August 31, 2007

Childhood adverse health outcomes and  drinking water exposures to 

chlorinated solvents at the U.S. Marine Corps Base Camp Lejeune, North 

CarolinaFrank J. Bove, Sc. D 

Agency for Toxic Substances and Disease Registry (ATSDR)Division of Health Studies

August 31, 2007

The findings and conclusions in this presentation have not been formally disseminated by the Agency for Toxic Substances and Disease Registry and should not be construed to represent any agency determination or policy.

August 31, 2007

ATSDR project teamPerri Ruckart

Principal InvestigatorFrank Bove

Senior ScientistShannon Rossiter

Study CoordinatorMorris Maslia

Research Env. Engineer, Water Modeling ActivitiesCarolyn Harris

Public Health Analyst

August 31, 2007

Outline

Site background

Previous epidemiological study at the base

Current case-control study 

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Site background

August 31, 2007

Site backgroundArea

~ 164 square milesPopulation:

~100,000 active duty and dependentsConsiderable in- and out-migration from base 

Estimated one-third of mothers receiving prenatal care at naval hospital during 1970s-80s were transferred before deliveryAverage duration in base housing is about 2 years

August 31, 2007

Base family housing areas and drinking water systems

10 base family housing areas 

3 water treatment plants (WTPs) serving base housing areas:Tarawa Terrace (TT - constructed in 1951/52)Holcomb Boulevard (HB - constructed in 1972)Hadnot Point (HP - constructed in the 1943) 

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Contamination of base drinking water supplies

Contamination of HP wells:Underground storage tanks containing degreasing solvents were installed near HP wells in 1940s-1950sSpills and dumping of benzene, toluene, ethyl benzene, xylenes

Contamination of TT wells:ABC One-Hour Cleaners began operation near the base in 1953Supply wells for TT installed 900 feet from septic tank of ABC One-Hour Cleaners in May 1951

August 31, 2007

Contamination of base drinking water supplies

Contamination of HP and TT drinking water systems was intermittent

Each system had more wells than necessary to supply water on any given dayWells rotated in and out of service

Contamination levels in drinking water distribution system depended on the wells being used at a particular time  

In each system, water from all wells in use was mixed before treatment and distribution 

August 31, 2007

Contamination of base drinking water supplies

Chlorinated solvents first detected in TT and HP wells in 1982 during routine sampling

Contamination of TT wells began in the late 1950sStart of contamination of HP wells is still being determined, but likely began by 1950 or earlier.

Highly contaminated wells at HP and TT were shut down in 1985

August 31, 2007

Maximum concentrations of chlorinated solvents in drinking water at the base, 1982-

1985 (tap water samples)

Hadnot PtTCE = 1,400 μg/L      (MCL = 5 μg/L)t-1,2-dichloroethane = 407 μg/L    (MCL = 70 μg/L)

Tarawa TerracePCE = 215 μg/L    (MCL = 5 μg/L)TCE = 8 μg/Lt-1,2-dichloroethane = 12 μg/L

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1997 ATSDR Public Health Assessment

Limited information in scientific literature on how chlorinated solvents in drinking water might affect a fetus or childRecommendation: Conduct epidemiological studies to evaluate

Whether maternal exposure was associated with a higher risk of having an adverse birth outcome (e.g., birth defects, low birth weight, preterm birth, fetal death) Whether maternal or infant (up to 1 year of life) exposure was associated with a childhood cancer (e.g., leukemia)

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Epidemiological studies at Camp Lejeune

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1998 ATSDR study on adverse pregnancy outcomes

Evaluated potential maternal exposure to drinking water contaminants on base and:  

Preterm birthSmall for gestational age (SGA) Mean birth weight deficit

Only used available databasesElectronic birth certificates available beginning in 196812,493 singleton live births on base during 1968-1985 Base family housing records linked to mother’s address at delivery and (in most instances) father’s nameStudy could not evaluate birth defects and childhood cancers

August 31, 2007

1998 ATSDR study on adverse pregnancy outcomes: results

Exposure to TT water (PCE): Elevated risk for SGA among infants born to:

mothers aged >35 yearsmothers with ≥2 prior fetal losses

Exposure to HP water (TCE):Elevated risk for SGA only among male infants

Exposure assessment error may have biased results towards the null

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Current ATSDR epidemiological study“Exposure to volatile organic compounds in drinking 

water and specific birth defects and childhood cancers”(case-control study)

Multi-step processReview scientific literature to identify specific birth defects and childhood cancers associated with drinking water contaminated with chlorinated solventsConduct telephone survey to ascertain potential casesObtain medical records to verify diagnoses of reported casesConduct a case-control study

interview parentsobtain estimates of exposure from the water modeling component

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Childhood adverse health outcomes from exposures to TCE in drinking water

Childhood leukemiaWoburn, Northern NJ study

Small for gestational ageWoburn, Camp Lejeune study

Fetal deathWoburn

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Childhood adverse health outcomes from exposures to TCE in drinking water

Birth defectsNeural tube defects (spina bifida, anencephaly)

Northern NJ study, (Woburn)

Oral clefts (cleft lip & cleft palate)Northern NJ study, (Woburn)

Major heart defectsTucson, AZ study

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Childhood adverse health outcomes from exposures to TCE in drinking water

Birth defects (continued)Choanal atresia (nasal defect)

Cluster in Woburn (3 observed, 0.15 expected)

Eye defectsWoburn

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Childhood adverse health outcomes from exposures to PCE in drinking water

Small for gestational age1998 Camp Lejeune study

Oral cleft defects (cleft lip & cleft palate)Northern NJ study

August 31, 2007

Current ATSDR epidemiological study: results of literature review

Based on the review of the scientific literature, the following outcomes were selected for further study

Neural tube defects (NTD)Oral cleft defects (cleft lip and cleft palate)Conotruncal heart defects

tetralogy of FallotD-transposition of the great arteriestruncus arteriosus pulmonary valve atresia with ventricular septal defectdouble outlet right ventricle

Choanal atresia (a nasal defect)Childhood leukemia Childhood non-Hodgkin’s lymphoma 

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Current ATSDR epidemiological study: telephone survey

Telephone survey was conducted to identify potential cases of the selected adverse childhood outcomes among births occurring during 1968-1985 to mothers residing on base any time during their pregnancy

Estimated number of births was between 16,000 and 17,000

Questions addressed by survey:Could a high percentage of the population be identified and contacted?Could most of the cases of these adverse outcomes in the population be reliably ascertained and verified?Would there be sufficient numbers of cases to study?

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Current ATSDR epidemiological study: results of telephone survey

Parents of 12,598 eligible children were surveyedOverall participation rate of  74%-80%

Sufficient numbers of NTDs, oral clefts, and childhood cancers reported 

106 reported cases: 35 NTDs42 oral cleft defects 29 childhood hematopoietic cancers

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Current ATSDR epidemiological study: verification of cases

Verification of diagnoses of cases ascertained by survey has been completedConfirmed cases (N=57):

17 NTD24 clefts16 hematopoietic cancers

32 confirmed not to have the reported diseases7 refused to participate7 could not be verified (no medical records)3 were ineligible

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Current ATSDR epidemiological study: case/control recruitment

Parents of 54 cases were interviewed52 mothers interviewed

45 mothers and fathers interviewed7 mothers only interviewed

2 fathers only interviewed

Parents of 3 cases could not be located or contacted

Parents of 7 potential cases refused to participate in the verification process and interviews

Participation rate: 54/64 = 84.4%

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Current ATSDR epidemiological study: case/control recruitment

816 controls randomly sampled from the survey population to obtain ~10:1 ratio of controls to cases

Efforts were made to contact 651 of the 816 controlsParents of 548 controls were interviewed 

461 mothers interviewed359 mothers and fathers interviewed102 mothers only interviewed

87 fathers interviewed onlyParents of 103 controls refused or could not be contacted

Participation rate: 548/651 = 84.2%

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Current ATSDR epidemiological study: parent interviews

Interviews were conducted in Spring-Summer 2005 to parents of cases and controls to obtain information on:

Maternal water consumption habits Maternal residential historyMaternal exposures during pregnancy

Occupation, medications, illnesses, smoking, passive smoke, hobbies, (etc.) 

Parental risk factorsOccupational history, service in Vietnam, (etc.)

August 31, 2007

Current ATSDR epidemiological study: water modeling component

Lack of historical, contaminant-specific data at Camp Lejeune requires a modeling approach 

Modeling of groundwater flow and water distribution system Historical reconstruction to provide a quantitative estimate of exposureSimilar to (but more complex than) the approach taken in Dover Township, NJ Childhood Cancers Study

- Childhood adverse health outcomes and  drinking water exposures to chlorinated solvents at the U.S. Marine Corps Base Camp Lej
- ATSDR project team
- Outline
- Site background
- Site background
- Base family housing areas and drinking water systems
- Contamination of base drinking water supplies
- Contamination of base drinking water supplies
- Contamination of base drinking water supplies
- Maximum concentrations of chlorinated solvents in drinking water at the base, 1982-1985 (tap water samples)
- 1997 ATSDR Public Health Assessment
- Epidemiological studies at Camp Lejeune
- 1998 ATSDR study on adverse pregnancy outcomes 
- 1998 ATSDR study on adverse pregnancy outcomes: results
- Current ATSDR epidemiological study�“Exposure to volatile organic compounds in drinking water and specific birth defects and c
- Childhood adverse health outcomes from exposures to TCE in drinking water
- Childhood adverse health outcomes from exposures to TCE in drinking water
- Childhood adverse health outcomes from exposures to TCE in drinking water
- Childhood adverse health outcomes from exposures to PCE in drinking water
- Current ATSDR epidemiological study: results of literature review
- Current ATSDR epidemiological study: telephone survey
- Current ATSDR epidemiological study: results of telephone survey
- Current ATSDR epidemiological study: verification of cases
- Current ATSDR epidemiological study: case/control recruitment
- Current ATSDR epidemiological study: case/control recruitment
- Current ATSDR epidemiological study: parent interviews