(s): Arturo Massol-Deyá and Elba Diáz

Affiliation: Casa Pueblo de Adjuntas; University of Puerto Rico, 

Mayaguez Campus

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

Gato and Anones lagoons are on the western side of the Live Impact Area (LIA), near the Surface Impact 

Area (SIA). On February 12, 2000, to characterize heavy metal contamination, a sediment sample was 

collected from each lagoon. The samples were taken only from the lagoon dry areas. 

The samples were 50 and 30 centimeters deep and were analyzed in 10- and 5- centimeter intervals 

(Gato and Anones, respectively). The authors reported that with respect to depth, the metals were 

almost homogeneously distributed. No significant differences appeared in the concentrations of heavy 

metals at different depths, nor between the lagoons. The authors noted that the “results display a high 

degree of mixture in the sediments down to at least 50 cm (20 inches) caused primarily by the intensity 

of bomb impacts in the area.”

The authors reported sampling results in a bar chart. An approximate interpretation of their data is 

presented below.

Table A-4. Sediment samples from Gato and Anones Lagoons

mg/kg

Copper Cobalt Cadmium Lead Nickel Chromium Manganese

Gato 40–60 60–100 60–100 100–130 60–125 300–500 900–1750

Anones 40–85 75–110 75–110 90–140 75–100 200–250 600–1000

No health guideline was cited.

How ATSDR Addressed the Study Findings

ATSDR obtained this study in July 2009, and reviewed the data as part of its evaluation of Vieques. 

These data were collected from the former LIA—a restricted area. Thus no one is now continuously 

exposed to these chemicals. The longest potential exposure occurred from April 1999 to May 2000, 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-12

when protestors occupied the LIA. As reported by Massol-Deyá and Diáz (2002), the maximum 

concentrations of cobalt, cadmium, lead, nickel, chromium, and manganese were higher than the 

concentrations evaluated in the 2003 Soil Pathway Evaluation. And when matched with health-based 

comparison values, the cadmium and chromium concentrations were higher as well. As noted, however, 

access remains restricted to the former LIA (including Gato and Anones lagoons). 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-13

Category: Environmental Data – Plants 

Date of Publication: April 10, 2000

Title: Metales pesados en la vegetación dominante del área de 

impacto de Vieques, Puerto Rico. 

Heavy Metals in the Impact Area Prevailing Vegetation, 

Vieques, Puerto Rico [trans.]

Author(s): Arturo Massol-Deyá and Elba Diáz

Affiliation: Casa Pueblo de Adjuntas and University of Puerto 

Rico, Mayagüez

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Soil Pathway 

Evaluation)

Study Findings

In February and March 2000, researchers from Casa Pueblo and the University of Puerto Rico’s Recinto 

Universitario de Mayagűez (RUM), sampled vegetation for heavy metals in the Live Impact Area (LIA)—

specifically, Carrucho Beach, Monte David, and Gato and Icacos Lagoons. Reference populations of the 

same species were also collected in Bosque Seco de Guánica and RUM Alzamora Ranch. Researchers 

sampled the following plants:

Urochloa maxima (root and stem), 

Sporobolus virginicus (root and stem), 

Syringodium filiform (stem), 

Ipomoea violaceae (fruit), 

Faidherbia albida (stem), and 

Calotropis procera (leaves). 

The average concentrations are presented in Table A-5.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-14

Table A-5. LIA vegetation sample results

Average concentrations (μg/g)

Lead Cobalt Nickel Manganese Chromium Cadmium Copper Magnesium Zinc

Playa Carrucho

S. filiforme 33.32 29.60 28.66 58.23 2.78 2.78 30.48 9929.14 106.24

Sargazo 22.69 130.46 28.23 169.07 7.36 2.83 28.27 17914.70 187.54

Monte David

U. maxima 

(root) 12.85 63.66 14.19 115.44 21.04 2.89 17.10 2550.16 65.78

U. maxima 

(stem) 10.25 48.65 5.08 135.02 5.99 1.57 4.03 1667.61 42.98

C. procera 

(leaves) 30.05 68.40 18.08 287.94 12.68 3.11 4.63 11401.98 112.47

A. farnesiana 

(stem) 8.13 10.15 5.33 18.27 2.86 ND 4.04 2095.67 15.14

Laguna Icacos

Aquatic plant 2.69 36.31 29.31 1740.42 42.14 4.63 12.93 - 68.97

Laguna Gato

I. violaceae 

(fruit) 32.61 25.75 7.64 40.31 1.17 ND 9.39 1867.95 50.86

S. virginicus 

(root) 17.17 68.61 78.26 882.35 182.62 1.18 10.36 5135.36 73.20

S. virginicus 

(stem) 30.45 34.81 ND 670.57 5.32 ND ND 1553.96 24.40

S. 

pyramidatus 

(root)

18.77 22.91 7.14 156.23 15.77 2.25 9.02 4450.16 45.06

S. 

pyramidatus 

(stem)

12.19 2.73 1.25 31.75 3.03 ND ND 2931.47 15.60

Bosque Seco de Guanica and Alzamora Ranch (reference populations)

C. procera 

(leaves) 1.29 2.59 5.17 17.85 9.31 1.03 5.69 - 19.91

S. filiforme 

(stem) 5.57 4.19 14.64 251.44 27.93 2.79 15.39 - 59.31

S. virginicus 

(stem) 0.60 3.11 5.36 7.54 7.35 0.79 2.76 - 14.83

U. maxima 

(root) ND 6.89 19.95 78.61 23.75 0.80 14.52 - 75.77
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-15

U. maxima 

(stem) ND 4.69 10.50 35.19 12.24 0.60 12.93 - 59.53

ND = not detected

The authors reported that in Vieques vegetation, concentrations of heavy metals such as lead, cobalt, 

and manganese were significantly higher than concentrations detected in the reference locations. The 

authors concluded that with the levels detected, if people were to eat these plants they would be 

exposed to critically hazardous doses. The authors recommended remediation to reduce the transport 

of chemicals from the LIA to the residential areas.

How ATSDR and the Puerto Rico Department of Agriculture Addressed the Study Findings

This and other studies by the same researchers reported metals in plants and livestock. Consequently, 

on August 7, 2001, the Puerto Rico Department of Agriculture placed an embargo on Vieques produce 

and livestock. The Puerto Rico Department of Agriculture, in cooperation with the Farmers Association 

of Puerto Rico, then sampled grass, fruit-bearing trees, and bovine livestock for cadmium, cobalt, 

copper, lead, manganese, and nickel. Samples were taken from Monte Carmelo, Martineau, Monte 

Santo, Esperanza, Lujan, Gubeo, and western Vieques. Sample analysis resulted in the conclusion that 

Vieques agricultural products were in fact suitable for consumption and did not contain toxic levels of 

the named contaminants (Department of Agriculture 2001). Because government and Farmer’s 

Association researchers could not duplicate Dr. Massol’s results, the embargo was lifted (El Nuevo Día 

2001).

As part of the previous public health assessment, ATSDR requested that an agronomist with the U.S. 

Department of Agriculture (USDA) independently review the Casa Pueblo and RUM studies. The 

agronomist determined that although the studies provided evidence of heavy metals accumulation in 

plants, the studies’ limitations prevented an estimation of human exposure dose. The agronomist 

further concluded that

Many of the species sampled in this study were not eaten, and when edible 

species were sampled, the edible portions were not sampled. Human exposures

from locally grown foods are best estimated from the edible portions of the 

food source. In general, the edible portions of plants are less likely to 

accumulate metals from soil because of normal plant processes (i. e., 

physiological barriers that prevent contaminants from reaching the tops of 

plants) (ATSDR 2001).

Additionally, the studies lacked standard reference materials to demonstrate that the results were 

accurate and lacked background corrections for lead, cobalt, nickel, and cadmium to eliminate the effect 

of light scattering by non-element materials in the samples.

The metals analysis also did not indicate whether the metals were bioavailable. This is important 

because vegetation samples include both contaminants taken up by the plant and soil particles from the 

growing media. Thus even with a thorough washing, small soil particles will adhere to the plant 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-16

materials and can actually carry more contaminants than those taken up by the plant from the soil 

(ATSDR 2001). When the external soil contamination is ingested, the chemicals bound to soil are not 

usually in a form the body can absorb. While methods are available to determine how much of a 

chemical concentration is adhered as soil and how much is in the plant tissue, the researchers here did 

not use them. 

Thus ATSDR could neither quantify human exposures nor draw any health conclusions about whether 

consuming plants grown in Vieques would result in harmful health effects. As part of its evaluation, 

ATSDR recommended additional sampling of subsistence produce.

References

ATSDR. 2001. Summary Report for the ATSDR Expert Panel Meeting on Tribal Exposures to 

Environmental Contaminants in Plants. Atlanta: Division of Health Assessment and Consultation; 2001 

March 23.

Department of Agriculture. 2001. Letter from Luis Colón to the Undersecretary of Agriculture concerning 

heavy metal tests on Vieques bovine livestock. 2001 October 17.

El Nuevo Día. 2001. They declare suitable the agricultural products in Vieques. 2001 December 13.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-17

Category: Environmental Data - Plants

Date of Publication: January 10, 2001

Title: Metales tóxicos en la vegetación de la zona civil de 

Vieques, Puerto Rico. Toxic Metals in the Vegetation of 

the Civilian Zone of Vieques, Puerto Rico [trans.]

Author(s): Arturo Massol-Deyá and Elba Diáz

Affiliation: Casa Pueblo de Adjuntas and University of Puerto 

Rico, Mayagüez

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Soil Pathway 

Evaluation)

Study Findings

Researchers from Casa Pueblo and University of Puerto Rico’s Recinto Universitario de Mayagűez (RUM) 

randomly collected agricultural and common vegetation from three sites within 1) a Vieques residential 

section, 2) an agricultural area in Monte Carmelo as well as a section of Monte Carmelo that borders 

Camp Garcia, and 3) an agricultural farm in Barrio Monte Santo, Gobeo sector. The ensuing paper, 

however, limited its discussion to the two farms sampled in the civilian area of Vieques and focused its 

conclusions and recommendations on plants grown for an agricultural economy. 

The study reported that all metals (cadmium, cobalt, copper, lead, and manganese) were found at toxic 

levels. Lead and cadmium had the highest absorption rates. Sampling included leaves and stems of 

pumpkin, pepper, pigeon peas, pineapple, and yucca. Only guamá and mangoes showed acceptable 

metals levels.

The study reported the following average concentrations found in plant stems and leaves. It did not 

report concentrations in the edible portions of the plants sampled (See Table A-6).

The authors concluded that the highest concentrations of metals were found in plants that had shallow 

roots—where higher contamination levels would be expected to be found in the soil— and plants 

requiring higher watering rates (more access to soil contamination). 

Study recommendations included

 Permanent cessation of contamination-causing activities.

 A moratorium on consumption of plants grown in Vieques and compensation for farmers.

 Preventative actions for children who are more sensitive to toxins.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-18

How ATSDR and the Puerto Rico Department of Agriculture Addressed the Study Findings

Because this and other studies by the same researchers reported metals in plants (Massol 2000) and 

livestock (Massol 2001), the Puerto Rico Department of Agriculture on August 7, 2001, placed an 

embargo on Vieques produce and livestock. The Puerto Rico Department of Agriculture, in cooperation 

with the Farmers Association of Puerto Rico, sampled grass, fruit-bearing trees, and bovine livestock 

from Monte Carmelo, Martineau, Monte Santo, Esperanza, Lujan, Gubeo, and western Vieques for 

cadmium, cobalt, copper, lead, manganese, and nickel. The Department of Agriculture and the Farmer’s 

Association concluded that the agricultural products from Vieques were suitable for consumption and 

did not contain toxic levels of the named contaminants (Department of Agriculture 2001). When the 

Department of Agriculture and the Farmer’s Association could not duplicate Dr. Massol’s results, the 

embargo was lifted (El Nuevo Día 2001).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-19

Table A-6. Vegetation samples

Average Concentrations (μg/g dry weight)

Lead Cobalt Nickel Manganese Cadmium Copper

Monte Carmelo, agricultural area

C. procera (leaves) 62.16 15.54 20.76 469.58 4.87 28.78

A. farnesiana (leaves) 11.77 7.57 5.81 338.81 1.79 22.90

A. famesiana (stem) 13.04 7.47 5.14 33.26 1.10 14.70

U. maxima (leaves) 8.97 15.24 6.50 29.80 1.57 14.79

Pumpkin (leaves) 42.23 22.52 22.96 97.69 7.94 32.57

Pepper (leaves) 22.64 21.45 9.07 68.53 3.91 21.98

Pepper (stems) 11.85 24.55 12.31 21.66 5.73 41.68

Pigeon Peas (leaves) 10.59 14.81 10.28 193.36 2.72 15.44

Pigeon Peas (stem) 4.80 16.06 4.00 40.38 1.38 8.77

Bo. Monte Santo. Gobeo Sector

Pepper (leaves) 39.52 6.04 12.90 30.48 2.59 34.11

Pepper (stem) 44.65 8.93 5.52 11.50 2.55 27.66

Mango (leaves) 12.40 3.51 3.00 372.90 0.75 6.26

Yucca (leaves) 29.23 10.22 3.49 104.46 2.23 39.27

Guama (leaves) 7.80 3.81 2.07 155.11 0.94 13.02

Banana (leaves) 29.99 6.06 2.25 507.53 0.64 16.57

Pigeon Pea (leaves) 49.14 6.03 6.65 74.60 1.10 25.81

Pigeon Pea (stem) 63.17 14.58 11.35 37.58 3.57 22.67

Pumpkin (leaves) 17.02 9.86 13.99 110.49 3.58 33.71

U. maxima (leaves) 8.58 2.75 4.79 57.97 0.69 11.48

Pineapple (leaves) 40.46 6.78 14.48 98.85 2.78 17.64

Quenepa (leaves) 18.68 8.33 5.25 34.78 1.06 14.61

As part of the 2001 public health assessment, ATSDR requested independent review of the study by an 

agronomist with the U.S. Department of Agriculture (USDA). That agronomist determined that although 

the studies provided evidence that heavy metal accumulation in plants, the study’s limitations 

prevented estimation of a human exposure dose. The agronomist further concluded:

Many of the species sampled in this study are not eaten, and when edible 

species were sampled, the edible portions were not. Human exposures from 

locally grown foods are best estimated from the edible portions of the food 

source. In general, the edible portions of plants are less likely to accumulate 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-20

metals from soil because of normal plant processes (e.g., physiological barriers 

that prevent contaminants from getting to the tops of plants) (ATSDR 2001).

The study lacked the use of standard reference materials to demonstrate that the results were accurate. 

The study also lacked background corrections for lead, cobalt, nickel, and cadmium to eliminate the 

effect of light scattering by non-element materials in the samples.

The metals analysis did not indicate whether the metals were bioavailable. This is important because 

samples of vegetation include both contaminants taken up by the plant and soil particles from the 

growing media. Even with a thorough washing, small soil particles will adhere to the plant materials, and 

can actually carry more contaminants than those the plant takes up from the soil (ATSDR 2001). When 

the external soil contamination is ingested, the chemicals bound to soil are not usually in a form that the 

body can absorb. While methods are available to determine how much of a chemical concentration 

adheres as soil and how much is in the plant tissue, the researchers here did not employ such methods. 

Because of these factors, ATSDR could neither quantify human exposures nor draw any health 

conclusions regarding whether consuming plants grown in Vieques would result in harmful health 

effects. As part of its evaluation, ATSDR recommended additional sampling of subsistence produce.

References

ATSDR. 2001. Summary Report for the ATSDR Expert Panel Meeting on Tribal Exposures to 

Environmental Contaminants in Plants. Division of Health Assessment and Consultation; Atlanta, 

Georgia. March 23, 2001.

Department of Agriculture. 2001. Letter from Luis Colón to the Undersecretary of Agriculture concerning 

heavy metal tests on Vieques bovine livestock. October 17, 2001.

El Nuevo Día. 2001. They declare suitable the agricultural products in Vieques. December 13, 2001.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-21

Category: Environmental Data – Plants 

Date of Publication: 2003

Title: Trace Element Composition in Forage Samples from a 

Military Target Range, Three Agricultural Areas, and One 

Natural Area in Puerto Rico

Author(s): Elba Diáz and Arturo Massol-Deyá

Affiliation: University of Puerto Rico, Mayagűez

Publication Status: Caribbean Journal of Science 2003;39(2):215–220 

Peer Review Status: Peer reviewed

Cited Previously by ATSDR: No

Study Findings

This paper discusses the same data that the authors published in April 10, 2000 – plant samples 

collected February and March 2000 and analyzed for heavy metals. The paper compares concentrations 

found on Vieques with concentrations detected on the main island of Puerto Rico. The 2000 sampling 

included plant stems and leaves, but it did not include the edible portions of the plants sampled. This 

peer-reviewed publication did, however, provide more information on sampling, preparation, and 

analytical techniques than did the April 2000 report.

In addition to the 2000 sampling data, this paper included new samples of C. cajan (pigeon peas) leaves 

and fruit taken August 18, 2001 and discussed the ratio of contamination detected in the fruit to 

contamination detected in the leaves. 

In Table 1 of the study, leaves and stems of four plant species were compared. When these findings 

were compared with samples from mainland Puerto Rico, the Vieques plant samples contained more 

lead, cobalt, and manganese, but less chromium and copper. For nickel and cadmium, results were 

mixed. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-22

Table 2 of the study compared leaves and stems of two plant species (pigeon peas and squash). As in 

Table 1, the Vieques samples had more lead and cobalt, but these two samples contained more 

cadmium and copper and less nickel and manganese.

Both sample sets showed that the Vieques plants contained more lead and cobalt. For the other metals, 

results were mixed depending on plant species. 

Table 3 of the study compares concentrations detected in pigeon pea fruit and leaf samples collected 

August 18, 2001. For some metals, higher concentrations were found in the fruit (zinc, nickel, cadmium 

and cobalt). For other metals (i.e., copper and lead), higher concentrations were found in the leaves.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-23

How ATSDR Addressed the Study Findings

ATSDR obtained this study in May 2009. Because pigeon peas are a species Vieques residents eat, ATSDR 

has undertaken a review of the new pigeon pea data as part of its analysis of Vieques data (see Chapter 

5). 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-24

Category: Environmental Data – Plants 

Date of Publication: August 14, 2005

Title: Trace Elements Analysis in Forage Samples from a U.S. 

Navy Bombing Range (Vieques, Puerto Rico)

Author(s): Arturo Massol-Deyá, Dustin Pérez, Ernie Pérez, 

Manuel Berrios, and Elba Díaz

Affiliation: University of Puerto Rico

Publication Status: Int J Environ Res Public Health 2005;2(2):263–266

Peer Review Status: Peer reviewed

Cited Previously by ATSDR: No

Study Findings

This paper discussed the same data the authors published in April 10, 2000, and 2003 – plant samples 

collected February and March 2000 and analyzed for heavy metals. The authors note that “distinctive 

profiles are observed within the studied species thus reflecting differences in their physiological 

properties.”

In addition to the 2000 sampling data, this paper included new samples of Syringodium filiforme

(Manatee grass) taken from the Atlantic Fleet Weapons Training Facilities (AFWTF) in 2004 and from 

Guánica State Forest in 2003 and 2004. Concentrations of heavy metals were higher at AFWTF. The 

authors advanced the hypothesis of bioaccumulation through the food chain: manatee grass to 

crustaceans and fish to humans. A similar food chain scenario was presented for migratory birds.

The authors evaluated temporal variations of the S. filiforme samples. Table 2 of their study shows 

heavy metal concentrations in 2004 (after bombing activities stopped) were approximately 1⁄2 the 

concentration levels found in 2000 (when the bombing range was active). Similar results were found in 

the control population—plants from Guánica State Forest located approximately 120 miles from the 

bombing range. 

Although not specifically stated by the authors, their data pointed out that “safe concentrations” 

detected in one species do not imply that other plant species have the same physiological properties 

and are also safe for consumption. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-25

How ATSDR Addressed the Study Findings:

Manatee grass is not a species Vieques residents eat. These data might provide ecologically important 

information, but they are not directly relevant to evaluating human health. ATSDR has recommended 

additional sampling of subsistence produce.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-26

Category: Environmental Data - Plants

Date of Publication: January 2008

Title: Evaluación de Metales Pesados en Productos Agrícolas de 

una Finca con Prácticas Orgánicas en el Bo. Luján Sector 

Destino de Vieques (Puerto Rico).

Evaluation of Heavy Metals in Agricultural Products of a 

Farm with Organic Practices in the Bo. Lujan Sector 

Destination of Vieques (Puerto Rico) [trans.]

Author(s): Elba Diaz de Osborne, Pablo Acevedo-Acevedo, and 

Arturo Massol-Deyá

Affiliation: University of Puerto Rico

Publication Status: Self-published

Peer Review Status: None

Cited by Previously ATSDR: No

Study Findings

In January 2008, researchers visited an organic farm in Vieques and collected leaves from cilantro, 

spinach, beans, peppers, and papaya plants. The researchers also analyzed for cadmium, chromium, 

copper, and lead. The researchers selected an organic farm because they believed the soil would be 

representative of naturally occurring soil and local airborne contamination. The researchers found 

concentrations of lead and cadmium in the Vieques vegetation significantly higher than concentrations 

detected in the reference plants in Mayagűez, a town on the western end of Puerto Rico, approximately 

120 miles from Vieques. 

Table A-7. Heavy metal levels in vegetation and health guideline from 1999 study

mg/kg, dry weight

Cadmium Chromium Copper Lead

Health Guideline cited in 

Study* 1.0 None given None given None given

Vieques 0.52 – 19.50 0.98-2.69 30.18 – 112.48 3.43 – 16.43

Mayagűez 0.74 – 1.70 No samples 44.05 – 54.24 1.88 – 5.10

*Food, Safety & Health of the European Union (1999)
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-27

Using these data, the researchers demanded that

1. The Navy compensate Vieques residents for the impact on agricultural activities: contaminated 

soil from Navy activities was windborne to the civilian areas of Vieques where it was taken up by 

agricultural plants.

2. Cleanup of the Live Impact Area (LIA) should include not only unexploded bombs, but

contaminated soil as well: winds still blow contaminated soil toward the civilian area.

3. Cleanup of the Live Impact Area (LIA) should include removal of unexploded bombs in the sea 

adjacent to Vieques.

4. The Puerto Rico Environmental Quality Board should deny the Navy’s application for a waiver to 

conduct open burning of vegetation: plants have taken up contamination in the soil, and burning 

plants would release that contamination to the air where it would ultimately reach Vieques 

residents.

How ATSDR Addressed the Study Findings

ATSDR requested and received this study from the author in October 2008. ATSDR found the 

concentrations, as reported, would be harmful to humans. Thus ATSDR consulted with the U.S. 

Department of Agriculture (USDA) about the study (Rufus Chaney, USDA, personal communication, 

October 28–30, 2008). USDA noted that

 The reported levels of copper would be phytotoxic to the plants.

 The soil might have been experimentally enhanced to increase metal uptake. The 

measurements reported were consistent with plants grown in soils artificially enhanced to 

increase metal uptake in plants.

Because of the limitations of this study, ATSDR recommended additional sampling of subsistence 

produce (see Chapter 5, Section 5.3.2).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-28

Category: Environmental Data – Pineapples and Soil

Date of Publication: 2005

Title: Determination of Arsenic (As), Cadmium (Cd), Chromium 

(Cr), Cobalt (Co) and Lead (Pb) in “Smooth Cayenne” 

Pineapple Fruit, Leaves Tissue and Soil Using Inductively 

Coupled Plasma Optical Emission Spectrometry (ICPOES)

Author(s): José L. López Morales

Affiliation: University of Puerto Rico, Mayagüez Campus

Publication Status: Masters in Chemistry Thesis

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

In 2004, researchers from the University of Puerto Rico’s Agricultural Extension Service in Vieques and 

the Land Authority of the Commonwealth of Puerto Rico collected study specimens. They collected a 

total of 72 samples of smooth cayenne pineapple fruit, leaf tissues, and soil from two pineapple 

plantations (one located in Barrio Luján in the civilian zone in Vieques and a control located in 

Barceloneta on the mainland of Puerto Rico). Inductively coupled plasma with optical emission 

spectrometry, together with U.S.EPA Method 200.7, were used to determine the total concentration of 

arsenic, cadmium, chromium, cobalt, and lead in the samples.

Table A-8. Heavy metals in pineapple and soil

Maximum Pineapple Fruit Concentration (mg/kg)

Arsenic Cadmium Chromium Cobalt Lead

Vieques below LOD or 

ND ND 2.3* ND ND

Barceloneta below LOD or 

ND ND 6.4 ND ND

Maximum Soil Concentration (mg/kg)

Vieques 169.7 3.9 6.7 9* 32.2

Barceloneta 268.4 or 

331.4† 6.3 64.2 or 77.4† 12.7 76.5

LOD = limit of detection

mg/kg = milligrams per kilogram

ND = not detected

*Exact number not reported—value estimated from a bar graph. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-29

†Both numbers are reported as the maximum detection.

The author concluded that samples from neither plantation showed contamination in the pineapple fruit 

or leaves. In all the fruit samples, arsenic, cadmium, cobalt, and lead were either below levels of 

detection or not detected. No contamination was observed in the pineapples from Vieques when 

compared with those from the Barceloneta plantation. Higher levels of metals were found in the soil at 

the Barceloneta plantation, which the author attributed to the soil’s natural composition. The author 

concluded that these results were in agreement with those of ATSDR and that all values were within 

accepted regulatory levels.

How ATSDR Addressed the Study Findings:

As part of its analysis of Vieques data, ATSDR evaluated the level of chromium—the only metal 

detected—in the pineapple fruit samples (see Chapter 5, Section 5.2.3). Using a standard intake rate for 

fruit consumption,35 the estimated exposure dose ATDSR calculated was below levels of health concern.

 

35 About 7 ounces of fruit a day (mean total fruit intake; USEPA 1997)
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-30

Category: Environmental Data – Livestock

Date of Publication: 2001

Title: Herbivorous: Additional Evidence of Heavy Metal 

Mobilization through the Food Web

Author(s): Arturo Massol-Deyá

Affiliation: Casa Pueblo de Adjuntas and University of Puerto 

Rico

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Soil Pathway 

Evaluation)

Study Findings

On August 18, 2001, researchers from Casa Pueblo de Adjuntas collected hair samples from goats 

grazing in Vieques’ Mount Santos and Santa María areas. As a reference, samples were also collected 

from goats that pasture in the main island of Puerto Rico. 

The publication reported that hair from goats grazing in Vieques contained higher levels of metals than 

did similar samples from goats on the main island. No mercury was detected in any goat hair (detection 

limit was 0.03 μg/g).

Table A-9. Metals detected in goat hair

Metals Detected in Goat Hair (μg/g)

Lead Cadmium Cobalt Nickel Aluminum

Main Island - Adjuntas, 

average

0.12 0.02 0.07 0.14 27.8

Vieques – Monte Santo, 

average

0.35 0.04 0.11 0.21 17.0

Vieques – Santa María, 

average

2.87 0.09 0.24 0.18 89.0

Monte Santo/Adjuntas 2.9 2.1 1.5 1.5 0.6

Santa María/Adjuntas 23.9 4.5 3.4 1.2 3.2

Maximum Ratio* 49.2 7.0 5.5 2.3 5.0

The authors concluded that their study confirmed the “spread of dangerous levels of contaminants 

through the Viequense’s food web.” Yet the study provided no comparison values.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-31

Additional information about this study is found in Science and Ecology: Vieques in Environmental Crisis, 

pages 52–53, by the same authors. They noted that goats and cattle that grazed on guinea grass and 

that other plants consumed by humans had higher concentrations of lead and cadmium.

How ATSDR and the Puerto Rico Department of Agriculture Addressed the Study Findings

The Soil Pathway Evaluation (see pages 57–58 in the PHA) addressed this issue as a community concern. 

Because this and other studies by the same researchers reported elevated levels of metals in plants and 

livestock, on August 7, 2001, the Puerto Rico Department of Agriculture placed an embargo on Vieques 

produce and livestock. The Puerto Rico Department of Agriculture, in cooperation with the Farmers 

Association of Puerto Rico, sampled grass, fruit-bearing trees, and bovine livestock from Monte 

Carmelo, Martineau, Monte Santo, Esperanza, Lujan, Gubeo, and western Vieques for cadmium, cobalt, 

copper, lead, manganese, and nickel. the Department of Agriculture and the Farmer’s Association 

concluded that the agricultural products from Vieques were suitable for consumption and did not 

contain toxic levels of these contaminants (Department of Agriculture 2001). Because the Department 

of Agriculture and the Farmer’s Association could not duplicate Massol’s results, the embargo was lifted. 

(El Nuevo Día 2001)

References

Department of Agriculture. 2001. Letter from Luis Colón to the Undersecretary of Agriculture concerning 

heavy metal tests on Vieques bovine livestock. 2001 October 17.

El Nuevo Día. 2001. They declare suitable the agricultural products in Vieques. 2001 December 13.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-32

Category: Environmental Data – Sea Life

Date of Publication: December 6, 1999

Title: Draft Findings in Vieques, Puerto Rico (AKA Heavy 

Metals in Reefs Where Bombs Are)

Author(s): James Porter

Affiliation: University of Georgia, Consultant to King and 

Spalding

Publication Status: Letter to law firm, King and Spalding

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Fish and 

Shellfish Evaluation)

Study Findings

On November 26–30, 1999, Dr. Porter conducted a field survey to examine the health of the coral reefs 

to the south of the Live Impact Area (LIA). 

The study reported on four objectives:

1. Collect samples of chemicals leaking from the bombs. The letter reported that analysis should 

have been available in late December, 1999. 

2. Determine the origin of craters in the area. Magnetometer readings suggested that metal 

objects (i.e., bombs) were imbedded in the crater walls. The study concluded that detonations 

caused the craters.

3. Determine whether bombing occurred after 1993. Dr. Porter used draft cards data and serial 

numbers to identify dates. But no data or conclusions regarding when bombing occurred were 

presented in the letter.

4. Determine the extent of chemical contamination. Analyses were not available at the time of the 

letter, but visual observations were reported:

a. Coral in contact with one of the leaking bombs was diseased and highly discolored.

b. 100–150 barrels and one compressed gas cylinder were located near a sunken barge.

c. 900–1000 barrels were located near a second barge that was broken in two. (The second 

barge was later identified as the former USS Killen, sunk during target practice.)

Dr. Porter’s letter recommended 

1. Identifying additional undersea areas with barrels—local fishers reported two additional areas.

2. Sampling barrels and gas cylinders to determine contents, management, and removal options.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-33

3. Sampling coral in the area to determine the coral’s age and hence the date when the barrels 

were sunk. [In a University of Georgia (UGA) press release dated December 13, 1999, Dr. Porter 

estimated the barges had sunk about 10 to 12 years previously.]

In a December 13, 1999, UGA press release, Dr. Porter reported seeing the sunken vessel and hundreds 

of 55-gallon drums. Available at: 

http://www.uga.edu/news/newsbureau/releases/1999releases/porter_rico.html.

Note: Dr. Porter published his results in 2004. Dr. Porter then concluded that “concentrations of 

explosive chemicals found in fish and lobster collected in the vicinity of the USS Killen are below the 

EPA’s Risk-Based Concentrations for commercially edible seafood.”

How ATSDR Addressed the Study Findings

Dr. Porter’s 1999 press release regarding leaking barrels prompted ATSDR’s exposure investigation team 

to sample fish in Vieques coastal waters. In 2001, ATSDR and U.S.EPA collected 104 fish and 42 shellfish 

from six locations in and around Vieques, including the area that Dr. Porter sampled near the former 

USS Killen. To determine other sampling locations and species of fish to collect, ATSDR relied on 

research by Universidad Metropolitana, discussions with the person who had petitioned ATSDR for an 

assessment of public health conditions on Vieques, residents of Vieques, and information provided in

the Vieques Special Commission Report. ATSDR collected grouper, snapper, parrotfish, grunt, goatfish, 

land crabs, queen conch, and spiny lobster. In addition, to address a specific community concern, ATSDR 

collected one honeycomb cowfish from a local fish market.

In 2003, ATSDR concluded the following in its Fish and Shellfish Evaluation:

 Explosive compounds were not detected in any of the edible fish and shellfish sampled from 

Vieques.

 Metals were detected in the fish and shellfish. 

 ATSDR evaluated several consumption scenarios, including eating fish every day. ATSDR found 

that it is safe to eat a variety of fish and shellfish from Vieques on a daily basis, including 

snapper (the most desirable and commonly consumed species). ATSDR concluded in 2003 that 

fish and shellfish caught at any of the locations are safe to eat, including fish and shellfish from 

areas in and around the former LIA and USS Killen. 

ATSDR is reevaluating mercury in fish and shellfish. The results from our evaluation of Vieques are in this 

report’s Chapter 2.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-34

Category: Environmental Data – Crabs

Date of Publication: January 12, 2000

Title: Biomagnification of Carcinogenic Metals in Crab Tissue, 

Vieques, Puerto Rico

Author(s): Arturo Massol-Deyá and Elba Diáz

Affiliation: Casa Pueblo de Adjuntas and University of Puerto 

Rico, Mayagüez

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Fish and 

Shellfish Evaluation)

Study Findings

In November 1999, researchers from Casa Pueblo de Adjuntas, in cooperation with the Biology 

Department of Recinto Mayagűez at the University of Puerto Rico, sampled male fiddler crabs from 

Icacos Lagoon in the Live Impact Area (LIA). As a control, the researchers took samples from Puerto 

Mosquito, just east of Esperanza. Icacos Lagoon is adjacent to Anones Lagoon; the researchers sampled 

soil in Anones Lagoon on February 12, 2000. The purpose of the research was to assess the potential 

transport of metals from soil in the LIA to other ecosystems.

At each location, researchers collected close to 35 fiddler crabs. They analyzed the extremities (i.e., 

levers and legs) separately from the body (i.e., shell and internal contents) for cadmium, chromium, 

cobalt, copper, lead, manganese, nickel, and zinc. 

The researchers then compared the levels of the heavy metals detected in fiddler crabs in Icacos Lagoon 

with the levels in the soils. They reported that with regard to cadmium, biomagnification was occurring; 

cadmium concentrations in the fiddler crabs were 10–20 times higher than in the soils. 

The researchers further reported that the average cadmium concentration (8.05 μg/g) of crab bodies 

(i.e., shell and internal contents) exceeded the World Health Organization’s (WHO) weekly maximum 

allowable concentration (0.007 μg/g) (approximately 60 μg/person/day for a 60 kg person) and the U.S. 

Food and Drug Administration’s (USFDA) daily critical concentration for persons older than 2 years (6 

μg/g).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-35

Table A-10. Metals detected in fiddler crabs

Metals detected in fiddler crabs (μg/g dry weight)

Location-Sample Copper Manganese Zinc Lead Chromium Cadmium Nickel Cobalt

Puerto Mosquito 

– extremities 49.94 86.56 62.99 n/d 25.48 1.74 17.15 12.17

Icacos Lagoon -

extremities 51.18 37.17 61.91 n/d 23.07 4.77 7.02 9.82

Puerto Mosquito 

- bodies 381.75 199.96 120.80 n/d 40.27 2.24 21.81 10.32

Icacos Lagoon -

bodies 499.91 97.75 75.59 n/d 40.70 8.05 18.95 35.69

nt detected/d = no

How ATSDR Addressed the Study Findings

Dr. Massol’s study established that fiddler crabs contained evidence of heavy metals. The study raised 

the question of what metal concentrations would be found in the crabs humans eat. 

But the study could not answer that question. It involved fiddler crabs, which humans do not eat. And 

the study did not separate the crab meat and shell—his analysis was of the shell and body contents 

combined. 

Dr. Massol’s report of high fiddler crab contamination did prompt ATSDR to sample land crabs, which 

humans do eat. In 2001, during the Fish and Shellfish Evaluation, ATSDR and U.S.EPA collected land 

crabs from three locations on Vieques, including the former LIA (see Sections IV and V and Appendix D 

of the PHA). No explosives compounds were detected in the edible portions of land crabs from any of 

the locations. Although metals were detected in land crabs, the levels were too low to be of health 

concern for people eating them.

ATSDR also reviewed the U.S. Fish and Wildlife Service’s (USFWS) 2001 ecological study in the Fish and 

Shellfish Evaluation of land crabs and fiddler crabs from west Vieques (see pages 12–13 of the 2003 

PHA). The USFWS research established that fiddler crabs and land crabs contained some heavy metals 

and pesticides. Because the USFWS samples were analyzed as whole body, the data from the report 

were useful to evaluate ecological contamination, but could not be easily converted to evaluate human 

health.

In 2006, an ATSDR health consultation assisted the USFWS to determine whether selected refuge areas 

could be opened to harvest land crab. In 2005, NOAA sampled 74 land crabs from 14 locations, analyzing 

them for explosive compounds, PCBs, organochlorine pesticides, and trace elements: 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-36

 The levels found in the land crabs were much lower than levels the scientific literature reported 

as causing harmful health effects. 

 Explosive compounds were not detected in any crab sample.

 No association was found between sampling location and land crab contaminant levels.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-37

Category: Environmental Data – Sea Grass

Date of Publication: June 2000

Title: Evaluación Preliminar de las Condiciones Químicas y 

Físicas de las Hierbas Marinas Thalassia testudium y 

Syringodium filiforme en Vieques. Research on the 

Physical and Chemical Conditions of Sea Grasses 

Thalassia testudium and Syringodium filiforme in Vieques 

[trans.]

Author(s): Fernando L. Herrera, Brenda Alicea Lopez, Blanca 

Diaz Perez, Siomara Cardona Vilella, Neritza Guerra 

Villanueva, and Maria C. Ortiz Rivera

Affiliation: Metropolitan University, School of Environmental 

Affairs; Universidad de Puerto Rico, Arecibo

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

The survey’s purpose was to perform a demographic and morphological assessment of Thalassia 

testudium and identify and determine the heavy metal content in Thalassia and Syringodium tissues. In 

sea grasses around Vieques, Dr. Herrera found “high concentrations” of aluminum, arsenic, iron, nickel, 

zinc, cadmium, cobalt, and lead. He also noted a close relation between past military activities and the 

pollution found in Vieques marine plants.

How ATSDR Addressed the Study Findings

Dr. Herrera’s report of heavy metals in sea grass—a substance humans do not eat—prompted ATSDR to 

sample conch, which humans do eat and which are sea-grass habitués. In 2001, ATSDR and U.S.EPA

collected 20 conchs from four sea grass beds around Vieques—north of the LIA, near the USS Killen, 

south of Esperanza, and west of the Monte Pirata Conservation Zone. These locations were chosen to 

represent productive fishing areas around the island. The conch meat was analyzed for explosive 

compounds and heavy metals:

 No explosive compounds were detected in conch from any of the locations.

 Metals were detected in conch, but those levels were too low to be of health concern for people 

who eat conch.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-38

Category: Environmental Data – Fish 

Date of Publication: June 2000

Title: Estudio Toxicológico de Metales Pesados en Poblaciones 

de Peces en la Isla de Vieques. Toxicological Study of 

Heavy Metals in Fish Populations at Vieques Island 

[trans.]

Author(s): Doris Caro PhD, Mei-Ling Nazario, and Noel Díaz

Affiliation: Metropolitan University

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Fish and 

Shellfish Evaluation)

Study Findings

Between December 1999 and April 2000, researchers from Metropolitan University collected fish from 

fish markets on the northern and southern coasts of Vieques and from the Parguera fish market in Lajas 

on the western side of the Puerto Rico mainland. 

To determine fish consumption rates and which species to sample, researchers used a questionnaire to 

ask Vieques residents about their dietary habits. Fifty-one residents responded.

The researchers concluded that “based on the data obtained . . . we were not able to verify our 

hypothesis of potential bioaccumulation in the fish . . . there is no clear relationship between fish weight 

and size and their metal content.” 

In the 78 fish samples analyzed, no cadmium was detected, and no lead was detected in the fish fillets. 

But the authors did report “high concentrations” of arsenic, mercury, selenium, and zinc.

Table A-11. Heavy metals in market fish

Heavy Metals in Market Fish—Fish Fillet Samples (ppm)

Lead Cadmium Arsenic Mercury Selenium Zinc

Vieques, north n/d n/d 0.325-1.676 0.019-0.048 0.123-1.290 1.2-9.1

Esperanza n/d n/d 0.290-0.658 0.022-0.048 0.168-0.713 3.3-8.2

Parguera, Main 

Island

n/d n/d 0.000-2.236 0.000-0.008 0.103-0.502 0.7-5.9

n/d, none detected

Cadmium detection limit, 0.005 ppm

Lead detection limit, 0.050 ppm
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-39

How ATSDR Addressed the Study Findings

In the 2003 Fish and Shellfish Evaluation (see pages 11–12 of the PHA), ATSDR evaluated whether the 

concentrations reported by the authors would result in harmful health effects for people consuming 

fish. ATSDR determined at the time that it was safe to eat fish from the sampled fish markets on a daily 

basis (i.e., all of the concentrations reported by Universidad Metropolitana were too low to be of health 

concern). The study did, however, provide valuable information on dietary habits: specifically, how often 

Vieques Islanders ate fish and what species they ate. ATSDR used that dietary information throughout 

the PHA.

In Chapter 2 of this report, ATSDR uses information from Dr. Caro’s survey and its own fish data to 

evaluate local fish consumption. The conclusions and recommendations from this evaluation are 

presented in Chapters 2 and 9. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-40

Category: Environmental Data – Sea Life

Date of Publication: March 8, 2004

Title: Radiological, Chemical, and Environmental Health 

Assessment of the Marine Resources of the Isla de 

Vieques Bombing Range, Bahia Salina del Sur, Puerto 

Rico

Author(s): James Barton and James Porter, PhD

Affiliation: Underwater Ordnance Recovery, Inc. and University 

of Georgia, respectively

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

This report describes research undertaken to determine the radiological, explosive, and chemical safety 

of the marine coastal waters in the vicinity of the USS Killen submerged wreck site. The report provided 

the following findings and conclusions:

Radiological

 Normal ambient radiological readings were found around the USS Killen and around the 55 

gallon drums.

 The readings indicate no health threat.

 The wreck of the USS Killen and 55 gallon drums should be left undisturbed to provide marine 

habitat.

Explosives

 Measurable readings of explosive residues were detected in some biota from the vicinity of the 

some bombs, with concentrations decreasing with increasing distance from the source.

 The readings from the decaying ordnance are localized, and pose a minimal toxicological threat 

to humans.

 The fish and lobster collected in the vicinity of the USS Killen are safe to eat. The concentrations 

of explosive chemicals are below the U.S.EPA’s risk-based concentrations for commercially 

edible seafood.

 As increased human access and environmental leaching patterns increase the risk of detonation, 

spread, and bioaccumulation in the immediate vicinity of UXO and related debris, all such items 

located from the high water mark on shore to the bottom of Bahia Salina del Sur should be 

removed.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-41

Metals

 Arsenic concentrations in fish (0.76 and 1.05 ppm) are above the U.S.EPA Risk-Based 

Concentration Guide (0.26 ppm).

 The authors noted that concentration of total arsenic in lobster collected from Site 1 (11.0 ppm) 

is within the normal range for Atlantic spiny lobster (10–20 ppm). The report text states that the 

arsenic levels are above the U.S.EPA Risk-Based Concentration Guideline (0.13 ppm) and may 

warrant a limited consumption advisory.

 Concentrations of barium, cadmium, chromium, and selenium in fish and lobster were below 

the U.S.EPA Risk Based Concentration Guidelines and within the ranges reported in the 2001 

ATSDR fish sampling event.

 Uranium and lead were not tested for fish collected from Sites 1 and 2.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-42

Table A-12. Sampling results of marine coastal waters

How ATSDR Addressed the Study Findings

Although the data were not published until 2004, in 1999 the University of Georgia issued a press 

release reporting that Dr. Porter discovered leaking barrels off the LIA coast. This report prompted 

ATSDR’s 2001 exposure investigation during which it sampled fish, crabs, lobster, and conch around 

Vieques. In 2001, ATSDR and U.S.EPA collected 104 fish and 42 shellfish from six locations on Vieques, 

including the area that Dr. Porter sampled near the former USS Killen. In 2003, ATSDR’s Fish and 

Shellfish Evaluation evaluated data from the agency’s 2001 sampling event and concluded the following:

 Explosive compounds were not detected in any of the edible fish and shellfish sampled from 

Vieques.

 Metals were detected in the fish and shellfish. 

 ATSDR evaluated several consumption scenarios, including eating fish every day. ATSDR found 

that it was safe to eat a variety of fish and shellfish from Vieques on a daily basis, including 

snapper (the most desirable and commonly consumed species). 

 Fish and shellfish caught at any of the locations were safe to eat, including from areas around 

the former LIA and the USS Killen. 

As part of its analysis of Vieques data, ATSDR evaluated the level of mercury in fish collected from the 

reefs surrounding Vieques and from a fish market on the island. The results from our evaluation of 

Vieques can be found in Chapter 2. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-43

Arsenic levels in fish and shellfish are often reported as total arsenic. It is important, though, to 

distinguish between inorganic arsenic, which is harmful to humans, and arsensobetaine, which is an 

arsenic-containing compound that is not harmful to humans. Arsenobetaine is not harmful because it is 

not metabolized by humans and is easily and quickly excreted within 2 to 3 days of ingestion. Most of 

the arsenic (usually less than 1%) in fish and shellfish, such as lobster, is the non-toxic arsensobetaine

(Sloth 2005, Fabris 2006, Green 2006). One particular study reported the percent inorganic levels in the 

spiny lobster (Panulirus species) was 0.01 to 0.2 percent (Peshut 2008). Panulirus is the genus of lobster 

found near Vieques and other parts of the Caribbean.

References

Sloth JJ, Larsen EH, Julshamn K. 2005. Survey of inorganic arsenic in marine animals and marine certified 

reference materials by anion exchange high-performance liquid chromatography-inductively coupled 

plasma mass spectrometry. J. Agric Food Chem 53;6011-6018.

Fabris G, Turoczy NJ, Stagnitti F. 2006. Trace metal concentrations in edible tissue of snapper, flathead, 

lobster, and abalone from coastal waters of Victoria, Australia. Ecotoxicology and Environmental Safety 

63;286-292.

Peshut PJ, Morrison RJ, Brooks BA. 2008; Arsenic speciation in marine fish and shellfish from American 

Samoa. 71(3);484-492.

Greene R, and Crecelius E. 2006. Total and inorganic arsenic in mid-Atlantic marine fish and shellfish and 

implications for fish advisories. Integrated Environmental Assessment and Management 2(4);344-354.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-44

Category: Environmental Data – Sea Life 

Date of Publication: February 21, 2009

Title: Carcinogens Found in Marine Life in Island of Vieques in 

Puerto Rico

Author(s): James Porter, PhD

Affiliation: University of Georgia

Publication Status: Press Release

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

This press release announced that Dr. Porter would present the findings of his 1999 sampling event at 

the Second International Dialogue on Underwater Munitions on February 25–27, 2009 in Honolulu, 

Hawaii. 

Dr. Porter’s 2004 report recommended leaving the unexploded bombs in place. According to the new 

press release, he now recommended ordnance removal using an ordnance recovery system designed by 

Underwater Ordnance Recovery, Inc., and using the technical expertise of machinists at the University of 

Georgia instrument shop.

The press release noted that carcinogenic material was detected up to 2 meters from the bombs and 

quoted Dr. Porter as saying a future step will be “to determine the link from unexploded munitions to 

marine life to the dinner plate.”

How ATSDR Addressed the Study Findings

The Centers for Disease Control and Prevention (CDC) participated in the panel presentation at the 

Second International Dialogue on Underwater Munitions. ATSDR considered Dr. Porter’s new 

information as part the agency’s analysis of Vieques data.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-45

Category: Environmental Data - Air

Date of Publication: May 1999 

Title: Contaminación Producida por Explosivos y Residuos de 

Explosivos en Vieques, Puerto Rico. Contamination 

Produced by Explosives and Explosive Residues in 

Vieques [trans.]

Author(s): Rafael Cruz Pérez, PE

Affiliation: College of Engineers

Publication Status: Dimension magazine

Peer Review Status: None

Cited Previously by ATSDR: Yes (2003 Public Health Assessment: Air Pathway 

Evaluation)

Study Findings

Dr. Cruz-Pérez modeled air quality effects resulting high explosives used at Vieques.

Dr. Cruz-Pérez concluded that 

 Detonation of a single artillery shell (i.e., a 105 mm mortar projectile) could emit 400 kilograms 

of soil and explosive residue into the air.

 Ambient air concentrations of pollutants from military training exercises are inversely 

proportional to the downwind distance raised to the 1.5 power.

 A single explosion of an artillery shell would cause ambient air concentrations of particulate 

matter in the residential areas of Vieques to increase by 33 μg/m3over the course of 15.9 

minutes. 

 Including contributions from background, an unspecified level of military training exercises 

would lead to particulate matter concentrations of 197 μg/m3in the residential areas of 

Vieques.

How ATSDR Addressed the Study Findings

When ATSDR first began its evaluation of the air pathway, two dispersion modeling studies were 

available—one prepared by Navy contractors and the other by Dr. Cruz-Pérez, whose air modeling of 

particulate matter disagreed with the Navy’s modeling. This prompted ATSDR to hire three modeling 

experts to review both studies critically. After examining the reviewers’ findings, ATSDR decided to 

conduct an independent modeling study that did not suffer from some of the previous studies’ 

shortcomings. Note that given the limited air sampling that occurred at Vieques during the time when 

the Navy used live bombs, modeling was necessary. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-46

The Air Pathway Evaluation conclusions were based largely on ATSDR’s modeling effort. The Air Pathway 

Evaluation also included ATSDR’s evaluation of Dr. Cruz-Pérez’s air modeling analysis (see pages D-11 

through D-15 of the PHA).

Dr. Cruz-Pérez’s article provided no hard evidence (e.g., references, equations, input parameters) to 

defend the estimated air emission rate of 400 kilograms of soil per single artillery shell. In Appendix D of 

the PHA, to estimate emissions, ATSDR used a published model and documented all input parameters 

and assumptions. 

Dr. Cruz- Pérez based the estimated ambient air concentrations on an assumed decay rate with 

downwind distance. All three expert reviewers questioned Dr. Cruz-Pérez’s estimated decay rate, with 

one expert reviewer citing peer-reviewed publications suggesting that pollutants from instantaneous 

plumes—like those associated with bombing activity—would decay much more quickly than Dr. CruzPérez’s calculations suggested. Expert reviewers identified at least one error in Dr. Cruz-Pérez’s 

calculations, and ATSDR noted that the approach did not take into account parameters known to affect 

atmospheric dispersion (e.g., initial cloud height, atmospheric stability, wind speed, wind direction, 

mixing height). To estimate ambient air concentrations at Vieques, ATSDR used a U.S.EPA-recommended 

model (CALPUFF) with options for modeling “puff” (i.e., instantaneous) sources, such as the bombing 

events at Vieques. ATSDR’s modeling predicted the air quality effects of more than 75 pollutants—not 

just a single pollutant. And in its PHA, ATSDR fully documented all model assumptions, input 

parameters, and run-time options.

By contrast, Dr. Cruz-Pérez estimated particulate matter ambient air concentrations on days when 

military training exercises occurred. Expert reviewers noted, however, that these estimates do not 

document the averaging time for the concentrations (e.g., 24-hour, annual average) nor do they specify 

the particle size (e.g., PM10, PM2.5, TSP), both of which are important health evaluation considerations. 

ATSDR’s modeling analysis accounted for these shortcomings by specifying the particle sizes considered 

and by evaluating both acute and chronic exposure durations. The PHA documents all ambient air 

concentrations ATSDR estimated during the modeling effort.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-47

Category: Environmental Data - Water and Soil

Date of Publication: May 11–16, 1978

Title: Vieques Litigation Support: Explosives Analyses of Water 

and Soil Samples Taken on Vieques Island, Puerto Rico

Author(s): JC Hoffsommer and DJ Glover 

Affiliation: Navy, Naval Surface Weapons Center, Explosives 

Chemistry Branch, MD

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: Yes (2001 Public Health Assessment: Drinking Water 

Supplies and Groundwater Pathway Evaluation and 

2003 Public Health Assessment: Soil Pathway 

Evaluation)

Study Findings

From May 11 to May 16, 1978, the Naval Surface Weapons Center (NSWC) obtained and analyzed water 

and soil samples from inside and outside the Vieques Island live impact area (LIA). The samples were 

collected 1 week after a military exercise in which live ordnance was used at the LIA. Samples were 

analyzed for TNT, RDX, and Tetryl. The study also analyzed for the biotransformation products of TNT: 4-

amino-2, 6-dinitrotoluene, and 2-amino-4, 6-dinitrotoluene. NSWC detected no biotransformation 

products.

NSWC did find that concentrations of TNT and RDX were below the toxicological hazard levels suggested 

by the U.S. Army Medical Bioengineering Research and Development Laboratory in 1977. No guideline 

was given for Tetryl.

NSWC took 26 water samples: 15 within the LIA (one drinking water) and 9 in Navy-controlled areas 

west of LIA (one drinking water) including the Naval Ammunition Facility (NAF) and Camp Garcia, 

drinking water in Isabel Segunda, and drinking water in Esperanza. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-48

Table A-13. NSWC water sample results

Station Station Description TNT, ppm* RDX, ppm Tetryl, ppm

Health Guideline cited in study <0.01 <0.03 NA

Drinking Water Samples

5 Pump house water, NAF magazine Area Absent 0.00006 Absent

6 Drinking Water, Esperanza Absent 0.00004 Absent

7 Drinking Water, Isabel Segunda Absent 0.00004 0.0005

OP-1 Drinking water Cerro Matias (within LIA)

Surface Water Samples

1 Magazine water run-off NAF Area

(maximum detected off LIA)

<0.00004 0.001 <0.0009

19 Crater A run-off water

(maximum TNT detected within LIA)

0.00003 0.00045 Absent

20 Lagoon water

(maximum RDX detected within LIA)

Absent 0.0059 Absent

*ppm = parts per million

NSWC collected six soil samples on land under Navy control; no samples were taken in residential areas. 

Like the water samples, these samples were analyzed for TNT, RDX, Tetryl, and biotransformation 

products of TNT. In addition, the soil samples were analyzed for acetone extractables. No Tetryl or 

biotransformation products were detected.

Table A-14. NSWC soil sample results

Station Station Description TNT, ppm* RDX, ppm % Acetone

Extractables

Health Guideline cited in study <0.01 <0.03 NA

8 Soil near Bahia de la Chiva, Maneuver Area, 

Camp Garcia (maximum detected TNT)

0.0060 0.0030 0.04

24 Soil from Crater b, Demolition Range #6 0.0071 0.0054 0.14

20 Lagoon soil

(maximum % acetone extractables detected)

Absent 0.024 0.31

*ppm = parts per million
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-49

How ATSDR Addressed the Study Findings

ATSDR evaluated the data from this report as part of the Drinking Water Supplies and Groundwater 

Pathway Evaluation (see page 32 and Appendix E of the drinking water PHA) and the Soil Pathway 

Evaluation (see Section IV of the PHA).

The concentrations of explosive compounds reported in both drinking water and lagoon water were well 

below levels considered harmful to human health. Past exposure to these compounds did not pose a 

public health hazard.

The drinking water samples (4) and the chemicals analyzed in this study were both limited. To arrive at 

its drinking water health call, ATSDR used additional data. In the drinking water PHA, Appendix B lists 

sampling events and Appendix C lists chemicals for which analyses were performed. 

Other sampling events detected no RDX or tetryl in the drinking water supplies. The study noted, “a 

completely positive identification was not possible due to the extremely low concentrations found.” It 

further noted, “if these explosives are present, the concentrations do not exceed the values reported 

here.” The Navy laboratory that analyzed the samples had developed sensitive techniques to test for 

explosives in seawater and particularly to detect explosive compounds. These methods were more 

sensitive than the current U.S.EPA laboratory methods now considered the standard for environmental 

work. The reported soil levels were below comparison values and did not indicate a health hazard. 

The number of soil samples (6) was limited. Thus for its soil health call, ATSDR used additional data. For 

example, in 1999 and 2000, the Navy (at ATSDR’s request) and Servicios Científicos y Técnicos collected 

soil samples from areas where the protestors lived. Protestors who lived on the LIA for a year (1999–

2000) endured the longest exposure to contaminants in the LIA soil. ATSDR reviewed the data and 

determined that the protestors were not exposed to harmful levels of soil-embedded chemicals.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-50

Category: Health Outcome Data – Heart Disease

Date of Publication: January 2001

Title: Vibroacoustic Disease Induced by Long-Term Exposure 

to Sonic Booms

Author(s): R Torres, G Tirado, A Roman, R Ramirez, H Colon, A 

Araujo, F Pais, W Maciniak, J Nobrega, A Bordalo e Sa, 

JMC Lopo Tuna, M Alves-Pereira, NAA Castelo Branco 

Affiliation: Virtual Research Group and Center for Human 

Performances

Publication Status: Draft manuscript

Peer Review Status: None

Cited Previously by ATSDR: Yes (2001 Vieques Heart Study Expert Panel Review)

Study Findings

In January 2001, a pilot study comparing the echocardiograms of commercial fishers in Vieques and in 

Ponce Playa, Puerto Rico reported large proportion of Vieques fishers with substantial valvular 

abnormalities and pericardial thickening—conditions not seen in Ponce Playa. The possible 

abnormalities noted in the Vieques fishers were attributed to "vibro-acoustic disease" (VAD), which 

Portuguese investigators had described in the medical literature. VAD was said to occur as the result of 

noise and vibrations caused by naval exercises on Vieques Island. By Presidential directive, the 

Department of Health and Human Services undertook an investigation of the issues raised by the study. 

The Department, in turn, referred this request to ATSDR, then currently investigating environmental 

public health issues in Vieques. The Cardiovascular Diseases Branch of Centers for Disease Control (CDC) 

provided considerable assistance in this investigation.

Concurrent with this request, the Ponce School of Medicine (PSM), led by President and Dean Dr. 

Manuel Martínez Maldonado, began a more definitive study of possible cardiac abnormalities among 

Vieques residents. This study sought to overcome methodological problems in the earlier pilot study. On 

March 29–30, 2001, scientists from ATSDR and CDC met with the PSM investigators and agreed that 

their review and interpretation of the findings should include an independent opinion of recognized 

practitioners and scientists. 

How ATSDR Addressed the Study Findings

In July 2001, ATSDR, PSM, and CDC co-sponsored an expert panel to review PSM's follow-up study. The 

panel’s principal conclusion was that neither the PSM nor the Mayo Clinic readings contained 

information indicating a cardiac health problem in the commercial fishers from either location. The 

initial report of gross valvular pathology from the pilot study was not replicated. All reviewers agreed 

that contrary to pilot study reports, no clinically relevant difference in pericardial thickness surfaced 

between Vieques and Ponce Playa subjects. Moreover, neither the PSM nor the Mayo Clinic 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-51

measurements showed any subject's pericardial thickness to be larger than 2 mm—a metric the 

published literature considered the upper limit of normal.

The PSM study does not support findings of cardiac pathology among Vieques fishers. Because of the 

inability of trans-thoracic echocardiography to measure reliably the small differences found, those 

reported are likely due to measurement error—intrinsic to the technique, not to scientists who use it. 

This in all likelihood accounts for the different results obtained when Mayo Clinic readings of pericardial 

thickness were used in place of PSM readings. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-52

Category: Human Biomonitoring – Hair and Stool 

Date of Publication: circa 2000

Title: Investigación Científica de los Metales Tóxicos habidos 

en el Terreno Biológico de niños y adultos viequenses y 

sus efectos sobre los Minerales Nutrientes. Scientific 

Investigation of Toxic Metals Present in the Biological 

Terrain of Vieques Children and Adults and Their Effects 

on Nutrient Minerals [trans.]

Author(s): Carmen Colón de Jorge, Edgardo Santiago, John 

Brooks, Francisco Lopez Perez, Jaime Rivera, Rafael 

Valle 

Affiliation: College of Physicians and University of Puerto

Publication Status: draft manuscript (unpublished)

Peer Review Status: None

Cited Previously by ATSDR: Not cited, but basis for the 2001 Hair Analysis Panel 

Discussion

Study Findings

In 1999 and 2000, Dr. Colón de Jorge collected hair and stool samples from Vieques residents. The 

doctor stated that 45–50% of these nonrandomly selected people were poisoned with mercury. Using 

results from stool samples, the doctor found that 3 out of the 6 children tested in Vieques had metal 

concentrations in stools above the reference range provided by the clinical laboratory (i.e., Doctor’s 

Data). The doctor also reported that 5 out of 6 children tested had antimony and arsenic in stool 

samples that exceeded the lab’s reference range. And these were children who, unlike adults, might not 

be exposed to metals in paint, cigarette paper, tobacco, old pots, makeup, and hair dye. 

Dr. Colón de Jorge reported that 30 hair samples were collected from Vieques residents with selfreported health conditions. The doctor also concluded that 1) 50% of the people tested were 

contaminated with antimony compared with 29% from a control population, 2) 50% of the people 

tested were contaminated with arsenic compared with 29% from a control population, and 3) 50% of 

the people tested had a selenium imbalance. Dr. Colón de Jorge pointed out that antimony levels were 

high because it was used in ballistics on the island, thus making the case that naval bombardment 

activity was the reason antimony levels were high in children.

Dr. Colón de Jorge also used the following statements to summarize the results of seven control 

patients:

 None of the seven patients showed total toxic levels of metals. Two cases had antimony above 

the reference range established by the laboratory compared with 29% of those investigated 

outside Vieques. Selenium was normal for exogenous contamination. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-53

 Two cases had arsenic above the reference range compared with 29% of the cases outside 

Vieques. Selenium was normal for exogenous contamination.

 Because their selenium levels were normal and within the reference range, the seven control 

patients did not have endogenous heavy metals contamination.

 Dr. Colón de Jorge collected hair samples at random from seven persons in Rio Piedras, on the 

main island of Puerto Rico. None of the results showed toxic levels of heavy metals. By contrast, 

tests of 21 of 30 persons (i.e., 63%) from Vieques with known health conditions (and thus not 

randomly selected) detected various metals at toxic levels. 

 Dr. Colón de Jorge’s report contains several appendices with additional information, mostly 

focused on how to evaluate and interpret elemental results in hair. One of the appendices 

contained a Doctor’s Data report entitled Comprehensive Interpretations for Hair Elements from 

Al to Zn (Quiq 1998).

How ATSDR Addressed the Study Findings

To determine the relationship between hair data and the potential for adverse health effects, ATSDR 

sought the assistance of external experts. In June 2001, ATSDR convened an expert panel to discuss the 

state of the science relating to analyzing hair for environmental exposure (ATSDR 2001). The panel 

comprised persons from state and federal government agencies, academia, and private practice whose 

expertise, interests, and experience covered a wide range of relevant technical disciplines. 

The panelists agreed that 

. . . for most substances, insufficient data currently exist that would allow the 

prediction of a health effect from the concentration of the substance in hair. 

The presence of a substance in hair may indicate exposure (both internal and 

external), but does not necessarily indicate the source of exposure. 

The panel noted that—provided external contamination can be ruled out—a relationship between 

contaminant concentrations in hair and any kind of measurable outcome have only been established for 

methylmercury and, to a limited extent, for arsenic.

The panel recognized that laboratory methods are available to measure the levels of some 

environmental contaminants in hair, but commented that procedures needed to be standardized to help 

ensure more accurate and reliable results. They also identified several factors that limited the 

interpretation of even the most accurate, reliable, and reproducible laboratory results.

The community concern about hair analysis was briefly addressed in the 2001 Soil PHA (see page 58).

References

Agency for Toxic Substances and Disease Registry. 2001. Summary Report, Hair Analysis Panel 

Discussion: Exploring the State of the Science. June 12–13, 2001. Atlanta: Division of Health Assessment 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-54

and Consultation and Division of Health Education and Promotion; 2001 December. Available from:

http://www.atsdr.cdc.gov/hac/hair_analysis/ [accessed 2010 Jan 13]. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-55

Category: Human Biomonitoring – Hair

Date of Publication: January 29, 2002 

Title: Heavy Metal Exposure and Disease in the Proximity of a 

Military Base

Author(s): Carmen Ortiz Roque 

Affiliation: Private practice, GINECO, San Juan, PR

Publication Status: draft manuscript (unpublished)

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

From January 2000 to July 2001, Dr. Carmen Ortiz Roque collected hair samples from 203 Viequenses. 

Table A-15 shows hair data for various metals. 

Table A-15. Results of metal analysis of hair samples collected from Viequenses from January 2000 to 

July 2001.

Metal in ppm % Elevated Average (95% CI) Females Males Children <10 

years old

Mercury, N= 205 33% > 1 ppm 2.07 (0 – 8.9) 2.87 1.08 1.89

Aluminum, N=145 56% > 17 ppm 25.74 (10.52-25.75) 26.45 24.18 34.94

Cadmium, N=205 26% > 0.47 ppm 0.65 (0-5.0) 0.75 0.55 Not available

Lead, N=205 2.9% > 25 ppm 8.07 (0-19.0) 4.28 12.47 Not available

Arsenic, N=205 0 > 1 ppm 0.18 (0 – 3.0) 0.141 0.233 Not available

Dr. Ortiz Roque stated that elevated levels of mercury (33%), aluminum (56%), cadmium (26%), and lead 

(6%) were found in the participants. Hair arsenic levels were not elevated. 

Dr. Ortiz Roque further stated that 22% of women and 60% of children sampled in Vieques had mercury 

levels above what the United States considers the 90th percentile. 

A subset of 22 Vieques matched pairs of mothers and their children 5 years or younger was analyzed 

further. Dr. Ortiz Roque reported a significant correlation between mercury hair levels in mothers and 

their children (Pearson’s correlation 0.93, p = 0.0001). Average aluminum hair concentration for 

Viequenses was 25.74 ppm, and this concentration exceeded the upper limit of a standard human 

population. Dr. Ortiz Roque pointed out that aluminum levels in children’s hair are normally higher than 

in adults.

The doctor concluded that the data showed Viequenses had internal exposure to heavy metal, and that 

the data were supported by the high percentage of women and children with hair mercury levels above 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-56

the 90th percentile compared with the continental United States. While none of the women in the 

NHANES 1999 survey had mercury hair levels above 12 ppm, 3 of 45 Viequenses women had hair levels 

above 12 ppm (i.e., 15.41, 25.26, and 101.3 ppm).

Dr. Ortiz Roque concluded that the correlation between mother and offspring hair showed that mercury 

exposure occurred in utero, that Viequenses exposure to mercury was too high to be considered safe, 

and that mercury was used in the detonators.

How ATSDR Addressed the Study Findings

As mentioned previously, ATSDR convened a panel of experts who agreed that 

. . . for most substances, insufficient data currently exist that would allow the 

prediction of a health effect from the concentration of the substance in hair. 

The presence of a substance in hair may indicate exposure (both internal and 

external), but does not necessarily indicate the source of exposure. 

Nevertheless, Dr. Ortiz Roque documented several mothers with elevated mercury levels in hair and her 

findings are described in Chapter 3. Viequenses who remain concerned about exposure to mercury, 

cadmium other metals, or metalloids should consult their healthcare provider to discuss the need for 

and cost of testing.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-57

Category: Human Biomonitoring – Hair

Date of Publication: 2004

Title: Mercury Contamination in Reproductive Age Women in a 

Caribbean island: Vieques

Author(s): Carmen Ortiz Roque, Yadiris López-Rivera 

Affiliation: Private Practice, GINECO, San Juan, Puerto Rico

Publication Status: J Epidemiol Community Health 2004;58:756–57

Peer Review Status: Yes

Cited Previously by ATSDR: No

Study Findings

Dr. Ortiz Roque published the mercury data from the 2001 hair study of Vieques residents. That study 

investigated hair mercury levels in women 16 to 49 years old who lived on the island of Vieques. The 

doctor compared those levels with women from San Juan and Ceiba, Puerto Rico. Women were 

excluded whose hair had been chemically treated within 3 months of the test. A 1.5-cm proximal hair 

sample was collected and analyzed by one of two licensed laboratories. 

Dr. Ortiz Roque reported statistics on 41 Viequenses women together with information about seafood 

consumption, and compared these data with mainland Puerto Rico and the United States. Table A-15 

summarizes the data. Dr. Ortiz Roque used margin of exposure (MOE) to define unsafe exposure levels. 

Table A-16. Mercury hair results in women published by Dr. Ortiz Roque in 2004

# Age

Mercury in ppm

Margin of 

Exposure

Seafood Consumption % 

Women> 

Median Mean RfD

90th

Percentile Total Local Local fish

Vieques 41 31.8 0.66 4.4 8.96 1.3 4.9 2.9 1.9 26.8

PR 45 29.9 0.38 0.4 1 12 2.8 1.1 0.7 6.6

US 702 NA 0.2 1.4 8.6 NA NA NA 7

Dr. Ortiz Roque’s MOE approach originated in a 2001 MMWR article and with the National Research 

Council. The NRC recommended a 5% effect level derived from the 95% lower confidence limit of a 

benchmark dose (BMDL). The basis for the 5% effect level is abnormal scores on cognitive function tests 

in children exposed in utero to methylmercury. The NRC recommended that the U.S.EPA derive their 

Reference Dose using a BMDL of 58 ppb methylmercury in cord blood, which was identified as the 5% 

effect level from a Faroe Islands study using statistical models. The 58-ppb cord blood translates to 12 

ppm in hair (Ortiz Roque 2004; NRC 2000).

Results showed that the 90th percentile mercury hair concentration in Vieques women was 8.96 ppm 

compared with 1 ppm in women from Puerto Rico and 1.4 ppm in women from the United States. Dr. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-58

Ortiz Roque concluded that Viequenses women of reproductive age were exposed to mercury 

concentrations unsafe to their developing fetuses.

How ATSDR Addressed the Study Findings

Dr. Ortiz Roque documented several mothers with elevated mercury levels in hair. Her findings are 

described in Chapter 3.

Viequenses who remain concerned about exposure to mercury, cadmium, other metals, or metalloids

should consult their healthcare provider to discuss the need for and cost of testing.

References

[NRC] National Research Council. 2000. Toxicological Effects of Methymercury. Washington (DC): 

National Academy of Sciences, National Research Council. Pubs: National Academy Press. 

Ortiz Roque C, López-Rivera Y. 2004. Mercury contamination in reproductive age women in a Caribbean 

island: Vieques. J. Epidemiol Comm Health 58:756–57.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-59

Category: Human Biomonitoring – Hair, Nails and Urine

Date of Publication: 2004 and 2006-2008

Title: Arsenic Detected in Urine, Nails, and Hair Study (Exact 

title not available)

Author(s): Carlos Rodríguez Sierra 

Affiliation: University of Puerto Rico, Department of 

Environmental Health

Publication Status: El Vocero (newspaper article)

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

Dr. Carlos Rodríguez Sierra apparently conducted two urine arsenic studies in Vieques. The first was 

before 2004 and the results were presented at several public health conferences, including the 2004 8th 

International Symposium on Metal Ions in Biology and Medicine. The second arsenic study was from 

2006 to 2008 and was reported in El Vocero in March 2009. Neither study has been published in a peerreviewed journal. ATSDR has requested that Dr. Rodríguez Sierra share a manuscript or summary 

statistics but have not received a response. Dr. Rodriquez Sierra is with the Department of 

Environmental Health, Site Medical Sciences, University of Puerto Rico.

The following information comes from a March 2009 newspaper article in El Vocero describing arsenic 

exposure in Vieques residents from eating fish. The article stated that inorganic arsenic was found in a 

representative sample of Viequenses with high fish consumption.

Dr. Rodríguez Sierra identified two groups in Vieques: one consisted of 30 persons who consumed 

substantial quantities of fish. Another consisted of 22 persons who consumed very little fish. As a 

biomarker of short-term exposure, the researchers measured the levels of inorganic arsenic in urine. As 

a biomarker of long-term exposure, they measured arsenic in nails and in hair.

The article stated that the researchers measured arsenic in urine and found that, on average, levels in 

urine, hair and nails were generally low. Nevertheless, some people, and particularly some men, who 

ate fish frequently had higher concentrations of inorganic arsenic in their nails—an indicator of longterm exposure.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-60

How ATSDR Addressed the Study Findings

Because the data were not available, ATSDR considered the results qualitatively in Chapter 3. 

Viequenses who remain concerned about exposure to mercury, cadmium, other metals, or metalloids

should consult their healthcare provider to discuss the need for and cost of testing.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-61

Category: Human Biomonitoring – Blood

Date of Publication: November 2006

Title: Executive Summary of the Prevalence of Heavy Metals in 

Vieques

Author(s): Juan Alsono Echanove and Luis Manuel Santiago

Affiliation: Commonwealth of Puerto Rico, Department of Health

Publication Status: draft manuscript

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

Beginning in 2004, the Puerto Rico Department of Health (PRDOH) conducted a two-phase, 5-year, 500 

person, epidemiological study of heavy metals in residents’ blood, urine, and hair. The results were 

presented in a draft manuscript in 2006. In the first phase, the PRDOH study conducted interviews and 

laboratory analysis on 1) arsenic in hair and urine, 2) nickel in hair and urine, 3) cadmium in hair and 

urine, 4) mercury in blood, 5) lead in blood, 6) aluminum in blood, and 7) uranium in urine. The second 

phase of the investigation involved collecting and analyzing blood samples from Phase I participants 

whose tests showed metals at toxic levels. Phase II was carried out from December 2005 to March 2006. 

The PRDOH manuscript reported the main findings of this study as

 Detectable levels of at least one heavy metal were found in over 90% of the population.

 The levels of aluminum in blood, arsenic in urine, and nickel in hair were over the laboratory 

threshold in more than 20% of the study participants. Arsenic results in urine were for total 

arsenic, not inorganic arsenic.

 Geometric means for uranium in urine, mercury in blood, lead in blood, aluminum in blood, 

nickel in hair, and cadmium in urine were significantly higher than geometric means from the 

1999 NHANES survey.

 None of the geometric means identified by the laboratory was over the laboratory’s toxicity 

threshold.

 For arsenic, cadmium, and nickel, the use of cigarettes, consumption of seafood, and use of hair 

dye were identified as risk factors for levels above the laboratory threshold.

 Fifteen persons (3%) were identified with levels above the toxicity threshold for aluminum in 

blood (10), lead in blood (2), mercury in blood (1), and cadmium in urine (2).

 In the follow-up study on 10 of the 15 persons, only one person with levels above the toxicity 

threshold was identified.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-62

The PRDOH manuscript suggested establishment of a voluntary health registry of Vieques residents. A 

health registry would 1) allow for systematic documentation of factors related to potential risks, 2) 

identify people with early signs and symptoms that may be associated with illness, and 3) facilitate early 

care and health service access needs. 

The PRDOH manuscript pointed out that blood lead levels were unknown for the 1,000 Vieques children 

6 years of age and younger. This high-risk group is more vulnerable to lead exposure than are adults. 

The PRDOH manuscript stated that an epidemiologist would be appointed to work towards establishing 

this program, which will follow CDC guidelines for case management. Whether at this time this program 

has been implemented is unknown. 

How ATSDR Addressed the Study Findings

The PRDOH biomonitoring study provided much insight into metal exposure for Vieques residents. Some 

results from the PRDOH study suggested elevated levels of various metals, thus raising concerns about 

excessive exposure on the island. The PRDOH study is described in detail in Chapter 3. Viequenses who 

remain concerned about exposure to mercury, cadmium, other metals, or metalloids should consult 

their healthcare provider to discuss the need for and cost of testing.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-63

Category: Human Biomonitoring – Hair 

Date of Publication: None

Title: Title not determined

Author(s): Dr. John Wargo

Affiliation: Yale University, Connecticut

Publication Status: draft manuscript (not available)

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

Yale University’s Dr. John Wargo considered analyzing data and preparing a paper about heavy metals in 

Viequenses hair. However, he has informed ATSDR that he no longer plans to do this analysis because 

of quality assurance/quality control issues with the hair data and because of problems with using hair to 

measure most metals.

How ATSDR Addressed the Study Findings

No study findings will be available.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-64

Category: Health Outcome Data

Date of Publication: November 7, 2006

Title: Cancer Incidence and Mortality in Vieques 1990–2001

Author(s): Nayda R. Figueroa, MD, MPH, Erick Suárez, PhD, 

Taina De La Torre, MS, and Mariela Torres, MS

Affiliation: Commonwealth of Puerto Rico, Department of Health 

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

From 1973 to 1989, the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) 

Program in part funded the Puerto Rico cancer registry (PRCR). After 1989, the contract between the 

PRCR and SEER was not renewed, and until 1997, PRCR operated on local funding. In 1997, the PRCR 

applied for and received funding from the Centers for Disease Control and Prevention (CDC) through a 

cooperative agreement via the National Program of Cancer Registries. In calendar year 1998, beginning 

with cancer cases diagnoses, the PRCR provided data to the CDC .

In this report, cancer incidence and mortality in Vieques during 1990–2001 for the most common 

anatomical sites (i.e., breast, colorectal, cervical, oral cavity and pharynx, lung and bronchus, and 

prostate) and a few other cancers potentially associated with environmental exposures (i.e., liver and 

intrahepatic bile duct, kidney and renal pelvis, bladder, lymphoma and leukemia) were assessed for two 

periods (1990–1995 and 1996–2001). Cancers were also assessed by sex where applicable. To present 5-

year cancer incidence and mortality rates is standard practice, as noted in publications such as SEER’s 

Cancer Statistics Review, the North American Association for Central Cancer Registries' Cancer in North 

America, and joint publications such as the United States Cancer Statistics. 

After age adjustments, the analysis identified increased cancer incidence in Vieques for some specific 

anatomical sites as well as in all cancers combined. Significant increases were only identified in the 

1990–1995 time period. Statistically significant, age adjusted standardized incidence ratios (SIRs) with 

corresponding 95% confidence intervals (95% CIs) were 

 All cancers for both sexes combined (SIR=1.19; 95%CI 1.02, 1.39); 

 Lung and bronchus for both sexes combined (SIR=2.25; 95%CI 1.35, 3.52); 

 Lung and bronchus for men (SIR=2.24; 95%CI 1.19, 3.83); and 

 Prostate (SIR=1.47; 95%CI 1.03, 2.03).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-65

After age adjustments, the analysis identified an increased cancer mortality in Vieques for some specific 

anatomical sites as well as for all cancers combined. Statistically significant, age adjusted standardized 

mortality ratios (SMRs) with corresponding 95% confidence intervals (95% CIs) were 

 All cancers for both sexes combined, 1990–1995 (SMR=1.26; 95%CI 1.01, 1.57); 

 All cancers for women, 1990–1995 (SMR=1.43; 95%CI 1.01, 1.96); 

 All cancers for both sexes combined, 1996–2001 (SMR=1.25; 95%CI 1.01, 1.52); 

 Breast cancer, 1990–1995 (SMR=0.26; 95%CI 0.03, 0.92); and 

 Oral cavity and pharynx for men, 1990–1995 (SMR=3.96; 95%CI 1.08, 10.00).

As mentioned briefly in the document and as confirmed by Dr. Figueroa (personal communication, July, 

2009), some follow up was necessary to identify cases in Vieques that were not processed uniformly 

with the rest of PR. One example relates to documentation of age for cases in the registry. For this 

assessment, on the island of Vieques all cases indicating residence had their ages confirmed. But this 

practice was not followed on the PR main island. If a case did not have a known age, it was omitted from 

any rate calculations. Given the small number of Vieques cases, the age was confirmed to ensure that all 

potential cases could be included.

How ATSDR Addressed the Study Findings

Health outcome data was not included in previous ATSDR reports about Vieques. This study’s results are 

now discussed in Chapter 4.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-66

Category: Health Outcome Data 

Date of Publication: March 2000

Title: Exploratory study of health and other conditions in 

Vieques

Author(s): Yadiris Lopez, and Crisarlin Carrosquillo

Affiliation: Scientific and Technical Services and the University 

of Puerto Rico Graduate School of Planning

Publication Status: Self-published

Peer Review Status: Unknown

Cited Previously by ATSDR: No

Study Findings

This document describes a cross sectional study of residents in four Vieques neighborhoods—Lujan, 

Puerto Rico Reconstruction Administration settlement (PRRA), Esperanza, and Santa Maria. Reportedly, 

fieldwork for this study occurred between April and November 2000.36 The authors attempted to 

include all residents in each neighborhood and allowed the head of a household—typically the 

matriarch—to provide proxy responses for all household members. Beyond the demographic, 

employment, and dietary habit information collected, the survey also gathered self-reported disease 

prevalence data. 

Cancer, heart disease, hypertension, diabetes, and asthma were self-reported at a higher prevalence 

than referent data from the main island of Puerto Rico. Specifically, the reported case rates were 1.18–

2.69 times the reported case rates from a 1994 Puerto Rico study. All data were self-reported or 

reported via proxy. No attempt was made to access medical records to validate the collected 

information. 

The four neighborhoods were collectively described as representative of the Vieques population. Lujan 

had 132 reported residents with a reported age range of 5–25 years, PRRA had 306 reported residents 

with a reported age range of 59–70 years, Esperanza had 388 reported residents, and Santa Maria had 

217 reported residents. 

How ATSDR Addressed the Study Findings

Health outcome data was not included in previous ATSDR reports about Vieques. This study’s results are 

now discussed in Chapter 4.

 

36 This time frame as reported appears inconsistent with the March 2000 publication date.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-67

Category: Health Outcome Data

Date of Publication: November 25, 2009

Title: Incidence and Mortality of Cancer in Vieques 1990–2004

Author(s): Nayda R. Figueroa, MD, MPH, Erick Suárez, PhD, 

Taina De La Torre, MS, Mariela Torres, MS, and Javier 

Perez, MPH,CTR

Affiliation: Commonwealth of Puerto Rico, Department of Health 

Publication Status: Self-published

Peer Review Status: None

Cited Previously by ATSDR: No

Study Findings

From 1973 to 1989, the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) 

Program in part funded the Puerto Rico cancer registry (PRCR). After 1989, the contract between the 

PRCR and SEER was not renewed, and until 1997, PRCR operated on local funding. In 1997, the PRCR 

applied for and received funding from the Centers for Disease Control and Prevention (CDC) through a 

cooperative agreement via the National Program of Cancer Registries. In calendar year 1998, beginning 

with cancer cases diagnoses, the PRCR provided data to the CDC .

In this report, cancer incidence and mortality in Vieques during 1990–2004 for the most common 

anatomical sites (i.e., breast, colorectal, cervical, oral cavity and pharynx, lung and bronchus, and 

prostate) and a few other cancers potentially associated with environmental exposures (i.e., liver and 

intrahepatic bile duct, kidney and renal pelvis, bladder, lymphoma and leukemia) were assessed for 

three periods (1990–1994, 1995-1999, and 2000–2004). Cancers were also assessed by sex where 

applicable. To present five-year cancer incidence and mortality rates is standard practice, as noted in 

publications such as SEER’s Cancer Statistics Review, the North American Association for Central Cancer 

Registries' Cancer in North America, and joint publications such as the United States Cancer Statistics. 

After age adjustments, the analysis identified increased cancer incidence in Vieques for some specific 

anatomical sites as well as in all cancers combined. Significant increases were identified in 1990–1994 

and 1995-1999. Statistically significant, age adjusted standardized incidence ratios (SIRs) with 

corresponding 95% confidence intervals (95% CIs) were identified for:

1990–1994

 Lung and bronchus for both sexes combined (SIR=2.34; 95%CI 1.36, 3.75 and ; 

 Lung and bronchus for men (SIR=2.43; 95%CI 1.25, 4.24); 

1995–1999
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-68

 All cancers for both sexes combined (SIR=1.26; 95% CI 1.08, 1.47)

 All cancers for men (SIR=1.31; 95% CI 1.07, 1.60)

 Prostate (SIR=1.53; 95%CI 1.09, 2.09).

After age adjustments, the analysis identified an increased cancer mortality in Vieques for some specific 

anatomical sites as well as for all cancers combined. Statistically significant, age adjusted standardized 

mortality ratios (SMRs) with corresponding 95% confidence intervals (95% CIs) were identified for:

1990 – 1994 - Colorectal cancer for women (SMR=2.75; 95% CI 1.11, 5.67)

1995 – 1999 – All cancers for both sexes combined (SMR=1.35; 95% CI 1.08, 1.67)

2000 – 2004 

All cancers for men (SMR=1.40; 95% CI 1.07, 1.80)

Prostate cancer (SMR=2.62; 95% CI 1.66. 3.93)

As mentioned briefly in the document and as confirmed by Dr. Figueroa (personal communication, July, 

2009), some follow up was necessary to identify cases in Vieques that were not processed uniformly 

with the rest of PR. One example relates to documentation of age for cases in the registry. For this 

assessment, on the island of Vieques all cases indicating residence had their ages confirmed. But this 

practice was not followed on the PR main island. If a case did not have a known age, it was omitted from 

any rate calculations. Given the small number of Vieques cases, the age was confirmed to ensure that all 

potential cases could be included.

How ATSDR Addressed the Study Findings

Health outcome data was not included in previous ATSDR reports about Vieques. This study’s results 

are now discussed in Chapter 4.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-69

Category: Environmental Data – Coral Reef Ecosystem 

Date of Publication: June 2002

Title: Ex-USS Killen Site Investigation and Biological 

Characterization, Vieques Island, Naval Station Roosevelt 

Roads, Puerto Rico

Author(s): Ken Deslarzes, Robert Nowajchik, and David Evans

Affiliation: Geo-Marine, Inc

Publication Status: Self-published

Peer Review Status: No

Cited Previously by ATSDR: Yes

Study Findings

In November 2001, marine scientists mapped the remains of the former USS Killen (in two pieces in 

Bahia Salina del Sur), and assessed the submerged aquatic vegetation, fish population, and coral 

population around the sunken vessel. Given the amount of superstructure missing from the Killen, the 

hypothesis was that the drums were used as ballast to redistribute the weight of the target ship. They 

also found that several of the drums had been sealed empty to provide buoyancy to certain of the ship’s

compartments. The submerged aquatic vegetation around the two areas was comparable to the control 

site and did not exhibit signs of environmental distress. The vessel supported fish and coral populations 

similar to the control site, and was not found to be negatively affecting the ecosystem. The study 

concluded that the sunken vessel was acting as a productive artificial reef habitat.

How ATSDR Addressed the Study Findings

ATSDR used the results of this study in the 2003 Fish and Shellfish Evaluation to address the Viequenses’ 

concerns about the former USS Killen and the drums associated with it. As part the agency’s evaluation 

of Vieques, a summary of the study was added to the section discussing the effects former military 

activities on Vieques have had on the surrounding marine environment (See Chapter 2, Section 2.1.4). 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-70

Category: Environmental Data – Coral Reefs 

Date of Publication: July 2008

Title: A Tale of Germs, Storms, and Bombs: Geomorphology and 

Coral Assemblage Structure at Vieques (Puerto Rico) 

Compared to St. Croix (U.S. Virgin Islands)

Author(s): Bernhard Riegl, Ryan P. Moyer, Brian K. Walker, 

Kevin Kohler, David Gilliam, and Richard E. Dodge

Affiliation: National Coral Reef Institute

Publication Status: Journal of Coastal Research 24(4):1008–1021

Peer Review Status: Yes

Cited Previously by ATSDR: No

Study Findings

This study compared the variability of coral assemblages of reef zones between Vieques and St. Croix to 

evaluate the differences and the influence of natural and manufactured factors. The researchers 

established 18 sites at Vieques (12 inside the former LIA and 6 in the former EMA) and 6 at St. Croix for 

evaluation of coral assemblage structure. No differences in living benthic coral reef cover or composition 

of coral assemblages between inside and outside the LIA were found at Vieques. Also, coral assemblages 

at Vieques and St. Croix were similar in composition and biotic coverage. The researchers considered the 

lack of differentiation within the coral communities of Vieques and between Vieques and St. Croix the 

most pronounced outcome of the study. Because the reefs at St. Croix were not in better condition than 

reefs at Vieques, the authors suggest that natural disturbances (disease and storms) had a greater 

impact on coral communities than former military bombing activities. 

How ATSDR Addressed the Study Findings

Because Viequenses are concerned about the effects that bombing activities have had on the marine 

environment, ATSDR reviewed this new study as part the agency’s evaluation of Vieques. A summary of 

the study was added to the section discussing ecological impacts to the coral reefs around Vieques (see 

Chapter 2, Section 2.1.4). 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-71

Category: Environmental Data – Fish and Shellfish 

Date of Publication: November 2001

Title: Field Data Summary, Vieques Fish Assessment, Vieques, 

Puerto Rico

Author(s): Daniel Cook, Steven Clapp, and Alan Humphrey 

Affiliation: Lockheed Martin/REAC and U.S. Environmental 

Protection Agency/Environmental Response Team

Publication Status: Self-published

Peer Review Status: No

Cited Previously by ATSDR: Yes

Study Findings

The U.S. Environmental Protection Agency’s Environmental Response Team (EPA/ERT) collected and 

analyzed 104 fish and 38 shellfish (representing 20 different edible species) from the coastal waters and 

near shore land on Vieques in July 2001. Fiddler crabs from the LIA were also collected. EPA/ERT caught 

fish and shellfish from five preferred fishing locations (north of the LIA, south of the LIA, south of 

Esperanza, north of Isabel Segunda, and west Vieques) as well as from a local fish market in Isabel 

Segunda. Several heavy metals were detected in the fish and shellfish. No explosive compounds were 

detected in the fish and shellfish, with the exception of low levels of cyclotetramethylene tetranitramine 

(HMX) and a chemical similar to cyclotrimethylene trinitramine (RDX)37 in fiddler crabs and a chemical 

similar to RDX in one trunkfish from the fish market. Because the fiddler crabs had not been rinsed prior 

to analysis, the detection may have been the result of soil contamination. Explosive compounds were 

not detected in any of the other 142 edible fish or shellfish samples. EPA/ERT statistically determined 

that the chemical concentrations in fish and shellfish collected from south of the LIA were similar to 

those collected from west Vieques. The divers qualitatively noted that the reefs were in good condition 

and the fish appeared healthy. They documented the presence of unexploded ordnance to the north 

and south of the LIA.

How ATSDR Addressed the Study Findings

EPA/ERT conducted the study to assist ATSDR with their evaluation of whether commonly consumed 

fish and shellfish from Vieques contain levels of heavy metals and explosives compounds that would 

adversely affect public health. The results of the study were thoroughly evaluated and discussed in the 

2003 Fish and Shellfish Evaluation. As part the agency’s evaluation of Vieques, a brief summary of the 

general reef conditions found during the study was added to the section discussing ecological impacts to 

the coral reefs around Vieques (See Chapter 2, Section 2.1.4). 

 

37 A conclusive identification could not be confirmed by the laboratory that conducted the analyses.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-72

Category: Environmental Data – Sea Life and Sediment

Date of Publication: May 2010

Title: An Ecological Characterization of the Marine Resources 

of Vieques, Puerto Rico Part II: Field Studies of Habitats, 

Nutrients, Contaminants, Fish, and Benthic Communities

Author(s): Bauer, L.J. and M.S. Kendal (eds.)

Affiliation: National Oceanic and Atmospheric Administration 

(NOAA)

Publication Status: Government Publication, NOAA

Peer Review Status: Yes

Cited Previously by ATSDR: No

Study Findings

The purpose of this study was to provide a spatially comprehensive characterization of the marine 

ecosystem surrounding Vieques. It builds on NOAA’s previous efforts by investigating fish fauna, benthic 

communities, nutrient levels, and chemical contaminants in the marine environment around Vieques. 

The data were grouped and analyzed according to former land use. The key findings are summarized 

below:

A stratified random design was used to select 75 sites for benthic and fish community surveys 

around Vieques. The researchers found that Vieques was similar in terms of benthic cover, total 

fish abundance, and biomass to other nearby locations (southwest Puerto Rico, St. Croix, and St. 

John). Differences in fish and benthic communities could not be conclusively linked to former 

land use patterns. 

A stratified random design was used to select 78 sites for sediment (lagoon and offshore) and 35 

sites for coral tissue sampling. The sediment and coral tissue samples were analyzed for 150 

chemical contaminants including metals, pesticides, and explosives. Overall, contaminant 

concentrations were below established sediment quality guidelines, sediments from lagoons 

typically had higher concentrations than offshore sites, and sediments had higher 

concentrations of trace and major elements than corals. Sediment samples analyzed for 14 

explosive compounds yielded no confirmed detections. DDT (at four sites) and chromium (at 

one site) were detected in sediment samples above established sediment quality guidelines. 

However, no sites had contaminant concentrations that were likely to affect sediment-dwelling 

biota. Sediment concentrations of polycyclic aromatic hydrocarbons were significantly higher in 

the land-use zone that included the former Naval Ammunition Support Detachment. The 

concentration of cadmium was significantly higher in the former LIA. 

Water samples from 40 stratified random designed sampling stations were analyzed for nitrate 

nitrite, silicate, orthophosphate, ammonium, urea, total nitrogen, and total phosphorus. No 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-73

evidence of anthropogenic over-enrichment of nutrients was discovered. Nutrient 

concentrations were generally low and similar in magnitude to those measured elsewhere in 

Puerto Rico. Nitrogen and phosphorus concentrations were below published threshold values 

considered threatening for macroalgal overgrowth on coral reef ecosystems. 

The authors concluded that there was little evidence of any difference in marine resources, nutrients, or 

contaminants around Vieques compared to other coral reef ecosystems in Puerto Rico and the U.S. 

Virgin Islands. The reef ecosystem appears to be shaped primarily by regional-scale processed rather 

than local factors. The results of the study supported neither of the following hypotheses: 1) naval 

activities negatively affected the marine environments around Vieques and 2) the lack of development 

on two-thirds of the island was a positive influence by preventing human activities documented 

elsewhere to be harmful to marine environments. 

How ATSDR Addressed the Study Findings

Because Viequenses are concerned about the effects that bombing activities have had on the marine 

environment, ATSDR reviewed this new study as part the agency’s evaluation of Vieques. The results of 

the heavy metal sampling in sediment and coral are discussed in Chapter 1, Section 1.3.3. A summary of 

the study was also added to the section discussing ecological impacts to the coral reefs around Vieques

(see Chapter 2, Section 2.1.4). ATSDR notes that the scope of the study was to characterize the entire 

marine ecosystem around Vieques; it was not intentionally directed toward characterizing the impact 

from bombing activities. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | A-74
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-1

Appendix B—Summaries of Previous ATSDR Documents

This appendix contains summaries of ATSDR’s previous documents evaluating environmental data 

related to Vieques. The appendix also includes summaries of two panel reviews funded by ATSDR – one 

concerning heart echocardiograms and the other concerning elemental hair analysis.

The question of peer reviews for public health assessments is often raised. Public health assessments 

are generally not peer reviewed; Congress specifically directed that “all studies and results of research 

conducted under this section (other than health assessments) shall be reported or adopted only after 

appropriate peer review.” See 42 U.S.C. §9604(i)(13) of the Comprehensive Environmental Response, 

Compensation, and Liability Act of 1980 (CERCLA or Superfund), as amended by the Superfund 

Amendments and Reauthorization Act of 1986 (SARA).

Although public health assessments are generally not peer reviewed, they are released for public 

comment. In addition, some public health assessments are in fact peer-reviewed. For those relevant 

Vieques public health assessments that were peer reviewed, this appendix notes the public comment 

date and the peer reviewers’ names.

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-3

Table of Contents

Isla de Vieques Bombing Range Public Health Assessment: Drinking Water Supplies and Groundwater B-5

Isla de Vieques Bombing Range Public Health Assessment: Soil Pathway ................................................B-8

Isla de Vieques Bombing Range Public Health Assessment: Fish and Shellfish.......................................B-10

Isla de Vieques Bombing Range Public Health Assessment: Air..............................................................B-12

Isla de Vieques Bombing Range Health Consultation: Land Crabs..........................................................B-14

Hair Analysis Panel Discussion: Exploring the State of the Science – June 2001.....................................B-15

Expert Review of the Vieques Heart Study..............................................................................................B-19

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-5

Category: Environmental Data − Drinking Water Supplies and 

Groundwater 

Publication Date: February 20, 2001: Public Health Assessment 

released for public comment; October 16, 2001: Final 

Public Health Assessment

Title: Isla de Vieques Bombing Range Public Health 

Assessment: Drinking Water Supplies and Groundwater

Author: ATSDR

Publication Status: Published after public comment and peer review

Peer Review Status: The document was technically reviewed by

Dr. Fernando Diaz-Barriga, Universidad 

Autonoma de San Luis Potosi, Mexico

Robert E. Faye, P.E., Robert E. Faye and 

Associates, Inc.

Hernan Horta Cruz, MS, Puerto Rico Department 

of Health (PRDOH), 

Mike Glogower, U.S. Environmental Protection 

Agency (EPA) Region II, 

Sigfredo Torres-Gonzales, U.S. Geological Survey 

(USGS)

A Vieques resident petitioned ATSDR to investigate whether contaminated groundwater might move 

from beneath the Live Impact Area (LIA) to the populated areas of Vieques. ATSDR studied the 

hydrogeology of the island and evaluated chemical levels in drinking water and in groundwater samples 

collected from Vieques wells and tanks. ATSDR thereafter concluded that 

The water from the current public water supply system is safe to drink

Most Vieques residents receive their drinking water through an underwater pipeline from the Puerto 

Rico mainland. In 1999 and 2000, the U.S. Environmental Protection Agency, the Puerto Rico 

Department of Health, and the U.S. Navy tested the public water supply system drinking water for 

volatile organic compounds, inorganic compounds, and explosive compounds. After an evaluation of the 

test results, ATSDR concluded that Navy activities did not affect the public drinking water supply and 

that the water was safe to drink. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-6

The water from most groundwater wells on the island is safe to drink

In the past, residents drew from groundwater wells in the Esperanza and Resolucion valleys. Smaller 

private wells in the residential areas also supplied drinking water. Many such wells currently provide 

supplementary drinking water whenever the mainland public water supply system is interrupted.

From 1995 to 2000, the U.S. Environmental Protection Agency, the Puerto Rico Department of Health, 

the U.S. Geological Survey, and the U.S. Navy sampled groundwater wells on the island for volatile 

organic compounds, inorganic compounds, pesticides, herbicides, polychlorinated biphenyls, and 

explosive compounds. Explosive compounds and their residues were not found in any of the wells. 

ATSDR evaluation included whether, for people drinking water from the wells, detected chemicals were 

at harmful levels.

ATSDR concluded that during public water supply interruptions, water from all but one of the wells was 

safe to drink. But ATSDR also found that the groundwater wells had naturally high sodium content—thus 

residents on sodium-restricted diets were advised to consider limiting their intake of water from the 

island’s groundwater wells. One private well (Well 3-7) also showed high levels of nitrates/nitrites. Thus 

the water from Well 3-7 was not safe to drink, especially for children and pregnant women. The Puerto 

Rico Department of Health issued an appropriate advisory, and the department’s staff personally 

informed residents that water from Well 3-7 was not safe. Given Vieques hydrogeology, ATSDR did not 

believe that contamination was a consequence of bombing range activities; rather, it was in all 

likelihood the result of area agricultural activities or septic systems.

Vieques Island’s geology and topography prevent groundwater movement from the Live 

Impact Area into the area where groundwater wells are located

ATSDR evaluated the hydrogeology of the island to determine whether hazardous substances from the 

Live Impact Area could groundwater-migrate to the drinking water wells area. ATSDR determined that 

the wells were within isolated aquifers and therefore not geologically connected to the groundwater on 

the island’s eastern end. In addition, between the Live Impact Area and the wells’ location, the island’s 

bedrock and westward topography sloped upward. Thus rather than migrating toward the wells, 

groundwater at the Live Impact Area moved slowly downhill toward the lagoons and, eventually, toward 

the ocean.

If good sanitation practices are followed, water from rainfall collection systems is safe to 

drink

Because no sampling studies characterized the quality of water in rainfall collection systems on Vieques, 

no site-specific sampling data were available on which to base firm conclusions. Nevertheless, if 

accepted sanitation practices were followed, ATSDR expected rainfall collection systems on Vieques 

would provide clean water that posed no health hazards.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-7

In the past, Vieques water was safe to drink

In 1978, the Navy reported very low levels of explosive compounds in drinking water samples from 

Vieques. The laboratory that analyzed the water samples stated some uncertainty in the results. ATSDR 

reviewed those data, as well as the sampling and analytical procedures, to evaluate whether those 

reported detections posed a potential health hazard. To be protective of public health, ATSDR analyzed 

the results assuming that the explosive compounds were present. ATSDR concluded that the 

concentrations reported were well below harmful levels. The water did not pose a health hazard to 

anyone drinking it in the past. And recent analyses of drinking water samples using updated sampling 

and analysis methodologies did not detect any explosive-related contamination.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-8

Category: Environmental Data – Soil

Publication Date: October 23, 2001 – Public Health Assessment 

released for public comment 

February 7, 2003 – Final Public Health Assessment

Title: Isla de Vieques Bombing Range Public Health 

Assessment: Soil Pathway 

Author: ATSDR

Publication Status: Published after public comment and peer review

Peer Review Status: The document was technically reviewed by

David Smith, USGS

Sigfredo Torres-Gonzalez, USGS

Rufus Chaney, Ph.D., U.S. Department of 

Agriculture (USDA)

Community members expressed concern that contaminants generated by bombing and other Navy 

training activities might have been windborne from the Live Impact Area and deposited on soils of 

Vieques residential areas. To address this concern, ATSDR evaluated roughly 600 soil samples collected 

by the U.S. Geologic Survey, the Puerto Rico Department of Natural Resources, the U.S. Navy, and 

Servicios Científicos y Téchnicos, Inc. ATSDR analyzed the samples for metals, other inorganic 

compounds, and explosive compounds, and concluded that

Residents of Vieques are not exposed to harmful levels of chemicals in the soil.

ATSDR compared the levels of chemicals found in Vieques soils to levels public health professionals

consider safe. ATSDR also conducted detailed analyses to determine the amount of chemicals to which 

people were expected to be exposed over a lifetime. The analyses showed that for either adults or 

children living on Vieques, incidental ingestion of soil or contact with soil would not result in harmful 

health effects.

The protestors who lived on the Live Impact Area for a year were not exposed to harmful 

levels of chemicals in the soil. 

From April 1999 to May 2000, to protest the U.S. Navy’s presence on Vieques, adults and children 

camped in the Live Impact Area. The Navy and Servicios Científicos y Téchnicos, Inc., collected soil 

samples from the areas where the protestors encamped. ATSDR analyzed the data and determined that 

for anyone incidentally ingesting or touching the soil, all of the chemicals were at levels below those 

that might cause harmful health effects.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-9

In comparison with soil elsewhere in the region, some of the metals detected in Vieques soil 

were moderately elevated.

ATSDR compared Vieques soil quality with sediment on the Puerto Rico mainland and with soil in the 

United States. ATSDR found that the maximum level of some of the metals detected in Vieques soil was 

moderately elevated when compared with soil in Puerto Rico and in the United States. ATSDR also 

analyzed the chemical characteristics of soil on Vieques to determine whether metals were at 

unnaturally high levels. To do this, ATSDR grouped soil samples throughout the island according to their 

underlying rock (the geologic units), and compared the general chemical characteristics of those soils. 

ATSDR found that the Vieques soils were strongly influenced by the type of rock from which they were 

formed—in other words, soils developed on different underlying rock had different levels of metals. The 

levels of metals detected on Vieques were consistent with those normally found in soils underlain by the 

type of rock found on Vieques (e.g., volcanic rocks) and were not at levels of health concern.

The concentrations of metals in the soils of the Live Impact Area appeared moderately 

elevated but not at harmful levels.

According to ATSDR’s analysis, Live Impact Area soils appeared to have been influenced by Navy training 

activities and contained elevated metals levels. ATSDR determined, however, that the metals 

concentrations in the soil were not at harmful levels.

ATSDR’s spatial analysis showed that metals were apparently not moving from the Live 

Impact Area into Vieques residential areas.

ATSDR examined the soil data for spatial trends that might show movement of metals from the Live 

Impact Area to the residential areas of Vieques (i.e., a pattern of high to medium to low concentrations 

from east to west). To do this, ATSDR created spatial maps showing the locations of metal 

concentrations detected on Vieques. None of the spatial maps showed any patterns beginning with high 

concentrations in the Live Impact Area and decreasing concentrations tapering off to the western parts 

of the island. Thus the soil data collected from across the island indicated that contaminants from the 

Live Impact Area were not air-transported in substantial quantities and deposited in the island’s 

residential areas. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-10

Category: Environmental Data – Fish and Shellfish 

Publication Date: November 14, 2002 – Public Health Assessment 

released for public comment 

June 27, 2003 – Final Public Health Assessment

Title: Isla de Vieques Bombing Range Public Health 

Assessment: Fish and Shellfish 

Author: ATSDR

Publication Status: Published after public comment and peer review

Peer Review Status: The document was technically reviewed by 

Felix Lopez, U.S. Fish and Wildlife Service (FWS)

Carlos Ramos, U.S.EPA Region II

Jerry Stober, U.S.EPA Region IV

Previous studies reported elevated levels of metals in fish and shellfish that are eaten by the residents of 

Vieques. To address this concern, ATSDR worked with the U.S. Environmental Protection Agency’s 

Environmental Response Team to collect and analyze fish and shellfish from the coastal waters and 

near-shore land on Vieques to determine whether fish and shellfish muscle tissues contain levels of 

metals and explosive compounds that would be harmful to human health.

From July 16th to 20th, 2001, fish and shellfish were collected from six locations on Vieques. ATSDR 

decided to collect grouper, snapper, parrotfish, grunt, goatfish, blue land crab, spiny lobster, and queen 

conch because they were identified by several sources as types of seafood that are commonly caught 

and eaten. These fish and shellfish were collected from reefs and near shore areas at the following six 

locations: (1) north of the Live Impact Area, (2) south of the Live Impact Area, near a sunken Navy vessel, 

(3) south of Esperanza, (4) north of Isabel Segunda, (5) a fish market in Isabel Segunda, and (6) west of 

the Laguna Kiani Conservation Zone on the west end of Vieques. Fillet and muscle tissues were analyzed 

for metals and explosive compounds. All sampling and analysis procedures were conducted in 

accordance with established U.S. Environmental Protection Agency protocols.

During the sampling event, the divers noted that all sample locations supported diverse, healthy 

populations of marine organisms and that all reefs were in good condition. They also noted that, with 

very few exceptions, the organisms collected appeared to be healthy.

ATSDR reached the following conclusions:

 Explosive compounds were not detected in any of the edible fish and shellfish from Vieques.

 Metals were detected in the fish and shellfish from Vieques; however, the levels were too low to 

cause harmful health effects for people eating the seafood.

 It is safe to eat fish and shellfish from Vieques every day.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-11

According to a local consumption study, almost half of the residents of Vieques eat seafood one or two 

times a week. However, some people responded that they eat seafood five or more times a week. To be 

protective of all residents, ATSDR estimated exposure by determining the amount of metals people 

would most likely be exposed to over their lifetime if they ate fish or shellfish every day for 70 years. 

ATSDR then compared the levels to those that are considered to be safe by public health professionals. 

ATSDR found that it is safe to eat a variety of fish and shellfish from Vieques on a daily basis.

Because of ATSDR’s current evaluation of Vieques, some of these conclusions have changed. Please see 

Chapter 9 for new conclusions and recommendations concerning fish and shellfish.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-12

Category: Environmental Data – Air 

Publication Date: November 22, 2002 – Public Health Assessment 

released for public comment 

August 26, 2003 – Final Public Health Assessment

Title: Isla de Vieques Bombing Range Public Health 

Assessment: Air 

Author: ATSDR

Publication Status: Published after public comment and peer review

Peer Review Status: See footnote #38

Several Vieques residents asked ATSDR if the air on the island was safe to breathe. The residents were 

most concerned about contaminants released into the air during the Navy’s military training exercises. 

These concerns included the Navy’s past live bombing exercises as well as the more recent practice 

bombing exercises. The residents also had questions about whether contaminated dusts from the 

bombing range might blow into their neighborhoods. 

ATSDR concluded that

Given the results of ATSDR’s modeling analysis, the Navy’s “live bombing” exercises did not 

pose a health hazard to residents.

Three air-sampling studies were conducted during the time when the Navy used live bombs on Vieques. 

The Puerto Rico Environmental Quality Board conducted two of these studies, and the Navy conducted 

the other. None of the measurements in these studies found air pollution to be at levels of health 

concern. However, because original documentation of these studies has not been located, ATSDR could 

not rest its health conclusions on these studies alone.

ATSDR estimated air quality impacts from live bombs using a modeling analysis. This analysis considered 

nearly 100 different contaminants that are known to be released to the air when ordnance explodes. 

The modeling analysis found that chemicals released to the air in smoke by the bombs dispersed to 

extremely low levels as the smoke traveled from the bombing range toward where people live. For most 

contaminants, the predicted air quality impacts where residents live were so low that even highly 

sensitive air sampling devices would likely not be able to measure them. In the case of particulate 

matter, for example, emissions from live bombing exercises were predicted to account for less than 1 

percent of the concentration of particulate matter currently measured in the residential areas of 

Vieques. This comparison suggests that emissions from the bombing range have extremely small 

impacts on the air quality in the residential areas of Vieques. Based on this modeling analysis, ATSDR 

concluded that emissions from live bombing exercises did not cause air pollution to reach levels known 

to be associated with health effects.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-13

The Navy’s practice bombing exercises did not pose a health hazard to residents.

From May 2000 through May 2003, the Navy’s military training exercises were conducted with so-called 

practice bombs. On days when practice bombs fell on the bombing range, the Puerto Rico 

Environmental Quality Board collected more than 50 particulate matter samples. In every sample the 

particulate matter levels were lower than health concern levels. In fact, in the residential part of the 

island no clear relationship appeared between the number of practice bombs dropped and the levels of 

air pollution measured. Using these observations and estimating air concentrations of other 

contaminants, ATSDR found that on days when practice bombing occurred, levels of air pollution did not 

present a health hazard to the island’s residents.

Wind-blown dust from the bombing range does not pose a health hazard to residents.

The air quality effects of windborne dust are typically evaluated by measuring the levels of particulate 

matter in the air. The term “particulate matter” refers to solid particles and liquid droplets in the air that 

we breathe. For the last 3 years, the Puerto Rico Environmental Quality Board has measured levels of 

particulate matter at two locations in Vieques residential areas. By the time the ATSDR air evaluation 

was complete, nearly 450 air samples had been collected. In every measurement, the amounts of 

particulate matter were well below health concern levels.38

 

38 The public health assessment in which this air sampling was discussed was presented at the Air and Waste 

Management Association's 96th Annual Conference and Exhibition in San Diego, June 22–26, 2003.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-14

Category: Environmental Data – Land Crab 

Publication Date: February 22, 2006 – Final Health Consultation

Title: Isla de Vieques Bombing Range Health Consultation: 

Land Crabs 

Author: ATSDR

Publication Status: Self-Published

Peer Review Status: None

The National Oceanic and Atmospheric Administration (NOAA) asked ATSDR to determine whether 

eating land crabs from various Vieques locations was safe. In June 2005, NOAA collected land crabs 

(Cardisoma guanhumi) from 14 locations (13 on Vieques and one on the Puerto Rico mainland). The 

crabs were analyzed for explosive compounds, polychlorinated biphenyls (PCBs), organochlorine 

pesticides, and trace elements. After reviewing the analyses, ATSDR concluded that

Land crabs are safe to eat

The levels of PCBs, organochlorine pesticides, and trace elements found in land crabs were much lower 

than levels reported to cause harmful health effects. The levels were also below the U.S. Food and Drug 

Administration (USFDA) regulatory limit for shellfish consumption. Only a few land crab samples 

contained PCBs and pesticides, indicating these chemicals were not widespread. ATSDR did not expect 

harmful health effects to occur in people who ate Vieques land crabs.

Children should not eat the land crab’s internal organs

Because of the amount of copper in land crab internal organs, children who ate those internal organs 

could experience stomach issues. As for the land crab’s muscle meat, children can safely eat that every 

day. Prudent public health practice would dictate, however, that children reduce their exposure to 

copper by not eating land crab internal organs.

Explosive compounds were not detected in any crab sample, and no association was found 

between land crab sampling location and contaminant levels 

In some of the areas sampled, land crabs contained higher average concentrations for certain chemicals 

than did land crabs in other areas. As for other chemicals, no remarkable differences were found 

between the locations. ATSDR found that people could safely eat every day one meal of land crab from 

any of the sampled locations.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-15

Category: Human Biomonitoring - Hair 

Publication Date: June 2001

Title: Hair Analysis Panel Discussion: Exploring the State of 

the Science – June 2001 

Author(s):

Robert Baratz, DDS, Ph.D., MD, Internal Medical 

Consultation Services, Inc.

Thomas Clarkson, Ph.D., University of Rochester

Michael Greenberg, MD, MPH, MCP, Hahnemann 

University

Michael Kosnett, MD, University of Colorado 

Health Sciences Center

Dan Pascal, Ph.D., Centers for Disease Control and 

Prevention

Sharon Seidel, Ph.D., California Department of 

Health Services

LuAnn White, Ph.D., Tulane School of Public 

Health

Publication Status: Published by ATSDR

Peer Review Status: Not applicable. Document is a panel discussion 

summary.

Executive Summary

In Atlanta, Georgia, on June 12 and 13, 2001, the Agency for Toxic Substances and Disease Registry 

(ATSDR) convened a seven-member panel to review and discuss the then-state of the science related to 

hair analysis; specifically, its use in assessing environmental exposures. ATSDR invited a cross-section of 

scientific experts in the fields of hair analysis, toxicology, and medicine to participate in 11⁄2 days of 

discussion on a variety of topics, including analytical methods, factors affecting the interpretation of 

analytical results, toxicologic considerations, and data gaps/research needs. 

Background

ATSDR convened this panel in response to 1) a then-growing number of inquiries from community 

members looking for assistance in interpreting hair analysis results, and 2) agency interest in learning 

more about the utility of hair analysis when evaluating exposures and health effects at hazardous waste 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-16

sites. The agency anticipated using the input received from this effort to develop guidance for agency 

health assessors on the use and interpretation of hair analysis data. 

The general questions that ATSDR sought to answer included

 For what substances are reliable hair analysis methods available? 

 When is it appropriate/inappropriate to consider hair analysis in assessing human exposures to 

environmental contamination? 

 What if any data gaps limit the interpretation and use of hair analysis in the assessment of 

environmental contaminants? 

This summary report presents the findings of the panel discussions. Principal discussion points are 

highlighted.

Discussions Overview

Panelists engaged in a series of discussions to address ATSDR's questions, pointing to several limitations 

with the then-state of knowledge on the usefulness of hair analysis in environmental exposure 

assessments. Discussions focused primarily on metals and trace elements in scalp hair. Panelists 

considered the distinct differences between using hair analysis to identify exposures (e.g., Is the 

substance reaching people? Does a competed pathway exist?) and using it to predict, diagnose, or treat 

disease (e.g., What do hair concentrations tell us about the likelihood of harmful health effects?). 

Panelists noted that the latter question pointed up the largest data gaps that then existed.

Although not required to reach consensus, the panelists did agree on the following summary statement 

related to the overall usefulness of hair analysis in evaluating environmental exposures:

For most substances, insufficient data were available that would allow the 

prediction of a health effect from the concentration of the substance in hair. 

The presence of a substance in hair may indicate exposure (both internal and 

external), but does not necessarily indicate the source of exposure.

For what substances are reliable hair analysis methods available? 

The group agreed that then-available laboratory methods could measure the levels of some 

environmental contaminants in hair. But to help ensure more accurate and reliable results, procedures 

needed to be standardized. That would include ensuring samples were collected by a trained person and 

would include but not be limited to establishing consistent sampling protocols, washing protocols, and 

quality control/quality assurance procedures. The panel further agreed that testing should be targeted 

to the specific element of interest.

When is it appropriate/inappropriate to consider hair analysis in assessing human exposures to 

environmental contamination?

In general, panelists agreed that before determining whether hair analysis was an appropriate 

assessment tool, assessors should consider 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-17

1. The exposure type and period. To understand the likelihood that a particular substance will be in 

the hair at the time of testing and to identify other exposure sources (e.g., hair treatments), take 

exposure histories.

2. Because the growth rate of hair is on average 12 centimeters per year, the panel concluded that 

hair analysis is not generally useful for evaluating very recent exposures or those longer ago 

than 1 year. Segmental analysis of hair (i.e., looking at concentration trends along the length of 

the hair) may have a role in documenting exposures over time (e.g., identification of a high-dose 

acute exposure). But this would require consideration on a subject-, substance-, and situationspecific basis.

3. The type of substance and its behavior in the body. Determine the biological plausibility that a 

particular substance will be present in hair and whether it is a marker of external contamination. 

4. The group agreed that little is known about the transfer kinetics of substances into hair.

5. The clinical relevance of a negative or positive finding. Determine the dose-response 

relationship, if any, between chemical concentrations in hair and target organ effects/illness. 

Without an understanding of a dose-response relationship, useful interpretations would not be 

possible. 

The panelists agreed that a relationship between contaminant concentrations in hair and any kind of 

measurable outcome has only been established for two substances: methyl mercury (e.g., the relation 

between maternal hair levels and observed developmental neurological abnormalities in offspring) and, 

to a limited extent, arsenic (e.g., segmental analysis for forensic analysis)—provided external 

contamination can be ruled out. Unique forensic settings for other substances could, however, provide 

similar relationships.

The group also indicated the need to evaluate, on a substance- and exposure-specific basis, the extent 

to which hair analysis might be more advantageous than other biological sampling, such as blood or 

urine analysis.

What if any data gaps limit the interpretation and use of hair analysis in the assessment of 

environmental contaminants?

The group identified several factors that limited the interpretation of even the most accurate, reliable, 

and reproducible laboratory results. These include

 The lack of reference (or background) ranges in which to frame the interpretation of results. In 

the absence of environmental exposures, assessors need a greater understanding of what is 

expected to be in hair to determine whether detected levels are elevated as a result of 

environmental releases, including possible geographical or regional differences in background 

levels.

 Difficulties in distinguishing endogenous (internal) from exogenous (external) contamination in 

hair. Making this distinction is important in evaluating internal doses of the substance of 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-18

interest. The group voiced different views on the effectiveness—before analysis—of washing 

hair to eliminate external contamination. Some felt that the then-current literature suggested 

no reliable washing method capable of separating external contamination from internal 

deposition of elements. One suggestion was that where possible, identifying metabolites (or 

other unique markers of internal exposure) for substances of interest was most helpful in 

distinguishing internal from external contamination.

 A lack of understanding of how and to what extent environmental contaminants are 

incorporated into the hair. At the time of the conference, little scientific information was 

available on the uptake or incorporation of environmental contaminants into hair. For metals or 

for environmentally relevant organic compounds, neither kinetic models nor metabolite data 

were known or fully understood.

 The lack of correlation between levels in hair and blood and other target tissues, as well as the 

lack of epidemiologic data linking substance-specific hair levels with adverse health effects.

Before hair analysis results could be used as a diagnostic tool or to predict health endpoints, 

these correlations must be understood. The panel noted that hair analysis was not likely to play 

a role in evaluations of some of the more common health concerns associated with hazardous 

waste sites (e.g., cancer, birth defects).

 Little information was available that was pertinent to the study of environmentally relevant 

organic compounds in hair.

 The panel recommended taking advantage of what was known about hair analysis in testing for 

drugs of abuse. 

The panelists encouraged standardization of sampling protocols and identified possible research areas. 

Yet hair analysis could only become a valid tool for any particular substance if research 

 Could establish better reference ranges, 

 Gained a better understanding of hair biology and pharmacokinetics, 

 Further explored possible dose-response relationships, 

 Established whether and when hair might serve as a better measure or predictor of disease than 

other biological samples (e.g., blood or urine), and 

 Learned more about organic compounds in hair.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-19

Category: Human Biomonitoring – Heart Study 

Publication Date: July 2001

Title: Expert Review of the Vieques Heart Study

Author(s):

Henry W. Blackburn, Jr., MD, University of 

Minnesota

Richard Devereux, MD, Cornell University

W. Dana Flanders, MD, D.Sc., MPH, Emory 

University

Miguel Ángel García-Fernández, MD, Hospital 

General Universitario Gregorio Marañón

Mauricio Hernández-Avila, MD, MPH, Ph.D., 

National Institute of Public Health

Elizabeth Ofili, MD, MPH, Morehouse School of 

Medicine

Dr. Manuel Posada de la Paz, Instituto de Salud 

Carlos III

Jesús Vargas-Barrón, MD, Instituto Nacional de 

Cardiología "Ignacio Chávez"

Publication Status: Published by ATSDR

Peer Review Status: Not applicable. Document is a record of peer review 

comments on the Ponce School of Medicine Heart 

Study

In January 2001, a pilot study comparing the echocardiograms of residents in Vieques and in Ponce 

Playa, Puerto Rico reported substantial valvular abnormalities and pericardial thickening in a large 

proportion of the Vieques residents—findings not seen among Ponce Playa residents. The possible 

abnormalities noted in the Vieques residents were attributed to "vibro-acoustic disease" (VAD), 

previously described in the medical literature by Portuguese investigators. VAD was said to occur as the 

result of noise and vibrations caused by naval exercises on the Island of Vieques. By Presidential 

directive, the Department of Health and Human Services investigated the issues raised by the study. The 

Department, in turn, referred this request to the Agency for Toxic Substances and Disease Registry 

(ATSDR), which was already investigating environmental public health issues in Vieques. 

Concurrent with this request, the Ponce School of Medicine (PSM) led by President and Dean Dr. Manuel 

Martínez Maldonado had begun a more focused study of possible cardiac abnormalities among Vieques 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-20

commercial fishers. This study sought to overcome methodological problems (e.g., sampling frame, lack 

of blinding) found in the earlier pilot study. On March 29–30, 2001, scientists from ATSDR and CDC met 

with the PSM investigators and agreed to invite the assistance of recognized practitioners and scientists 

in reviewing and interpreting the findings. The chosen reviewers were experts with international 

reputations in echocardiography and environmental or cardiovascular epidemiology. Because of its 

extensive experience, the echocardiography "core" laboratory at Mayo Clinic, directed by Dr. Jae K. Oh, 

was selected to review the echocardiograms.

Eight accomplished physician-scientists accepted invitations to participate. They were principally from 

academic institutions: four panelists were from U.S. universities, two from Mexico, and two from Spain. 

Half of the panelists were specialists in cardiology and echocardiography; others were epidemiologists. 

Additional meeting participants included personnel or consultants of PSM and ATSDR, Dr. Jae Oh of 

Mayo Clinic, and Dr. John Rullán, Secretary of Health of Puerto Rico. The meeting took place July 12–13, 

2001, in the Condado Plaza Hotel in San Juan. Dr. Martínez Maldonado and Dr. David Fleming, then 

Deputy Administrator of ATSDR, co-chaired. Participants reviewed the methods, results, and public 

health significance of the Vieques Heart Study, considering both PSM and Mayo Clinic data.

Dr. Martínez Maldonado and Dr. Carlos Ríos presented the Vieques Heart Study. The study objective was 

to determine any association between place of residence (Vieques or Ponce Playa) and morphological 

cardiovascular changes among commercial fishers.

Investigators sampled randomly from the lists of licensed commercial fishers from Vieques and from 

Ponce Playa and obtained 53 and 42 subjects from the two areas, respectively. Investigators measured 

height, weight, blood pressure, and other physical parameters, collected questionnaire data on 

demographics and possible confounders, and recorded subjects’ echocardiographic images. The 

echocardiograms were read “blindly” (i.e., without knowledge of the site of residence of the particular 

subject) for pericardial thickness by a group of several experienced PSM cardiologists, with caliper 

placement done by consensus and by using magnified images.

By PSM's measurements, the average pericardial thickness was slightly greater among Vieques fishers 

than among those from Ponce Playa (1.20 mm vs. 1.05 mm), and this difference was statistically 

significant (P = 0.03). The values for pericardial thickness measured by Mayo were within the same 

range as those measured by PSM, but did not achieve statistical significance when Vieques and Ponce 

fishers were compared (0.78 mm vs. 0.82 mm, respectively).

Panel Conclusions

The panel’s principal conclusion was that neither the Ponce Playa nor the Mayo readings contained 

information indicating a cardiac health problem in the fishers. The initial report of gross valvular 

pathology from the pilot study was not replicated. All reviewers agreed that no clinically relevant 

difference between Vieques and Ponce Playa subjects in pericardial thickness appeared, contrary to that 

reported in the pilot study. Moreover, neither the PSM nor the Mayo measurements showed any 

subject's pericardial thickness to be larger than 2 mm—a value the published literature considered in 

the upper limit of normal.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-21

The PSM study got generally high marks from the panelists regarding study design and statistical 

analysis. The sampling frame (lists of registered fishers) was regarded as appropriate, and reviewers 

generally felt that the response rate was adequate. The fact that reasonably clear-cut hypotheses had 

been developed beforehand largely obviated concerns about the problem of multiple comparisons. In 

general, panelists felt that the statistical tests used were appropriately chosen and employed. Panelists 

noted that echocardiographic readings were performed with appropriate blinding—including masking of 

dates—at both PSM and Mayo.

Summary Conclusion

The PSM study did not support a finding of cardiac pathology among Vieques commercial fishers. 

Because of the inability of trans-thoracic echocardiography to measure reliably the small differences 

found, the differences reported were likely due to measurement error (intrinsic to the technique, not 

the scientists who used it). This fact almost certainly accounts for the different results obtained when 

Mayo readings of pericardial thickness replaced PSM readings. 

The Vieques Heart Study represented a valuable contribution to scientific knowledge regarding the use 

of echocardiography. The panelists recommended the study’s publication in the peer-reviewed scientific 

literature.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | B-22
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-1

Appendix C—Peer Review Comments and ATSDR Responses

Table of Contents

Reviewer 1 .................................................................................................................................................C-5

Reviewer 2 ...............................................................................................................................................C-27

Reviewer 3 ...............................................................................................................................................C-33

Reviewer 4 ...............................................................................................................................................C-45

Reviewer 5 ...............................................................................................................................................C-65

Reviewer 6 ...............................................................................................................................................C-73

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-3

Introductory note: We submitted the same six questions to all six peer reviewers. Some of those 

questions included requests for comments to specific sub questions. We reproduce here 

each of the questions and sub questions we asked, each reviewer’s comments to the 

questions and sub questions, and our responses to their comments. Also, throughout our 

responses we refer to An Evaluation of Environmental, Biological, and Health Data from the 

Island of Vieques, Puerto Rico as simply “the Report.”
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-4
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-5

Reviewer 1

Overall, has ATSDR’s re-evaluation of public health issues associated with historical 

bombing exercises at Vieques been appropriate?

[Comment] The document as a whole is well written and relatively easy to follow. However, it suffers 

from a significant lack of consistent focus. While the ostensible question addressed by the document is 

whether the historical bombing exercises at Vieques have impacted public health, the document only 

sporadically focuses on those environmental health impacts that are specifically linked to the bombing 

and related military activities and often shifts focus to general environmental exposure and health 

considerations. Given the stated purpose of the review, one would expect that (at least for the 

environmental exposure/risk assessment portion of the review) there would be a logical structure that 

first defines the activities with a potential to impact public health, then identified the environmental 

contaminants that could be anticipated to result from those activities, then identified the 

environmental/biological media in which those contaminants are likely to be found, then presented the 

sampling results for those media and contaminants, and then compared those results to appropriate 

background data to make a determination of whether the exposures and potential exposures related to 

the sampling data were likely to be associated with the bombing and related activities. This logical 

progression should have been driven by one or two focused and explicit hypotheses to be tested. These 

hypotheses would take a form similar to, “The bombing and related military activities in Vieques have 

resulted in exposures to specific environmental contaminants above non-bombing-related background 

levels,” and “Elevated levels of the specific bombing-related contaminants pose a significantly elevated 

health risk to the exposed population.” While such an approach is implied in the review, it is only 

intermittently followed.

The review does refer to specific contaminants that were identified as resulting from the bombing 

activities - TNT, RDX, aluminum powder and “86 contaminants” including 15 metals that were identified 

in the BangBox test series. However, the relationship between the prevalence of these contaminants in 

the explosives and their likelihood of occurrence in environmental/biological media is not presented. 

This lack of prioritization not only makes hypothesis formulation and testing unclear, but also results in 

large uncertainty in distinguishing bombing-related contamination from background.

In contrast, the review seems to present information about environmental contamination that often 

appears to have no clear potential relationship with the bombing-related activities either with respect to 

the contaminants discussed or the spatial relationship between the impacted areas and the location of 

the samples. While this disconnect is not always the case in the review, it is the case sufficiently often 

that the reader loses the sense of a clear focus and context for the information presented. This is most 

notably the case in the sections on the Fish Pathway and Biomonitoring, although similar considerations 

also apply to the document’s treatment of other pathways. For example, in the Biomonitoring and Fish 

sampling portions of the document, there is a large focus on mercury. Given the extent of that focus, 

one could conclude that mercury contamination in fish and seafood is highly anticipated to result from 

the bombing-related activities and is a major focus of the environmental health impact associated with 

those activities. However, I have not found any place in the document where the relationship between 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-6

those activities and mercury contamination in the environment in general, or in marine species in 

particular, is established. A more focused and useful formulation and discussion of the potential impact 

of the bombing-related activities on mercury/methylmercury impact on the Vieques population could 

proceed along the following lines: 

 Is mercury/methylmercury contamination expected to be a major outcome of bombingrelated activities?

 If so, where would the impact be expected?

 Are the fish that are likely to be affected by bombing-related mercury, the fish that are 

consumed by Vieques residents?

 What are the consumption patterns of Vieques residents relative to the likely impacted 

fish?

 What is the background dietary exposure to methylmercury in Vieques (i.e., from nonimpacted fish) and how does it compare to the exposure from the likely impacted fish?

Given the ubiquity of at least low-level methylmercury contamination of fish worldwide, it should be 

anticipated that mercury would be found to some extent in all fish caught and/or consumed in Vieques. 

Furthermore, without a clear understanding of the background methylmercury exposure and the 

Vieques-specific fish consumption patterns, there is no clear way to distinguish the potential impact of 

bombing-related mercury exposure from the background in Vieques.

ATSDR generated few focused data specific to the assessment of bombing-related impacts in Vieques, 

but instead had to rely on existing data, much of which were not generated specifically for the purpose 

of this assessment and/or were not collected or analyzed in a systematic fashion designed for the 

appropriate hypothesis testing. This results in the classic situation where ATSDR largely ends up looking 

for its “keys” (i.e., relevant data) next to the lamppost because that’s where the light is. The quality of 

the overall assessment needs to be viewed in light of these limitations. Nonetheless, the use of the 

existing data without a clearer focus on the goal of the assessment and without a clear discrimination of 

the data relative to its quality and its relevance to the that goal has resulted in a document that is not 

clearly focused and often confusing in important parts.

ATSDR Response: All reviewers commented on contaminants that could be linked to 

military exercises on Vieques. We therefore provided additional clarification within the 

summary report and provided references from one section to other sections. For example, 

when we discussed substances measured in fish, we included references to explosive 

ordnance constituents and soil measurements. We also provided some perspective about 

those media constituent levels we expected to be higher than others. The Report (Executive 

Summary and Chapters 1; 2; 3; 6; and 9) has been revised to reflect greater clarity between 

substances found in the Viequense environment and those associated with activities related 

to military exercises involving live ordnance. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-7

ATSDR recognizes that the Report discusses both pathway-specific exposures to military 

exercise-related contaminants and to more general public health exposures. In that regard, 

ATSDR evaluated its previous work in response to continuing concerns about Viequenses’ 

general health. The above-referenced revisions do identify possible links found between 

substances in the environment and military exercises. While most of our data on 

contaminants in soil, water, air, and seafood are relatively recent, the releases that might or 

might not have contributed to them are historical.

To establish conclusive links or specific pathways between the two is impossible, except in 

the rare case where contaminants are uniquely associated with a site, such as RDX and TNT 

and bombing activities. This situation is not unique to Vieques—it is an inherent problem at 

any site where environmental contaminants have many potential sources, including some 

associated with past activities at that site.

Regarding mercury, scientists visited ATSDR in November 2009. They requested that ATSDR 

take another look at mercury levels in fish in light of the National Academy of Sciences’ 

statements on mercury’s harmful effects. We have added information to Chapter 2 to make 

this point more clearly.

Finally, ATSDR does not typically collect environmental samples. We rely on available data 

from other sources. 

Has ATSDR adequately addressed the pathways of human exposure to bombing rangespecific contaminants?

[Comment] ATSDR has identified and addressed the appropriate pathways of exposure. However, as 

discussed above, with obvious exceptions (e.g., TNT, RDX) it has not clearly identified those 

environmental contaminants that are bombing range-specific, nor has it identified the extent of 

exposures to contaminants in the environment that are potentially associated with bombing range 

activities. The exceptions to this are the air and soil contact pathways where ATSDR has made a strong 

case that significant exposure to bombing-related contaminants is unlikely.

ATSDR Response: We provided additional clarification within the Report and provided 

references from one section to other sections. We included references to explosive 

ordnance constituents when we discussed substances measured in fish. The Report 

(Executive Summary and Chapters 1; 2; 3; 6; and 9) has been revised to reflect greater clarity 

between substances found in the environment and those associated with military exercises 

involving live ordnance. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-8

Please include specific comments on:

Consumption of seafood from reefs near Vieques

[Comment] While the very limited data on contaminants unequivocally associated with the bombingrelated activities (e.g., TNT, RDX, Al) suggests that there is little or no significant accumulation of these 

chemicals in Vieques fish and little or no potential for accumulation, the great bulk of the assessment of 

consumption of bombing-related contaminants in fish is focused on mercury (Hg). As discussed above, 

there is no clear rationale provided for this focus. The nature and extent of the relationship between the 

bombing-related activities and mercury is not discussed and it is not even clear whether an 

accumulation of methylmercury (MeHg) in fish would be expected as a result of the bombing-related 

activities. I suspect that the focus on mercury in fish results more from the availability of data related to 

more general concerns about MeHg exposures than from a specific connection to the bombing-related 

activities.

ATSDR Response: Because scientists who visited ATSDR in November 2009 raised mercury 

in fish as a health concern, ATSDR reviewed its findings for mercury in fish. The scientists 

were concerned that ATSDR did not consider the National Academy of Sciences’ (NAS) 

evaluation of mercury in fish and the NAS’s Reference Dose recommendations to the 

U.S.EPA. Moreover, residents are still concerned that the fish they eat are contaminated 

with mercury. We have added information to Chapter 2 to make this point more clearly.

Iron, aluminum, copper, manganese, zinc, and lead are the metals that are most likely to be 

elevated in LIA soils from bombing activity, though other metals were also found in the 

bombs. It should be noted that all of these metals are also naturally present in the soils and 

rocks of Vieques (ATSDR 2003a, Learned 1973, USGS 1997 and 2001).

We also associated aluminum, iron, copper, and explosive compounds in some LIA-vicinity 

seafood with LIA-related military exercises. But these associations did not include mercury 

or other substances. Nonetheless the Report (Executive Summary and Chapters 1, 2, 3, 6,

and 9) has been revised to clarify any relationship between substances found in the 

Viequense environment and those associated with military exercises involving live ordnance.

[Comment continued] There were few data available on the fish actually consumed by Vieques 

residents. The primary source of species-specific consumption data appears to be the data collected by 

Dr. Caro in 2000. However, those data were based on a sample size of only 51 consumers. This sample 

size is unlikely to be representative of the population as a whole. No information is presented about the 

demographic representativeness of that sample, of the geographic location of the sample relative to the 

locations of concern, or of the fishing habits of the subjects relative to the population of Vieques in 

general. Furthermore, as presented, the data provide no information about the relative consumption 

frequency by species or of the variability in frequency among consumers. The document states that 

ATSDR “used multiple information sources to identify the preferred types of fish and shellfish for 

collection” including the data of Dr. Caro. However, the other sources are not specified and the manner 

in which the data in total were used is not specified. These data gaps make it very difficult to create a 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-9

reasonable model of fish consumption in Vieques and, in turn, to assess the exposure to contaminants in 

fish in general in Vieques, and especially in fish potentially impacted by bombing-related activities.

ATSDR Response: ATSDR agrees with the comments about Dr. Caro’s 2000 survey. This is 

why we supplemented Dr. Caro’s data with information gathered from 1) discussions with 

the residents of Vieques, 2) information provided in the Vieques Special Commission Report 

(Government of Puerto Rico 1999 as cited in Navy 2000b), 3) visits to local fish markets, and 

4) PRDOH’s 2006 report. These discussions confirmed Dr. Caro’s findings. Dr. Caro’s data 

suggested 34% of Viequenses ate fish more than 3–4 times a week. PRDOH’s more extensive 

and random 2004 survey supported these findings (PRDOH 2006). We added this fact to 

Chapter 2.

Yet to refine our exposure estimates from eating reef fish, we do need additional 

information. We know that a significant proportion of Viequenses eat fish regularly. Still, 

more information about Viequense dietary habits would be useful, such as the frequency of 

consumption by sex and age for

 Reef fish, ocean-going fish, and canned fish,

 Various fish species,

 Portion size, and

 Reef location.

This additional information would allow more refined dose estimates and subsequent risk 

evaluations. In any event, we have made changes in Chapter 2 to highlight the lack of 

information about frequency of fish consumption by species and that having this 

information would allow more refined estimates of dose and subsequent risk evaluations.

Use of biomonitoring tools to assess exposure to metals and other hazardous chemicals in 

blood, urine, or hair that are related to historical bombing exercises

[Comment] Biomonitoring of exposure is potentially a very powerful tool. However, the occurrence of 

contaminants in biological media integrates exposures from all sources. Thus, the interpretation of 

biomonitoring data relative to the exposure and public health implications for a specific population from 

a specific source is highly reliant on both the understanding of the sources of exposure and the 

background of the exposure from other sources in that population. The biomonitoring studies 

considered in the review have significant limitations for the assessment of the public health impact of 

the bombing-related activities. The sample sizes in the studies other than the PRDOH study were quite 

small (n = 30, 52), the relationship of the subjects to potential sources of the specific exposures in 

question were not presented, and there was no appropriate referent population from Vieques that 

could be used to distinguish background sources of exposure from bombing-related sources of 

exposure. Information about background levels of exposure were either from Puerto Rico, US-NHANES 

or from laboratory reference ranges. The relationship between the background exposures in the Puerto 

Rico and NHANEs data and those in Vieques were not discussed and the nature of the laboratory 

reference ranges was likewise not discussed. Furthermore, based on the ATSDR assessment of the 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-10

PRDOH study, the data were not finalized and were of uncertain reliability. Elevations of biomonitoring 

levels relative to the mean or median levels in a dataset are to be expected due to normal statistical 

variation. To interpret those elevations in an exposure context requires either a statistically valid 

reference population and/or a separate measure of exposure (e.g., air, soil, water, food) that is 

comparable in time and space to the biomonitoring data and that can be used to elucidate the exposure 

context of those elevated biomonitoring levels.

Much of the biomonitoring data was for mercury relative to methylmercury exposure from fish 

consumption. However, I was unable to discern information from those data that allowed levels of 

mercury in those data to be related to potential bombing-related exposure (or lack of exposures). In any 

fish-consuming population, one would expect to find measurable concentrations of mercury in hair and 

blood and it would not be surprising to find a fraction of the population with levels that exceeded the 

levels corresponding to the USEPA RfD. This would be the case for populations consuming store-bought 

fish caught in remote locations and for populations consuming locally caught fish. Elevated levels of 

mercury in such datasets cannot be attributed to specific sources of contamination without additional 

data: mercury levels in a comparable population without exposure to locally impacted fish; the specific 

types of fish consumed; the locations those fish were caught; and the sources of contamination in those 

sources.

ATSDR Response: We agree that the Vieques human biomonitoring studies are limited. We 

also agree that using biomonitoring data can be problematic, especially when attempting to 

determine whether residents have been exposed to contaminants in explosive ordnance. 

For clarification, we have made changes in Chapter 3. 

We dedicated a large portion of the Report to describing mercury exposures. Many of the 

Report details were absent from the original PHAs. We were concerned that such 

disproportionate discussion of mercury might lead reviewers to conclude that we found an 

association between mercury and military exercises on Vieques. On the contrary, our 

assessment focused only on that chemical exposure scenario posing the greatest human 

health risk. Chemical results for soil, air, water, and biota did not reveal extensive 

contamination. And biomonitoring studies are unlikely to reveal whether residents were or 

are exposed to contaminants from explosive ordnance. We clarified these conclusions by 

revising Chapters 1, 2, and 3. In summary, chemical results for soil, air, water, and biota did 

not reveal extensive site-related contamination. Soils from the LIA, however, were shown to 

contain metals above typically occurring background levels and some of these metals are 

associated with bombing activities (e.g., iron, copper zinc, and lead). None of the levels 

detected in soil are harmful to humans. Although biomonitoring is unlikely to establish any 

link between human biomonitoring data and military contaminants on Vieques, some 

biomonitoring might identify unusual exposures. We agree that for some exposures, no 

reliable, accepted biomonitoring detection/measurement methods are available. We further 

agree that all biomonitoring has some limitations.

Consumption of food (produce, meat, dairy, eggs) grown on the island
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-11

[Comment] Because endogenous mercury in hair and blood almost exclusively reflects methylmercury

exposure and because methylmercury exposure comes almost exclusively from fish/seafood 

consumption, mercury biomonitoring data (other than urine data) can be related to fish consumption 

even if the additional data needed to relate that fish consumption to a specific source of mercury are 

not available. For other contaminants, where there is a unique or nearly unique source of exposure, 

positive biomonitoring results for those contaminants can provide clear evidence of exposure to those 

sources. However, for the biomonitoring of contaminants with multiple sources of exposure, including 

all of the metals reported for biomonitoring results from Vieques residents, biomonitoring data without 

additional exposure context provide little or no useful information about specific sources of exposure. 

Furthermore, to relate reliably biomonitoring levels to exposure from single source or from a 

combination of discrete sources, there has to be a known and established relationship between the 

concentration of the contaminant in the given biological medium (e.g., hair) and the exposure to that 

contaminant. Not all media have a valid concentration-exposure relationship for a given contaminant. 

Specifically, cadmium (Cd), arsenic (As), nickel (Ni), antimony (Sb) and lead (Pb) in hair are, to the best of 

my knowledge, not established or directly interpretable biomarkers of exposure. 

For these reasons I do not believe that the biomonitoring data presented by ATSDR can be interpreted 

relative to exposure to produce grown on the island, much less to exposure to contaminants from the 

bombing-related activities through consumption of food grown on the island.

ATSDR Response: ATSDR agrees with the reviewer’s comment about the irrelevancy of the 

mercury exposure source when evaluating the association between mercury and seafood 

consumption. In summary, chemical results for soil, air, water, and biota did not reveal 

extensive site-related contamination. Soils from the LIA, however, were shown to contain 

metals above typically occurring background levels and some of these metals are associated 

with bombing activities (e.g., iron, copper zinc, and lead). None of the levels detected in soil 

are harmful to humans.

[Comment continued] With respect to the direct sampling of locally grown food, ATSDR correctly points 

out the limitations in much of the available data. These include sampling of inedible portions of food 

plants and sampling of non-food plants, lack of appropriate analytical standards, and lack of 

consideration of bioavailability. Considerable discussion is focused on the cadmium levels in pigeon 

peas. While I agree with ATSDR’s analysis of the potential health impact of consumption of the sampled 

peas, that discussion is presented without a context for the results. It is unclear how, if at all, the 

sampled peas reflect exposure to pigeon peas island-wide, or the extent to which pigeon peas figure in 

the diet of the Vieques population in general. For the peas in particular and for the sampled produce in 

general, there is no basis for connecting data on contaminant levels in those samples to the bombingrelated activity.

ATSDR Response: Text in Chapter 5, Section 5.2.2 has been modified to address the 

reviewer’s comments. At this time, no data (i.e., consumption survey or further info on 

intake of pigeon peas relative to total legumes) are available on consumption patterns. Thus 

for this preliminary analysis we used conservative assumptions that modeled high-end 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-12

intake rates. Further refinement of these exposure estimates could make them more 

realistic and more representative of the Viequense population.

ATSDR agrees with the lack of evidence to support any assertion of a viable transport 

pathway of metals contamination from the Live Impact Area to distant areas where food is 

grown. Any detected metals are more likely to reflect other sources, such as soil background 

concentration or some other local source. This is an important distinction; yet the 

community did cite food intake as a health concern. Thus as a public health measure we 

used available data to conduct a conservative, preliminary evaluation of this pathway. 

Exposure to air, soil, and water on Vieques

[Comment] My conclusions presented above for interpretation of biomonitoring data relative to locally 

grown food apply equally to exposures from air, soil, and water on Vieques.

With respect to direct assessment of the air pathway, this is the strongest section and the one most 

clearly relevant to assessment of the potential impact of the bombing-related activities. In lieu of real 

time air monitoring data, the modeling approaches evaluated by ATSDR are the best approach to 

assessing this pathway. The conclusions from these analyses are robust and clearly support a conclusion 

that the bombing-related activities did not result in a significant exposure to residential areas.

With respect to the assessment of bombing-related contaminants in soil, although the sampling of onsite soil was necessarily limited, the conclusions of little historical health risk to the on-site protestors 

appear reasonable. This conclusion is based on the observations that the samples were taken at relevant 

and representative areas, that the bombing-related activities appear to have been widespread in that 

part of the island, and that essentially none of the soil sampling results indicated significant risk with 

long or short-term exposure. With respect to the impact of the bombing-related activities on the more 

remote, residential areas, ATSDR is correct in pointing out that potential transport of contaminants from 

the bombing areas to the residential areas would only have occurred by the same pathways that would 

have resulted in residential inhalation exposure to those contaminants. Thus, the modeled lack of 

significant airborne contamination from the bombing sites at the residential areas likewise, indicates 

lack of deposition of those contaminants to residential soil.

With respect to the assessment of drinking water, the provision of drinking water through the pipeline 

system remote from the bombing locations ensures that there is no exposure through drinking water for 

the great majority of the Vieques population. The lack of clear data on the extent of private well water 

and rain collection basin use and the associated lack of data for the quality of those sources creates 

some uncertainty about exposure from drinking water. Nonetheless, the hydrogeologic findings 

regarding the direction of groundwater flow appear to preclude contamination of the relevant aquifers. 

However, there are no data presented to substantiate that claim and these would be helpful (e.g., 

groundwater flow contours).

ATSDR Response: Thank you for your comments. We have added a topographical map 

showing groundwater flow contours as Figure 1.3 in the Report.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-13

Does the Vieques summary report adequately present and describe the limitations and

uncertainty of assessing human exposure to bombing range-specific contaminants?

[Comment] For the most part, ATSDR appears to be aware of the limitations of the available data for 

assessing human exposure to the bombing-related contaminants. The consideration of the air exposure, 

although somewhat short on detail, appears to be both site-specific, and appropriate in scope. The 

drinking water data are largely straightforward and are presented with the appropriate limitations 

largely arising from uncertainties about the extent of private well use. For the other exposures, despite 

awareness of the limitations associated with those data, data of limited or doubtful relevance are 

presented and considered in the overall assessment. I believe that more stringent criteria for inclusion 

of data in the review would have been appropriate for those exposures. In addition, particularly, in the 

sections on fish consumption and biomonitoring, ATSDR seems to repeatedly lose sight of the distinction 

between exposure to contaminants in general and exposure to contaminants specifically arising from 

the bombing-related activities. Specific instances of these points are presented in my text-specific 

comments.

ATSDR Response: As for the specific example of mercury, visiting scientists in November 

2009 requested that ATSDR review again its findings on mercury levels in fish, especially in 

light of the National Academy of Sciences’ statements on mercury’s harmful effects. As 

stated, the disproportionate focus on mercury might mislead reviewers into concluding that 

we found an association between mercury and the military exercises on Vieques. We could 

not show an association. On the contrary, in our assessment we focused heavily on the 

chemical exposure scenario that posed the greatest risk. Chemical results for soil, air, water, 

and biota did not reveal any such extensive mercury contamination. 

Describing all the environmental and health data available for Vieques is important—even 

when some of the data could not be verified or validated. The hair data results were 

presented for numerous metals. Some scientists believed the data were valid and drew 

conclusions from them. We described the limitations of these data in detail, pointing out the 

inability to distinguish between external contact and internal ingestion for most metals, 

except mercury. To this extent, ATSDR has attempted to report fairly the available data and 

to provide insight into their usability in making health decisions. In our conclusions and 

recommendations the data that could not be verified or validated were either not used 

(e.g., metals in hair, except mercury) or were used qualitatively (e.g., arsenic in urine 

reported in a Webinar).

All reviewers commented on Report discussions about possible links between 

contamination and the military exercises on Vieques. We thus provided additional 

clarification within the Report and provided references from one section to other sections. 

For example, when we discussed substances measured in fish, we included references to the 

explosive ordnance constituents and soil measurements. We also provided some 

perspective about various media constituents we expected to be higher than others. The 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-14

Report (Executive Summary and Chapters 1, 2, 3, 6 and 9) has been revised to clarify further 

those substances found in the environment and those associated with military exercises. 

In that regard, ATSDR recognizes the Report discusses both pathway-specific exposures to 

explosive-ordnance contaminants and more general public health exposures. This resulted 

from the request ATSDR received to review its previous work in light of Viequenses’ general 

health concerns. The revisions referenced above provide information on possible links 

between substances found in the environment and military exercises on Vieques. Yet to 

prove links or specific pathways between current detections and historical releases of 

contaminants from multiple potential sources is impossible. This is not a Vieques-specific 

problem—it is inherent at many sites where historical activities possibly resulted in 

environmental contamination.

Are independent studies utilized appropriately in the determination of potential health 

hazards?

[Comment] As indicated above, many of the independent studies were not conducted specifically to 

address the issue of the impact of the bombing-related activities. Some of the other studies that 

attempted to focus more directly on those activities were poorly designed or too limited in scope to be 

useful. ATSDR did not set a particularly high standard for discriminating among those studies in terms of 

incorporating data into its overall assessment. To some extent this is understandable given the necessity 

of addressing the communities concern and the limited pool of data with which to work. However, the 

net effect is one of a very mixed and loosely woven patch quilt of data sources. I address more specific 

comments below.

ATSDR response: We agree that the data are of varying quality, and we described their 

limitations. That said, only in very few instances did poor data underlie potential exposure 

assessments. Mercury in some fish—the public exposure scenario that posed the greatest 

health risk— was based on very high quality data. But even those data were limited. 

In response to the concerns about independent studies, it is important to describe all the 

environmental and health data that are available for Vieques. And this is true even when 

some of the data might be questionable. For instance, hair data results were presented for 

numerous metals. Some scientists believed these data were valid and drew conclusions on 

them. But ATSDR described the limitations of these data in detail. We pointed out the 

inability to distinguish between external contact and internal ingestion for most metals, 

except mercury. To this extent, ATSDR has attempted to report fairly the available data and 

to provide insight into their usability in making health decisions. In our conclusions and 

recommendations, these questionable data were either not used (e.g., metals in hair, except 

mercury) or were used qualitatively (e.g., arsenic in urine reported in a Webinar).

On the basis of ATSDR’s re-evaluation of historical bombing activities in the Vieques 

summary report, has ATSDR reached the appropriate conclusions and recommendations?

[Comment]
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-15

Fish pathway. I believe that the conclusions about mercury (Hg) levels by species and the health risk 

(relative to the methylmercury RfD) of consuming those fish at given rates of consumption are 

appropriate. Nonetheless, the connection between those conclusions and the impact of the bombingrelated activities remains a salient gap. I therefore agree with ATSDR’s conclusion that, “ATSDR cannot 

be certain of the extent that military activities did or did not contribute to the mercury levels found in 

fish.” However, given this conclusion, the discussion of methylmercury (MeHg) exposure from fish 

consumption in Vieques is likely to be misleading as a connection to the bombing-related activities is 

implied by that discussion.

ATSDR Response: We agree that the mercury discussions are extensive. We further agree 

that some readers might assume that mercury is related to explosive ordnance used during 

military exercises on Vieques. We clarified this possible misconception by revising Chapters 

1, 2, and 3. 

[Comment continued]

Biomonitoring. ATSDR did not actually reach conclusions regarding the biomonitoring or its relationship 

to the bombing-related activities. Other than to express caution about the use of biomonitoring using 

hair due to potential exogenous contamination (and not, however, because of the lack of a clear 

relationship between endogenous hair concentration and internal exposure as discussed above), ATSDR 

merely reiterated the conclusions of the individual investigators and did not attempt and overall 

synthesis. I believe that the appropriate conclusion is that the biomonitoring results do not permit any 

conclusions about exposure to the bombing-related contaminants.

ATSDR Response: We agree. Biomonitoring studies do not reveal whether residents were or 

are exposed to contaminants from live ordnance used during military exercises. We clarified 

this point by revising Chapter 3.

[Comment continued]

Health Outcome Data. Here too, ATSDR did not state clear conclusions about the relationship between 

the health outcomes data and the bombing-related activities. I agree, however, with the ATSDR’s 

conclusions about the methodological limitations of the Vieques disease incidence data.

ATSDR Response: Thank you for your comment. ATSDR did not state clear conclusions about 

any potential relationship due to the various methodological limitations in the limited, 

historical work.

[Comment continued]

Local Produce and Livestock Pathway. I agree with ATSDR’s overall conclusion for this area that, “ 

Currently available plant and livestock data are not adequate to evaluate thoroughly the extent of 

exposure to heavy metals in people who eat locally grown Vieques produce.” I also agree with the 

conclusion that (as discussed above) the conclusions for the air pathway would appear to preclude 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-16

significant off-site contamination of produce either by direct deposition onto plants, or deposition to soil 

followed by uptake by plants.

ATSDR Response: Thank you for your comment.

[Comment continued]

Air Pathway. I agree with ATSDR’s conclusion that “...airborne contaminants from historic uses of the 

Vieques Naval Training Range would have been essentially nondetectable in the residential areas of 

Vieques and unlikely to have resulted in harmful effects.”

ATSDR Response: Thank you for your comment.

[Comment continued]

Soil Pathway. I agree with ATSDR’s conclusion that, “Those who occupied the LIA from 1999–2000 were 

not at increased risk of adverse health effects from exposure to surface soil contaminants.” I also agree 

with the conclusion that, “Limited available data from other locations and air pathway considerations 

suggest that the military exercises in the LIA did not result in current contamination of residential soils 

with inorganic or explosive compounds at levels considered harmful,” and the related conclusion that, 

“Modeling described in the air pathway discussion has suggested that airborne transport of 

contaminants during past military exercises would not have been heavy enough to have affected soils in 

the island’s residential area.” It is not clear to me that the additional qualifiers that appear in the 

Chapter 9 conclusions are necessary.

ATSDR Response: Thank you for your comment. Because we wanted to identify clearly all 

possible uncertainties regarding our evaluation, we kept the qualifiers.

[Comment continued]

Drinking Water Pathway. I agree with ATSDR’s conclusion that consumption of the pipeline source of 

drinking water precludes exposure to drinking water contaminants from the bombing-related activities. I 

am somewhat confused, however, by the apparent contradiction between ATSDR’s conclusion on the 

one hand about the direction of groundwater flow precluding groundwater contamination westward of 

the bombing sites, and its conclusion on the other hand that an insufficient number of wells have been 

sampled to draw firm conclusions about the potential impact of bombing-related activities on drinking 

water wells.

ATSDR Response: We added clarifying text to Chapter 8, Section 8.3.1.2. Our evaluation 

indicates that bombing activities on Vieques would not affect the former drinking wells. Still, 

limited sampling in the 1970s showed two detections of explosives; thus we could not 

exclude the possibility of an unknown, past mechanism. But even conceding that the 

contaminants might have been extant in the past, they have not been detected in recent 

years.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-17

Select the appropriate category below:

List recommended changes (or reasons for not recommending)

o Recommend ( )

o Recommend with Required Changes (X)

o Not Recommended ( )

Additional Questions:

Are there any comments on ATSDR's peer review process?

No comment from the reviewer.

Are there any other comments?

Text-Specific Comments

Pg. 15, last par. - The FDA’s risk benefit analysis has only been circulated in draft form and has been 

broadly criticized by the USEPA. While there is clearly a risk benefit trade off with respect to fish 

consumption and mercury (Hg), there is no clear basis for quantifying the nature of that trade-off at this 

time.

ATSDR Response. We agree. Thank you for the comment

[Comment continued]

Pg. 17, par. 2 - “...the authors concluded that the results show that mercury concentrations are higher in 

fish from markets in Vieques compared with the control population from Parquera.” There is no 

statistical analysis presented to support this assertion. Furthermore, the comparison between Vieques 

and Esperanza does not indicate a likely significant difference. Without more information and contextual 

description, no conclusion can be drawn from these data.

ATSDR Response: This conclusion is based on averages calculated much differently than 

proposed by the U.S.EPA or FDA. Some of Dr. Caro’s conclusions were based on two 

samples, analyzed at separate times, and treating a nondetected value differently from that 

suggested by U.S.EPA. Of the few species that had sufficient samples for comparison (hind, 

parrot, and grunt), only grunt had statistically higher levels of mercury in Vieques. The 

highest mercury level found by Dr. Caro of 0.052 ppm was found in Parguerra and this was 

37% higher than the highest level found in Vieques. Complete data tables from Dr. Caro's 

appendix 10 have been added to Chapter 2 (see Table 2-2). 

[Comment continued]

Table 2-2 - This table requires sample numbers (n’s) to be valid.

ATSDR Response: We have added the sample numbers to Table 2-2.

[Comment continued]
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-18

Pg. 18, par. 1 - What is the source of the fish referred to here as “market fish?”

ATSDR Response: In Chapter 2, Section 2.2.1, we clarified that the market fish in this 

statement refers to Vieques fish markets.

[Comment continued]

Pg. 22, par. 1 - The goal here is to characterize consumption, not the species per se. Therefore, 

discussion about combining species should have been driven by consideration of which species were 

most commonly consumed.

ATSDR Response: Insufficient data are available to evaluate contaminant levels by species; 

we had to combine fish by families. In most cases, this resulted in data by genus rather than 

by species. Grouping fish by families did allow an evaluation of mercury levels in grunt, hind, 

and snapper. 

[Comment continued]

Last paragraph - If, as stated “...the data were not adequate for comparison by species,” then why does 

the preceding discussion compare grunt/hind with other fish.?

ATSDR Response: We have analyzed the data further and found that some species could be 

compared. Previously we grouped species in each family (e.g., hind, grunt, snapper) 

together to compare concentrations at locations. We have since determined that some 

species (e.g., rock hind and red hind) can be individually compared. These comparisons are 

described in Chapter 2, Section2.5.

[Comment continued] Pg. 26, #5 - There is no basis for this assertion. There is no LOAEL or NOAEL for 

MeHg

ATSDR Response: We have modified the sentence.

[Comment continued]

Last paragraph - The NAS report did not support a lowest observed effect level (LOAEL) for MeHg. Pg. 

27, par. 1 - The notion that the NAS report identified a LOAEL or (as stated here, a “lowest level known 

to cause harmful effects,” is incorrect. The value endorsed by the NAS report and ultimately adopted by 

the USEPA is based on benchmark dose modeling. It is an estimate of an effect level (i.e., doubling of the 

population in the lowest 5% of performance) not a lowest or no-effect level. Pg. 28, par. 3 - See language 

in the previous comment regarding the nature of the basis for the USEPA MeHg RfD.

ATSDR Response: We have modified the language in Chapter2, Section 2.2.5 to be 

consistent with terminology used by the NAS and USEPA.

[Comment continued]
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-19

Pg. 29, second bullet – “... whether eating those fish and shellfish could make people sick...” This is not 

the appropriate outcome or terminology – particularly with respect to MeHg. Rather, the issue is 

increased risk of an adverse effect.

ATSDR Response: We have changed the wording in Chapter 2, Section 2.3.1.

[Comment continued]

Pg. 34, limitations - It appears that the choice of fish samples was not based on any direct data about 

actual consumption by species. This should be added as a significant limitation of the sampling strategy.

ATSDR Response: We used the direct data collected by Dr. Caro and supplemented these 

data with information gathered from discussions with the residents of Vieques, information 

provided in the Vieques Special Commission Report (Government of Puerto Rico 1999 as 

cited in Navy 2000b), and visits to local fish markets. 

ATSDR agrees that additional information is needed to refine exposure estimates from 

eating reef fish. We know that a significant proportion of Viequenses eat fish regularly. 

However, more information about Viequenses dietary habits would be very useful. It would 

be useful to know the frequency of consumption by gender and age for:

 Reef fish, ocean-going fish, and canned fish,

 Various fish species,

 Portion size, and

 Reef location.

This additional information would allow a more refined risk estimate. In any event, we have 

made changes to Chapter 2.

[Comment continued]

Pg. 49, par. 2 - All biological media are not equally appropriate for all analytes because of a lack of a 

demonstrable exposure-concentration relationship. In general, hair is considered a standard biological 

medium for Hg only. I am not aware of any established method for biomonitoring of Sb in hair. In 

NHANES, CDC quantified Sb in urine.

ATSDR Response: ATSDR agrees. While antimony levels in hair can be measured, 

interpreting the results is difficult. Distinctions are impossible between oral intake of 

antimony (internal exposure) and hair contact with antimony-containing products (external 

exposure). 

[Comment continued]

Par. 2 - “... Dr. Ortiz Roque’s identification of three residents with hair mercury levels above 12 ppm is an 

important finding.” Other than possibly from a clinical standpoint, why is this an important finding? 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-20

Without information on sources of exposure (e.g., canned tuna), no inference for environmental 

exposure can be drawn.

ATSDR Response: We agree. The findings are important from a clinical perspective but do 

not indicate an association to military activities on Vieques. Regarding the finding that some 

women and children with mercury hair levels above a level that might cause harmful effects 

to a developing fetus or a young child indicates excessive mercury exposure for at least 

some residents. While the assumption is that this excessive exposure comes from eating 

fish, only follow up can confirm this. The mercury exposure might have resulted from a high 

frequency of eating a certain fish (e.g., canned tuna, certain reef fish, or certain ocean-going 

fish). The Chapter 2 dose estimates indicate that exposure to mercury can be excessive in 

some people who frequently eat fish that contain moderate to high levels of mercury.

[Comment continued]

Pg. 51, Table 3-2 - The summary information on the studies of mercury in blood is 3-5 years out of date.

ATSDR Response: The studies referred to in Table 3-2 for mercury are the Faroe Islands

study, the Seychelles study, and the New Zealand study. These are the principal studies the 

National Academy of Sciences, the U.S.EPA, and ATSDR use to develop health guidelines. 

The studies have resulted in numerous peer-reviewed journal articles that we consulted 

when evaluating the toxicologic significance of the methylmercury exposure. ATSDR is not 

aware of more recent peer-reviewed studies. 

[Comment continued]

Pg. 52, par. 5 and ff. - “...when... a person is found to have an elevated metal or chemical in a biological 

matrix a follow-up investigation should be considered.”

Why? From an individual chemical standpoint, an elevated biomonitoring result warrants follow-up only 

if there is a potential for adverse effects. From a population-based standpoint, a single elevated level 

provides little or no useful inferential data.

ATSDR Response: ATSDR agrees that a single elevated level in one person provides very 

limited information when it comes to making broad statements about inferring exposure to 

bomb-related chemicals and elements. We have changed the text accordingly. Prudent 

public health practice, however, requires follow-up investigations when persons have 

metals in biological matrices at levels of health concern. A prime example is elevated blood 

lead levels.

[Comment continued]

Pg. 57 - I suggest adding the following to the end of the paragraph: “and whether the results will be 

informative about health risk. It is not, for example, clear that elevated levels of Al or Zn provide useful 

information about health risk.”
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-21

ATSDR Response: We agree and have changed the text.

[Comment continued]

Pg. 69, par. 3 - In this context, “expected” has not been defined. If it is based on NHANES data, it is not 

clear that it is appropriate to assess the distribution of these biomarkers in a Puerto Rico, or Vieques (as 

opposed to U.S.) population based on NHANES data.

ATSDR Response: We reported the findings as stated in a 2006 draft manuscript prepared 

by PRDOH as part of a biomonitoring study in Vieques.. We cannot say what is meant by the

use of “expected.” Given the study context, the PRDOH study could have meant comparison 

to statistics generated by NHANES. We agree with the comment that the U.S. NHANES may 

not be wholly applicable to a Puerto Rican or Viequense population. In Chapter 3 we discuss

the need to include a control or reference population from the Commonwealth of Puerto 

Rico.

[Comment continued]

Pg. 73 - Table 3A-3 appears to be mislabeled based on its identification on pg. 67 where it is described as 

the Phase 2 results (i.e., follow-up on elevated levels in Phase 1), whereas the table, itself, is labeled as 

referring to the Phase 1 results. 

ATSDR Response: We have corrected the numbering of Table 3A-2 (Phase 1 results) and 

Table 3A-3 (Phase 2 results) in Chapter 3, Appendix 3-A.

[Comment continued]

Pg. 76, par. 4 - It is not clear that it is appropriate to combine data from head, pubic and maxillary hair.

ATSDR Response: ATSDR agrees. We have added a caution to Chapter 3, Sections 3.7.2.1 

and 3.7.8.1. 

[Comment continued]

Pg. 77, table - The table does not have a number assigned to it. Also, the data presented for males and 

females separately are not labeled. Are these average levels by sex?

ATSDR Response: The table is labeled Table 3A-5. We have modified the heading to state 

clearly that the values reported are averages for various groups.

[Comment continued]

Pg. 79, par. 1 - Data on matched pair correlations are not presented. In addition, the children’s ages are 

not given. The conclusion about mother-child correlation and in-utero exposure are not substantiated.

ATSDR Response: Dr. Ortiz Roque’s manuscript does not provide data on matched paired 

correlations. As stated in the text, Dr. Ortiz Roque reported that in one subset of 22 

matched pairs, the age of children was less than 5 years. As stated in the text, Dr. Ortiz 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-22

Roque reported that the Pearson’s correlation was 0.93 and the p value was 0.0001. No 

Report changes are warranted.

[Comment continued]

Pg. 84, par. 2 - Where did the 52 subjects reside? What were the criteria for their recruitment? What 

was the dichotomous criterion for dividing the subjects into high and low fish consumption categories?

ATSDR Response: We have modified the text to indicate that the 52 subjects were 

Viequenses. Because this information came from a Webinar, we cannot currently answer 

the other questions. This information is likely to be available when 

Dr. Rodríguez Sierra publishes his data.

[Comment continued]

Pg. 85, table - Given the previous, brief description of the 2009 Rodríguez Sierra study, I would have 

expected to see the data stratified by high and low fish consumption rates.

ATSDR Response: Because this information came from a Webinar, we cannot currently 

answer the question. This information is likely to be available when 

Dr. Rodríguez Sierra publishes his data.

[Comment continued]

Pg. 97, par. 3 - The levels of 85 and 58 μg/L are somewhat misleading. Although 58 μg/L is the lower 95% 

CL on the dose corresponding to a 5% decrease in performance, the value of 5.8 μg/L to a significant 

extent reflects the population variability in the intake dose (μg/kg/day) required to reach 58 μg/L. 

Therefore, the factor of 10 reduction from 58 μg/L is not simply an arbitrary default.

ATSDR Response: The paragraph cited does not discuss 5.8 μg/L or the use of an uncertainty 

factor of 10 to derive 5.8 μg/L from 58 μg/L. The paragraph comes from a CDC Web site and 

is provided for informational purposes. No report changes are warranted.

[Comment continued]

Pg. 102, par. 2 - It is not clear how “cancer registries typically represent the best population-based

dataset for any chronic health condition.”

ATSDR Response: Our intent was to communicate that the infrastructure for reporting 

cancer and the legal requirements for doing so are more rigorous than for most 

noninfectious chronic diseases and typically produce good data. We have clarified the text.

[Comment continued]

Pg. 103, par. 1 - The sentence starting, “One initiative...” is not a complete sentence.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-23

ATSDR Response: We revised the sentence in the fourth paragraph of Chapter 4, Section 4.1 

as listed below. 

The Selected Metropolitan/Micropolitan Area Risk Trends (SMART) project was 

initiated to develop prevalence estimates at the local level.

[Comment continued]

Pg. 108, #2 and ff. Given the latency for most cancers, how do temporal aspects of cancer incidence 

relate to military activities on Vieques?

ATSDR Response The U.S. Navy has occupied some part of Vieques since 1941. Considering 

the latency of most cancers, evaluating cancer incidence and mortality from 1990–2004 is a 

reasonable timeframe. 

[Comment continued]

Pg. 109, #4 - It is important to discuss the socio-economic status (SES) of Vieques relative to Puerto Rico.

ATSDR Response: ATSDR added a discussion of SES in Chapter 1.

[Comment continued]

Pg. 115, first bullet - Where are the locations of the reference populations given here? It would be useful 

to have a map at this point.

ATSDR Response: We agree a map would be helpful. Unfortunately, Figure 2 of Massol-Deya 

2000 contains only the study areas. Other than the name, no details of the reference area 

and sampling locations are available. 

[Comment continued]

Pg. 116, first complete bullet - Do the “toxic” levels of “all metals” referred to here refer to plant 

toxicities or human toxicities? Also, why are “absorption rates” for Pb and Cd referenced here instead of 

concentrations?

ATSDR Response: We have modified the text in Chapter 5, Section 5.2.1 of the Report to 

address these comments.

[Comment continued]

Last bullet. Are the goats in Puerto Rico that are being compared to those in Vieques the same species of 

goat? Are they the same age? What were the levels in Vieques and Puerto Rico goats? Was the 

difference statistically significant?

ATSDR Response: This information was not included in the publication (Massol-Deya 2002) 

that presented the hair sampling data. Among other things, the lack of this information 

precluded ATSDR from using these data to evaluate human exposure from consuming locallivestock meat and milk products.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-24

[Comment continued]

Pg. 121, Table 5-1 - If the childhood exposure duration (ED) is assumed to be 6 yr, the adult ED should be 

70 - 6 = 64 yr rather than the 70 yr value used here for adults if a 70 yr lifetime is assumed. Also, why do 

the ingestion rate (IR) assumptions differ for the MRL calculation (0.10, 0.05 kg/day) versus the 

NOAEL/LOAEL calculations (0.05, 0.01 mg/kg/day)?

ATSDR Response: Table 5-1 has been modified to show that exposure duration had no 

effect on the estimated daily dose. The ingestion rates used for comparison to the MRL of 

0.10 and 0.05 kg/day reflect 95th percentile intake rates for adults and children, respectively. 

The rates for the NOAEL and LOAEL comparisons reflect 95th and 50th percentile intakes for 

children only. 

[Comment continued]

Pg. 124, par. 2 - How many pineapple samples were taken? Was it only 1? If so, how can this observation 

be used to support modeling?

ATSDR Response: Lopez Morales (2005) does not overtly state the sample number, but 

apparently a total of 72 samples were taken: 36 from the study site and 36 from a reference 

plantation. 

[Comment continued]

Pg. 126, par. 2. I do not see that these very limited data support any larger assessment of exposure or 

risk.

ATSDR Response: Thank you for your comment. ATSDR agrees that limitations in the current 

sampling data make it difficult to evaluate the extent of public health impact from exposure 

to metals in locally grown produce. Given the uncertainties in the data, ATSDR believes 

prudent public health practice requires further investigation of this potential exposure 

pathway. To address this data deficiency, ATSDR has recommended further sampling. 

[Comment continued]

Pg. 164, par. 1. The sentence starting, “Examining results from background locations not directly 

affected by military operations...” does not make logical sense. If the samples are, in fact, background 

samples, this implies that they are assumed not to be impacted by specific activities.

ATSDR Response: In Chapter 7, Section 7.2.4, we inserted parentheses around the phrase to 

indicate that background locations are by definition not affected by military operations.

[Comment continued]

Pg. 165, par. 2 - This is a reasonable assumption for the sites of the actual explosions. However, when 

considering off-site transport, surficial material becomes more important.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-25

ATSDR Response: Most of the surface soil samples used in this evaluation were collected 

directly from the LIA. We recommend that any future sampling conducted outside the LIA 

consider surficial (top 3 inches) contamination.

[Comment continued]

Pg. 190, 1b - Hair is not an appropriate medium for biological monitoring for most contaminants. Blood 

is generally more appropriate. But for blood too, the determination of the applicability of its use for 

biological monitoring is contaminant-specific.

ATSDR Response: We agree that with the exception of mercury, hair is of limited use for 

environmental exposure monitoring. Numerous statements in the Report convey this 

message. We also agree that if other metals are considered as part of a biomonitoring study, 

developing a scientifically rigorous and valid protocol is important. This includes determining 

whether the results will inform about health risk. 

[Comment continued]

Pg. 192, #2 - The review has not provided any basis to conclude what this single observation of Cd levels 

in the pigeon peas implies for exposure. This observation should not be presented and discussed 

without proper context.

ATSDR Response: Text in Chapter 5, Section 5.2.2 of the Report has been modified to 

address these comments.

[Comment continued]

Pg. 193, #5 - Add “and false low values” after, “To avoid false high values”

ATSDR Response: Text in Chapter 5, Section 5.3 of the Report has been modified.

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-27

Reviewer 2

Overall, has ATSDR’s re-evaluation of public health issues associated with historical 

bombing exercises at Vieques been appropriate?

[Comment] The ASTDR document: A Fresh Look at Environmental, Biological, and Health Data from the 

Island of Vieques, attempts to explain in readily accessible language, the potential for human health 

effects as a result of decades of use of portions of the island as a U.S. Navy training and testing area. The 

document has been developed using data collected by related agencies specifically for the purposes of 

this risk assessment as well as data collected by external sources. The risk assessment discussion has 

been organized based on individual pathways as a means to both structure the information and explain 

the potential risks in a systemized manner. 

In evaluating this document, I’ve approached the information as a scientist versed in bioavailability of 

contaminants in soil systems as well as someone familiar with Vieques. Before graduate school, I worked 

in Vieques for two winters during the mid-1980s. At this time the Navy still had an active presence on 

the island. I remember being able to both feel and hear some of the munitions testing during my time 

on the Island. I read about protests by Viequenses that were a factor in the decision to end the testing 

operations. I have also been back since the Navy ceased operations and the former Navy bases became 

wildlife areas managed by U.S. Fish and Wildlife. 

Understandably, the residents of Vieques are concerned about potential negative health effects as a 

result of the decades long use of the island as a training and testing area for the Navy. Certain factors, 

including high cancer rates and increased incidences of select medical conditions would suggest to 

concerned residents that there is likely a link between the testing operations and these observed health 

effects. The risk assessment document attempts to ascertain any potential relationship between the 

testing and these observed effects by going through each exposure pathway and discussing all available 

evidence linking any human health effects to the testing results for each pathway. 

This effort is handicapped by a number of factors. The testing began several decades before any 

research efforts to document health effects were started. It is likely that the records of testing re: 

chemical composition, quantity and final fate of the ordinance used, is not complete. Some of the data 

used for the current effort was compiled by external scientists, without the appropriate quality 

assurance, quality control, information on methods, and control populations that are general considered 

essential for the data to be considered appropriate for use. Finally, the necessary studies to provide 

quantitative guidance on contaminant concentrations in different human tissues, soils, fish that are 

likely associated with health effects are not available for all of the contaminants considered in this 

document. 

In general, this review is very sympathetic to the concerns of the residents of Vieques. Data is included 

in this analysis that is likely inappropriate for use in a more rigorous exercise. Examples of this include 

web casts and unpublished data on health of residents. The desire to address concerns of residents has 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-28

also resulted in credence and attention being given to certain pathways that are not realistically 

supported by the data as being a significant threat.

ATSDR Response: Thank you for your summary comments.

Has ATSDR adequately addressed the pathways of human exposure to bombing rangespecific contaminants?

[Comment]

The document divides the potential for harm to have resulted from Navy activities into the following 

categories:

Consumption of fish

Terrestrial food chain pathway

Air pathway

Soil pathway

Drinking water pathway

The pathway approach is appropriate. In addition, all relevant pathways have been considered.

ATSDR Response: Thank you for your comments.

Please include specific comments on:

Consumption of seafood from reefs near Vieques

Use of biomonitoring tools to assess exposure to metals and other hazardous chemicals in 

blood, urine, or hair that are related to historical bombing exercises

[Comments combined by reviewer]

The primary conclusions of the report are that the pathways that have the potential to be of concern are 

the consumption of fish and the terrestrial food chain pathway. Mercury is the primary contaminant of 

concern for the consumption of fish and Cd is the primary concern for the terrestrial food chain 

pathway. The authors cite data from a number of studies that show elevated Hg concentrations in 

certain fish species caught in the vicinity of testing impacted reefs in Vieques. They also cite less credible 

studies that indicate elevated Hg concentrations in hair for, depending on the study, a significant 

number of Viequenses in comparison to control populations (Dr. Colón de Jorge and Dr. Rodríguez

Sierra). The elevated Hg in humans is related to the observed high Hg content in fish. The authors of the 

current report conclude that reducing fish consumption and avoiding certain species of fish are sensible 

options to reduce any risk associated with elevated Hg in seafood. These conclusions are reasonable 

based on the Hg concentrations in certain of the fish species sampled as well as the availability of other 

fish species that have been shown to have low levels of Hg in edible tissue. The authors of this report 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-29

present the findings of Dr. Colón de Jorge and Dr. Rodríguez Sierra while also pointing out the flaws or 

unknowns for both studies. It does not make sense to spend additional resources to test human Hg body 

burdens when a clear option for reducing Hg in diets while maintaining fish as a staple source of protein 

has been described. The one factor that is not considered in this discussion is the potential for the 

observed excess Hg in fish to be related to Naval activities. There is no discussion in the document on 

the quantities of Hg that were likely used in Naval activities or whether elevated Hg concentrations have 

been detected in reefs impacted by Naval activities. So while the conclusions and recommendations of 

the ASTDR report re fish consumption are reasonable, a clear link has not been made between the 

observed elevated concentrations in certain fish species and Navy activities on the island. 

ATSDR Response: The Report focused heavily on mercury in fish because it poses the 

greatest risk of those scenarios assessed. Chemical results for soil, air, water, and biota do 

not reveal extensive contamination and do not identify an association between mercury and 

the bombing activities. We clarified this point by revising the Executive Summary and 

Chapters 1, 2, 3, 6, and 9.

Consumption of food (produce, meat, dairy, eggs) grown on the island

Exposure to air, soil, and water on Vieques

[Comments combined by reviewer] The other main concern outlined in the report is the potential for 

high Cd consumption from eating pigeon peas. This recommendation is based on a single study that 

included samples of about 20 pigeon pea plants from a single area on the island. This recommendation 

is also based on the assumption that a high quantity of pigeon peas will be part of a daily diet and that 

these peas will be grown on the island. For this reviewer, this conclusion and recommendation is not 

supported by the available data. There are a number of reasons for this. 

The report concludes that there is no basis for concerns re direct ingestion of soils (the soil pathway) or 

from airborne contaminants. Both the available data and modeling efforts show no evidence of or 

potential for significant hazards associated with either the soil pathway or the air pathway for residents 

in the middle portion of the island. This is the inhabited portion and has always been exempt from 

military testing. For pigeon peas to have excess Cd as a result of the Naval testing, there would also need 

to be associated soil contamination. As modeling and data show no hazard from the soil pathway or the 

airborne pathway, it is also highly unlikely that soils would have become sufficiently contaminated with 

Cd as a result of the Naval activities to result in consistently elevated plant Cd concentrations in the 

edible portions of plant tissue. 

As was stated earlier with Hg, there is no evidence provided of high Cd use or Cd concentrations in any 

of the munitions used in the testing. Cadmium was historically used as a pigment. It is not clear that any 

more than trace amounts of this metal were involved in any of the Naval activities. Soils can be naturally 

elevated in Cd- for examples soils in Salinas, California, derived from Monterrey shale have Cd 

concentrations ranging from 0.05-10.1 mg kg-1(Burau et al., 1973). Sediment samples collected from the 

LIA show Cd concentrations ranging from 60-110 mg kg-1. This was in an area where metal 

concentrations were elevated through the sampling depth as a result of direct impact of explosives. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-30

While these sediment Cd concentrations are clearly very high, they are directly in the impacted area. It is 

highly unlikely that agricultural soils will show any detectible increase in soil Cd as a result of the Navy 

activities. 

There are other factors that make the high Cd concentrations in this single study an insufficient basis for 

concern. Plant uptake of Cd will likely vary based on specific soil and plant factors. The study used as a 

basis for concern was from a single site. It is highly likely that Cd concentrations for peas grown in 

different areas of the island would vary significantly. A mean value, from a range of sites, showing highly 

elevated Cd, would be much more significant. 

Bioavailability of Cd will also vary based on the nutritional status of the individuals. A study showed 

significantly higher adsorption of Cd in cases where Ca and Fe were below required levels (Reeves and 

Chaney, 2001). Sufficient Zn in diets was also observed to protect against excess Cd adsorption. The 

most studied cases of adverse health effects as a result of excess diet Cd were in Japan where milled rice 

was the staple grain. This occurred after WW II when diets were poor in Japan. Pigeon peas are likely a 

far superior source of essential elements than milled rice. In addition, diets in Vieques are likely superior 

to those where Cd in food resulted in adverse health effects.

Finally, it is highly unlikely that enough pigeon peas are grown in Vieques to feed a significant portion of 

the population for any amount of time. Although historically sugar cane was an important crop 

economically, agriculture in Vieques is limited. Families will have a few citrus trees, some banana and 

other sundry plants, however, there are very few large- scale farms in Vieques. During my time there, 

there was one attempt to grow tomatoes for export that failed. There isn’t sufficient rainfall to 

consistently grow crops commercially without irrigation. 

The above comments can be applied to the entire food chain transfer model (excluding seafood). 

Looking at the soil pathway section, there is no data presented in this chapter. However, based on the 

airborne discussion and the conclusions in the soil chapter, it seems pertinent to revisit the conclusions 

reached on metal uptake from home grown vegetables. That chapter did not include data on metal 

concentrations in soils where plants were grown. The chapter on soil pathways suggest that the 

potential for elevated soil metals as a result of Navy activities in the populated portion of the island, the 

portion that might be used for agricultural activities, is minimal. Airborne spread of metals would be the 

primary pathway for metal contamination of these soils. Metals would persist in the soil over time, 

unlike the organic contaminants that were also measured. The absence of any increase in soil metals 

suggests that the elevated Cd content in the pigeon peas is not likely related to soil contamination as a 

result of previous Naval activities. There are many factors that can lead to elevated plant metal 

concentrations, including a high soil electrical conductivity level, low soil Zn concentrations, and there 

may be a relation with low soil phosphorus. Many of these soil factors can be controlled with proper 

management. Appropriate soil testing and agricultural practices are suggested as a means to address 

concerns. 

ATSDR Response: Thank you for your comments. Relevant text in Chapter 5, Section 5.2.2 

has been modified. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-31

Does the Vieques summary report adequately present and describe the limitations and 

uncertainty of assessing human exposure to bombing range-specific contaminants?

[Comment] Yes

Are independent studies utilized appropriately in the determination of potential health 

hazards?

[Comment] In the interest of including as much information as possible with a particular goal of 

including any information generated by researchers from Puerto Rico, information is included in this 

report that would not be considered of sufficient scientific integrity to be included in most studies. 

There are a range of reasons for doing this, and the inclusion of these studies has not resulted in 

unreasonable recommendations. The recommendations from the report are likely to be more broadly 

accepted because this data has been included. 

ATSDR Response: Thank you for your comment

On the basis of ATSDR’s re-evaluation of historical bombing activities in the Vieques 

summary report, has ATSDR reached the appropriate conclusions and recommendations?

[Comment] See discussion on plant Cd concentrations above, however general response is yes.

ATSDR Response: None required. 

Select the appropriate category below:

List recommended changes or reasons for not recommending

o Recommend (X)

o Recommend with Required Changes ( )

o Not Recommended ( )

Additional Questions:

Are there any comments on ATSDR's peer review process?

[Comment] No

Are there any other comments?

[Comment] In general, the report is potentially too lenient in its use of any and all appropriate data. The 

report expresses concerns with minimal basis. The information presented suggests that the history of 

naval activities on Vieques has not resulted in any measurable human health impacts. With that said, it 

is likely that if full and unrestricted access was granted to the former naval areas including home 

construction, the conclusions of this risk assessment would need to be revisited. The area is likely to 

require extensive remediation before unrestricted access can be permitted. In addition, the limited data 

presented in this report on contamination both in the waters around Vieques and for portions of the 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-32

impacted areas suggest that a full ecosystem risk assessment would reach very different conclusions 

than this limited human health risk assessment. 

ATSDR Response: Thank you for your comment. We changed the text (in the Executive 

Summary, Chapters 1, 2, and 3 to improve the discussion of contaminants in bombs and 

their possible contribution to various pathways. Iron, aluminum, copper, manganese, zinc, 

and lead are the metals most likely to be elevated in LIA soils from bombing activity, though 

other metals were also found in the bombs. It should be noted that all of these metals are 

also naturally present in the soils and rocks of Vieques (ATSDR 2003a, Learned 1973, USGS 

1997 and 2001).

Although associations with these samples and military activities are not strong, the samples 

were not designed for a thorough ecological assessment. Thus they should only serve as 

indicators of further study.

Also, in Chapters 7 and 9 we clarified that ATSDR recommends environmental assessment 

and remediation activities continue at the LIA and at other potentially contaminated sites on 

Vieques. Restricted access to those areas should continue until the areas are cleared for 

unrestricted access.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-33

Reviewer 3 

Overall, has ATSDR’s re-evaluation of public health issues associated with historical 

bombing exercises at Vieques been appropriate?

[Comment] Yes, the re-evaluation has been appropriate. The exposure pathways have been adequately 

considered, local studies that were made available were included and analyzed and proposals have been 

made for further work. My answer is qualified by only two things. First, there seems to be a degree of 

ignorance on local conditions, which are reflected in the report: the recommendation for Viequenses to 

follow the U.S.EPA/FDA’s national fish advisory and its three recommendations for selecting and eating 

fish and shellfish, and the lack of knowledge concerning the public water supply of Vieques. My second 

qualification has to do with the multiplicity of samplings and data gathering activities that are 

recommended to fill current data gaps. Considered individually, I generally agree with them. However, 

taken as a whole, they constitute a huge and expensive undertaking likely to take many years. It is 

suggested that priorities be established and the most important gaps be filled first in order to establish 

within a reasonable period of time whether the health of Viequenses is at risk or not.

Details of this are given below.

ATSDR Response: Thank you for your comments. We have modified the text in Chapter 2 to 

better reflect local fish consumption habits. We also modified Chapter 8 to address concerns 

about the public water supply. ATSDR considers education about choosing fish with lower 

mercury levels to be the highest priority public health recommendation and plans to work 

with our partners and the community to prioritize other recommendations.

Has ATSDR adequately addressed the pathways of human exposure to bombing rangespecific contaminants?

[No Comment]

Please include specific comments on:

Consumption of seafood from reefs near Vieques

[Comment]

1. I agree with recommendations #1-3. However, ATSDR should reconsider recommendation #4 

(Viequenses follow the U.S.EPA/FDA’s national fish advisory and its three recommendations for 

selecting and eating fish and shellfish). These recommendations are hardly applicable at 

Vieques. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-34

Consider that Viequenses eat fish provided by local fishers, which consist mainly of those shown in Table 

2-1. The EPA/FDA’s recommendations are for them to eat canned light tuna, or three other species 

(salmon, pollock and catfish) that are non-existent in the area. This is not going to happen, and instead 

the recommendation should be to eat local species that are low in mercury, and a table should be 

provided.

Viequenses are asked to check local advisories about fish safety. To my knowledge no such advisories 

are made in Puerto Rico. This same recommendation makes reference to “local lakes, rivers...” of which 

there are none in Vieques. Using these references gives the impression that ATSDR is not aware of the 

local situation.

Viequenses are told not to eat shark, swordfish, king mackerel, or tilefish, species that are not listed in 

Table 2-1. 

ATSDR Response: We agree that portions of the EPA/FDA national fish advisory do not apply 

to Viequenses. We have modified this recommendation in Chapter 2,Section 2.3.2. 

Using all the data from Dr. Caro’s survey, we expanded the list of fish that Viequenses eat 

(see Table 2-1 in Chapter 2, Section 2.2.1). Table 2-1 now shows the 22 fish species and two 

shellfish (i.e., conch and lobster) that the 51 respondents reported to Dr. Caro that they eat. 

Note that residents reported eating shark, tuna, and marlin—species that can have very high 

mercury levels. In addition, residents reported eating salmon, a low-mercury containing 

species. That Viequenses eat canned tuna seems a reasonable assumption. Therefore, some 

portions of the EPA/FDA national advisory apply while other portions clearly do not. 

During the November 2009 scientific meetings, a scientist also criticized the agency for 1) 

not citing the EPA/FDA national fish advisory and 2) contradicting the national advisory in 

ATSDR’s previous, 2003 Fish PHA findings. That Viequenses know which reef fish have higher 

mercury levels is important, as is knowing which reef fish have lower mercury levels. ATSDR 

now recommends that the agency develop a health education program specific to Vieques. 

This health education program should empower Vieques residents to choose to eat fish that 

are lower in mercury.

[Comment]

2. Dr. Caro’s study:

Table 2-2 appears to be incomplete (it only shows three fish species). Caro characterizes this 

three fish as “...an example, the average contents of the metal may be mentioned in the 

following fish....” She adds that: “Additional data in Annex 10 illustrate these results.” However, 

this and many other annexes were not included in the copy of the Caro report that was sent by 

ATSDR. 

ATSDR Response: We added the additional information from Annex 10 to Table 2-2 in 

Chapter 2, Section 2.2.1. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-35

[Comment]

I agree that not knowing whether the results are dry weight or wet weight prevents comparison with 

other datasets and estimation of human doses from eating fish, but assuming dry weight would provide 

a conservative estimate and allow for qualified comparisons and estimation of doses. If wet weight is 

used the actual tissue concentrations could be higher.

ATSDR Response: We provided additional analysis of Caro’s data. See Chapter 2, Section 

2.2.1

[Comment]

The correct spelling for Parquera is Parguera. The Caro report appears to make the same mistake.

ATSDR Response: The spelling of this town is corrected. 

[Comment]

It is said the ATSDR is currently renewing its efforts to determine whether the data was dry weight or 

wet weight. Please note that Dr. Caro passed away in 2002.

ATSDR Response: We tried to contact the laboratory. We revised the sentences in the 

Chapter 2, Section 2.2.1 to reflect our efforts accurately. 

[Comment]

3. Fish and Seafood Data from ATSDR

It is indicated that ATSDR used standard body weights for adults and children. If this refers to a 

mainland standard, it should be noted that generally Puertoricans are smaller in size and weight, 

which could under estimate calculations on tissue concentration.

ATSDR Response: In ATSDR’s 2003 Fish PHA, we used standard body weights of 70 kg for 

adults and 16 kg children. The point that Puerto Ricans typically weigh less also was raised 

by scientists in our November 2009 discussions. Therefore, in the current Report, we used a 

range of body weight from 4.5 to 100 kg (9.9 to 220 pounds) to represent the body weight 

of various age groups (see Chapter 2, Section 2.6, Table 2A-1 in Appendix 2A-2). We also 

included a range of daily fish ingestion rates to cover daily intakes up to the 99th percentile. 

Therefore, the estimated doses of mercury in this report include a much wider range of 

doses than the 2003 Fish PHA.

[Comment]

4. There is a poster presentation titled “Health Risk Assessment of Arsenic from Fish in Coastal 

Waters of Vieques, PR” by Acevedo et al, which measured arsenic concentrations in eight edible 

fish in Vieques in 2001. Concentrations ranged from 0.3 to 3.53 mg/Kg wet. The study 

considered different exposure scenarios for inorganic As and found that concentrations 

exceeded EPA’s reference dose of 0.0003 mg/Kg/d in six or more fish species for systemic 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-36

effects in adults and children. The probability of excess lifetime cancer for exposure to As by 

adults was estimated to exceed the acceptable cancer risk of 10-6. I do not believe that this study 

has been published but the poster may be obtained from Dr. Carlos Rodríguez Sierra at the 

School of Public Health of the Medical Sciences Campus of the University of Puerto Rico.

ATSDR Response: ATSDR has attempted to locate this information but has not been 

successful. Average total arsenic in fish samples collected by ATSDR in 2001 ranged from 

1.85 ppm (or mg/kg) to 2.84 ppm (wet weight), with one trunkfish sample showing 8.3 ppm 

total arsenic. The median total arsenic concentration in fish was 2.8 ppm. Conch and land 

crabs had similar levels (0.3 ppm and 3.9 ppm, respectively). These levels are typical for total 

arsenic concentrations in seafood, and in particular for fish (WHO 2001, Rodríguez Sierra 

2002, ATSDR 2007) and are similar to the levels reported by the reviewer in the poster (0.3-

3.53 ppm). 

Numerous studies have shown that the predominant form of arsenic in fish is 

arsenobetaine, an organic arsenic (ATSDR 2007). Arsenobetaine is not harmful to humans 

because humans rapidly excrete this chemical unchanged within 24 to 48 hours of ingestion. 

The remaining small amount of inorganic arsenic in fish is not harmful (WHO 2001). 

Spiny lobster from Vieques reef were shown to have total arsenic levels ranging from 27 

ppm to 48 ppm with an average of 33 ppm. Like fish, most of the arsenic in spiny lobster 

(genus Panulirus) is arsenobetaine and only about 0.05% is inorganic arsenic (Peshut et al. 

2007). No changes were made in the report.

Use of biomonitoring tools to assess exposure to metals and other hazardous chemicals in 

blood, urine, or hair that are related to historical bombing exercises

[Comment]

1. The chapter provides a good review of six Vieques human biomonitoring studies. I was surprised 

to learn that ATSDR’s previous public health assessments did not review biomonitoring data 

from Vieques. 

ATSDR Response: Thank you for your comment. The biomonitoring studies were not readily 

available when the public health assessments for Vieques were being written or, in the case 

of the PRDOH study, had not yet been conducted. When ATSDR began its evaluation of

Vieques in 2009, we knew that PRDOH had conducted a study, but were not aware that a 

draft manuscript was available. ATSDR was provided a draft copy of the PRDOH study in late 

2009

[Comment]

2. The Puerto Rico Department of Health (PRDOH) appears to have conducted the most 

comprehensive biomonitoring study, in which it collected hair, urine or blood samples from 500 

randomly selected Viequenses. However, no public report was ever released and it was not until 

August 2009 that ATSDR obtained a draft, unpublished manuscript. Quite frankly, the way this is 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-37

written makes one wonder why it took three years for ATSDR to obtain a copy, and how it was 

obtained. 

ATSDR Response: When ATSDR began its evaluation of Vieques in 2009, we learned that 

PRDOH had conducted a study, but were not aware that a draft report was available. Shortly 

before the November 2009 meeting with invited scientists, ATSDR received a draft copy of 

the PRDOH study.

[Comment]

3. The discussion in Chapter 3.3 of the strengths and limitations of previous human biomonitoring 

studies for Vieques is comprehensive and balanced. It is recognized that NHANES biomonitoring 

data applies to the entire U.S. population and that due to regional, cultural, and ethnic 

differences they can only cautiously apply to Puerto Rico. I completely agree that when looking 

for a Vieques comparison group, a control population from another town in Puerto Rico should 

be more appropriate.

ATSDR Response: Thank you for your comment.

[Comment]

4. The conclusions from Dr. Colón de Jorge’s investigations indicate that children could not be 

exposed to metals in paint as adults might be. As EPA states in 

http://www.epa.gov/lead/pubs/leadinfo.htm#hazard (accessed 19July10):

“Lead-based paint may also be a hazard when found on surfaces that children can 

chew or that get a lot of wear-and-tear. These areas include

Windows and window sills.

Doors and door frames.

Stairs, railings, and banisters.

Porches and fences.”

My own experience with lead paint studies indicates that Puerto Ricans tend to paint their houses using 

layer upon layer of paint, and that the inner layers (which are the older) are the ones that have lead 

paint. Children will chew all the layers, thus exposing them to the lead paint.

ATSDR Response: We agree that children can be exposed to lead from lead-based paint and 

have added a comment to Chapter 3, Section 3.7.9.1. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-38

[Comment]

5. “Dr. Colón de Jorge pointed out that antimony levels were high because antimony was used in 

explosive ordnance on Vieques, thus making the case that military exercises was the reason 

antimony levels were high.” This conclusion appears to have no supporting data or analysis and 

the review by ATSDR of the report should so state.

ATSDR Response: Dr. Colón de Jorge states that antimony levels in bombs were high and 

this is the reason that some children have high antimony levels. We have modified the text 

in Chapter 3, Sections 3.2 and 3.7.9.1 to include Dr. Colón de Jorge justification. We also 

have pointed out that Dr. Colón de Jorge did not describe how residents might have been 

exposed to antimony. 

[Comment]

6. The discussion of the investigations by Dr. Carlos Rodríguez (this is the same person as the one 

referenced in comment 4 of the section on consumption of seafood from reefs near Vieques 

above) is based on a presentation made in a webinar. Although it is stated that Dr. Rodríguez 

intends at some point to publish his data, he has apparently not done so, which raises an overall 

concern that I have about the lack of peer review of many of the local studies that are presented 

in the ATSDR report. 

ATSDR Response: ATSDR agrees that using peer-reviewed data is preferable. But data 

collected and analyzed using valid quality assurance/quality control procedures is also 

acceptable. In an effort to consider all available Vieques data, ATSDR chose to include the 

non peer-reviewed data in the Report. In the Report appendix, ATSDR summarizes all the 

available data and designates whether the data are peer-reviewed. In e-mail conversations 

with Dr. Rodríguez Sierra, he stated that his biomonitoring data were submitted for 

publication and are currently in the journal’s peer-review process. Those data will be 

available to ATSDR after publication

Consumption of food (produce, meat, dairy, eggs) grown on the island

[Comment]

1. This chapter includes an analysis of several studies dealing with contaminants detected in locally 

raised garden produce and livestock. All the studies present serious limitations. For example, 

one included plant stems and leaves but did not include the edible portions of the plants 

sampled. It appears that the locally grown pigeon peas could have a high cadmium level, but, 

again, there are insufficient data.

ATSDR Response: ATSDR concurs. Thank you for your comment.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-39

[Comment]

2. Reference is made to USDA’s suggestion of several simple methods for reducing metal uptake 

when soils are contaminated. It is stated that most home gardeners use many of the suggested 

practices. However, the referenced website goes to a very general page on plants and crops. A 

more specific reference should be provided, insuring that the suggested practices are applicable 

to Vieques. 

ATSDR Response: No specific reference was available. We defaulted to USDA 

recommendations, which are generally applicable and relevant to gardening and agriculture.

Exposure to air, soil, and water on Vieques

[Comment]

1. Air Pathway The chapter makes no mention of the possibility of Saharan dust contributing 

contaminants to the air or soil in Vieques. For example, see Garrison et al (Rev. Biol. Trop. 54 

(Suppl. 3): 9-21. Epub 2007 Jan. 15.) who sampled in the Virgin Islands where trace metal 

concentrations in the Saharan dust were found to be similar to crustal composition. Although I 

think that metals concentrations in Saharan dust are not going to be high enough to make a 

significant contribution to metals found in Vieques, the issue should be addressed.

ATSDR Response: African Dust Storms: The 2003 Air PHA evaluated the public health 

implications of exposure to airborne particulates from African Dust Storms (pages 59–61) 

and found that PM10 (and PM2.5) from such storms on Vieques were not at levels of health 

concern. However, no contaminant specific data on dust from African Dust Storms were 

available at the time of the Air PHA (which recommended further evaluation if such 

contaminant specific data became available). Contaminant specific dust data are presented 

in a recent study by Gioda et.al. (2007) and a discussion of this information has been added 

to Chapter 6, Section 6.2.3.

[Comment]

2. The discussion of post-Air PHA sampling results and modeling studies as well as recent BIP 

detonations is comprehensive and leads to the stated conclusion that in the residential areas of 

Vieques, airborne contaminants from past military operations at the Vieques Naval Training 

Range would have been essentially nondetectable and unlikely to have resulted in harmful 

effects. 

ATSDR Response: Thank you for your comment. 

[Comment]

1. Soil Pathway This chapter evaluated potential direct soil exposures in two situations: people 

who stayed on the LIA property during 1999-2000 protests and people who live in the island’s 

residential areas. It concluded that people who lived on the LIA during protests were not 

exposed to soil contaminants at levels high enough to cause adverse health effects. This 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-40

conclusion is well supported by the available data as discussed in the report. Concerning the 

island’s residential areas, no soil data are deemed adequate to characterize potential exposures 

fully. Although current or reasonable recent data supports the conclusion that the existing 

contaminant levels at residential areas are not likely to cause adverse effects, there is a lack of 

historical data that would support a wider conclusion to the effect that it never has. The report 

calls for additional sampling to resolve existing uncertainties, which would be appropriate, but 

the wider question is now impossible to resolve. 

ATSDR Response: Thank you for your comment. 

[Comment]

Drinking Water Pathway 

1. The Puerto Rico Aqueduct and Sewers Authority (PRASA), a public corporation in existence since 

1945, is charged with providing drinking water and wastewater treatment for the 

Commonwealth of Puerto Rico. It is the only entity in the United States with a statewide 

mandate, and as such is one of the largest water and wastewater utilities in the United States. In 

2005 PRASA ran 130 different water systems throughout Puerto Rico, which processed 500 

million gallons of water a day. It also operated 29 sewage disposal plants and 1,600 pump 

stations. Vieques is part of its service area. While it is correct that in recent years (for about 

eight years until 2004) PRASA had part of its operations partially conducted by private 

corporations such as the mentioned Compañía de Aguas or at another time by ONDEO de PR, it 

has always been regulated by the Safe Drinking Water Act as a public water system. This 

regulatory function has been delegated by EPA to the Puerto Rico Department of Health (DOH). 

PRASA is required to annually produce and distribute to its users Consumer Confidence Reports 

where the quality of its water is reported and explained in non-technical language. Such reports 

for the years 2004-2009 can be obtained at 

http://www.acueductospr.com/AMBIENTE/ccr_reports.htm

(the system that feeds the Vieques pipeline appears under 5386-Humacao Urbano and then as Río 

Blanco in the pdf file) and reports for earlier years should easily be available at PRASA or the DOH. 

This data should be enough to settle the question concerning the quality of the pipeline water. For 

example, the data for 2009 shows that the lead action level of 15 ppb was exceeded four times. 

ATSDR Response: We have modified text in Chapter 8, Section 8.1 to correct any inaccuracy 

regarding the current operators of the public water supply. We did not include detailed 

descriptions of the water supply system; it could detract from our evaluation of possible 

exposures from all water supplies, past and present.

The water quality reports from 2004–2009 referenced in the comment indicate that the 

pipeline supply has occasionally exceeded drinking water standards for microbial 

contaminants, turbidity, and lead. Elevated lead levels, detected particularly in 2006 and 

2007, were not related to military exercises on Vieques. But regardless of source, lead in 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-41

drinking water is an important public health issue. ATSDR has reworded text and added 

discussion to address these points in Chapter 8 and Chapter 9, Sections 9.8.1, and 9.8.2 of 

the Report.

[Comment]

2. The ATSDR report also addresses wells that had been and are now occasionally used for drinking 

water. These wells are very likely to belong to PRASA, who should have historical data on the 

quality of their water. Also concerning the wells, the presence or absence of a sanitary landfill in 

Vieques that might be impacting groundwater and the use of septic tanks for sewage disposal 

should be discussed.

ATSDR Response: We added discussion about historical data to the Report in Chapter 8, 

Sections 8.2.2, 8.2.4.2, and 8.3.1.2. We did not attempt to gather additional historical 

information on the water quality of these wells. Even if available, questions about sampling, 

analytical, and quality control procedures from the 1970s and 1980s render unlikely the 

possibility that such reports would give us sufficient information to alter our current 

conclusions. Similarly, a lack of adequate historical data precludes any conclusion about 

more remote (1970s and 1980s) public supply well exposures. 

Thus, in Chapter 8, Section 8.3.1.2 we reworded text and added a statement about possible 

nonmilitary sources of contaminants, including sanitary landfills and septic systems. While 

sanitary landfills and septic systems could affect groundwater resources, whether they have 

was not a focus of our evaluation. Instead, ATSDR based its conclusions on actual sampling 

of supply wells, private wells, and taps.

[Comment]

Although it would be good to have data on the rainwater systems, their overall use and effect is likely to 

be very small.

ATSDR Response: Thank you for the comment.

[Comment]

ATSDR should consider rewriting this whole chapter to better reflect the role of PRASA in supplying the 

drinking water at Vieques.

ATSDR Response: We have modified text in Chapter 8, Section 8.1 to correct any inaccuracy 

regarding the current operators of the public water supply. We did not include detailed 

descriptions of the water supply system. We were concerned that it might detract from our 

evaluation of possible exposures from all water supplies, past and present.

Does the Vieques summary report adequately present and describe the limitations and 

uncertainty of assessing human exposure to bombing range-specific contaminants?

[Comment]
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-42

I believe that the report is not as clear as it should be, particularly from the point of view of a lay person. 

The limitations and uncertainty are adequately presented, for a person that carefully reads the report in 

its entirety. Just reading the summary report does not present the same picture.

ATSDR Response: In the Report, we provided additional information regarding 

environmental data available for assessing any exposures associated with the military 

exercises on Vieques. We identified that those chemicals found in environmental samples 

were also found in explosive ordnance. Changes were made to the Report’s Executive 

Summary and Chapters 1, 2, 3, 6, and 9.

Are independent studies utilized appropriately in the determination of potential health 

hazards?

[Comment]

Yes, but they are being given the same weight as other peer-reviewed studies.

ATSDR Response: The principal consideration for independent studies is the importance of 

describing all the environmental and health data available for Vieques—even when some of 

the data were not peer reviewed. We considered hair data results for numerous metals. 

Some scientists believed these data were valid and drew conclusions from them. ATSDR 

described the limitations of these data in detail, pointing out the inability to distinguish 

between external contact and internal ingestion for most metals, except mercury. To this 

extent, ATSDR attempted to report fairly the available data and to provide insight into their 

value for health decisions. In our conclusions and recommendations, these data of 

questionable quality either were not used (e.g., metals in hair, except mercury) or were 

used qualitatively (e.g., arsenic in urine reported in a Webinar).

On the basis of ATSDR’s re-evaluation of historical bombing activities in the Vieques 

summary report, has ATSDR reached the appropriate conclusions and recommendations?

[Comments]

Yes as to their quality, but I have the following comments regarding the presentation:

1. It is confusing that there are conclusions and recommendations at the end of each chapter and 

in Chapter 9, and they are different. For example, at the end of Chapter 5 there is a nine-row 

paragraph with recommendations, while in Chapter 9 these recommendations are expanded to 

ten items over one full page. Also, as another example of confusion, Chapter 5 is called 

Terrestrial Food-Chain Pathway in the text of the report while in Chapter 9 it is referred to as 

Local Produce and Livestock Pathway. A similar thing happens with Chapter 2.

ATSDR Response: To address this comment, we changed “Terrestrial Food-Chain Pathway” 

to “Local Produce and Livestock Pathway” in the Executive Summary and Chapter 5” The 

conclusions and recommendations in Chapter 2 are now consistent with Chapter 9.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-43

[Comment]

2. Consider the first recommendation in Chapter 9 about Chapter 4 Health Outcome Data:

Assess the feasibility of applying the SMART BRFSS methods for generating stable 

Vieques specific prevalence estimates on asthma, diabetes, hypertension, and other 

chronic diseases.

In Chapter 4 the complete Recommendations paragraph reads:

At this time, ATSDR recommends performing additional analyses to quantify cancer 

and noncancer morbidity and mortality, assessment of primary and specialty health 

care needs, and alternative approaches for delivery of health services.

So, in Chapter 9 specific methods come up without any explanation as to what they are, why they 

are better or even needed at all.

ATSDR Response: Assessing the feasibility of SMART to overcome the limitations of 

developing prevalence estimates in a small population should be included as a 

recommendation or next steps in chapter 9. We have made the recommendations in 

Chapter 4 consistent with the recommendations listed in Chapter 9. The language local level 

versus small population is interchangeable. 

Comment]

In Chapter 9 some of the previous chapters have Summary and Conclusions while others only have 

Conclusions. There should be consistency on this to avoid further confusion.

ATSDR Response: Revisions have been made so that the heading reads conclusions.

Select the appropriate category below:

List recommended changes or reasons for not recommending)

o Recommend ( )

o Recommend with Required Changes (X)

o Not Recommended ( )
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-44

[Comment] 

Rewrite the Drinking Water Pathway chapter to better reflect the role of PRASA in supplying the drinking 

water at Vieques.

ATSDR Response: We have modified text in Chapter 8, Section 8.1 to correct any inaccuracy 

regarding the current operators of the public water supply. We did not include detailed 

descriptions of the water supply system. We were concerned it would detract from our 

evaluation of possible exposures from all water supplies, past and present.

Additional Questions:

Are there any comments on ATSDR's peer review process?

[Comment] 

None, except for Question 6 above.

Are there any other comments?

[Comment]

None.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-45

Reviewer 4

Overall, has ATSDR’s re-evaluation of public health issues associated with historical 

bombing exercises at Vieques been appropriate? 

[Comment] This reviewer recognizes and applauds the strong efforts done by the people and 

community leaders of Vieques and of PR to access the health status of its community. In addition, 

congratulates all the researchers that have contributed to the generation of scientific knowledge in this 

area. Overall, the re-evaluation done by ATSDR seems appropriate. This report supports the need for 

additional studies and public health interventions in Vieques, PR, as although some results are still not 

conclusive, evidence supports potential environmental exposures in this population, as well as health 

disparities as compared to the mainland of PR and the United States. Most studies have been included 

in the discussion, although additional efforts should be made to contact researchers whose results have 

not been published. This reviewer has highlighted several issues that merit consideration before this 

manuscript is published (see below).

ATSDR Response: We appreciate all the comments. 

Has ATSDR adequately addressed the pathways of human exposure to bombing rangespecific contaminants?

Please include specific comments on

Consumption of seafood from reefs near Vieques

[Comment] Chapter 2. The ATSDR concludes that children who consumed fish from the reefs near 

Vieques and those born to mothers who also had this consumption were at increased risk for several 

health conditions. Nonetheless, the report highlights that this conclusion about the risk of harmful 

effects to the fetus and to children is somewhat uncertain because a person’s mercury response may 

vary by sex, genetics, health and nutritional status. It is the belief of this reviewer that, despite some 

limitations, the observed association between fish consumption in Vieques and health hazards in these 

population sub-groups is very relevant and should not be minimized. ATSDR should add to its 

recommendations in this area the need for an assessment of the health and nutritional status of 

children in Vieques and how these factors can influence the impact that fish consumption could have on 

the health of children in Vieques. Some information regarding nutritional status of adults and children in 

Vieques could be collected from the BRFSS and the Youth Risk Behavior Survey (YRBS) of PR.

ATSDR Response: Thank you for your comments. 

Children and pregnant women are advised by the U.S. Food and Drug Administration (FDA) to avoid 

eating those fish with the potential for the highest level of mercury contamination (e.g., shark, 

swordfish, king mackerel or tilefish); to eat up to 12 ounces (two average meals) per week of a variety of 

fish and shellfish that are lower in mercury (e.g., canned light tuna, salmon, pollock, catfish); and check 

local advisories about the safety of fish caught in local lakes, rivers and coastal areas. Since fish are 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-46

highly consumed in Vieques, we believe that fish consumption among this population should be 

addressed. 

[Comment]

Table 2-2 (page 17): Efforts should be made to contact Dr. Caro and determine if the data came from dry 

or wet weight fish.

ATSDR Response: Dr. Caro is deceased. The laboratory that conducted the fish analysis for 

her report has not responded to phone calls or e-mails. We have provided additional 

analysis to Dr. Caro’s data in Chapter 2, Section 2.2.1. 

[Comment]

Chapter 2. Given that the authors highlight lack of knowledge regarding the estimation of combined 

doses of exposure (from single and multiple pathways) regarding possible mixture effects for residents 

eating seafood, ATSDR should add to the recommendations of this chapter (and of the overall report) 

that risk from possible mixtures effects for residents eating seafood should be further studied.

ATSDR Response: At this time, evaluation of possible mixtures effects from chemicals in fish 

is not possible because of limitations in the science. This topic is discussed in Chapter 2, 

Section 2.2.6.

[Comment]

Chapter 2.3.2. The list of recommendations on Chapter 2.3.2 could be more specific and describe in 

more detail some of the recommendations previously mentioned in chapter 2. In addition, the authors 

should add to the recommendations of this chapter “Collecting additional fish samples (within each 

family and by reef location) from Vieques.”

ATSDR Response: We provided additional information in Chapter 2 specifying the need to 

collect additional fish samples to allow analysis by species and location.

Use of biomonitoring tools to assess exposure to metals and other hazardous chemicals in 

blood, urine, or hair that are related to historical bombing exercises

[Comment] Chapter 3 (page 50). The authors highlight that the levels of inorganic arsenic in Viequenses 

urine were higher than those reported in the U.S. general population according to the NHANES survey. 

To facilitate the discussion in this section, I suggest adding a table with the values of metals observed in 

the general population of the US according to NHANES. 

ATSDR Response: In Tables 3A-3 and Table 3B-1, ATSDR has included data from NHANES 

showing the average concentration of metals in urine and blood.

[Comment] 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-47

Chapter 3.2 (page 50, fourth paragraph). To complement this first sentence, the authors should include 

a brief summary of the conclusions of the studies by Dr. Colón de Jorge and Dr. Ortiz-Roque. 

ATSDR Response: The conclusions from Dr. Colón de Jorge’s and Dr. Ortiz Roque’s studies 

are presented in the second, third, fifth, and sixth paragraphs in Chapter 3, Section.3.2. No 

changes were made in the Report.

[Comment] Chapter 3. Section 3.5.1 Conclusions: Section does not acknowledge that metals were also 

detected in feces. In addition, sentence 6 of this paragraph starts by saying “Another study weakness...”

Given that this is the only weakness discussed, the sentence should start by saying “A study 

weakness....” 

ATSDR Response: ATSDR has included feces in the list of biological matrices where metals 

were detected and rephrased the discussion about study weakness.

[Comment] Section 3.5.2 (page 56). In the conclusions of this chapter, the authors recommend that 

additional biomonitoring studies should measure mercury levels in blood and hair of Viequenses; these 

studies should also consider other metals and substances in the assessment. The authors should stress 

in this paragraph why additional studies are needed, as presented evidence already suggests high 

mercury levels (and other metals) in hair and blood of Viequenses-suggesting a health hazard in this 

population.

ATSDR Response: ATSDR has added additional information to the Report conclusions in 

Chapter 3. While Dr. Ortiz Roque found several women with elevated levels of mercury in 

hair, the PRDOH study did not show high mercury levels in the blood of 500 Viequenses. 

Some uncertainty therefore remains regarding whether high mercury exposure is prevalent 

on the island. 

[Comment] Section 3.7.1. Summary of Human Biomonitoring, (page 61, third sentence): “These studies 

are briefly mentioned in the main text (not only in this appendix) for Chapter 3 and are described in 

more depth...” The word “depth” should be added to the sentence.

ATSDR Response: ATSDR has reworded this sentence. 

[Comment] Section 3.7.2.2. PRDOH Discussion Phase 1 (bottom of page 65-top of page 66)- Given that 

the authors mention that “At the total population level, the average concentration of some metals was 

above expected norms as established by Quest Laboratories but not above toxic levels as also 

established by Quest Laboratories. The PRDOH manuscript stated that this suggests the need for further 

investigation concerning the various risk factors, with particular emphasis on how smoking contributes 

to metal body burden.” Thus, it is the recommendation of this reviewer that future studies should do a 

complete assessment of tobacco consumption of persons in Vieques. Although data presented in some 

of the analyzed reports does not suggest a higher prevalence of smoking in Vieques than in the rest of 

PR, this data should be analyzed in depth and included in this report. Given that it is of great relevance 

for various topics within this assessment, it should be included or recommended for inclusion in future 

studies in this population?
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-48

ATSDR Response: ATSDR agrees that future studies should include detailed information 

about tobacco use for study participants. Since PRDOH’s 2006 study is confidential, ATSDR is 

unable to obtain the raw data. We are consequently unable to provide more detailed 

information about tobacco use in Vieques. 

[Comment] Section 3.7.2.2 (page 66, line 5)- Regarding the following statement “PRDOH concludes that 

eating fish within 3 days of a test or smoking could partly explain some but not all of the elevated metal 

body burdens in participants.”, the authors should add to the text a discussion of what other potential 

explanations does the PRDOH provide for this result. 

ATSDR Response: ATSDR agrees and has added text to Chapter 3, Sections 3.7.2.2 and 

3.7.4.

[Comment continued] The authors highlight in this appendix that PRDOH data show that “In over 90% of 

the population, detectable levels were found of at least one heavy metal. In more than 20% of the study 

participants, the levels of aluminum in blood, arsenic in urine, and nickel in hair were over the 

laboratory reference threshold. Geometric means for uranium in urine, mercury in blood, lead in blood, 

aluminum in blood, nickel in hair, and cadmium in urine were significantly higher than the geometric 

means from the 1999 NHANES survey.” Nonetheless, the conclusions of chapter 3 recommend 

additional research in this area. A statement highlighting the reasons for these additional studies is 

warranted in the main conclusions/recommendations of this chapter.

ATSDR Response: ATSDR has added clarifying text in the Executive Summary for its

recommendations about future biological sampling and in particular the need for an 

appropriate comparison group. 

[Comment] Section 3.7.5 (page 70). According to the referenced manuscript, the correct sample size of 

the study was 500 participants (not n=499). 

ATSDR Response: The draft PRDOH report uses both numbers as the sample size: 499 and 

500. Which is the correct sample size is unclear. We will use 500.

[Comment] Section 3.7.7.1 (page 76). Results of Dr. Roque regarding the high levels of mercury in the 

hair of Viequense women as compared to those of women in the mainland of PR and the US should be 

highlighted as evidence in the main text. Particularly, given that evidence exists that mercury in hair of 

pregnant mothers is an indicator of disease risk in the fetus. 

ATSDR Response: Dr. Ortiz Roque’s findings are highlighted in the main text of Chapter 3 in 

statements such as these:

Chapter 3, Section 3.2. Dr. Ortiz Roque identified several residents with hair-mercury levels

above 12 ppm—the level the National Research Council identified as causing a 5% 

increase in neurological effects in children who were exposed in utero (NRC 2000). 

Chapter 3, Section 3.7.8.3. Dr. Ortiz Roque’s identification of three residents with hair 

mercury levels above 12 ppm is an important finding.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-49

[Comment] Section 3.7.8.3. Dr. Ortiz Roque’s identification of three residents with hair mercury levels 

above 12 ppm is an important finding.

ATSDR Response: ATSDR agrees that Dr. Ortiz Roque’s findings are important. We have 

made this point several times in Chapter 3. In particular, biomonitoring results from Dr. Ortiz 

Roque showed that some Viequenses had elevated mercury in hair above the level 

identified by the National Academy of Sciences to cause harm in 5% of fetuses exposed in 

utero.

[Comment] Section 3.7.6.2. The manuscript mentions that the PRDOH will develop a protocol for the 

management of persons with suspected acute poisoning of heavy metals using CDC guidelines. What is 

the status of this protocol? Has it been already developed and implemented? The authors could contact 

the PRDOH and include this information as part of the manuscript.

ATSDR Response: ATSDR has been unable to determine whether PRDOH has developed and 

implemented a blood lead survey of Viequense children. 

[Comment] Section 3.7.6.3 (page 73). Table 3A-3 would be enriched by the inclusion of levels of heavy 

metals found in the U.S. population according to NHANES.

ATSDR Response: As suggested, ATSDR has included data from NHANES in Tables 3A-3 and 

3B-1.

[Comment] Section 3.7.8.2 (page 78, line 8). When discussing Dr. Ortiz-Roque’s study, the authors say 

that the non-random participant selection might account for some confounding factor elevating the 

rates. Nonetheless, it should be highlighted that this procedure could also have reduced them.

ATSDR Response: ATSDR agrees that a nonrandom survey could be a confounding factor 

that increases or decrease rates. We have made the suggested change in the text.

[Comment] Section 3.8.3 (page 94). Add reference for the following statement: “Several population 

studies of persons residing in areas with higher cadmium soil concentrations or with cadmium pollution 

have reported mean blood and urine cadmium levels as much as 10 times higher than control groups or 

representative U.S. data.”

ATSDR Response: The paragraph with this statement has been deleted from the report; 

and, the reader is referred to the 4th Report, which contains toxicological information about 

metals.

[Comment] Section 3.8.3 (page 95, first line)- Please include references regarding the impact that 

cadmium levels in blood or urine could have on human health.

ATSDR Response: The paragraph with this statement has been deleted from the report; 

and, the reader is referred to the 4th Report, which contains toxicological information about 

metals.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-50

[Comment] Chapter 4 Summary (page 101). The authors emphasize that “As a result of the small 

population, all studies suffer to some degree from a lack of statistical power and methodological 

limitations that make interpretation difficult. Despite these limitations, the studies are valuable for 

describing the health status of Viequenses. And in Vieques relative to the rest of Puerto Rico, the studies 

indicate elevations in the prevalence of chronic disease, cancer incidence and mortality, and infant 

mortality.” This reviewer disagrees with the statement that interpretation of these studies is difficult. I 

suggest rephrasing this statement.

ATSDR Response: Quantifying differences in rates of morbidity and mortality is statistically 

challenging in small populations. The limitations previously described also introduce 

additional uncertainty. Despite these limitations, the studies are valuable for describing the 

health status of Viequenses. Relative to the rest of the population in Puerto Rico, these 

studies indicate elevations in the prevalence of chronic disease, cancer incidence and 

mortality, and infant mortality in Vieques. 

Consumption of food (produce, meat, dairy, eggs) grown on the island

[Comment] Chapter 5. We agree with the authors in that evidence shows that “Levels of cadmium in 

pigeon peas could be potentially harmful for preschool children who eat more than four 6-ounce 

portions of pigeon peas each week for several years; possibly resulting to health problems later in life.”

ATSDR Response: Thank you for your comment. Relevant text in Section 5.2.2 has been 

revised based on comments received.

Exposure to air, soil, and water on Vieques

[Comment] Section 6.2.1 (page 133, third paragraph). Regarding the Air PHA conclusions, the authors 

mention that the “The Navy’s ordnance exercises at the LIA did not pose a health hazard in the 

residential areas of Vieques.” This statement should be clarified and highlight that it is referring 

specifically to the hazard of residential areas specifically by air pollution (other hazards may still be 

possible through other pathways).

ATSDR Response: The statement referenced summarizes the conclusions of our previous Air 

Public Health Assessment. The current report clarifies this issue (see Chapter 6).

[Comment] Section 6.2.1 (page 134, first bullet). The authors highlight that levels of contaminants in air 

were low, and not at levels that would be associated to disease risk. Regarding the Air PHA conclusions, 

the authors mention that the “Wind-blown dust from the explosive-ordnance range did not and does not 

pose a health hazard to residents.” Comment should be more specific, as contaminants were measured 

in the air, and air quality was not associated to disease risk. This is of particular relevance given that 

cumulative exposure has not been evaluated.

ATSDR Response: As there was no significant transport of airborne contaminants from the 

LIA to the residential areas of Vieques, there was no significant deposition to soils or 

subsequent leaching of contaminants from soil to groundwater. Consequently, the exposure 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-51

pathways for soil and groundwater contaminants (from military operations) are incomplete 

and there is no basis for assessing cumulative exposures for these pathways. The Report 

does discuss the issue of cumulative exposures (as chemical mixtures in fish consumption) in 

Chapter 2, Section 2.2.6 and in Chapter 9, Section 9.9.

[Comment] Section 6.2.3 (page 140). Regarding the following statement in the text: “In addition to the 

recent evaluation of BIP detonations, the Navy has proposed prescribed burning of LIA vegetation to 

access safely and remove remaining unexploded ordnance. In support of this proposal, the Navy has 

conducted additional air modeling to assess the potential effects of such prescribed burning (CH2MHill 

2008a). Although the Air PHA did not address vegetation burning, it did address past operations of open 

burning/open detonation (OBOD) of excess or recovered ordnance. As the mass of ordnance involved in 

past OBOD events was small relative to the mass involved in then-ongoing Naval operations, the 2003 

Air PHA found that air emissions from past OBOD events did not present a public health hazard to the 

residents of Vieques. A permit to allow LIA vegetation burning is pending before the U.S.EPA and the 

Puerto Rico Environmental Quality Board. If so requested by these agencies or by any concerned citizen, 

ATSDR will further evaluate this issue.” Have any requests been done? Do we need to wait for a request 

to do this or is ATSDR recommending that it should be done anyway?

Besides the data presented on Chapter 8 (Drinking Water Pathway), have any effort be made to 

determine the effect of airborne contaminants to water sources?

ATSDR Response: Although ATSDR has not received a specific request to evaluate the 

pending air quality permit, Chapter 6 does include a summary of the air modeling and 

monitoring studies that support the permit application. Those studies indicate that 

vegetation burning in the LIA will not result in harmful inhalation exposures in the 

residential areas of Vieques and are in agreement with the results of the Air PHA. There is 

no public health basis for further evaluation of this issue. We have revised the Report by 

deleting the sentence indicating that ATSDR will further review this issue if so requested.

[Comment] Chapter 7 Summary (page 150). We agree with the authors in the “...need for continuing to 

restrict access to the LIA and to other potentially contaminated military areas until environmental 

assessment and remediation clear the way for unrestricted public access. To address remaining 

uncertainties about residential soil contamination issues, ATSDR recommends surface soil sampling in 

the island’s residential areas.” Particularly as some of the data evaluated is old (from the 1970’s) and 

may not represent the reality of the soil today. Nonetheless, this summary paragraph of chapter 7 

should include the recommendation of soil cleanup (as it does in the chapter-section 7.2.1).

ATSDR Response: Thank you for this comment. We reworded the relevant section of the 

Report, Chapter 7 Summary and in Chapter 9, Section 9.7.2, to clarify that we do 

recommend continuation of environmental assessment and remediation activities.

[Comment] Chapter 7 Section 7.2.1 (page 158). The authors mention that a limitation of the study by 

Garcia (2000) (study that collected soil samples at the LIA and in areas where people lived during 1999-

2000) was that it was missing information on 1) the exact location, depth of sampling, and a 2) complete
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-52

presentation of study results. Did the authors do an effort to contact Garcia and colleagues to clarify this 

missing information? This information is important in this assessment, as the authors are suggesting that 

Garcia’s findings may be biased high (getting this information will clarify if this assumption is in fact 

correct).

ATSDR Response: ATSDR has attempted to contact Dr. Garcia on two different occasions by 

e-mail but has not yet received a response. The authors reported only the highest and nextto-highest detections, so that would by definition high-bias the concentrations.

[Comment] Section 7.2.1 (page 159). Even though the authors conclude that there is no indication that 

protesters living in the LIA in 1999-2000 were exposed to harmful levels of surface soil contaminants, 

they mention that a limitation is that conclusions were based on a small number of samples (making the 

conclusion not valid if future/representative analyses showed something different). This is not 

consistent with their sentence in the Summary section of this chapter (page 149) that says that 

“Sufficient data are available to conclude that people who lived on the LIA during the protests were not 

exposed to soil contaminants at levels high enough to cause adverse health effects.” Although at this 

point evidence does not support risk for this group, the limitation of small sample size should be 

included in the summary statement. 

ATSDR Response: The limitation mentioned in Chapter 7, Section 7.2.1 is a common 

limitation for any environmental characterization. Despite this limitation, the soil data 

collected for protesters living in the LIA were sufficient to characterize potential exposures 

during that time. Samples collected from the protester camp were designed to represent 

actual exposures to those living there. Samples collected from the LIA were collected from 

areas likely to have higher concentrations of contaminants. These samples, although limited 

in number, are reasonable to use as protective descriptors of exposures that might have 

occurred to protesters.

[Comment] Section 7.2.4 (page 164, last 2 sentences). The authors mention that “Yet detection of 

explosive residues in the background samples also suggested that all areas of the island, including the 

residential area, might have been affected by explosive compounds from past bombing activities. 

Although residual levels are low today, it is impossible to say what past levels were.” The authors should 

highlight that although this cannot be corroborated at this point, these exposures may have had an 

impact in the past, this should be highlighted in the conclusions, as right now they are suggesting that 

residential exposure was likely minimal.

ATSDR Response: No changes were made in the report. Although verification is impossible 

regarding past levels of explosives in residential areas, the modeling work described in 

Chapter 6 and the levels of residues in background areas on the land adjacent to the LIA do 

suggest that any past residential exposures were small. 

[Comment] Chapter 8. As recommended by ATSDR, it is the opinion of this reviewer that additional 

studies of the pipelines, wells and rainwater collection systems are needed to confirm the safety of the 

drinking water consumption of Vieques. For groundwater, we agree with the authors in that current 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-53

results do not exclude the possibility for other groundwater contamination caused by military and 

nonmilitary activities hydrogeologically connected to the groundwater that supplies water wells. Thus, 

supporting the need for additional research in this area.

ATSDR Response: Thank you for the comment.

[Comment] Section 8.2.2 (page 172, line 4). The authors mention that “Even assuming the detections 

were present at the level in drinking water, the levels of explosives were too low to result in adverse 

effects (ATSDR, 2001).” What about cumulative exposure? Its possibility and potential harm should be 

acknowledged in the text.

ATSDR Response: No significant transport of airborne contaminants occurred from the LIA 

to the residential areas of Vieques. No significant deposition occurred in soils. Consequently, 

the exposure pathways for air and soil were incomplete; thus assessment of cumulative 

exposures for these pathways was without basis. For drinking water, the health guideline 

values used to compare with the possibly detected levels of explosives in this section were 

chronic guidelines. They would have assumed regular exposure of more than 1 year. But the 

historical data were extremely limited. Using such data to draw definitive public health 

conclusions about past exposures, or about past cumulative exposures, is impossible. The 

Report does discuss the issue of cumulative exposures (as chemical mixtures in fish 

consumption) in Chapter 2, Section 2.2.6 and in Chapter 9, Section 9.9.

[Comment] Section 8.4. Given that several contaminants were found at levels that would make 

groundwater unsuitable for consumption, the need for further studies and cleanup of this sources 

should be highlighted in the summary and recommendations sections of this chapter, as it has been 

done within the chapter.

ATSDR Response: We added recommendations that environmental assessment and cleanup 

of groundwater affected by military operations continue to Chapter 8, Section 8.4.2 and 

Chapter 9, Section 9.8.2 of the Report. 

Does the Vieques summary report adequately present and describe the limitations and 

uncertainty of assessing human exposure to bombing range-specific contaminants?

[Comment] Overall, strengths and limitations of studies seem appropriately discussed in the report. 

Besides the recommendations already provided in this regard, additional specific recommendations are 

provided below. 

Chapter 3 (page 81). Given the relationship between metal toxicities and various diseases and health 

conditions, the report should also include recommendations for additional studies of the effect of metal 

toxicities to: cardiac conditions, cardiovascular, emotional disturbances, violence, poor absorption and 

cancer.

ATSDR Response: Until more information is available that shows contamination of the 

environment with specific metals or explosive compounds and exposure of Viequenses, 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-54

additional recommendations are not warranted to study the effects of metals on various 

health conditions. 

[Comment] Chapter 4, Section 4.1. The correct term is the “Puerto Rico Central Cancer Registry 

(PRCCR),” not the Comprehensive Cancer Registry (PCCPR)

ATSDR Response: We have corrected Chapter 4, Section 4.1 to reflect the Puerto Rico 

Central Cancer Registry.

[Comment] Chapter 4. When describing the PR Cancer Registry, the following statement/reference 

should be added to the text:

“In the year 2003, a CDC audit concluded that 95.3% of all cancer cases 

diagnosed or treated in hospital facilities in PR were appropriately reported to 

the PRCCR; a result comparable to the US median (95%).”

REFERENCE: ORC MacroSM. National Program of Cancer Registries, Technical Assistance and Audit 

Puerto Rico Central Cancer Registry 2000, Case Completeness and Data Quality Audit. Centers for 

Disease Control and Prevention. Department of Health and Human Services; 2003. pp. 1–32.

ATSDR Response: The statement was added to the Report text as the closing statement in 

the paragraph below:

The data reported by the RCCPR have several strengths. Cancer registries 

typically represent the best population-based dataset for any chronic health 

condition. Most cancer cases are captured by registries due to legal reporting 

requirements, redundancies in the reporting system (i.e. reporting by labs, 

clinics, hospitals, and specific oncologists), and the clinical course of most 

cancers that requires substantial follow up and repeated visits. The analysis of 

cancer registry data should then represent the most accurate assessment of 

cancer incidence in Vieques. CDC has continuously funded the cancer registry 

through a cooperative agreement since 1998 and the cancer registry has 

steadily improved its data accuracy. Finally, “in the year 2003, a CDC review 

concluded that 95.3% of all cancer cases diagnosed or treated in hospital 

facilities in PR were appropriately reported to the PRCCR; a result comparable to 

the US median (95%).” 

[Comment] Section 4.1 (page 103). Although not mentioned, another limitation of the BRFSS is that it is 

based on self-reported information. Nonetheless, given that the National Health and Nutrition 

Examination Survey (NHANES) of the US does not collect data for PR, the BRFSS is the best available data 

of population-based morbidity and health behaviors in PR. In order to generate consistent populationbased data of the health status of people living in PR, efforts should be made to include PR (and 

Vieques) in the US NHANES survey. ATSDR could help in these efforts.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-55

ATSDR Response: NHANES is not intended to provide national prevalence estimates. BRFSS 

would thus continue as a better population-based data option for the health status of PR 

residents. 

[Comment] Section 4.2.1 (page 105). The report highlights that all cancer cases in Vieques were ageconfirmed, an activity that could not be done with all cancer cases in PR, where if a case did not have a 

known age, it was not included in any rate calculation. The authors suggest that this could have inflated 

standardized incidence ratios. Is there indication on the PRCCR reports of the percent of cases excluded 

from analyses from the PR mainland due to this reasons? This could give an idea if the potential for bias 

is small or high. If the reports do not specify, this information can be obtained by contacting the PRCCR 

and Dr. Nayda Figueroa. Despite this limitation, mortality rates would not be affected by this, and in fact 

they show higher mortality from certain cancer types in Vieques as compared to PR. This should be 

given higher relevance in the report. In addition, results from this analysis could be better described in 

tables/graphs in order to give the reader a sense of the excess risk observed in Vieques as compared to 

PR.

ATSDR Response: We contacted Dr. Figueroa to obtain information on the percentage of 

cases in PR that were excluded from analyses because of the lack of age confirmatory data. 

We have not heard back from Dr. Figueroa, and therefore have nothing to add to this 

response at this time. We are continuing to follow up.

The magnitude of the combined effect of excluding cases from Puerto Rico and actively 

seeking out cases in Vieques and not in Puerto Rico would make the SIR higher than if the 

limitations mentioned were not present. The magnitude of this bias is unclear—it may or 

may not change the overall conclusions. We agree that mortality for certain cancer types is 

higher in Vieques than in Puerto Rico. Although mortality is an important measure of health 

status, we believe that disease incidence is a better measure than is mortality for assessing 

whether military activities affected Viequenses’ health. 

[Comment] Section 4.2.2 (Page 105). The authors say that the demographics in 2 of the 4 communities 

studied by Lopez and Carrosquillo (2002) in the study appear unusual. On what basis the authors 

conclude this and why is this a limitation of the study? The demographics of Vieques are in fact different 

from those of PR, a reference from the Census that supports this statement should be included. 

ATSDR Response: A review of the 1990 and 2000 census data showed that the selected 

sample population was older than the population in Vieques. Also, only persons ages 5–25 

were selected from Lujan, and only older persons ages 59 –70 were selected from Puerto 

Rico Reconstruction Administration PRRA. The percentage of people in the sample 

population who were 60 years of age or older appears to be higher than the percentage of 

people in that same age category based on data from the 1990–2000 census report. This is 

not a limitation, but an inconsistency that we observed. 

[Comment] Table 4.1 could be strengthened by including in the table the percent of persons that were 

affected with each of the health conditions (Lopez and Carrosquillo 2002).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-56

ATSDR Response: The percent of persons affected was added to Table 4.1 as suggested.

[Comment] Section 4.2.4 (page 107). A better description of the results obtained in the study by Roque 

(2002) could be included in this section. On this page, the following statement should be highlighted as a 

strength: “Typically, mortality data are population-based, with near universal coverage, and are less 

prone to bias.” 

ATSDR Response: Our statements about the strengths of mortality data were intended to 

apply for both the cancer registry and for Dr. Ortiz Roque. We modified the paragraph to 

make this point clearer. Mortality data reported by RCCPR and Ortiz Roque may also provide 

meaningful insight into the health status of Viequenses and have several strengths. 

Typically, mortality data are population-based, with near universal coverage, and are less 

prone to bias. Analyses of mortality patterns in a population can be useful for hypothesis 

generation. But using these data to quantify potential relationships in exposure-disease 

relationships has limitations. Many potential confounding variables are not susceptible to 

assessment (e.g., access to care, lifestyle factors, and dietary habits). 

[Comment] Section 4.2.2 (page 108). Was an effort made to contact the study researchers of the Lopez 

Carosquillo study and get information of the confidence intervals for the risk ratio estimates to identify 

differences? Despite the lack of confidence intervals, the magnitude of the excess risk observed in this 

study should be considered a strength that supports the greater disease burden in Vieques as compared 

to PR.

ATSDR Response: We did not attempt to contact researchers to obtain confidence intervals 

for this review. We relied on the reports as written and commented on strengths and 

weaknesses of the methods used to produce results. 

[Comment] Section 4.2.4 (page 108, line 15)-The authors say that “Finally, whether the Puerto Rico 

disease prevalence data was used as a reference from the PRCMS or some other source is unclear—the 

PRCMS was based on systematic self-reporting mechanisms (e.g. , the Behavioral Risk Factor 

Surveillance System).” This statement is not clear to this reviewer. The PRCMS data is based on the 

Continuous survey of PR (See page 15 of the Lopez and Carosqullo study, 2002). 

ATSDR Response: This statement was deleted. At the time of our initial draft of this report, 

we did not have a copy of the 1994 Annual Survey. 

[Comment] Section 4.3 Findings (page 108). Please add to this section information on the PRCCR report 

of 2009, as it does not seem to have been addressed.

ATSDR Response: The findings reported in 5-year intervals (1990–1994, 1995–1999, 2000–

2004) are from the 2009 report. We added tables to make this more apparent.

[Comment] Section 4.3 (page 109). Authors suggest that the fact that 36% of participants from the Lopez 

and Carrosquillo (2002) study were unemployed may have implications for lack of insurance coverage 

and access to appropriate medical care, thus affecting morbidity and mortality data. Even though this 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-57

may be in part true, the authors should acknowledge that approximately 90% of the population of PR 

are insured, and close to 40% of the population of PR are covered by Reforma (the public, government 

funded health insurance program). Thus, most unemployed people will in fact have access to health care 

through Reforma. Nonetheless, physical barriers (such as lack of proximity to health care providers) does 

exist for residents of Vieques. 

ATSDR Response: Of the participants in the Lopez and Carrosquillo (2002) study, 36% were 

unemployed. Although these participants may have access to health care through the 

government funded health program, their implications may be due to the lack of access to 

specialty care, thus affecting morbidity and mortality data. 

[Comment] Section 4.4.2 (page 110). Contrary to what is expressed by the authors “The limitations 

associated with these analyses, particularly the methodological concerns discussed in this report, 

introduce considerable uncertainty and make interpretation difficult. These findings can nonetheless 

serve as a guide for future investigations of Viequenses health status.” This reviewer believes that the 

data provided suggests evidence of a higher burden of chronic disease in the population of Vieques as 

compared to PR. The recommendations for the section of “Health Outcomes” seem vague. What are the 

specific recommendations in this area? There is enough evidence to support higher cancer incidence 

and particularly mortality among people residing in Vieques as compared to PR. What are the specific 

recommendations regarding future studies in this area? Also, additional future studies of chronic disease 

prevalence in Vieques as compared to PR should be added to the list of recommendations in this 

section.

ATSDR Response: We agree that the health outcome data suggest a higher burden of 

disease in the population of Vieques as compared with Puerto Rico. But we also believe that 

the limitations in the available data reduce the strength of these conclusions. The limitations 

include the completeness of the Registry for much of the period of analysis and the selfreported data from the symptom prevalence survey. We believe that the next steps should 

focus on studies that better define exposure and that better characterize the occurrence of 

cancer and noncancer morbidity and mortality. ATSDR plans to consult with the community 

in Vieques, scientists in Puerto Rico, public health officials, and other external stakeholders 

to determine recommended, specific studies.

[Comment] Chapter 6. Page 131 (second paragraph). Could the air-sampling studies performed in the 

1970’s by the Navy be biased given that they were not corroborated or validated by an independent 

group? Is there any way to validate this data?

ATSDR Response: The 2003 Air PHA included a comprehensive review of historic data, 

including a determination of their utility as a basis for public health determinations. The Air 

PHA determined an adequately post facto data quality assessment was impossible. We 

consequently developed an air modeling study to assess historic exposures. The results of 

the air modeling study are consistent with all of the air monitoring studies and collectively 

provide an adequate basis for the public health conclusions.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-58

Are independent studies utilized appropriately in the determination of potential health 

hazards?

[Comment] Overall, independent studies have been used appropriately in the determination of health 

hazards. Most studies have been included in the discussion, although additional efforts should be made 

to contact researchers whose results have not been published. In addition, as it has been already 

mentioned in this evaluation, additional efforts should be made to get specific unavailable information 

from some of these studies, as it is very relevant for a complete assessment. Also, as previously stated, 

results from the section of Health Outcomes seem strong, and should be acknowledged as so in that 

Chapter. Additional recommendations are described below.

Even though on section 2.5.1 (page 34) the authors say that “By collecting only larger species, the 

average concentrations might have been biased high, which might have resulted in a mercury 

overestimate” , they later says (page 35) that the “School of environmental matters collected 52 fish of 

varying sizes..” These statements seem inconsistent, please clarify.

ATSDR Response: Chapter 2 discusses two fish sampling plans, one from ATSDR and the 

other from Dr. Caro. ATSDR attempted to capture larger fish because larger fish tend to 

have higher contaminant concentrations. ATSDR’s sample of various fish species might 

therefore show high-biased mercury levels. We intended this bias so that ATSDR would be 

sure to sample fish with higher contaminant levels. Dr. Caro reported that she could not find 

an association between mercury content and fish size. She attributed this lack of association 

to the predominance of smaller fish in her study. We provided additional information about 

Dr. Caro and ATSDR’s fish data in Chapter 2, Sections 2.2.1 and 2.2.2. 

[Comment] Section 2.5.6 (page 38). Authors mention that “Table C1 in Appendix C of U.S.EPA (2001a) 

includes a complete summary of all comparisons between locations, parametric and nonparametric, for 

all species.” For the convenience of the readers, please consider including this table as an appendix to 

this manuscript. 

ATSDR Response: As requested, Table C1 from U.S.EPA’s analytical report of ATSDR’s 2001 

fish sample has been added to the Report, Chapter 2, Section 2.5.6.

[Comment] Chapter 4. PRCCR data and the Lopez Carrosquillo study could be further discussed in this 

chapter (see previous comments). In addition, other references cited in this paper by Lopez and 

Carrosquillo (2002) seem relevant to the assessment in discussion, and should be considered for 

inclusion in this report.

ATSDR Response The references mentioned in the Lopez and Carrosquillo paper did not 

provide any additional information on morbidity and mortality other than what we obtained 

previously from other reports. 

Chapter 4. The 2009 report of the PRCCR, which evaluated cancer incidence and mortality from 1990–

2004, is not summarized in the Appendix of this manuscript. Please include. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-59

ATSDR Response: We added a summary of the 2009 PRCCR report to Appendix A.

[Comment] The study by Dr. Carlos Rodríguez Sierra regarding arsenic levels in people of Vieques (page 

272) is very relevant for biomonitoring. Further efforts should be made by the authors to contact Dr. 

Rodríguez Sierra and get a copy of his results for further discussion in this report. 

ATSDR Response: On September 23, 2010, Dr. Rodríguez Sierra responded to our request 

for additional information about his arsenic studies with this statement:

“Regarding the results of arsenic in Vieques, we just submitted this work as a 

research manuscript to a journal to be evaluated for publication (waiting time is 

6-10 weeks).”

If the study is accepted for publication, it should be available in 2011. Dr. Rodríguez Sierra 

has repeatedly declined to share his data with ATSDR—that he wishes to publish the data 

first is understandable. Until his data are available, ATSDR will use the results he presented 

in his Webinar for qualitative purposes only.

On the basis of ATSDR’s –re-evaluation of historical bombing activities in the Vieques 

summary report, has ATSDR reached the appropriate conclusions and recommendations?

[Comment] Despite some limitations characteristic of research studies, previous research suggests a high 

burden of environmental health risks and of chronic conditions in the Viequense population. This 

reviewer overall agrees with recommendations/conclusions made in Chapter 9 of this manuscript. 

Nonetheless, specific suggestions are described below.

Fish pathway:

Given that this manuscript shows potential health risks associated with the consumption of large 

amounts of fish in Vieques, this reviewer agrees with the proposed recommendations of additional 

conclusive studies in this area. These future studies should consider fishes of different sizes, different 

classes of fish within the same family species and from different reef locations. 

ATSDR Response: We added the concept of looking at fish species and locations to the 

recommendation for an additional fish study. See Chapters 2 and 9.

[Comment]

Biomonitoring: 

Increased blood levels of mercury in blood and hair of Viequenses has already been documented. Given

that some limitations have been discussed in the text regarding this data, the authors should clarify in 

the recommendations of this chapter (Chapter 9) why they are suggesting additional studies. 

ATSDR Response: We have recommended that a survey of Vieques residents be conducted 

to determine the types, frequency, and quantity of fish consumed. The results of this survey 

could be used to conduct additional risk assessments and statistical analyses to validate our 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-60

concerns about mercury in Vieques reef fish. Although ATSDR is not recommending a 

comprehensive, systematic biomonitoring effort at this time, public health officials could 

consider a limited and focused human biomonitoring investigation following the release of 

this report. If a biomonitoring investigation is conducted, it should include a comparison 

group from mainland Puerto Rico. If requested, CDC/ATSDR subject matter experts will 

provide technical assistance and support to PRDOH in planning and conducting such an 

investigation

We have recommended that if individual Viequenses remain concerned about exposure to 

mercury, cadmium, other metals, or metalloids, they should consult their healthcare

provider to discuss the need for and cost of testing. A qualified laboratory should do the 

testing and analysis.

[Comment]

Health Outcome Data

Increased burden of chronic diseases, cancer incidence and cancer mortality are documented in Vieques 

as compared to PR. The authors suggest that the confidence intervals are too wide. To what study are 

they making reference when doing this comment?

ATSDR Response: We are referring to the last line of paragraph 2 on page 56 of the 2009 

Cancer Incidence and Mortality report, which refers to low precision in the confidence 

intervals. We added language to clarify our reference to cancer incidence and mortality in 

Chapter 9, Section 9.4.1. The revised response refers to cancer incidence and mortality. 

Uncertainty is also evident in the wide confidence intervals reported indicating imprecise 

estimates of cancer incidence and mortality ratios in Vieques relative to the rest of Puerto 

Rico (RCCPR 2009).

[Comment]

Section 9.4.2 (page 191, 4th recommendation). Why do they suggest point 4?? The data already provide 

evidence of increased disease risk in this population. Please provide more specific recommendations of 

the reasons for future studies in this area, and the suggested qualities/focus that these studies should 

have. 

ATSDR Response: Although the data suggest increased prevalence of chronic diseases, we 

believe the findings contain considerable uncertainty. The conclusions for the prevalence of 

noncancer chronic diseases are based solely on one report. We believe that the next steps 

should focus on studies that better define exposure and that better characterize the 

occurrence of cancer and noncancer morbidity and mortality. 

[Comment]

Local Produce and local Livestock Pathway
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-61

Given that evidence suggests potential contamination of foods (i.e. pigeon peas), potential for uptake of 

metals from soil into local food crops, and lack of definite data on contamination of edible portions of 

produce and livestock, this reviewer agrees with the recommendation of further sampling and research 

in this area. The splitting of samples between labs for further validation of results is an important 

suggestion.

ATSDR Response: Thank you for your comment.

[Comment]

Air Pathway:

Is there any way to confirm the U.S. Navy records of the types and amounts of ordnance used at the 

training range? Fluctuations in this records could impact the models developed to access population 

exposure

ATSDR Response: The 2003 Air PHA included a comprehensive review of the Navy’s 

ordnance usage data and metals and explosive by-products emissions estimates that ATSDR 

derived from them. While there is no way to provide an ordnance usage estimate 

independent of naval records it should be noted that the Navy does not keep such records 

for environmental assessment purposes. The Navy maintains ordnance usage data for the 

purpose of monitoring training activities and ultimately because they must replace 

expended ordnance. Consequently, there is little rationale for the Navy to underestimate 

ordnance usage.

[Comment]

The report concludes no potential exposure to residential areas and thus, no further research in this 

area. Given that this reviewer is not an expert in Air pathways, the feedback of another reviewer in this 

area is recommended.

ATSDR Response: Comment noted. 

[Comment]

Soil Pathway:

The results presented in this chapter suggest that contaminant levels at the LIA may have in the past 

been high, and are potentially high in the present, and thus may represent a harm for human exposure. 

Thus, this reviewer agrees with the need of future studies in this area. Validation of samples between 

laboratories should be done during these efforts. 

ATSDR Response: Thank you for your comment.

[Comment]

Drinking Water Pathway:
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-62

I agree with the recommendation of additional research to further sample drinking water in Vieques to 

determine the safety of its consumption. 

ATSDR Response: Thank you for your comment.

[Comment]

Section 9.9- Final Summary

The authors suggest the need for a well-conceived and well-conducted biomonitoring study. They 

should further elaborate on the proposed characteristics for this study, including that it should have the 

capacity to study mixtures and cumulative exposures and their impact on human health in Vieques.

ATSDR Response: In this type of document, elaboration is not appropriate regarding the 

study design of any future biomonitoring study in Vieques. A more appropriate approach is 

first to gather buy-in from scientists and health professionals who would be interested in 

such a study. After identifying such a group or groups, much discussion would be needed to 

determine the metals and other compounds that could be monitored and that could provide 

insight into whether residents are being exposed to contaminants from past military 

exercises. Adding mixtures to such a study would require a great deal more thought and 

insight. Many reviewers commented that one failing of the previous studies and work on 

Vieques was the inability to relate contaminants to bombs and munitions. Thus identifying 

which metals are military exercise-related is important, as is whether a pathway of exposure 

can be identified that warrants a biomonitoring study. Although ATSDR is not 

recommending a comprehensive, systematic biomonitoring effort at this time, public health 

officials could consider a limited and focused human biomonitoring investigation following 

the release of this report. If a biomonitoring investigation is conducted, it should include a 

comparison group from mainland Puerto Rico. If requested, CDC/ATSDR subject matter 

experts will provide technical assistance and support to PRDOH in planning and conducting 

such an investigation. The Report does discuss the issue of cumulative exposures (as 

chemical mixtures in fish consumption) in Chapter 2, Section 2.2.6 and in Chapter 9, Section 

9.9. No change was made in the Report.

Select the appropriate category below:

List recommended changes or reasons for not recommending)

o Recommend ( )

o Recommend with Required Changes (X)

o Not Recommended ( )

Additional Questions:

Are there any comments on ATSDR's peer review process?
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-63

[Comment] This report acknowledges the commitment of ATSDR in its continuing involvement in 

Vieques and in continuing to work with local community and health and environmental officials to 

implement the recommendations of this report. This reviewer thinks that this commitment is essential, 

not only in expertise, but also in other recourses, such as financial matters (as a future, well-rounded 

study will be costly).

ATSDR Response: Thank you for your comment.

Are there any other comments?

[Comment] The following terms (and others) should be abbreviated on their first use in the text, then 

the abbreviation should be used consistently throughout the document. 

Live impact area (LIA) 

Puerto Rico Department of Health (PRDOH)

National Research Council (NRC)

Nuclear regulatory commission (NCR)

Eastern Maneuver Area (EMA)

National Health and Nutrition Examination Survey (NHANES)

ATSDR Response: Thank you for your comment. Changes have been made as appropriate.

[Comment] Section 2.2.1 (page 16). The correct term is Parguera (not Parquera), an area located at the 

west of Puerto Rico’s mainland.

ATSDR Response: We have corrected the spelling.

[Comment] Section 3.3 (page 52). A description of the NHANES survey is done on page 52, although the 

study is mentioned previously in the text. Its description should come earlier.

ATSDR Response: The use of NHANES has been corrected.

[Comment] Section 3.4.1 (page 55). When the authors suggest that before hair analysis could become a 

valid diagnostic tool for any particular substance, research needed to ”to”...4) learn more about organic 

compounds in hair.” Please specify what kind of knowledge is suggested in this area. 

ATSDR Response: This type of discussion is beyond the scope of this report.

[Comment] Section 3.4.2 (page 55). Add reference for the report of the 2005 German Federal 

Environment Agency report.

ATSDR Response: The reference is included in the reference section to Chapter 3 and in the 

text (see GFEA 2005 in Section 3.4.2). No change in the report is needed.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-64

[Comment] The results of this manuscript should be discussed with researchers, community leaders, the 

Department of Health of Puerto Rico and other people interested in the health of Vieques for further 

evaluation and recommendations. Multidisciplinary and collaborative efforts should be developed to 

further study and improve the health of this community. 

ATSDR Response: Thank you for your comment. ATSDR plans to work with our partners to 

discuss the implementation of the Report’s recommendations.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-65

Reviewer 5

Overall, has ATSDR’s re-evaluation of public health issues associated with historical 

bombing exercises at Vieques been appropriate? 

ATSDR Note: Peer Reviewer 5 did not answer the six questions that were sent, but rather 

provided comments in the format below. ATSDR has provided responses to the comments 

after each comment where appropriate.

[Comment]

Critique of Air Pathway Analysis:

1. Failure to Collect and Manage Air Pollution Data: ATSDR concluded that air pollution data was 

mismanaged and therefore provides unreliable information regarding the magnitude and 

distribution of air contaminants during high activity periods on the Live Impact Area.

The Navy's 1979 Environmental Impact Statement (EIS) for continued use of the bombing range

documents results from a 2-month air sampling program (TAMS 1979 provided no information

on the sampling methods used or on data quality. No documentation can be found describing

the sampling methods used or the quality assurance measures taken.

ATSDR Response: Quality of data used in the assessment: The Air PHA included a 

comprehensive review of all of the available air monitoring data, modeling studies, and 

meteorological data. While historic data and data reports do not include all of the data 

quality assessments that are required in current practice, this does not preclude the use of 

such historic data. Such data, however, should be interpreted with caution. The Air PHA 

used the historic data in conjunction with recent monitoring data and modeling studies. 

Although in isolation each of these information sources includes aspects of uncertainty, 

collectively they provide a comprehensive assessment of the potential airborne exposures in 

the residential areas of Vieques. 

[Comment]

Exposures to Releases from Military Training Exercises Using "Live" Bombs

Averaging Periods: A problem is identified with respect to air pollution modeling. Pollution levels were 

averaged over two periods, one year and 24 hours. This may be relevant for chronic respiratory disease 

prevalence, however it neglects the potential for short term bursts of pollution to exacerbate existing 

respiratory problems such as asthma, allergies and chronic bronchitis. Averaging pollution over 24 hours 

could make temporal bursts caused by periodic explosions disappear, while these episodes may be quite 

relevant to estimating respiratory distress among the sensitive. This is especially problematic for young 

children who have immature and narrower airways than adults. 

ATSDR Response: The reviewer is correct in noting that there was no assessment of PM10 

concentrations for time periods fewer than 24 hours, and that military operations could 

have resulted in higher PM10 concentrations for time periods of fewer than 24 hours. The 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-66

U.S.EPA and the California Air Review Board have established recommended procedures for 

converting between various air loading averaging periods (USEPA 1992; CA ARB 1994). The 

recommended conversion to estimate a 1-hour averaging period from a 24-hour period is to 

multiply the 24-hr value by 2.5 (Figure H.1/ Appendix H, CA ARB, 1994). 

Using the upper-bound assumptions for contaminant emissions, daily ordnance use, and 

meteorological transport conditions, the ATSDR Air PHA estimated that “live bombs caused 

the 24-hour average PM10 concentrations in residential areas to increase by 10.2 μg/m3“ 

(page 40, Air PHA). Using the above conversion procedure, the maximum 1-hour increase in 

PM10 would be 25.5 μg/m3(10.2 μg/m3x 2.5). Adding the calculated maximum 1-hour 

increase of 25.5 μg/m3 to the maximum 24 hour measured PM10 concentration (94 μg/m3; 

Isabel Segunda, page C-9, Air PHA) results in a maximum short-term air PM10 concentration 

of 119.5 μg/m3. This value is below the 24-hour PM10 standard of 150 μg/m3and unlikely to 

result in respiratory distress or other adverse health effects. As shorter averaging periods do 

not change the health determination, no changes to document have been made as a result 

of this comment.

[Comment]

2. Particle Size: Low diameter particles (less than 2.5 microns in size) were not measured. These 

fine and ultrafine particles may stay suspended for longer periods of time, move longer 

distances and may become more deeply embedded in the lungs. 

ATSDR Response: Chapter 6, Section 6.2.2 (of the summary document explicitly addressed 

the issue of PM2.5. No further revisions are necessary. 

3. Wind Blown Dust: It was concluded that wind-blown dust from the LIA on days when bombing 

did not take place is not a health hazard.

ATSDR Response: Thank you for your comment.

4. Total Suspended Particulates (TSP) are primarily a measure of larger diameter airborne particles 

that would likely settle out in close proximity to the location of their generation. Particles of 

smaller diameter—PM 2.5 microns in diameter and smaller—are far more likely to remain in the 

atmosphere for longer periods of time and travel longer distances before deposition. These finer 

particles were not measured by ATSDR, the Navy or EPA. These particles may also act as nuclei 

for other hazardous VOC’s. 

ATSDR Response: Chapter 6, Section 6.2.2 of the summary document explicitly addressed 

the issue of PM2.5. No further revisions are necessary. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-67

[Comment]

5. Chaff: Chaff fibers typically are 25 microns (μm) thick and between 1 and 2 centimeters long. 

Chaff fibers are visible to the human eye and have the appearance of short, very fine, hair-like 

fibers. 

a. ATSDR estimates that 266,000 pounds/year of chaff may have been deliberately dropped over 

or near Vieques. 

b. Ground level concentrations were never monitored by the Navy or other government 

authorities. 

ATSDR Response – Chaff: Regarding the issue of chaff emissions and exposures, the Air PHA 

explicitly addressed the issue of chaff emissions and potential exposures. Using health 

protective assumptions regarding emissions, exposure, and uptake, the Air PHA concluded 

that “...the usage of chaff at Vieques does not pose a public health hazard, whether the 

chaff particles are inhaled or deposited in the mouth and swallowed.” The Report 

summarizes this finding regarding chaff and other air contaminants in Chapter 6, Section 

6.2.1. No further revisions or assessment are necessary.

[Comment]

Critique of Drinking Water Analysis

[Comment]

1. Chemicals released to the environment of the island of Vieques by the U.S. Navy may have 

resulted in human exposure and associated health threats that may be dose dependent. A 35 

year period between 1943 and 1978 is the most likely time when the island’s population was 

exposed via drinking water to possible hazardous compounds released to the environment by 

the Navy. Yet this is also a period when government testing of environmental quality on the 

island was minimal.

ATSDR Response: The current conclusion that a lack of historical data prevents a definitive 

conclusion about distant-past exposures to drinking water from wells is consistent with this 

comment; therefore, no changes have been made. We believe, however, it is important to 

indicate what limited past information and data do tell us about the relative likelihood of 

past exposures through the drinking water pathway. As discussed in Chapter 1, Section 1.2, 

ordnance training on Vieques was not scaled up until the 1970s, particularly after 1975, 

when training on the island of Culebra was discontinued. Therefore, it is not unreasonable 

to presume that contamination of public supply wells or cisterns was very unlikely before 

the mid-1970s.

2. [Comment] The poor history and quality of water testing makes it difficult to precisely 

reconstruct a history of exposure. Water supplies were not routinely tested for chemicals that 

were released to the environment by the Navy. 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-68

ATSDR Response: The problem of limited historical environmental monitoring data is not 

specific to Vieques. It is common at many sites that operated in the past. ATSDR evaluates public 

health effects from potential past exposures in such situations by reviewing available 

contaminant fate and transport data and, using professional judgment, making assumptions 

about past exposure and identifying areas of uncertainty.

3. [Comment] The most probable routes of exposure to chemicals released to the Vieques 

environment by the Navy include: 1) contamination of drinking water wells from airborne 

chemicals that drifted and settled in the watersheds surrounding municipal wells; 2) 

contamination of cisterns from airborne chemicals that drifted and settled into the tanks; 3) 

contamination from Naval use of pesticides and herbicides; 4) contamination from airborne and 

surface fuel releases; 5) waste disposal practices. 

ATSDR Response: Thank you for this comment. ATSDR’s drinking water PHA and Chapter 8 

of this report discuss contamination of drinking water wells and cisterns (rainwater 

collection systems). Potential sources of contamination, including use of pesticides or 

herbicides, releases of fuels, and waste disposal practices, are evaluated by evaluating levels 

of associated contaminants in air, soil, or drinking water, as was done in past ATSDR PHAs 

and this report. 

4. [Comment] Most reported studies are not peer reviewed, remain unpublished and are often 

based upon sampling designs and exceptionally small sample sizes (ranging between 1-12 

samples). Degradation products were not tested or reported. 

ATSDR Response: ATSDR summarized the findings, strengths, and limitations of the 

reviewed studies in Appendix A of the Report. ATSDR was requested to review all available 

studies and data related to potential exposures at Vieques. While many of the studies were 

limited, they added to the body of knowledge about Vieques environmental exposures. 

5. [Comment] Since the ATSDR drinking water study was completed prior to the air study the 

conclusions of this report are not conclusive. The most plausible pathway for drinking water 

contamination resulting from Navy activity on the islands is from airborne chemicals having 

settled in drinking water systems. 

ATSDR Response: As described in Chapter 6 and detailed in ATSDR’s Air Pathway Public 

Health Assessment (2003), evaluation of the air pathway suggested that no substantial 

levels of atmospheric contamination had reached the residential area of Vieques. ATSDR 

was unable to evaluate directly the potential for exposures from cistern water as no cistern 

water data are available.

6. [Comment] These studies do not provide a reasonable estimate of the drinking water 

contamination that may have occurred prior to the completion of the municipal water supply 

line from the main island of Puerto Rico in 1978. 

ATSDR Response: As concluded in Chapter 8, Section 8.4.1 and Chapter 9, Section 9.8.1, 

ATSDR recognizes that the 1978 data are insufficient to make public health conclusions 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-69

about exposures long past. But as detailed in Chapters 6 and 8, consideration of 

groundwater flow patterns, air modeling studies, actual bombing patterns, and recent 

sampling results suggest that past exposures from drinking water were not high.

7. [Comment] The EPA studies cited did not test for pesticides and herbicides. Also an analysis of 

military use of pesticides and herbicides not been conducted or presented.

ATSDR Response: The Report does not consider pesticides and herbicides. As discussed in 

ATSDR’s Drinking Water Pathway PHA (2001), 1995 sampling had shown no detections of a 

wide range of pesticides and herbicides, indicating that drinking water supplies had not 

been contaminated at any location by pesticides or herbicides. Pesticides and herbicides 

were not analyzed in many of the soil sampling events. Soil sampling at the NASD and recent 

EMA sampling related to remediation activities have found a few detections of DDT and its 

breakdown products. In all but one specific location, these detections were far below 

health-based comparison values; one location had detections higher than comparison 

values. ATSDR’s recommendation to restrict the LIA and other potentially contaminated 

military areas and continue environmental assessment and remediation activities will 

protect the public from any harmful exposures to pesticides and herbicides remaining from 

military activities. 

8. [Comment] It was reported the presence of RDX (0.04 ppb) and Tetryl (0.05) in the drinking 

water supplies of Isabel Segunda (0.5 ppb) and RDX (0.04 ppb) in the drinking water of 

Esperanza in May of 1978, referencing a Naval Surface Weapons Center report (Hoffsommer 

and Glover 1978; Lai 1978). 

ATSDR Response: ATSDR discussed these findings in Chapter 8, Sections 8.2.2 and 8.3.1.2 of 

the Report.

9. [Comment] The studies interpreted by ATSDR do not demonstrate the absence of health threats 

associated with naval activities. Instead, they demonstrate the absence of proper testing of the 

community’s drinking water supplies at a time in its history when it was most vulnerable. 

ATSDR Response: As concluded in Chapter 8, Section 8.4.1 and Chapter 9, Section 9.8.1, 

ATSDR recognizes that the 1978 data are insufficient to make public health conclusions 

about distant past exposures.

Critique of Soil Analysis:

1. [Comment] Failure to Collect and Manage Soil Contamination Data: The Navy consistently failed 

to collect data on soil contamination associated with training and operations. The absence of 

these data prevented the understanding when and where possible soil contamination might 

have posed a public health threat. This could occur from particles exploding into the 

atmosphere, drifting along the island into the breathing zone of inhabitants, settling on soils, 

infiltrating water supplies, being absorbed by plants, some of which might have been consumed 

by animals, in turn consumed by humans. By failing to monitor pollution air pollution, patterns 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-70

of deposition to soil and other sediments, this in turn prevented an understanding of possible 

food chain dynamics. 

ATSDR Response: We agree that the issue of food-chain dynamics has not been thoroughly 

investigated on Vieques. Long-range transport of certain contaminants (e.g., aerial 

deposition of mercury) has been observed elsewhere under the right conditions (i.e., 

continuous emissions of large quantities from a single large source or multiple smaller 

sources, combined with appropriate meteorological conditions). Nevertheless, actual 

sampling data and air dispersion modeling on Vieques do not indicate that environmental 

transport of contamination originating from the bombing areas would be expected to affect 

areas distant from the range. It appears that any environmental effect from past range use 

activities is localized.

2. [Comment] Grazing Animals and their Products: The Navy, EPA and ATSDR did not do research 

on grazing activities by cattle, goats, sheep, pigs and chickens. Their importance to the diet of 

Viequenses is also poorly understood, but could potentially be an important additional pathway 

of contaminant exposure. The community members expressed concern over the possibility that 

livestock are accumulating heavy metals by grazing on contaminated plants.

ATSDR Response: Thank you for your comment. At the time of the original public health 

assessment discussing the soil evaluation pathway, little information or data were available 

pertaining to the potential for heavy metal accumulation in local livestock. The Puerto Rico 

Department of Agriculture, in cooperation with the Farmers Association of Puerto Rico, 

sampled grass, fruit-bearing trees, and bovine livestock from Monte Carmelo, Martineau, 

Monte Santo, Esperanza, Lujan, Gubeo, and western Vieques for cadmium, cobalt, copper, 

lead, manganese, and nickel. They concluded that the agricultural products from Vieques 

did not contain toxic levels of these contaminants and were suitable for consumption (El 

Nuevo Día 2001).

Since that time, additional plant data have been collected. But due to data limitations, 

uncertainty remains regarding the degree of potential exposures from consuming local 

produce. The Report contains a thorough discussion of currently available sampling data 

from locally produce and livestock. Although the results of sampling by the Puerto Rico 

Department of Agriculture is reassuring, ATSDR recommends additional sampling of locally 

grown produce to allow a more complete evaluation of this exposure pathway. 

3. [Comment] Air, Soil and Water: The most plausible hypothesis regarding transport and fate of 

chemicals is that chemicals released to the atmosphere were eventually deposited on soils and 

plants and then washed into underlying aquifers by rains. 

ATSDR Response: To assess whether the dust releases present public health hazards, ATSDR 

evaluated whether dusts blow into the residential areas in appreciable quantities. The 

findings of the Air Pathway Evaluation, described in Chapter 6, suggest that substantial 

levels of atmospheric contamination had not reached the residential area of Vieques.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-71

4. [Comment] Plant Contamination: ATSDR could not quantify exposures to contaminants from 

these reports nor draw any health conclusions about whether consuming plants grown in 

Vieques would result in harmful health effects. 

ATSDR Response: Most of the relevant studies sampled plant species typically not eaten by 

humans or sampled the parts not eaten. As a result, the data were not useful for 

interpreting the degree of exposure or representative of locally grown produce on the 

island. To address this data gap, ATSDR recommends further sampling.

An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-73

Reviewer 6

Overall, has ATSDR’s re-evaluation of public health issues associated with historical 

bombing exercises at Vieques been appropriate? 

[Comment] According to my best knowledge, the ATSDR re-evaluation of public health issues associated 

with historical bombing exercises at Vieques is appropriate. This opinion is based on the evidence 

presented, including ATSDR own data and the data generated by Puerto Rican scientists and 

researchers. As ATSDR recognizes, there is a huge degree of uncertainty in this type of analysis and the 

recommendations made are directed to reduce that uncertainty. Vieques was used as a military target 

and ammunition-explosive storage for more than 60 years and, as expected, these military activities are 

a major source of contamination, which constitutes a human health concern. Past and present 

conditions of Vieques reflect the difficulties of approaching this type of human health assessment based 

on environmental data that was not necessarily developed to answer the type of questions associated 

with public health issues. In addition, Vieques social and environmental conditions are very complex. 

Thus, some degree of uncertainty will always remain. Nevertheless, military activities were always 

considered the major environmental and social stressor of Vieques’ residents. Some connections 

between military activities and human health concerns in Vieques have been established by local 

scientists and researchers and this report very well examines the scientific strengths and weaknesses of 

those connections. This report also incorporates new environmental, biomonitoring and health outcome 

data and revisits the previous ATSDR reports. Therefore, new recommendations and findings are 

integrated into this report. 

ATSDR Response: Thank you for your comments.

Has ATSDR adequately addressed the pathways of human exposure to bombing rangespecific contaminants?

Please include specific comments on:

Consumption of seafood from reefs near Vieques

[Comment] This subject was addressed adequately. ATSDR recognized the limitations of the data in 

measuring mercury levels in fish and shellfish. It also indicates that some children born to women who 

frequently ate fish from water surrounding Vieques were at increased risk of adverse health effect and 

some children who frequently ate the same fish were also at risk of harmful effects. Based on the 

information available, ATSDR could not make any connection with the military activities and the mercury 

level found in fish. Then, the best recommendation is to make a risk assessment around the LIA to 

determine the effect that military activities have had on the marine ecosystem. 

ATSDR Response: Thank you for your comments. The National Oceanic and Atmospheric 

Administration’s (NOAA) National Centers for Coastal Ocean Science (NCCOS), in 

consultation with NOAA’s Office of Response and Restoration (OR&R) and other local and 

regional experts, conducted a characterization of coral reef ecosystems, contaminants, and 

nutrient distribution patterns around Vieques (NOAA 2010).
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-74

Use of biomonitoring tools to assess exposure to metals and other hazardous chemicals in 

blood, urine, or hair that are related to historical bombing exercises

[Comment] This subject was addressed adequately in some extent. ATDSDR reviewed the PRDOH, and 

some local researcher studies, and found elevated levels of various metals in residents’ blood, urine and 

hair. ATSDR emphasized that the weakness of all these studies was the inability to investigate each 

person’s environment, thus making it impossible to identify the source for high metal concentration. 

The PRDOH identified cigarette use, hair dyes and seafood consumption as possible sources for high 

metal concentration. Dr. Ortiz Roque showed that some residents had elevated levels of mercury in hair 

and that the most likely source was fish consumption. The best recommendation to address this issue is 

to make a survey of Viequenses to determine the type and quantity of fish consumed as well as a 

biomonitoring study to measure mercury and other metals in blood and hair. ATSDR should use the 

preliminary data developed by PRDOH and Dr. Ortiz to enforce a more specific study, which include an 

association between residents’ habits, their environmental conditions and metal concentration in 

different parts of their body.

ATSDR Response: Thank you for your comment. We have recommended that a survey of 

Vieques residents be conducted to determine the types, frequency, and quantity of fish 

consumed. The results of this survey could be used to conduct additional risk assessments 

and statistical analyses to validate our concerns about mercury in Vieques reef fish.

Although ATSDR is not recommending a comprehensive, systematic biomonitoring effort at 

this time, public health officials could consider a limited and focused human biomonitoring 

investigation following the release of this report. If a biomonitoring investigation is 

conducted, it should include a comparison group from mainland Puerto Rico. If requested, 

CDC/ATSDR subject matter experts will provide technical assistance and support to PRDOH 

in planning and conducting such an investigation. Viequenses who remain concerned about 

exposure to mercury, cadmium, other metals, or metalloids should consult their healthcare

provider to discuss the need for and cost of testing. A qualified laboratory should do the 

testing and analysis. Consumption of food (produce, meat, dairy, eggs) grown on the island

[Comment] This subject was addressed adequately. The main ATSDR conclusion about this subject is 

that the overall data is insufficient to adequately determine human exposure or to draw any valid health 

conclusion. ATSDR evaluated Dr. Díaz and Dr. Massols (2003) research, which found cadmium levels in 

pigeon peas potentially harmful for preschool children. ATSDR cannot be certain of the extent to which 

military activities contribute to the cadmium level found in pigeon peas. Recommendations suggested 

by ATSDR encouraged additional sampling and collaborative data collection for plants, livestock and soil. 

Based on the data collected by Dr. Díaz and Dr. Massol, ATSDR should enforce more specific studies 

about this subject and its association with military activities. 

ATSDR Response: Thank you for your comment. In fulfilling its role as a nonregulatory 

science advisory agency, ATSDR cannot direct other entities to conduct further studies, nor 

collect samples of local produce. However, we hope that recommendations for a 
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-75

collaborative sampling effort will help resolve uncertainties and limitations in data on locally 

grown produce.

Exposure to air, soil, and water on Vieques

[Comment] This subject was addressed adequately to some extent. The main objective of this section 

was to determine whether airborne contaminant could potentially expose Viequenses in residential 

areas to harmful levels of metals and particulates that might result in adverse health effects. ATSDR 

used all the climate and meteorological information available as well as the ordinance detonation and 

the residential area air quality data. ATSDR reviewed and adapted a new version of a dispersion model 

and applied it to Vieques. Using this model ATSDR concluded that in residential areas of Vieques 

airborne from past military operations would have been essentially nondetectable and unlikely to have 

resulted in harmful effect. This conclusion is very critical in the sense that most of Vieques population 

receive the winds coming from the east (where the LIA was located) and they were not located far away 

from this military activities. This model should incorporate measurement of 2.5pm that is proved to be 

harmful for humans. This model should also include measurement of particulate matter coming from 

the Sahara desert, which is very well documented that affects human health throughout the Caribbean 

region. A conclusion sustaining that there is no air pollution reaching soil or water is somewhat 

uncertain. The rest of the data, conclusion and recommendations are very well documented.

ATSDR Response: Chapter 6, Section 6.2.2 of the summary document explicitly addressed 

the issue of PM2.5. No further revisions are necessary. The 2003 Air PHA evaluated the 

public health implications of exposure to airborne particulates from African Dust Storms 

(pages 59–61) and found that PM10 (and PM2.5) from such storms on Vieques were not at 

levels of health concern. But no contaminant-specific data on dust from African Dust Storms 

were available at the time of the Air PHA (which recommended further evaluation if such 

contaminant specific data became available). Contaminant-specific dust data are presented 

in a recent study by Gioda et.al. (2007) and a discussion of this information has been added 

to 6.2.3. 

Does the Vieques summary report adequately present and describe the limitations and 

uncertainty of assessing human exposure to bombing range-specific contaminants?

[Comment] Yes, the summary report, in general, adequately describes the limitations and uncertainties 

of assessing human exposure to military activities. As the report recognized, the data used has strengths 

and weaknesses and cannot address the effect of mixture and cumulative exposure on the health of 

Viequenses.

ATSDR Response: Thank you for your comment—no revision required.
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-76

Are independent studies utilized appropriately in the determination of potential health 

hazards?

[Comment] Yes, independent studies contained in this report are properly used to determine the 

potential health hazard caused to the population of Vieques by past military activities. Most of these 

studies bring out new information and data to support new evidence and conclusions. 

ATSDR Response: Thank you for your comment.

On the basis of ATSDR’s reevaluation of historical bombing activities in the Vieques 

summary report, has ATSDR reached the appropriate conclusions and recommendations?

[Comment] Based on the data and information available ATSDR, in general, reached appropriate 

conclusions and recommendations. As stated in the report, more studies could be done in order to 

complete the whole picture of a really complex environmental and human health problem. At this 

moment, the information collected represents a lot of fragmented pieces of an environmental health 

puzzle. Therefore, an integrated and holistic approach could be developed for future studies. 

ATSDR Response: ATSDR agrees and has made recommendations in the Report to 1) 

conduct a scientific survey of Viequenses to assess their seafood consumption and other 

food consumption, and 2) reanalyze the existing data using information obtained from the 

survey. Although ATSDR is not recommending a comprehensive, systematic biomonitoring 

effort at this time, public health officials could consider a limited and focused human 

biomonitoring investigation following the release of this report. ATSDR also recommends 

that Viequenses who remain concerned about exposure to mercury, cadmium, other 

metals, or metalloids should consult their healthcare provider to discuss the need for and 

cost of testing. 

Select the appropriate category below:

List recommended changes or reasons for not recommending)

o Recommend ( )

o Recommend with Required Changes (X)

o Not Recommended ( )

Additional Questions:

Are there any comments on ATSDR's peer review process?

[Comment] The peer review process is very well documented and guided. 

ATSDR Response: Thank you for your comment.

Are there any other comments?
An Evaluation of Environmental, Biological, and Health Data from the Island of Vieques 

(Public Comment) December 2011

Page | C-77

[Comment] Sometimes science is not sufficient to find answers to some environmental problems. 

Particularly, when dealing with the human health dimension of these problems. What is critical is to find 

the best possible response to the particular environmental health problem. In the case of Vieques, I 

think that a necessary approach is to develop a comprehensive epidemiological study of its population. 

This study should consider all human health conditions and diseases. It should also consider peoples’ 

habits, cultural activities and personal and social environmental conditions. This study should be 

complemented with several studies recommended in the different sections of this report. But, instead of 

approaching the problem from an environmental perspective, it will be better to approach the analysis 

from a human health dimension. I completely agree that a future comprehensive study should 

investigate the combined and cumulative effects of exposure to military activities in Vieques. 

ATSDR Response: ATSDR is mandated to focus on the environmental associations with 

adverse health effects. Also, it is not methodologically feasible to consider “all human health 

conditions and diseases.” Understanding these two facets, the agency’s approach is typically 

to identify environmental exposures of concern and then evaluate biologically plausible 

health effects possibly associated with these exposures.