The National Study of 

Chemical Residues in Lake Fish Tissue

U.S. Environmental Protection Agency

Office of Water

Office of Science and Technology

September 2009
Notice

This report was prepared by the U.S. Environmental Protection Agency (EPA), Office 

of Water, Office of Science and Technology. It has been subjected to the Agency’s peer 

review and administrative review processes. The EPA Project Manager for preparation of 

this document was Leanne Stahl who provided overall project coordination and technical 

direction. Tetra Tech, Inc. provided primary support for the development of this document 

under Contract Numbers EP-C-04-030 and EP-C-09-019. Blaine Snyder was the Tetra Tech 

Project Manager. Additional support was provided by Computer Sciences Corporation under 

Contract Number ET-W-06-046.

The U.S. Environmental Protection Agency, Office of Water, Office of Science and 

Technology has approved this report for publication. Mention of trade names, commercial 

products, or services does not constitute official EPA approval, endorsement, or 

recommendation for use.

The appropriate citation for this document is:

U.S. Environmental Protection Agency (USEPA).  2009.  The National Study of 

Chemical Residues in Lake Fish Tissue.  EPA-823-R-09-006. 

U.S. Environmental Protection Agency, Office of Water, Washington, DC.

This document (including appendices) can be downloaded from the following 

EPA Office of Water website: 

www.epa.gov/waterscience/fishstudy/

Cover and report photo credits:

Blaine D. Snyder, Tetra Tech, Inc., Owings Mills, MD
The National Study of Chemical Residues in Lake Fish Tissue

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Table of Contents

Acknowledgements ........................................................................................................................... v

List of Acronyms and Abbreviations................................................................................................ ix

Executive Summary ......................................................................................................................... xi

1.0 Introduction.............................................................................................................................. 1

1.1 Program History and Development .................................................................................. 1

1.2 Study Objective ................................................................................................................ 2

2.0 Study Design and Approach...................................................................................................... 3

2.1 Background...................................................................................................................... 3

2.2 Study Design Development............................................................................................... 3

2.2.1 Study Design Workshop...................................................................................... 3

2.2.2 Statistical Selection of Lakes............................................................................... 4

2.2.3 Target Chemical Selection................................................................................... 6

2.3 Mobilization..................................................................................................................... 9

2.3.1 Orientation and Training Workshops ................................................................. 9

2.3.2 Partnerships...................................................................................................... 10

2.3.3 Lake Evaluations.............................................................................................. 11

2.3.4 Quality Assurance and Field Sampling Plans.................................................... 11

2.4 Sample Collection........................................................................................................... 12

2.4.1 Sampling Locations .......................................................................................... 12

2.4.2 Target Species.................................................................................................... 13

2.4.3 Composite Samples........................................................................................... 14

2.4.4 Sampling Methods ............................................................................................ 14

2.4.5 Sample Collection Quality Assurance/Quality Control (QA/QC).................... 15

2.5 Sample Analysis.............................................................................................................. 16

2.5.1 Non-routine Samples........................................................................................ 16

2.5.2 Sample Preparation ........................................................................................... 16

2.5.3 Laboratory Network......................................................................................... 17

2.5.4 Analytical Methods........................................................................................... 17

2.5.5 Sample Analysis QA/QC .................................................................................. 18

2.6 Statistical Analysis of Study Data ................................................................................... 18

2.6.1 Calculating the Sample Weights........................................................................ 19

2.6.2 Estimating the Size of the Target Population of Lakes...................................... 20

2.6.3 Estimating the Size of the Sampled Population of Lakes................................... 20

2.6.4 Estimating Fish Tissue Concentrations............................................................. 20

2.6.5 Statistical Analysis QA/QC .............................................................................. 21

3.0 Results .................................................................................................................................... 23

3.1 Technical Elements......................................................................................................... 25

3.1.1 Reporting Units ................................................................................................ 25

3.1.2 Detection and Quantitation Limits .................................................................. 25

3.1.3 Total Toxicity Equivalency and Summed Chemicals ........................................ 26

3.1.4 Cumulative Distribution Functions .................................................................. 27

3.1.5 Human Health Screening Values....................................................................... 27
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3.2 Chemicals Not Detected................................................................................................. 29

3.3 Rarely-detected Chemicals ............................................................................................. 30

3.4 Commonly-detected Chemicals...................................................................................... 33

3.4.1 Mercury ............................................................................................................ 33

3.4.2 Total Polychlorinated Biphenyls (PCBs) ........................................................... 38

3.4.3 Total Dioxins and Furans ................................................................................. 43

3.4.4 Total DDT ........................................................................................................ 49

3.4.5 Total Chlordane ................................................................................................ 54

 3.5 Sampling Variability....................................................................................................... 59

4.0 Conclusions and Recommendations........................................................................................ 61

4.1 Chemical Occurrences.................................................................................................... 61

4.1.1 Mercury ............................................................................................................ 61

4.1.2 PCBs................................................................................................................. 61

4.1.3 Dioxins and Furans........................................................................................... 62

4.1.4 DDT and Chlordane......................................................................................... 62

4.2 Lessons Learned............................................................................................................. 63

4.2.1 Importance of Partnerships............................................................................... 63

4.2.2 Adequate Time for Planning and Mobilizing .................................................... 64

4.2.3 Commitment to Rigorous QA/QC ................................................................... 64

4.3 Data Availability ............................................................................................................ 64

4.4 Future Monitoring.......................................................................................................... 65

5.0 References............................................................................................................................... 67

Appendix A. National Lake Fish Tissue Study Sampling Locations

Appendix B. Target Chemicals

Appendix C. Target Species

Appendix D. Analytical Methods

Appendix E. Percentile Tables for Detected Target Chemicals

Appendix F. Occurrence of Target Chemicals

Appendix G. Cumulative Distribution Functions

Appendix H. Detection Agreement between Replicate Sample Pairs

Appendix I. Tissue Concentration Differences between Replicate Sample Pairs
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Figures

Figure 1. Locations of 10 regional orientation and training workshops.......................................... 9

Figure 2. National Lake Fish Tissue Study participants................................................................ 10

Figure 3. National Lake Fish Tissue Study sampling locations (500 lakes).................................... 12

Figure 4. Box-and-whisker plot of mercury concentrations in predator and

bottom-dweller samples................................................................................................. 35

Figure 5. Cumulative distribution function of mercury concentrations in predator samples......... 36

Figure 6. Cumulative distribution function of mercury concentrations in

bottom-dweller samples................................................................................................. 37

Figure 7. Box-and-whisker plot of PCB (sum of congeners) concentrations in predator

and bottom-dweller samples .......................................................................................... 40

Figure 8. Cumulative distribution function of total PCB concentrations in predator samples....... 41

Figure 9. Cumulative distribution function of total PCB concentrations in

bottom-dweller samples................................................................................................. 42

Figure 10. Box-and-whisker plot of total dioxin and furan concentrations in predator

and bottom-dweller samples .......................................................................................... 46

Figure 11. Cumulative distribution function of total dioxin and furan concentrations

in predator samples........................................................................................................ 47

Figure 12. Cumulative distribution function of total dioxin and furan concentrations

in bottom-dweller samples............................................................................................. 48

Figure 13. Box-and-whisker plot of total DDT concentrations in predator and

bottom-dweller samples................................................................................................. 51

Figure 14. Cumulative distribution function of total DDT concentrations in predator samples...... 52

Figure 15. Cumulative distribution function of total DDT concentrations in

bottom-dweller samples................................................................................................. 53

Figure 16. Box-and-whisker plot of total chlordane concentrations in predator

 and bottom-dweller samples ......................................................................................... 56

Figure 17. Cumulative distribution function of total chlordane concentrations in 

predator samples............................................................................................................ 57

Figure 18. Cumulative distribution function of total chlordane concentrations in

bottom-dweller samples................................................................................................. 58
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Tables

Table 1. Numbers of Lakes by Size Category in the Sample Frame (from RF3) ............................. 5

Table 2. Number of Lakes Selected for Potential Sampling by Size Category and Year ...................5

Table 3. Number of Reserve Lakes Selected for Potential Sampling by Size Category and Year .... 5

Table 4. Target Chemicals and Analytical Methods for the National Lake Fish Tissue Study ....... 7

Table 5. Recommended Target Species for Lakes and Reservoirs (in Order of Preference) .......... 13

Table 6. Estimated Number of Lakes by Evaluation Status, Lake Size Category, and

Composite Type ............................................................................................................. 24

Table 7. Reporting Units for EPA Standard Analytical Methods................................................. 25

Table 8. Human Health Screening Values (SV) for Interpreting National Lake Fish Tissue

Study Predator Results................................................................................................... 28

Table 9. Chemicals Not Detected in Any Samples ....................................................................... 29

Table 10. Infrequent Chemical Occurrences in Predators (Fillets) ................................................. 31

Table 11. Infrequent Chemical Occurrences in Bottom Dwellers (Whole Bodies) ......................... 32

Table 12. Percentiles for Mercury Concentrations in Predator Samples......................................... 34

Table 13. Percentiles for Mercury Concentrations in Bottom-dweller Samples.............................. 34

Table 14. Percentiles for PCB Concentrations in Predator Samples ............................................... 39

Table 15. Percentiles for PCB Concentrations in Bottom-dweller Samples .................................... 40

Table 16. Percentiles for Dioxin and Furan Concentrations (D/F TEQ) in Predator Samples........ 45

Table 17. Percentiles for Dioxin and Furan Concentrations (D/F TEQ) in Bottom-dweller

Samples.......................................................................................................................... 45

Table 18. Percentiles for Dioxin, Furan, and Coplanar PCB Concentrations (Total TEQ)

in Predator Samples ....................................................................................................... 45

Table 19. Percentiles for Dioxin, Furan, and Coplanar PCB Concentrations (Total TEQ)

in Bottom-dweller Samples ............................................................................................ 46

Table 20. Percentiles for Total DDT Concentrations in Predator Samples..................................... 50

Table 21. Percentiles for Total DDT Concentrations in Bottom-dweller Samples.......................... 50

Table 22. Percentiles for Total Chlordane Concentrations in Predator Samples ............................ 55

Table 23. Percentiles for Total Chlordane Concentrations in Bottom-dweller Samples ................. 55
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Acknowledgements

This report is the culmination of nine years of collaboration between the U.S. Environmental Protection Agency (EPA) and a national network of 58 state, tribal, and federal agencies to plan and 

conduct the National Study of Chemical Residues in Lake Fish Tissue (or National Lake Fish Tissue 

Study). EPA’s Office of Water (OW) managed the study and coordinated the efforts of participating agencies, and EPA’s Office of Research and Development (ORD) provided technical support for 

study design development and statistical analysis of the data. Within OW, Leanne Stahl has served 

as the National Lake Fish Tissue Study Manager for ten years, and Jane Farris led the initial year of 

study planning. They were supported by the National Lake Fish Tissue Study Management Team, 

consisting of the following EPA and contractor staff: Tony Olsen (EPA/ORD); Cindy Simbanin, 

Henry Kahn, and Marla Smith (EPA/OW); Blaine Snyder, Jennifer Pitt, and Amanda Richardson 

(Tetra Tech, Inc.); and Lynn Walters, Michael Walsh, Neal Jannelle, and Erin Salo (Computer Sciences Corporation).

The following EPA Regional Fish Study Coordinators played key roles in organizing study logistics 

and conducting lake reconnaissance and field sampling: Peter Nolan and Hilary Snook (Region 1); 

James Kurtenbach (Region 2); Frank Borsuk and Charles Kanetsky (Region 3); Alan Auwater and 

Lonnie Dorn (Region 4); Pete Redmon and Holly Arrigoni (Region 5); Philip Crocker (Region 6); 

Lorenzo Sena (Region 7); Toney Ott (Region 8); Peter Husby (Region 9); and Lillian Herger and 

Kellie Kubena (Region 10).

EPA’s Office of Water would like to express appreciation to all of the staff in the participating agencies who conducted lake reconnaissance, planned sampling logistics, and collected fish samples. 

Their combined efforts were crucial to the success of this study. The following agencies made longterm, voluntary commitments to support the National Lake Fish Tissue Study:

Alabama Department of Environmental Management

Arizona Game and Fish Department

Arkansas Department of Environmental Quality

California Department of Fish and Game

Colorado Division of Wildlife

Connecticut Department of Environmental Protection

Crater Lake National Park

Florida Fish and Wildlife Conservation Commission

Georgia Department of Natural Resources

Idaho Department of Environmental Quality

Illinois Environmental Protection Agency

Illinois Department of Natural Resources

Indiana Department of Environmental Management

Iowa Department of Natural Resources

Kansas Department of Health and Environment

Kentucky Department of Environmental Protection
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The National Study of Chemical Residues in Lake Fish Tissue

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Louisiana Department of Environmental Quality

Maine Department of Environmental Protection

Maryland Department of the Environment

Maryland Department of Natural Resources

Massachusetts Department of Environmental Protection

Michigan Department of Environmental Quality

Minnesota Chippewa Tribe

Minnesota Department of Natural Resources

Mississippi Department of Environmental Quality

Missouri Department of Conservation

Missouri Department of Natural Resources

Montana Department of Fish, Wildlife and Parks

Nebraska Department of Environmental Quality

Nevada Division of Wildlife

New Hampshire Department of Environmental Services

New Jersey Department of Environmental Protection

New Mexico Environment Department

New York Department of Environmental Conservation

North Carolina Department of Environment and Natural Resources

North Dakota Department of Health

Ohio Department of Natural Resources

Oklahoma Conservation Commission

Oklahoma Department of Environmental Quality

Oregon Department of Environmental Quality

Pennsylvania Department of Environmental Protection

Pictured Rocks National Lakeshore

Pyramid Lake Paiute Tribe

Rhode Island Department of Environmental Management

South Carolina Department of Health and Environmental Control

South Dakota Game, Fish, and Parks

Tennessee Valley Authority

Tennessee Wildlife Resources Agency

Texas Commission on Environmental Quality

Utah Department of Environmental Quality

Vermont Department of Environmental Conservation

Virginia Department of Environmental Quality

Washington Department of Ecology

West Virginia Department of Environmental Protection

Wind River Environmental Quality Commission

Wisconsin Department of Natural Resources

Wyoming Game and Fish Department

Yellowstone National Park
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The principal authors of this report are Leanne Stahl (EPA/OW), Tony Olsen (EPA/ORD), Blaine 

Snyder (Tetra Tech, Inc.) and Jennifer Pitt (Tetra Tech, Inc.). Tony Olsen kindly agreed to lead the 

statistical analysis of the data for the report. Computer Sciences Corporation developed the fish 

study database and prepared data files for statistical analysis. Tetra Tech formatted the statistical 

analysis results, integrated text and graphics developed by the authors, and provided support for 

final production of the report. External peer review of the report was conducted by Dr. Robert C. 

Hale of the Virginia Institute of Marine Science (VIMS), Dr. Charles Jagoe of the Savannah River 

Ecology Laboratory, and Dr. N. Scott Urquhart of the Colorado State University (Emeritus).
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List of Acronyms and Abbreviations

ATSDR Agency for Toxic Substances and Disease Registry

BHC benzene hexachloride

CAS Chemical Abstracts Service

CD compact disc

CDF cumulative distribution function

CEC containment of emerging concern

CFR Code of Federal Regulations

COC chain of custody

DDD dichlorodiphenyldichloroethane

DDE dichlorodiphenyldichloroethylene

DDT dichlorodiphenyltrichloroethane

DMA dimethylarsinic acid 

EMAP Environmental Monitoring and Assessment Program

EPA Environmental Protection Agency (U.S.)

FDA Food and Drug Administration

GC/FPD gas chromatography/flame photometric detector

GC/HSD gas chromatography/halide specific detector

GC/MS gas chromatography/mass spectrometry

GIS geographic information system

HpCB heptachlorobiphenyl

HpCDD heptachlorodibenzodioxin

HpCDF heptachlorodibenzofuran

HxCB hexachlorobiphenyl

HxCDD hexachlorodibenzodioxin

HxCDF hexachlorodibenzofuran

IRIS Integrated Risk Information System

MDL method detection limit

ML minimum level

MMA monomethylarsonic acid

NOAA National Oceanic and Atmospheric Administration

OCDD octachlorodibenzodioxin

OCDF octachlorodibenzofuran
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Acronyms and Abbreviations

OPPTS Office of Pesticides, Prevention, and Toxic Substances

ORD Office of Research and Development

OST Office of Science and Technology

OW Office of Water

PAH polycyclic aromatic hydrocarbon

PBT persistent, bioaccumulative, and toxic

PCB polychlorinated biphenyl

PeCB pentachlorobiphenyl

PeCDD pentachlorodibenzodioxin

PeCDF pentachlorodibenzofuran

QA/QC quality assurance/quality control

QAPP quality assurance project plan

RF3 River Reach File Version 3

SCC sample control center

SOP standard operating procedure

SV screening value

TeCB tetrachlorobiphenyl

TEF toxicity equivalency factor

TEQ toxic equivalency concentration

TCDD tetrachlorodibenzodioxin

TCDF tetrachlorodibenzofuran

USEPA United States Environmental Protection Agency

WQC water quality criterion
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Executive Summary

Environmental monitoring provides crucial data for describing the condition of the 

environment and for assessing the effectiveness of pollution control activities. In the 1990s, 

EPA identified a lack of information necessary to accurately characterize the condition of 

the Nation’s surface waters and responded by designing a series of statistically-based surveys 

to produce information on the condition of lakes, streams, rivers, and coastal waters in the 

United States. The National Study of Chemical Residues in Lake Fish Tissue (or National 

Lake Fish Tissue Study) is one of the statistically-based surveys conducted by EPA since the 

late 1990s. This study is a national screening-level survey of chemical residues in fish tissue 

from lakes and reservoirs in the conterminous United States (lower 48 states), excluding 

the Laurentian Great Lakes and Great Salt Lake. It is unique among earlier fish monitoring 

efforts in the United States because the sampling sites were selected according to a statistical 

(random) design. Study results allow EPA to estimate the percentage of lakes and reservoirs 

in the United States with chemical concentrations in fish tissue that are above levels of 

potential concern for humans or for wildlife that eat fish. This survey also includes the 

largest set of chemicals ever studied in fish. Whole fish and fillets were analyzed for 268 

persistent, bioaccumulative, and toxic (PBT) chemicals, including mercury, arsenic, dioxins 

and furans, the full complement of polychlorinated biphenyl (PCB) congeners, and a large 

number of pesticides and semivolatile organic compounds.

Partnerships made this study possible. Prior to beginning field sampling for the study, EPA 

built a national network of partners that included 47 states, three tribes, and two other 

federal agencies. Fisheries staff from more than 50 agencies worked for nearly five years 

to evaluate the suitability 

of lakes for sampling 

and to collect fish for the 

study. This study provides 

an excellent example of 

state, federal, and tribal 

collaboration. Participating 

agencies made a critical 

contribution to the success 

of this study through their 

voluntary commitments and 

dedicated efforts. 

Fire Lake, Michigan - (Target Lake Number 0309)
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Executive Summary

Study Objective

The objective of the National Lake Fish Tissue Study is to estimate the national distribution 

of selected persistent, bioaccumulative, and toxic (PBT) chemical residues in fish tissue from 

lakes and reservoirs of the conterminous United States. Results from this study provided 

EPA with the first opportunity to:

n Develop national estimates of the median concentrations of PBT chemicals in lake fish;

n Estimate the percentage of lakes and reservoirs with fish tissue concentrations above 

specified thresholds related to human health; and 

n Define national baseline information for tracking changes in concentrations of PBT 

chemicals in freshwater fish as a result of the combined effects of pollution control 

activities and natural degradation.

Study Design and Approach

The National Lake Fish Tissue Study focused on lakes and reservoirs (hereafter referred to 

collectively as lakes) for two reasons: they occur in a variety of landscapes where they can 

receive and accumulate contaminants from several sources (including direct discharges into 

water, air deposition, and agricultural or urban runoff) and there is usually limited dilution 

of contaminants compared to flowing streams and rivers. Monitoring fish for chemical 

contamination in lakes is also important because these areas are frequently used for sport 

fishing. According to EPA’s National Listing of Fish Advisories, 43% of the Nation’s lake 

acres are under fish consumption advisories.

This study applied a statistical or probability-based sampling approach so that results could 

be used to describe fish tissue contaminant concentrations in lakes on a national basis. The 

Nation’s lakes were divided into six size categories based on surface area. Assigning different 

probabilities to each category prevented small lakes from dominating the group of lakes 

selected for sampling. It also allowed a similar number of lakes to be selected in each size 

category.

For this study, a lake is defined as a permanent body of water with a permanent fish 

population that has a surface area of at least one hectare (2.47 acres), a depth of at least 

one meter (3.28 feet), and at least 1,000 square meters of open, unvegetated water. The 

lower 48 states contain an estimated 147,000 lakes meeting these criteria (i.e., the target 

population). A list of candidate lakes was randomly selected from the target population for 

this study. From this list, EPA identified 500 sites that were accessible and appropriate for 

fish collection.

The target population consists of all lakes in the lower 48 states that met the study definition of a lake (147,000 lakes). The sampled population consists of all target lakes that were 

accessible for fish collection. Under ideal circumstances, the target and sampled populations 
The National Study of Chemical Residues in Lake Fish Tissue

Executive Summary

xiii

should coincide. However, for this study, the sampled population is a subset of the target 

population. A large number of target lakes were not accessible to field sampling teams 

because the lakes were either located in remote wilderness areas or on private property 

where landowners denied EPA permission to sample them. There is a different sampled 

population for each composite type based on differences in the occurrence of predators and 

bottom dwellers at the 500 sampling locations. The sampled population for predators is an 

estimated 76,559 lakes, and the sampled population for bottom dwellers is an estimated 

46,190 lakes. All predator and bottom-dweller results presented in this report apply to these 

sampled populations of lakes.

Target Chemical Selection

The National Lake Fish Tissue Study includes the largest number of chemicals ever studied 

in fish. EPA developed the list of target chemicals for this study from the agency’s multimedia list of 451 PBT chemicals, along with a list of 130 chemicals referenced in several contemporary fish tissue and bioaccumulation studies. EPA selected chemicals that had detailed 

information available, were known to accumulate, and were identified as important in one 

or more EPA programs. The final list contains 268 chemicals, including mercury, five forms 

of arsenic, 17 dioxins and furans, 159 PCB congener measurements, 46 pesticides, and 40 

semivolatile organic compounds. 

National Lake Fish Tissue Study Sampling Sites (500 lakes)
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Executive Summary

Sample Collection

EPA planned four years of field sampling for the 

National Lake Fish Tissue Study. After a brief pilot 

in the fall of 1999 to test sampling logistics, EPA 

and its partners began full-scale fish sampling in 

2000 and continued sampling annually through 

2003. Each year of the study, field sampling 

teams collected fish from about 125 different 

lakes distributed across the lower 48 states. These 

teams applied consistent methods nationwide to 

collect composite samples of a predator fish species 

(e.g., bass or trout) and a bottom-dwelling species 

(e.g., carp or catfish) from each lake or reservoir. 

EPA identified twelve target predator species and 

six target bottom-dwelling species to limit the 

number of species included in the study. Predator 

and bottom-dweller composites each consisted of 

five adult fish of the same species and similar size (i.e., the smallest individual in a composite 

was no less than 75% of the total length of the largest individual). Field teams re-sampled 

more than 10% of the lakes to allow EPA to evaluate any possible sampling variability.

Sample Analysis

EPA analyzed different tissue fractions for predator 

composites (fillets) and bottom-dweller composites 

(whole bodies) to obtain chemical residue data 

for the 268 target chemicals. Analyzing fish fillets 

provides information for human health, while 

whole-body analysis produces information for 

ecosystem health. A single laboratory prepared all 

fish samples in a strictly-controlled, contaminationfree environment. This laboratory distributed fish 

tissue samples to four laboratories that specialize in 

analysis of metals, pesticides, semivolatile organic 

chemicals, and PCBs, dioxins, and furans. To 

minimize variability among sample results, EPA 

used the same laboratory for each type of analysis, 

and these laboratories applied the same analytical 

method for each chemical for the duration of the 

study. Resulting fish tissue concentrations were 

reported on a wet weight basis. 

Sampling at Norvell Lake, Michigan 

– (Target Lake Number 0664)

Analytical Chemistry Laboratory 

Clean Room
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xv

Statistical Analysis

The data analyzed for the National Lake Fish Tissue Study include tissue concentrations for 

each target chemical (e.g., mercury) or chemical group (e.g., PCBs) and fish composite type 

(i.e., predator and bottom-dweller composites). Analysis of the fish tissue data incorporated 

elements of the survey design, along with information from the field sampling operations 

and laboratory analyses. Statistical analysis included evaluating information to determine 

the status of each lake, adjusting the sample weights based on the lake status, estimating the 

number and proportion of lakes in the sampled population, and estimating the cumulative 

distribution and percentile concentrations of the target chemicals in fillets for predators and 

whole bodies for bottom dwellers.

Results

The National Lake Fish Tissue Study 

is the first national assessment of 

freshwater fish contamination in the 

United States for which sampling sites 

were selected according to a statistical 

(random) design. To interpret the 

results, it is essential to understand the 

following important points about this 

design:

n During the four-year sampling 

period, field teams collected 

486 predator composites and 

395 bottom-dweller composites 

from the 500 sampling locations. 

Predator and bottom-dweller 

species did not occur together 

at every sampling site; however, 

if either a predator or bottomdweller species was present, the 

target lake was sampled.

n The 486 predator composites 

and the 395 bottom-dweller 

composites collected during the study each comprise nationally-representative samples 

for the lower 48 states whose results can be extrapolated to an estimated 76,559 lakes 

for predators and an estimated 46,190 lakes for bottom-dwellers.

n The unequal probability design makes it necessary to apply sample weights (derived 

from the various probabilities assigned to each of the lake size categories) to the fish 

tissue data to develop national estimates of fillet (predator) and whole-body (bottomdweller) fish tissue concentrations for each of the 268 target chemicals.

Lake 79, Wyoming – (Target Lake Number 0052)
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Executive Summary

Results from the National Lake Fish Tissue Study indicate that mercury, PCBs, and dioxins 

and furans are widely distributed in lakes and reservoirs in the lower 48 states. Mercury and 

PCBs were detected in all the fish samples collected from the 500 sampling sites. Dioxins 

and furans were detected in 81% of the predator samples (fillet composites) and 99% of the 

bottom-dweller samples (whole-fish composites). In contrast, there were a number of chemicals that were not detected in any of the fish samples collected during the study. Forty-three 

of the 268 target chemicals were not detected in any samples, including all nine organophosphate pesticides (e.g., chlorpyriphos and diazinon), one PCB congener (PCB-161), and 16 of 

the 17 polycyclic aromatic hydrocarbons (PAHs) analyzed as semivolatile organic chemicals. 

There were also seventeen other semivolatile organic chemicals that were not detected.

In reporting the analytical results for this study, it is important to distinguish between 

detection and presence of a chemical in a fish tissue sample. Estimates of fish tissue 

concentrations ranging from the method detection limit (MDL) to the minimum level of 

quantitation (ML) are reported as being present with a 99% level of confidence. However, 

if a chemical is reported as “not detected” at the MDL level, there is a 50% possibility that 

the chemical may be present. Therefore, results for chemicals not detected in the fish tissue 

samples are reported as less than the MDL rather than zero. In interpreting the results, it is 

also important to know the MDL for each chemical (Appendix B).

According to EPA’s 2008 Biennial National Listing of Fish Advisories, mercury, PCBs, 

dioxins and furans, DDT, and chlordane accounted for 97% of the advisories in effect 

at the end of 2008. These five chemicals were also commonly detected in fish samples 

collected for the National Lake Fish Tissue Study. Since human health screening values 

(SVs) were readily available, they were applied to total concentrations of mercury, PCBs, 

Snowbank Lake, Minnesota – (Target Lake Number 0235)
The National Study of Chemical Residues in Lake Fish Tissue

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xvii

dioxins and furans, DDT, and chlordane found in 

predator fillets. The mercury SV is the tissue-based 

water quality criterion published by EPA in 2001. 

All other SVs are risk-based consumption limits 

published in 2000 in EPA’s Guidance for Assessing 

Chemical Contaminant Data for Use in Fish 

Consumption Limits, Third Edition. Specifically, 

the applied SVs are the upper limit of the four-mealper-month concentration range for the conservative 

consumption limit (where tissue concentrations 

are available for both cancer and noncancer health 

endpoints). If available, wildlife criteria could be 

applied in the same manner to interpret the wholebody data from analysis of bottom-dweller samples.

Predator results for the five commonly-detected 

chemicals indicate that:

n 48.8% of the sampled population of lakes had 

mercury tissue concentrations that exceeded the 

300 ppb (0.3 ppm) human health SV for mercury, 

which represents a total of 36,422 lakes.

n 16.8% of the sampled population of lakes had 

total PCB tissue concentrations that exceeded 

the 12 ppb human health SV, which represents a 

total of 12,886 lakes.

n 7.6% of the sampled population of lakes had 

dioxin and furan tissue concentrations that 

exceeded the 0.15 ppt [toxic equivalency or 

TEQ] human health SV, which represents a total 

of 5,856 lakes.

n 1.7% of the sampled population of lakes had 

DDT tissue concentrations that exceeded the 

69 ppb human health SV, which represents a 

total of 1,329 lakes.

n 0.3% of the sampled population of lakes had 

fish tissue concentrations that exceeded the 

67 ppb human health SV for chlordane, which 

represents a total of 235 lakes.

This report provides national baseline information 

to track changes in PBT chemical concentrations 

in freshwater fish resulting from pollution control 
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Executive Summary

activities and chemical degradation. The results of the National Lake Fish Tissue Study are 

presented to inform the public, water quality specialists, natural resource managers, and 

government officials of the distribution and prevalence of selected PBT chemicals in fish 

tissue from lakes and reservoirs of the conterminous United States. The findings should also 

be useful to aid in the design and focus of future fish tissue contaminant studies. National 

Lake Fish Tissue Study sampling design information and results have also been published 

in peer-reviewed journal articles by Olsen et al. (2009) and Stahl et al. (2009). Additional 

information, including instructions for obtaining study data and links to related study 

literature, is posted on the Internet at http://www.epa.gov/waterscience/fishstudy/.
1

The National Study of Chemical Residues in Lake Fish Tissue

1.0 Introduction

1.1 Program History and Development

The U.S. Environmental Protection Agency’s (EPA’s) Office of Science and Technology (OST) 

within the Office of Water (OW) conducted a national screening-level study of contamination in freshwater fish tissue called the National Study of Chemical Residues in Lake Fish 

Tissue (or National Lake Fish Tissue Study). This study was a priority activity sponsored 

under the agency-wide Persistent, Bioaccumulative, and Toxic (PBT) Chemical Program. 

PBT pollutants are highly toxic, long-lasting chemicals that can build up in the food chain 

to levels that are harmful to human and ecosystem health. In 1998, EPA developed the Multimedia Strategy for Priority Persistent, Bioaccumulative, and Toxic (PBT) Pollutants. The 

purpose of this multimedia strategy was to identify actions to address risks posed by PBT 

chemicals in the environment. One of the priority actions in the strategy was to evaluate the 

occurrence of PBT chemicals in fish from U.S. waters. In response to the strategy, the Office 

of Water committed to conducting a comprehensive study of PBT chemical contamination in 

fish tissue as an indication of the extent of this contamination in the Nation’s waters. 

At the time of this commitment, OW recognized that there were critical national data gaps 

that prevented EPA from characterizing the condition of the nation’s surface waters. Based 

on earlier environmental assessment work conducted by the Environmental Monitoring 

and Assessment Program (EMAP) in EPA’s Office of Research and Development (ORD), 

OW determined that probabilistic (random) surveys would be appropriate to address these 

national data gaps. The National Lake Fish Tissue Study is one in a series of five probabilistic surveys undertaken by EPA since the late 1990s to provide statistically-based data to 

characterize the national condition of lakes, streams, rivers, and coastal waters.a

 OW has 

partnered with ORD to design and implement these surveys.

Planning for the National Lake Fish Tissue Study began in the fall of 1998. In October 

1998, EPA convened a two-day workshop of more than 50 scientists from state, federal, and 

tribal agencies to obtain technical input on the sampling design, target chemicals, sampling 

methods, and data management. EPA used input from scientists that attended this workshop and from technical experts that participated in a series of study planning meetings to 

develop the final study design (USEPA 1999). During the year-long planning effort, EPA also 

completed the random lake selection process and identified the PBT chemicals to be included 

in the study.

a EPA’s other four national-scale probabilistic surveys include: the National Coastal Assessment (http://www.epa.gov/emap/

nca/), the Wadeable Streams Assessment (http://www.epa.gov/owow/streamsurvey/), the National Lakes Assessment 

(http://www.epa.gov/owow/lakes/lakessurvey/), and the National Rivers and Streams Assessment (http://www.epa.gov/

owow/riverssurvey/).
2

The National Study of Chemical Residues in Lake Fish Tissue

Introduction

Lakes and reservoirs became the focus of this study because they are environments where 

contamination accumulates. These waterbodies occur in a variety of landscapes (e.g., urban, 

agricultural, and wilderness), and they can receive contaminants from several sources, 

including direct discharges into the water, air deposition, and agricultural or urban runoff. 

Monitoring fish contamination in lakes and reservoirs is a critical activity for protecting 

human and ecosystem health because lakes and reservoirs provide important sports fisheries and other recreational opportunities. Lake ecosystems also provide critical habitat for 

aquatic species, and they support wildlife populations that depend on aquatic species for 

food. EPA’s 2008 Biennial National Listing of Fish Advisories (USEPA 2009) reports that 

43% of the Nation’s lake acres are under fish consumption advisories.

The National Lake Fish Tissue Study is the first national freshwater fish tissue survey to 

be based on a probabilistic sampling design, and it includes data on the largest set of PBT 

chemicals ever studied in fish. EPA worked with partner agencies in states, tribes, and other 

federal organizations over a four-year period (2000–2003) to collect fish from 500 lakes and 

reservoirs selected randomly from the estimated 147,000 target lakes and reservoirs in the 

conterminous United States (i.e., lower 48 states). The information provided in this report 

documents the national distribution of 268 PBT chemicals in predator fish species (e.g., bass 

and trout) and in bottom-dwelling fish species (e.g., carp and catfish) from lakes and reservoirs in the lower 48 states. National Lake Fish Tissue Study sampling design information 

and results have also been published in peer-reviewed journal articles by Olsen et al. (2009) 

and Stahl et al. (2009).

1.2 Study Objective

The specific objective of the National Lake Fish Tissue Study is to estimate the national 

distribution of the mean levels (i.e., composite average concentrations or “lake means”) of 

selected persistent, bioaccumulative, and toxic chemical residues in fish tissue from lakes 

and reservoirs of the conterminous United States.

The study design developed to support this objective generated a ground-breaking data set 

for EPA. Data from the National Lake Fish Tissue Study provided the agency with the first 

opportunity to:

n Develop national estimates of the median concentrations of PBT chemicals in lake fish;

n Estimate the percentage of lakes and reservoirs with fish tissue concentrations above a 

specified threshold related to human health; and

n Define a national baseline for tracking changes in concentrations of PBT chemicals in 

freshwater fish as a result of pollution control activities.
3

The National Study of Chemical Residues in Lake Fish Tissue

2.0 Study Design and Approach

2.1 Background

The National Lake Fish Tissue Study was conducted in four phases over a period of eight 

years. The initial planning phase began during the summer of 1998 and lasted for a year. 

Key activities during this phase included conducting a national study design workshop, 

applying a statistical approach to select lakes, and developing a list of target chemicals. It 

took another year to mobilize for the study. The second phase, mobilization, consisted of 

building a national network of partners, conducting orientation and training workshops for 

study participants, mapping and evaluating the lakes to determine their suitability for the 

study, and preparing standard operating procedures to guide implementation of the study. 

Implementation (the third phase of the study) included fish sample collection and tissue 

analysis. EPA and its partners began collecting fish samples in October 1999 and completed 

sampling in November 2003. All fish tissue samples were analyzed by May 2005. The final 

phase of the study involved statistical analysis of the fish tissue data and production of the 

final report. 

2.2 Study Design Development

Probability sampling provides the basis for estimating resource extent and condition, for characterizing trends in extent or condition, and for representing spatial pattern, all with known 

certainty. A probability sampling design has some inherent characteristics that distinguish 

it from other sampling designs. First, the population being sampled is explicitly described. 

Second, every element in the population has the opportunity to be sampled with known probability. Third, the selection process includes an explicit random element. Since the specific 

purpose of the National Lake Fish Tissue Study is to describe the condition of resources on a 

national basis, a probability-based design was an essential component of the study.

EPA’s Office of Research and Development (ORD) created an unequal probability survey 

design for the National Lake Fish Tissue Study that addresses the objective of the study. 

The unequal weighting prevented small lakes from dominating the representative sample 

drawn from the population of lakes. To support development of the final study design, EPA 

completed critical planning activities, which included hosting a study design workshop and 

selecting lakes and chemicals for the study. 

2.2.1 Study Design Workshop

In October 1998, EPA invited over 50 scientists from state, federal, and tribal agencies 

to participate in a two-day national study design workshop. Prior to the workshop, a 

workgroup of agency staff and contractors developed a draft study design to distribute to 
4

The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

workshop participants for review. Technical experts at the workshop provided input on fundamental elements of the study design, including the sampling design, chemicals of concern, 

and data management. The workgroup used recommendations from these experts to prepare 

the final study design prior to submitting it for external peer review in 1999. 

2.2.2 Statistical Selection of Lakes

The target population for this study was all lakes and reservoirs within the conterminous 

United States with a permanent fish population that met minimum size requirements, 

excluding the Laurentian Great Lakes and the Great Salt Lake. Use of the term “lakes” in 

this report refers collectively to lakes and reservoirs. A lake was defined as a permanent 

body of water of at least one hectare (2.47 acres) in surface area with a minimum of 

1,000 m2 of open (unvegetated) water and a depth of at least one meter. Since the lakes in 

this study also needed to have a permanent fish population, lakes subject to annual fish 

winterkill or recently stocked with fingerlings were rejected during the lake evaluation 

process. Stocked lakes with adult fish introduced at least three years prior to sampling were 

accepted as having a permanent fish population.

The sample frame used to generate the list of lakes was River Reach File Version 3 (RF3). 

When lake selection took place in early 1999, RF3 provided the best available GIS coverage 

for lakes and reservoirs in the United States. One important exception in the coverage was 

newly-constructed reservoirs. EPA obtained this information from the states and updated 

RF3 before initiating lake selection.

Statisticians from ORD selected an unequal probability sample of lakes according to procedures described by Stevens and Olsen et al. (2004). To obtain this sample, they divided 

the lakes into the following six size categories based on surface area of the lake expressed 

in hectares (ha), where one hectare is approximately 2.47 surface acres: 1–5 ha, >5–10 ha, 

>10–50 ha , >50–500 ha, >500–5,000 ha, and >5,000 ha. Table 1 lists the number of lakes 

available in RF3 by size category when lakes were selected for the study. Note that lakes 

in the smallest category (1–5 ha) accounted for more than 60% of the lakes available to be 

drawn, while lakes in the two largest categories (>500–5,000 ha and >5,000 ha) represented 

less than 1% of the lakes in RF3. The probability of selection for a lake depended on its surface area identified in the sample frame. Assigning varying probabilities for selection in each 

lake size category allowed a similar number of lakes to be drawn from each size category.

EPA established a goal of sampling 500 lakes in a period of four years. To insure that sufficient lakes were available to meet this target, ORD statisticians generated two statistically 

drawn sets of lakes: an initial list of 900 lakes and a reserve list of 900 lakes. Tables 2 and 3 

provide a breakdown of the number of lakes selected by size category and year for the initial 

and reserve lake lists. These tables highlight another important feature of the study design. 

The lakes selected for each sampling year comprise an annual statistical subset that provides 

a nationally-representative sample. Since the initial list of 900 lakes contained a larger than 

expected number of lakes that did not meet the criteria for inclusion in the study, reserve 

lakes were added in the final year of field sampling. During the four years of sampling, field 
The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

5

teams collected fish from 443 lakes on the initial lake list and 57 lakes on the reserve lake 

list to meet the sampling goal of 500 lakes. Appendix A provides a list of the 500 lakes and 

reservoirs sampled for the study. The National Study of Chemical Residues in Lake Fish 

Tissue: Study Design (USEPA 1999) and Quality Assurance Project Plan for Data Analysis 

Activities for the National Study of Chemical Residues in Lake Fish Tissue (USEPA 2005a) 

contain more detailed descriptions of the statistical lake selection process.

Table 1. Numbers of Lakes by Size Category in the Sample Frame (from RF3).

Lake area

(ha)

Number of

Lakes

Frequency

(%)

Cumulative

Number of

Lakes

Cumulative

Frequency

(%)

>1–5 172,747 63.8 172,747 63.8

>5–10 44,996 16.6 217,743 80.4

>10–50 40,016 14.8 257,759 95.2

>50–500 11,228 4.1 268,987 99.3

>500–5000 1,500 0.6 270,387 99.9

>5000 274 0.1 270,761 100.0

Table 2. Number of Lakes Selected for Potential Sampling by Size Category and Year.

Lake area

(ha) Year 1 Year 2 Year 3 Year 4 All Years

>1–5 39 41 47 47 174

>5–10 44 40 47 46 177

>10–50 32 47 46 25 150

>50–500 34 37 29 34 134

>500–5000 36 30 31 41 138

>5000 40 30 25 32 127

Total 225 225 225 225 900

Table 3. Number of Reserve Lakes Selected for Potential Sampling by Size Category 

and Year.

Lake area

(ha) Year 1 Year 2 Year 3 Year 4 All Years

>1–5 47 48 48 49 192

>5–10 45 52 40 42 179

>10–50 36 39 42 41 158

>50–500 36 26 40 22 124

>500–5000 38 29 30 37 134

>5000 23 31 25 34 113

Total 225 225 225 225 900
6

The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

2.2.3 Target Chemical Selection

EPA considered candidate chemicals for this study from two primary sources: the Agency’s 

persistent, bioaccumulative, and toxic (PBT) list of 451 chemicals and an integrated list of 

130 chemicals developed from several contemporary fish tissue and bioaccumulation studies 

(USEPA 1992, NOAA 1993, USEPA 1995, USEPA 1997, and USEPA 1998). Scientists 

participating in the 1998 study design workshop discussed the lists of candidate chemicals 

and provided comments on method availability and relevance for fish tissue. In March 1999, 

a team of analytical experts convened to review these lists of chemicals and select a list of 

chemicals for the study. They used the following criteria, along with input from study design 

workshop participants, to develop a target chemical list:

n Detailed information is available for the chemical.

n The chemical is of immediate concern and known to accumulate.

n One or more EPA programs consider the chemical to be important.

The final target chemical list consists of 268 PBT chemicals. This count includes individual 

and co-eluting PCB congeners (i.e., groups of two to six congeners that cannot be resolved 

to an individual level during chemical analysis), as well as multiple forms of a particular 

chemical (e.g., the six isomers of DDT, DDD, and DDE). Following is a summary of the 

target chemicals by chemical group:

	 n 2 metals (mercury and five forms of arsenic)

	 n 17 dioxins and furans

	 n 159 PCB individual and co-eluting congener measurements

	 n 46 pesticides

	 n 40 semivolatile organic chemicals (e.g., phenols, PAHs, and chlorobenzenes)

Table 4 lists the target chemicals for the National Lake Fish Tissue Study. Appendix B provides additional information about the chemicals, such as the Chemical Abstracts Service 

(CAS) numbers, method detection limits, and quantitation limits, which are also referred to 

as minimum levels (MLs).
The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

7

Table 4. Target Chemicals and Analytical Methods for the National Lake Fish Tissue Study.

Analytical Method Target Chemical

Total Mercury by Oxidation, Purge 

and Trap, and Cold Vapor Atomic 

Fluorescence Spectrometry (Method 

1631, Revision B with Appendix A - 

Digestion procedures for Total Mercury in 

Tissue, Sludge, Sediment, and Soil)

Mercury

Arsenic Speciation by Arsine 

Generation, Chromatography, and 

Atomic Absorption Spectrometry 

(Method 1632, Revision A)

Arsenic (III)

Arsenic (V)

Dimethylarsinic acid (DMA)

Monomethylarsonic acid (MMA)

Total inorganic arsenic

Polychlorinated Biphenyls by 

Isotope Dilution High-resolution Gas 

Chromatography/Mass Spectrometry 

(GC/MS) (Method 1668, Revision A)

209 congeners, including the following 12 “dioxin-like” congeners:

3,3',4,4'-TeCB

3,4,4',5-TeCB

2,3,3',4,4'-PeCB

2,3,4,4',5-PeCB

2,3',4,4',5-PeCB

2',3,4,4',5-PeCB

3,3',4,4',5-PeCB

2,3,3',4,4',5-HxCB

2,3,3',4,4',5'-HxCB

2,3',4,4',5,5'-HxCB

3,3',4,4',5,5'-HxCB

2,3,3',4,4',5,5'-HpCB

Dioxins and Furans by Isotope Dilution 

High-resolution GC/MS (Method 1613, 

Revision B)

2,3,7,8-TCDD

1,2,3,7,8-PeCDD

1,2,3,4,7,8-HxCDD

1,2,3,6,7,8-HxCDD

1,2,3,7,8,9-HxCDD

1,2,3,4,6,7,8-HpCDD

OCDD

2,3,7,8-TCDF

1,2,3,7,8-PeCDF

2,3,4,7,8-PeCDF

1,2,3,4,7,8-HxCDF

1,2,3,6,7,8-HxCDF

1,2,3,7,8,9-HxCDF

2,3,4,6,7,8-HxCDF

1,2,3,4,6,7,8-HpCDF

1,2,3,4,7,8,9-HpCDF

OCDF

Organochlorine Pesticides by Gas 

Chromatography/Halide Specific 

Detector (GC/HSD) (Method 1656, 

Revision A)*

2,4'-DDD (TDE) ‡

2,4'-DDE ‡

2,4'-DDT ‡

4,4'-DDD (TDE)

4,4'-DDE

4,4'-DDT

Aldrin

cis- and trans-Nonachlor

Dicofol

Dieldrin

Endosulfan sulfate

Endosulfan I

Endosulfan II

Endrin

Ethalfluralin (Sonalan)

Heptachlor

Heptachlor epoxide

Isodrin

Kepone (Chlordecone)

Methoxychlor

Mirex 

Octachlorostyrene

Oxychlordane

Pendimethalin (Prowl)

Pentachloronitrobenzene (PCNB)

cis-Permethrin and trans-Permethrin

Toxaphene

Trifluralin

α -BHC

α -Chlordane (cis-Chlordane)

β -BHC

ʏ -BHC (Lindane)

ʏ -Chlordane (trans-Chlordane)

δ BHC

Pentachloroanisole

‡ Chemicals were added to the target chemical list after Year 1 of the 

study.

*PCB Aroclors were not target chemicals for this study, but seven Aroclors were analyzed incidentally using Method 1656, 

Revision A, including Aroclors 1016, 1221, 1232, 1242, 1248, 1254, 1260.
8

The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

Table 4. (continued)

Analytical Method Target Chemical

Organophosphorus Pesticides by Gas 

Chromatography/Flame Photometric 

Detector (GC/FPD) (Method 1657, 

Revision A)

Chlorpyrifos

Diazinon

Disulfoton

Disulfoton sulfone

Ethion

Paraoxon

Parathion (ethyl)

Terbufos

Terbufos sulfone

Semivolatile Organic Chemicals by 

Isotope Dilution GC/MS (Method 1625, 

Revision C with modifications for tissue)

3,3'-dichlorobenzidine

1,2,4,5-Tetrachlorobenzene

1,2,4-Trichlorobenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

2,4,5-Trichlorophenol

4,4'-Methylenebis 

(2-chloroaniline)

4-Bromophenyl phenyl ether

4-Nonylphenol

Acenaphthene (PAH)

Acenaphthylene

Anthracene (PAH)

Benzo(a)anthracene (PAH)

Benzo(a)pyrene (PAH)

Benzo(b)fluoranthene (PAH)

Benzo(g,h,i)perylene (PAH)

Benzo(j)fluoranthene (PAH)

Benzo(k)fluoranthene (PAH)

Bis(2-ethylhexyl) phthalate

Butyl benzyl phthalate

Chrysene (PAH)

Dibenzo(a,h)anthrancene (PAH)

Di-n-butyl phthalate

Diethylstilbestrol (DES)

Fluoranthene (PAH)

Fluorene (PAH)

Hexachlorobenzene

Hexachlorobutadiene

Indeno(1,2,3-cd)pyrene (PAH)

Naphthalene (PAH)

Nitrobenzene

Pentachlorobenzene

Pentachlorophenol

Perylene (PAH)

Phenanthrene (PAH)

Phenol

Phenol, 2,4,6-tris(1,1 dimethylethyl)-

Pyrene (PAH)

Tetrabromobisphenol A
The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

9

2.3 Mobilization

August 1999 marked the beginning of the mobilization phase of the National Lake Fish 

Tissue Study. EPA initiated this phase by conducting orientation and training workshops for 

states and other potential fish study participants. These workshops were a key activity in 

building a national network of partners to support the study. Another activity closely tied to 

the workshops was the mapping and reconnaissance of the 900 lakes on the initial list of statistically drawn candidate lakes for the study. Lake lists were distributed to the states prior 

to the workshops, allowing discussion of lake reconnaissance during the workshops. A final 

activity completed during this phase of the study was the development of quality assurance 

and field sampling plans. Preparation of these plans provided the basis for successful implementation of the study.

2.3.1 Orientation and Training Workshops

EPA introduced study participants to the National Lake Fish Tissue Study design, scope, and 

procedures through regional orientation and training workshops. Nearly 100 representatives 

from state, tribal, and other federal agencies attended a series of ten workshops held at the 

Agency’s Regional Offices between August 1999 and June 2000 (Figure 1). Presentations 

at the workshops included an overview of the study design, a description of the sampling 

program, and instruction on the standard operating procedures (SOPs) and quality 

assurance/quality control (QA/QC) requirements for fish collection, handling and shipping. 

Workshop activities also included a discussion about lake reconnaissance (e.g., sampling 

site assessments and lake access issues) and a forum for planning field sampling (e.g., 

addressing scheduling questions and discussing personnel needs). Study participants received 

a variety of materials at the workshops, including training slides, a copy of the Sample 

Collection Activities Quality Assurance Project Plan (QAPP) (USEPA 2000a), and maps of 

the lakes selected in 

their jurisdictions. 

Sampling 

coordinators from 

each participating 

office or agency 

viewed the training 

materials, read the 

QAPP, and verified 

that they read all 

the information 

and understood 

the procedures and 

requirements.

Figure 1. Locations of 10 regional orientation and training 

workshops.
10

The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

2.3.2 Partnerships

A national network of partners provided critical support for the planning, mobilization, and 

implementation phases of the study. Figure 2 presents an organizational chart for key participants in the study. The Office of Science and Technology (OST) relied on fish study coordinators in each EPA Region to recruit study participants from states, tribes and other federal 

agencies in their geographic areas. These regional coordinators were also instrumental in 

planning logistics for the orientation and training workshops (Section 2.3.1). The workshops 

served as the primary vehicle to obtain formal commitments to participate in the study. The 

external network of partners that provided long-term support for the study consisted of 

47 states, three tribes, and two other federal agencies (the National Park Service and Tennessee Valley Authority). Through their combined efforts, they accomplished the majority of the 

lake evaluations and fish collection from the 500 lakes and reservoirs across the country.

Figure 2. National Lake Fish Tissue Study participants.

National Lake Fish Tissue Study Management 

EPA/Office of Water (OW)/Office of Science and Technology (OST)

Field Sampling Support

EPA/OW/OST

Tetra Tech, Inc.

Analytical Support

EPA/OW/OST

Computer Sciences Corp.

Statistical Support

EPA/ORD/EMAP

(Corvallis, Oregon)

EPA Regional 

Coordinators

10 EPA Regions

Participating 

Field Teams

47 States

3 Tribes

National Park Service

Tennessee Valley Authority

Tetra Tech, Inc.

ManTech Environmental Sample Control Center

Computer Sciences Corp.

Sample Preparation Laboratory

AXYS Analytical Services, Ltd.

Analytical Laboratories

AXYS Analytical Services, Ltd. (PCBs, dioxins/furans)

Batelle Marine Sciences (mercury, arsenic)

Batelle Ocean Sciences (semivolatile organic chemicals)

Pacific Analytical, Inc. (pesticides)
The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

11

Within EPA, OST received significant support from ORD, the Office of Pesticides, Prevention, and Toxic Substances (OPPTS), and the ten Regional Offices. ORD’s Environmental 

Monitoring and Assessment Program (EMAP) developed the statistical framework for the 

study, implemented the lake selection process, managed the target lake list throughout the 

study, and performed the statistical analysis of the data. Support from OPPTS focused on 

study planning, particularly in identifying the target chemicals. The Office of Pollution Prevention and Toxics within OPPTS also provided Agency leadership and coordination for 

activities conducted under the PBT Initiative, including this study (the largest project sponsored under the Initiative). Besides organizing workshop logistics and recruiting partners, 

the EPA Regions were actively involved in evaluating lakes and collecting fish for the study. 

In areas where external or regional resources were not available to complete these tasks, 

OST provided national contractor support for lake reconnaissance and fish collection.

2.3.3 Lake Evaluations

A critical component in mobilizing for the study was reconnaissance of the candidate lakes. 

Section 2.2.2 describes the statistical selection of lakes for the study, which resulted in an 

initial list of 900 candidate lakes and a reserve list of another 900 lakes. Study participants 

evaluated each of the initial 900 lakes to determine if they met the definition of a lake for 

the study (Section 2.2.2), if they were physically accessible, and if landowners would grant 

permission to access lakes on private property. They furnished a complete record of the 

reconnaissance information, including reasons why sites failed to meet the lake criteria and 

information regarding physical barriers or landowner denials that prevented access to lakes 

that did meet the criteria.

The lake reconnaissance process involved both desktop and ground truth exercises. National 

contractors used mapping software to generate maps for each of the initial 900 lakes and distributed these maps to study participants. The maps were used to identify any obvious issues 

regarding lake access. A site visit was necessary to determine lake status if regional, state, or 

local agencies had no information on record for a candidate lake. During the final sampling 

year (2003), participants repeated this process to evaluate an additional 101 lakes from the 

reserve list. Assessment of 1001 lakes resulted in the identification of 500 viable sampling 

sites. All reconnaissance information was tracked and tabulated on a national lake spreadsheet. Appendix A contains the final list of 500 lakes and reservoirs sampled for the study.

2.3.4 Quality Assurance and Field Sampling Plans

During the mobilization phase, EPA developed two quality assurance project plans (QAPPs). 

The Sample Collection Activities QAPP (USEPA 2000a) describes all requirements and procedures related to the field sampling program, along with the roles and responsibilities of staff 

supporting the field program. The Analytical Control and Assessment Activities QAPP (USEPA 

2000b) describes all the requirements and procedures for sample preparation, fish tissue analysis, and analytical data review, as well as roles and responsibilities for analytical activities 

staff. EPA also developed an abbreviated version of the Sample Collection Activities QAPP to 

serve as a field manual for the fish sampling teams. Copies of this Field Sampling Plan (USEPA 

2000c) and both QAPPs are available online at www.epa.gov/waterscience/fishstudy/.
12

The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

2.4 Sample Collection

Fish sampling and fish tissue analysis comprised the implementation phase of the National 

Lake Fish Tissue Study. EPA designed the study to include four years of fish collection. After 

a brief pilot in the fall of 1999 to test sampling logistics, participants conducted full-scale 

fish sampling from 2000 through 2003. Each year, field sampling teams collected fish from 

approximately 125 lakes distributed across the lower 48 states. These field teams collected 

the majority of the fish samples during the summer and fall of each sampling year. This 

schedule coincided with the peak period for recreational fishing activity and allowed sampling teams to avoid the spawning period for most target species. 

2.4.1 Sampling Locations

The potential sampling locations were limited to the target population of approximately 

147,000 lakes in the lower 48 states that met the study’s definition of a lake (Section 2.2.2). 

Due to resource and study design constraints, Alaska and Hawaii were not included in the 

study. EPA worked with study partners to collect fish from 500 lakes randomly selected from 

the target population. The 500 sampling locations included both private and public access 

lakes that ranged in size from one to about 384,615 hectares (or from 2.5 to about 950,000 

surface acres). Figure 3 shows the locations of the 500 lakes sampled for the study, and 

Appendix A provides a list of these locations. Sampling sites occurred in each of the lower 

48 states except Delaware because no lakes or reservoirs were randomly drawn in Delaware.

Figure 3. National Lake Fish Tissue Study sampling locations (500 lakes).
The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

13

2.4.2 Target Species

The National Lake Fish Tissue Study included two distinct ecological groups of fish, predators (e.g., bass or trout) and bottom dwellers (e.g., carp or catfish). This permitted monitoring of a variety of habitats, feeding strategies, and physiological factors that might result in 

differences in the bioaccumulation of chemicals. Predators were included because they are 

good indicators of persistent contaminants that may be biomagnified through several trophic 

levels of the food web. Bottom dwellers were included because they may accumulate high 

contaminant concentrations through direct contact with contaminated sediments or by consuming benthic organisms that live in contaminated sediments. Twelve predator species and 

six bottom-dwelling species were targeted to limit the number of fish species included in the 

study. Table 5 lists the recommended target species for the study.

Table 5. Recommended Target Species for Lakes and Reservoirs (in Order of Preference).

Family name Common name Scientific name

Predator/Gamefish Species

(in order of preference)

Centrarchidae Largemouth bass Micropterus salmoides

Smallmouth bass Micropterus dolomieu

Black crappie Pomoxis nigromaculatus

White crappie Pomoxis annularis

Percidae Walleye Sander vitreus

Yellow perch Perca flavescens

Percichthyidae White bass Morone chrysops

Esocidae Northern pike Esox lucius

Salmonidae Lake trout Salvelinus namaycush

Brown trout Salmo trutta

Rainbow trout Oncorhynchus mykiss

Brook trout Salvelinus fontinalis

Bottom-dwelling 

Species

(in order of 

preference)

Cyprinidae Common carp Cyprinus carpio

Ictaluridae Channel catfish Ictalurus punctatus

Blue catfish Ictalurus furcatus

Brown bullhead Ameiurus nebulosus

Yellow bullhead Ameiurus natalis

Catostomidae White sucker Catostomus commersoni
14

The National Study of Chemical Residues in Lake Fish Tissue

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To select target fish species, EPA used the following criteria from Guidance for Assessing 

Chemical Contaminant Data for Use in Fish Advisories, Volume 1: Fish Sampling and 

Analysis, Third Edition (USEPA 2000d):

n The species is abundant and commonly consumed in the study area.

n It may potentially accumulate high concentrations of chemicals.

n The species is easy to identify, and it has a wide geographic distribution.

n Adult specimens are large enough to provide adequate tissue for analysis.

In areas where the recommended target species were not available, field teams applied these 

criteria to identify additional target species. Appendix C provides a summary of the fish species collected for the study.

2.4.3 Composite Samples

The sampling goal for field teams was to collect separate composite samples of a predator 

fish species and a bottom-dwelling species from each lake or reservoir. Composite 

samples consisted of multiple adult fish (five preferred) of the same species and similar size 

(i.e., lengths of all fish in the composite were within 75% of the length of the largest fish). 

Collecting composite samples served as a form of physical averaging and offered a costeffective approach for obtaining an estimate of the mean chemical concentrations in fish 

tissue for a lake or reservoir. Compositing also ensured that an adequate amount of tissue 

was available for analysis of all the target chemicals.

During the four-year sampling period, field teams collected 486 predator composites and 

395 bottom-dweller composites from the 500 sampling locations. Predator and bottomdwelling species did not occur together at every sampling site; however, if either a predator 

or bottom- dweller species were present, the target lake was sampled. In addition, field teams 

collected replicate composite samples from about 10% of the lakes to allow evaluation of 

sampling variability. This sampling effort produced 70 replicate predator composites and 52 

replicate bottom-dweller composites.

2.4.4 Sampling Methods

Field sampling procedures developed for the National Lake Fish Tissue Study followed the 

recommendations in Guidance for Assessing Chemical Contaminant Data for Use in Fish 

Advisories, Volume I: Fish Sampling and Analysis, Third Edition (USEPA 2000d). Specific 

sampling protocols for this study are detailed in the Field Sampling Plan (USEPA 2000c) and 

Sample Collection Activity QAAP (USEPA 2000a).

Fish sampling teams used active (e.g., electrofishing) and passive (e.g., gill netting) collection methods to obtain the desired target numbers and species of fish. Experienced fisheries 

biologists determined the appropriate type of fishing gear for a particular target lake and 
The National Study of Chemical Residues in Lake Fish Tissue

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15

identified the species available for compositing. After collecting the fish, team members measured total body length of each fish in a composite, wrapped whole fish in contaminant-free 

materials, packed them on dry ice in shipping coolers, and used overnight delivery to ship 

the fish samples (under Chain of Custody) to the laboratory responsible for sample preparation. Field teams recorded all site and sampling information on a standard Field Record 

Form and enclosed it with the samples in the shipping coolers. 

2.4.5 Sample Collection Quality Assurance/Quality Control (QA/QC)

EPA emphasized experience and consistency in recruiting, training, and coordinating field 

sampling support for the National Lake Fish Tissue Study. To initiate this effort, detailed 

Standard Operating Procedures were developed to establish consistent methods and requirements for fish collection, handling, and shipping. These study-specific procedures were 

presented to study participants during the orientation and training workshops. EPA also 

distributed a Field Sampling Plan (USEPA 2000c) to every field sampling team. This field 

manual contained a project description, the comprehensive SOPs for sample collection, and 

instructions for completing fish labels and field and shipping forms. In the field, highly qualified fisheries biologists led the sampling teams. Under their leadership, every fish sample collected during the four sampling years of the study arrived intact at the sample preparation 

laboratory. The fact that no fish samples were lost throughout the four field seasons demonstrates how carefully the field teams adhered to the sampling and shipping protocols.

EPA employed additional measures to maintain quality control for fish sampling. Each 

year, the Sample Control Center distributed identical field sampling supplies to every field 

team across the country. These supplies included materials for wrapping and packaging fish 

specimens (e.g., solvent-rinsed foil and food-grade plastic tubing), coolers for shipping, and 

standard forms and labels to document sample collection and shipping. To reduce the risk 

of introducing contamination, field teams shipped whole fish to the laboratory where fish 

tissue samples were prepared in a strictly-controlled environment. Another provision for 

quality control was centralizing the daily coordination and tracking of sample shipments at 

the national level. This process prevented coolers from becoming lost or delayed to an extent 

that would compromise the condition of the samples during transit to the laboratory. When 

each cooler reached the laboratory, staff inspected it for damage and contacted the Sample 

Control Center to verify that the samples it contained arrived frozen and in good condition. 

The laboratory forwarded all associated paperwork (e.g., Field Record Forms and Chainof-Custody Forms) to the national sampling support contractor to verify completeness and 

accuracy. A final QA activity involved collecting replicate samples at a minimum of 10% of 

the lakes to provide data for developing estimates of sampling variability (Section 3.5).
16

The National Study of Chemical Residues in Lake Fish Tissue

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2.5 Sample Analysis

Laboratories analyzed different fish tissue fractions for the two types of composite samples 

collected for the study: fillets for the predator composites and whole bodies for the bottomdweller composites. This approach allowed development of data relevant to both human and 

ecosystem health. A network of four commercial laboratories (Figure 2) applied seven standard EPA methods to analyze the fish tissue for the 268 target chemicals (Table 4). One of 

these laboratories was also responsible for sample preparation, which involved filleting and 

grinding fish samples, dividing the tissue into sub-samples (i.e., aliquots), and shipping the 

fish tissue samples to the other laboratories for analysis. A large tissue volume was necessary 

to complete all the chemical analyses. The sample preparation laboratory processed and distributed 560 grams (about 20 ounces) of tissue for each fish composite sample. This volume 

provided sufficient tissue for measuring the lipid content of each sample and running required 

portions of the sample through the series of analytical methods. It also provided reserve 

tissue for the option of re-analyzing samples and archiving frozen fish tissue for future use.

2.5.1 Non-routine Samples

This study defined a composite sample as one containing five fish of the same species. An 

additional requirement for each composite was that the smallest fish in the composite be at 

least 75% of the length of the largest fish (Section 2.4.3). Composite samples that did not 

meet either of these requirements were designated as non-routine samples. Prior to making a 

decision about whether to retain and analyze a non-routine sample, EPA evaluated species, 

number of specimens, and specimen lengths. This evaluation resulted in one of the following decisions: accept non-routine composites that had less than five specimens, but provided 

sufficient tissue for analysis; accept composites of more than five specimens in order to provide enough tissue for analysis; or reject individual specimens or entire composites that fell 

outside of study parameters. Non-routine samples that met the first two decision criteria 

were accepted for analysis. Individual specimens that did not meet the 75% length rule were 

eliminated (with rare exceptions for fish whose lengths were less than 5mm shorter than the 

minimum allowable length). 

Over the four-year sampling period, about 24% of the composite samples were non-routine 

samples. EPA rejected about 2% of the total composite samples submitted by the field teams. 

Rejection of these samples was based on submission of composites containing inappropriate 

species or insufficient tissue, predator specimens mistakenly filleted in the field, or fish collected from the wrong lake (i.e., a lake not on the target lake list).

2.5.2 Sample Preparation

AXYS Analytical Services, Ltd. in Sidney, British Columbia served as the sample preparation 

laboratory for the duration of the study. In accordance with EPA specifications, the laboratory prepared bottom-dwelling species as whole fish composites. This involved grinding 

the entire specimen, including the head, skin, internal organs, muscle, and bones. Laboratory staff combined ground tissue from each whole fish in the composite and thoroughly 

homogenized the fish tissue before extracting sub-samples for analysis. Predator species were 
The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

17

prepared as skin-on fillet composites (scales removed and belly flap attached). In preparing 

predator composites, the entire fillet was removed from both sides of each fish in the composite and all the fillets were ground together. Laboratory staff ensured that the tissue was 

completely homogenized before preparing sample aliquots for analysis. AXYS distributed 

sample aliquots to three other laboratories for analysis, and they shipped additional aliquots 

to a sample repository for archiving.

All sample preparation activities (e.g., filleting and tissue homogenization) were performed 

according to procedures in EPA’s Guidance for Assessing Chemical Contaminant Data for 

Use in Fish Advisories, Volume 1: Fish Sampling and Analysis (Third Edition, November 

2000) (USEPA 2000d). The National Lake Fish Tissue Study Analytical Control and 

Assessment Activities QAPP describes study-specific procedures for sample preparation 

(USEPA 2000b). 

2.5.3 Laboratory Network

Four laboratories analyzed samples for this study: AXYS Analytical Services, Ltd., Sidney, 

British Columbia; Battelle Marine Sciences, Sequim, Washington; Battelle Ocean Sciences, 

Duxbury, Massachusetts; and Pacific Analytical, Inc., Carlsbad, California. EPA used multiple laboratories to access their expertise for specific chemical analyses. AXYS Analytical 

Services analyzed fish tissue samples for PCBs and dioxins and furans, in addition to serving 

as the sample preparation laboratory. Battelle Marine Sciences performed the metals analyses (mercury and arsenic), whereas Battelle Ocean Sciences performed the analyses for semivolatile organic chemicals (e.g., phenols, phthalates, and polycyclic aromatic hydrocarbons 

or PAHs). Pacific Analytical analyzed the tissue samples for pesticides.

2.5.4 Analytical Methods

Laboratories analyzed fish tissue samples using seven standard EPA methods: two methods for metals (mercury and arsenic), two methods for pesticides (organochlorine and 

organophosphate pesticides), and a single method for each of the three other chemical 

groups (PCBs, dioxins and furans, and semivolatile organic chemicals). Each method specifies procedures for analysis, QA/QC requirements, and reporting limits. Table 4 lists the 

method number and title, along with the number and group of target chemicals covered 

by the method. At EPA’s direction, laboratories made study-specific modifications to two 

of the methods to achieve lower detection limits: Method 1613B for dioxins and furans 

and Method 1656A for organochlorine pesticides. Appendix D provides more detailed 

information for each of the methods and describes the modifications to Methods 1613B 

and 1656A to achieve lower detection limits. Method-specific information is also available in the QAPP for Analytical Control and Assessment Activities in the National Study 

of Chemical Residues in Lake Fish Tissue (USEPA 2000b) and in the Quality Assurance 

Report for the National Study of Chemical Residues in Lake Fish Tissue: Analytical Data 

for Years 1 through 4 (USEPA 2005b). Both documents are posted online at www.epa.gov/

waterscience/fishstudy/. 
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The National Study of Chemical Residues in Lake Fish Tissue

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2.5.5 Sample Analysis QA/QC

EPA stressed consistency and comparability in planning and implementing QA/QC 

measures for sample analysis. An initial step in promoting consistency for fish tissue 

analysis was centralizing sample filleting (predator composites only) and the grinding and 

homogenization of tissue in a strictly-controlled, contaminant-free environment at a single 

laboratory. Using the same laboratory for each type of analysis throughout the study was 

also crucial for maintaining consistency in generating results. Comparability of study results 

was achieved by using a single set of methods to analyze all fish samples collected during the 

study. Applying consistent method detection limits (MDLs) and QC acceptance criteria also 

insured comparable results.

EPA maintained quality control through a number of other laboratory and data review activities. Prior to initiating sample analysis, EPA’s Sample Control Center (SCC) verified that each 

laboratory participating in the study could achieve the specified detection limits and quantitation levels. The SCC also required laboratories to analyze initial and ongoing QC samples to 

demonstrate their ability to obtain precise and accurate results with the standard methods. In 

addition, the laboratories used pure and traceable reference standards during sample analysis, 

analyzed sample preparation and analysis blanks to demonstrate the absence of contamination, and submitted data reports in standard formats. The SCC received and reviewed the 

analytical data from the laboratories using a standard process for data quality assessment. 

The Quality Assurance Report for the National Study of Chemical Residues in Lake Fish 

Tissue: Analytical Data for Years 1 through 4 (USEPA 2005b) provides detailed descriptions 

of all the standard procedures for sample analysis, data reporting, and data review.

2.6 Statistical Analysis of Study Data

Tissue concentrations for each target chemical (e.g., mercury) or chemical group (e.g., PCBs) 

and fish composite type comprise the series of national data sets analyzed for the National 

Lake Fish Tissue Study. Statistical analysis of these fish tissue data sets involved application 

of R statistical software (R Development Core Team 2004) to estimate percentiles (Section 

3.0) and the cumulative distribution of tissue concentrations (Section 3.1.4) for the sampled 

population of lakes. This statistical package was selected for tissue data analysis because it is 

readily available, it has robust capabilities, and statisticians in EPA’s Office of Research and 

Development (ORD) have extensive experience using this software for analysis of unequal 

probability survey data (e.g., Environment Monitoring and Assessment Program (EMAP) 

survey data). Analysis of the fish tissue data incorporated elements of the survey design, 

along with information from the field sampling operations and laboratory analyses. The 

statistical analysis process included the following essential steps:

n compiling lake evaluation information to determine the status for each lake in the study 

(Section 2.3.3),

n adjusting the survey design (sample) weights based on lake status,

n estimating the number of lakes within the conterminous United States that meet the 

project definition of a lake (i.e., the target population),
The National Study of Chemical Residues in Lake Fish Tissue

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19

n estimating the number and proportion of lakes in the sampled population, and

n estimating the cumulative distribution and percentile concentrations of the target 

chemicals in each fish tissue fraction (i.e., fillets for predator composites and whole 

bodies for bottom-dweller composites).

Activities in the last four steps are summarized in Sections 2.6.1 through 2.6.4. Section 

2.6.5 contains a brief description of statistical analysis QA/QC.

2.6.1 Calculating the Sample Weights

A critical activity for analyzing data from a study with an unequal probability survey design 

is deriving the sample weights. For this study, lake size (surface area) was used to assign a 

probability of selection, or inclusion probability, to each lake. The lakes were divided into 

six size categories with inclusion probabilities assigned to each to allow a similar number of 

lakes to be selected from each size category (Section 2.2.2). Statistical analysis of data for 

this unequal probability sample of lakes is more complex, and it requires that all analyses 

use weights derived from the unequal probability of selection (Thompson 1992).

The statistical weight of each lake is the inverse of its probability of selection or inclusion 

probability. The inclusion probability was determined by the goal of obtaining approximately an equal number of lakes to sample in each size category. During the lake selection process, the inclusion probability was adjusted for the three smaller size categories to 

account for the larger number of lakes that would not meet the study definition of a lake. 

These adjustments were as follows: increase by 40% for 1–5 hectares (ha), increase by 30% 

for 5–10 ha, and increase by 20% for 10–50 ha. No adjustment was required for the remaining size categories (50–500 ha, 500–5,000 ha, and >5,000 ha). Initial sample weights were 

calculated for each lake based on the unequal probabilities of selection. The inclusion probabilities for the smallest to the largest lake size categories were as follows: 0.001065142, 

0.003822562, 0.003898441, 0.011756323, 0.088000000, and 0.452554745. These probabilities resulted in expected total sample sizes of 184, 172, 156, 132, 132, and 124 lakes, 

respectively. They also resulted in initial design weights of 938.84, 261.60, 256.51, 85.06, 

11.36, and 2.21, respectively. Note that the sample weights are expressed as numbers of 

lakes. The final sample weights were derived from adjusted inclusion probabilities based 

on the total number of lakes identified for potential sampling at the conclusion of the lake 

evaluation process. This weight adjustment was made individually for each lake size category. The adjusted weight is the initial weight multiplied by the ratio of the number of lakes 

in the sample frame divided by the product of the number of lakes evaluated and their initial 

weight. For example, the adjustment for lakes in the >5000 ha size category is: 

1.971223

(139 2.21)

274 2.21 =
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The National Study of Chemical Residues in Lake Fish Tissue

Study Design and Approach

2.6.2 Estimating the Size of the Target Population of Lakes

The data necessary for estimating the number of target lakes are the evaluation status results 

compiled for all lakes statistically drawn for potential field sampling. Diaz-Ramos et al. 

(1996) describe the statistical procedure used to estimate the total (target) population from 

the unequal probability sample of lakes. An associated variance estimate, called a local 

neighborhood variance estimate, is described by Stevens and Olsen (2003). Procedures for 

estimating both the target population size and variance are available online at http://www.

epa.gov/nheerl/arm/analysispages/r_design_guide.htm in the R library for the Office of 

Research and Development’s National Health and Environmental Effects Research Laboratory in Corvallis, Oregon. An option also exists to complete the same estimates for subregions of the conterminous United States. However, unless the sample size is sufficiently 

large, the confidence intervals of the sub-region estimates may be so large that the estimates 

provide little information. Sub-region estimates were not derived for this study because the 

sample size was insufficient to develop estimates with reasonable confidence intervals.

2.6.3 Estimating the Size of the Sampled Population of Lakes

The target population of lakes for this study included lakes on both public and private 

lands. All target lakes met the study definition of a lake (Section 2.2.2), but some of these 

lakes could not be sampled. Landowner denial to access lakes on private property was a 

major factor in preventing field teams from sampling privately-owned target lakes. Another 

important factor was physical barriers that made some target lakes inaccessible (e.g., remote 

locations with no road access or reservoir draw downs). EPA used the number of inaccessible 

target lakes to develop an estimate of the sampled population of lakes (i.e., the number of 

target lakes that could be sampled). Table 6 in Section 3.0 presents the estimated number 

of lakes by evaluation status (e.g., non-target, target, and inaccessible target), lake size 

category, and composite type.

2.6.4 Estimating Fish Tissue Concentrations

EPA developed national estimates of fish tissue concentrations in each fish composite type 

(i.e., predator fillets and bottom-dweller whole bodies) for all the target chemicals. Tissue 

concentration data from laboratory analysis of the fish composite samples, along with the 

final sample weights associated with each lake, were required to derive these estimates. 

The tissue concentrations are reported as percentiles, including the 50th percentile or 

median concentration, for each target chemical and composite type. EPA estimated the 

cumulative distribution of fish tissue concentrations for the sampled population of lakes 

using a procedure described by Diaz-Ramos et al. (1996) entitled, “Estimation Method 1: 

Cumulative Distribution Function for Proportion of a Discrete or an Extensive Resource.” 

The estimated proportion ( ) below a specific value for a concentration (C) is:
The National Study of Chemical Residues in Lake Fish Tissue

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21

where: xi

 = 1 if concentration for i

th lake is below C and equals 0 otherwise,

 wi

 = the adjusted weight for i

th lake, and

 n = total number of lakes sampled.

Variance estimates were derived using the local neighborhood variance estimator described 

by Stevens and Olsen (2003 and 2004). To complete these analyses, EPA utilized the 

R statistical software (R Development Core Team 2004) and an R contributed library for 

probability survey population estimation (spsurvey) that is available online at the following 

Internet address: http://www.epa.gov/nheerl/arm/analysispages/software.

2.6.5 Statistical Analysis QA/QC

EPA focused on QA/QC activities to achieve accuracy and reproducibility during statistical 

analysis of the fish tissue data and review of the results. These activities began with a series 

of internal checks of the input data files to verify the consistency and completeness of the 

data. For example, the composite sample identification numbers were compared to the lake 

site identification numbers and the sample (composite) types to ensure that no miscoding 

occurred. National study management team members also checked the consistency of the 

output files. Any inconsistencies identified by the team were traced to errors in the input 

files and resolved by correcting these files and repeating the analyses. The final step in 

reviewing statistical analysis of the data involved re-analyzing a subset of the data to verify 

the reproducibility of the results. A QAPP describing data analysis activities for the National 

Lake Fish Tissue Study (USEPA 2005a) provides additional information about statistical 

analysis QA/QC. It is available online at www.epa.gov/waterscience/fishstudy/.
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The National Study of Chemical Residues in Lake Fish Tissue

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23

The National Study of Chemical Residues in Lake Fish Tissue

3.0 Results

The National Lake Fish Tissue Study is the first statistically-based national assessment of 

freshwater fish contamination to be completed in the United States. The study applies an 

unequal probability design. It is essential to understand two important points about this 

design:

n The 486 predator composites and the 395 bottom-dweller composites collected during 

the study from the 500 sampling locations (Section 2.4.3) each comprise nationallyrepresentative samples whose results can be extrapolated to tens of thousands of lakes 

and reservoirs in the lower 48 states.

n The unequal probability design requires application of sample weights (Section 2.6.1) 

to the fish tissue data to develop national estimates of fillet (predators) and wholebody (bottom dwellers) tissue concentrations for each of the 268 target chemicals. The 

sample weights are derived from the various probabilities assigned to each of the six 

lake size categories in the study design (Section 2.2.2).

Two statistical sets of lakes, the target population and the sampled population, define how 

broadly the fish tissue concentration results apply to lakes and reservoirs in the United 

States. The target population consists of all lakes and reservoirs in the lower 48 states with a 

permanent fish population that met the study lake size requirements. There are an estimated 

147,000 lakes in the target population for this study. The sampled population consists of all 

target lakes that were accessible for fish collection. Under ideal circumstances, the target and 

sampled populations should coincide. However, for this study, the sampled population is a 

subset of the target population. A number of target lakes were not accessible to field sampling teams because the lakes were either located in remote wilderness areas or on private 

property where landowners denied EPA permission to sample them (Table 6). There is a different sampled population for each composite type based on differences in the occurrence of 

predators and bottom dwellers in the 500 sampled lakes. The sampled population for predators contains an estimated 76,559 lakes, and the sampled population for bottom dwellers 

consists of an estimated 46,190 lakes. All predator and bottom-dweller results presented in 

this report apply to these sampled populations of lakes.
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The National Study of Chemical Residues in Lake Fish Tissue

Results

Table 6. Estimated Number of Lakes by Evaluation Status, Lake Size Category, and Composite Type

Estimated Number of

Lakes By Evaluation

Status

Lake area (hectares) Total

(95% Confidence

Interval)

>1–5 >5–10 >10–50

>50–

500

>500–

5000 >5000

Lakes in RF3 (Actual) 172,747 44,996 40,016 11,228 1,500 274 270,761

Non-Target Lakes 123,418±8%

Saline Lake 1,809 466 710 217 29 8 3,240±66%

Not a Lake 47,031 15,620 11,365 2,898 380 6 77,300±12%

Lake <1 hectare 5,427 - - - - - 5,427±63%

No Fish in Lake 17,184 3,031 1,657 72 - 2 21,947±28%

No Permanent Fish 9,044 3,730 2,368 362 - - 15,505±30%

Target Population of Lakes 147,343±7%

Inaccessible Target Lakes

Land Owner Denied 

Access 39,795 5,595 5,209 724 - - 51,424±16%

Lake Physically 

Inaccessible 9,948 4,430 2,605 362 10 - 17,355±29%

Sampled Population of Lakes

Predator Sampled 

Population 41,604 16,101 11,191 6,375 1,032 256 76,559±12%

Bottom Dweller 

Sampled Population 19,898 11,602 8,160 5,360 935 235 46,190±17%

Total Sampled 

Population* 42,508 12,123 16,101 6,592 1,081 258 78,664±12%

*The total sampled population of lakes includes lakes that yielded either predator or bottom-dweller species.

Data analysis focused on the study objective to develop estimates of the national distribution of the mean levels (i.e., “lake means” or composite average concentrations) of the target 

chemicals (Section 2.2.3) in predator fillets and whole bodies of bottom dwellers. These 

national distributions of fillet and whole-body tissue residue data are described by percentiles (5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles) for each of the target chemicals. The 

50th percentile is the median tissue concentration. Section 3.4 provides percentile tables by 

composite type for five target chemicals that occurred in a large percentage of the fish tissue 

samples. Appendix E provides percentile tables by composite type for all target chemicals 

detected in the fish samples.

Since the study design included analysis of fillets for predator composites and whole bodies 

for bottom-dweller composites, this study generated data relevant to both human and ecosystem health. In this report, however, predator results are highlighted because human 
The National Study of Chemical Residues in Lake Fish Tissue

Results

25

health screening values were readily available to interpret the fillet data for chemicals that 

occurred frequently in the edible tissue (Section 3.4). If available, wildlife criteria could be 

applied in the same manner to interpret the whole-body data from analysis of the bottomdweller composites.

Familiarity with certain technical information is critical for understanding the results. 

Section 3.1 provides a description of key technical elements and how they apply to the study 

data. Sections 3.2, 3.3, and 3.4 present the fish tissue results by respective composite type 

based on three levels of occurrence of target chemicals: not detected, rarely detected, and 

commonly detected. The five chemicals highlighted as commonly detected in Section 3.4 

are mercury, polychlorinated biphenyls (PCBs), dioxins and furans, DDT, and chlordane. 

According to EPA’s 2008 Biennial National Listing of Fish Advisories (USEPA 2009), these 

five chemicals accounted for 97% of the advisories in effect at the end of 2008. 

3.1 Technical Elements

3.1.1 Reporting Units

All fish tissue results are reported as wet weight concentrations. These concentrations are 

expressed as the mass of the chemical per unit of fish tissue mass. Each analytical method 

specifies the reporting units for a particular chemical or chemical group. Table 7 lists the 

reporting units for the seven EPA standard analytical methods used to generate fish tissue 

results.

Table 7. Reporting Units for EPA Standard Analytical Methods

EPA Method Chemical(s) Reporting Units

1631B Mercury ng/g (ppb)

1632A Arsenic μg/g (ppm)

1668A PCBs ng/kg (ppt)

1613B Dioxins and Furans ng/kg (ppt)

1656A Organochlorine Pesticides μg/kg (ppb)

1657A Organophosphate Pesticides μg/kg (ppb)

1625C Semivolatile Organic Chemicals μg/kg (ppb)

3.1.2 Detection and Quantitation Limits

The Code of Federal Regulations (CFR) provides a definition and description of the method 

detection limit (MDL) in 40 CFR, part 136. The MDL varies for different chemicals, matrices (e.g., water, sediment, or tissue), and analytical methods. Appendix B contains a table 

that lists the MDL for each of the target chemicals. Other factors can influence the MDL, 

such as increasing the sample size (e.g., the amount of tissue) used for analysis. In this study, 

EPA modified Method 1613B by increasing the volume of tissue analyzed from 10 grams 

to 100 grams to allow detection of dioxins and furans at levels ten times lower than those 

specified in the method.
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The National Study of Chemical Residues in Lake Fish Tissue

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The MDL is designed to provide a 99% level of confidence that when a chemical is reported 

as being present, it really is present. The opposite is not true, however. If a chemical is 

reported as not being present at the MDL level, there is a 50% possibility that the chemical 

is really present (i.e., the result is a false negative).

The minimum level of quantitation (ML) is the lowest concentration at which the analytical 

system gives a quantitative result. Generally speaking, the ML is approximately three times 

greater than the MDL, and it is comparable to the American Chemical Society’s Limit of 

Quantitation. The table in Appendix B lists the MLs for all of the target chemicals.

For this study, laboratories reported all positive results that met the method-specified criteria 

down to the MDL. They also applied a “J” flag to any results reported at or above the MDL 

(detection limit), but below the ML (quantitation limit). The “J” flag indicates that the 

chemical was present, but the reported value is an estimate of the true concentration since it 

was detected below the quantitation limit. Appendix F provides a breakdown by composite 

type and chemical of the concentrations that occurred below the MDL, between the MDL 

and ML (and inclusive of the MDL), and at or above the ML. The “J” flagged values were 

included in all analyses of the fish tissue data.

3.1.3 Total Toxicity Equivalency and Summed Chemicals

The tissue concentrations for dioxins and furans are reported as toxicity-weighted total 

concentrations. They are derived by multiplying an individual toxicity equivalency factor 

(TEF) by the concentrations of each of the seven dioxins and ten furans, then summing 

the 17 results. This sum is referred to as the total toxicity equivalency or total TEQ. EPA’s 

Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories, Volume I: 

Fish Sampling and Analysis, Third Edition (USEPA 2000d) includes a discussion of the 

method for estimating total TEQ, and it provides a list of the toxicity equivalency factors for 

the 17 dioxins and furans.

In addition to the 17 dioxins and furans, fish tissue samples were analyzed for multiple 

forms of other chemicals, such as PCBs, chlordane, DDT and endosulfan. Analysis of 

tissue samples for PCBs included all 209 congeners (individual PCB compounds), which 

produced 159 congener measurements due to co-elution of up to six individual congeners 

(Section 2.2.3). Results for the 12 coplanar (“dioxin-like”) PCBs were converted to toxic 

equivalents, added to toxicity-weighted concentrations for dioxins and furans, and reported 

as a total TEQ in accordance with EPA guidance (USEPA 2000d). Tissue analysis for the 

three organochlorine pesticides involved multiple isomers, including five for chlordane, 

six for DDT, and two for endosulfan. Results for these chemical groups are reported as 

individual congener or isomer concentrations and as summed concentrations for each group. 

In developing the summed concentrations, non-detected components of the chemical were 

assigned a value of zero for this report. The summed concentrations from the predator fillet 

results are compared to human health screening values published in Volume 2 of EPA’s 

Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories (USEPA 

2000e).
The National Study of Chemical Residues in Lake Fish Tissue

Results

27

3.1.4 Cumulative Distribution Functions

A cumulative distribution function (CDF) offers an approach to displaying statistical data 

that correlates the results to the sampled population. In technical terms, a CDF characterizes the probability distribution of a random variable (Zar 1999). For this study, the random 

variable is the concentration of a particular chemical in fish tissue. Each chemical and composite type has a unique probability distribution.

The probability distributions for fillet and whole-body fish tissue concentrations are presented 

by chemical and composite type as plots of chemical concentration (x-axis) versus the cumulative percentage of lakes (y-axis) (Section 3.4 and Appendix G). Every point on the plot is a 

mean tissue concentration measured for a fillet composite or a whole-body composite, and 

each of these points corresponds to a sampling site where the chemical was detected in the 

tissue composite. The maximum number of points for a CDF displaying predator (fillet) data 

is 486 because predator composites were collected from 486 of the 500 sampling locations. 

Similarly, the maximum number of points for a CDF presenting bottom-dweller (whole-body) 

data is 395 because bottom dwellers were only sampled from 395 of the 500 locations. The 

points are plotted in order of increasing tissue concentration. An important point of reference 

on the CDFs is the median, or the tissue concentration corresponding to 50% of the lakes. 

Many target chemicals did not have sufficient tissue data to develop a CDF with adequate 

resolution. The CDFs included in Appendix G represent chemicals that had published 

human health screening values and at least 50 data points (i.e., tissue concentrations above 

the MDL). Five chemicals or chemical groups met these criteria, including mercury, PCBs, 

dioxins and furans, DDT, and chlordane. Predator and bottom-dweller CDFs for these 

commonly-occurring chemicals are displayed and described in Section 3.4. Human health 

screening values are most commonly applicable to fillet data, not whole-body data; therefore, bottom-dweller (whole-body) CDFs do not include human health thresholds.

Each CDF contains a horizontal (x) axis for tissue concentrations and two vertical (y) axes. 

The left y-axis presents the cumulative percentage of lakes, and the right y-axis shows the 

corresponding number of lakes in the sampled population. The human health screening 

value appears on the predator CDFs as a dashed green line. The point of intersection of 

the human health screening concentration on the left y-axis indicates the point where the 

percentage of lakes is below this threshold. The intersection on the right y-axis provides an 

estimate of the number of lakes with tissue concentrations below the human health screening value. Subtracting these points of intersection from the maximum values on each y-axis 

(e.g., 100% for the left y-axis and 76,559 for the right y-axis on predator CDFs) will give 

the percentage of lakes and the corresponding number of lakes that exceed the human health 

screening value (Section 3.1.5). 

3.1.5 Human Health Screening Values

The human health screening value applied to predator results for mercury is EPA’s tissuebased water quality criterion published in January 2001 (USEPA 2001b). EPA has no other 

tissue-based water quality criteria available, so all other human health screening values 
28

The National Study of Chemical Residues in Lake Fish Tissue

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applied to predator results in this report are risk-based consumption limits published in 

EPA’s Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories, 

Volume 2: Risk Assessment and Fish Consumption Limits, Third Edition (USEPA 2000e). 

Section 3 of the guidance describes the methods and assumptions (e.g., body weight and 

acceptable risk level) used to derive the consumption limits. Section 4 of the guidance provides tables of risk-based consumption limits. The screening values include consumption 

limits for both carcinogenic and noncarcinogenic health effects. Following the recommendation in the guidance, this report uses the more conservative consumption limit as a screening 

value to account for both types of health effects.

The screening value for mercury in this report is EPA’s tissue-based water quality criterion 

of 0.3 ppm (or 300 ppb) (USEPA 2001b). Consistent with the recommendation issued by the 

Food and Drug Administration (FDA) and EPA for instances where no fish consumption 

advice is available, all other screening values in this report are based on consumption limits 

for four meals per month (or one meal per week). Specifically, the report screening values are 

the upper limit of the four-meal-per-month concentration range for the more conservative 

consumption limit where tissue concentrations are available for both cancer and noncancer 

health endpoints. Table 8 provides a list of the screening values (SVs) used to interpret 

predator results for this study.

Table 8. Human Health Screening Values (SV)a for Interpreting National Lake Fish Tissue 

Study Predator Results 

CHEMICAL VOL. 2

TABLE

HEALTH

ENDPOINT

SV FISH TISSUE

CONCENTRATION

UNITS

Mercury WQCb Noncancer 300 ppb

Arsenic (inorganic) 4-1 Cancer 0.016 ppm

PCBs 4-24 Cancer 12 ppb

Dioxins/Furans 4-25 Cancer 0.15 ppt

Chlordane 4-6 Cancer 67 ppb

DDT 4-7 Cancer 69 ppb

Dicofol 4-8 Noncancer 700 ppb

Dieldrin 4-9 Cancer 1.5 ppb

Endosulfan 4-10 Noncancer 14000 ppb

Endrin 4-11 Noncancer 700 ppb

Heptachlor epoxide 4-12 Cancer 2.6 ppb

Lindane (gamma BHC) 4-14 Cancer 18 ppb

Mirex 4-15 Noncancer 470 ppb

Toxaphene 4-16 Cancer 21 ppb

a Taken from EPA’s Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories, Volume 2: Risk 

Assessment and Fish Consumption Limits, Third Edition.

b Screening value for mercury is the tissue-based water quality criterion (WQC) published by EPA in January 2001 

(USEPA 2001b). 
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29

3.2 Chemicals Not Detected

In reporting the analytical results for this study, it is important to distinguish between detection and presence of a chemical in a fish tissue sample. As discussed in Section 3.1.2, estimates of fish tissue concentrations ranging from the MDL (method detection limit) to the 

ML (minimum level or quantitation limit) are reported as being present with a 99% level 

of confidence. However, if a chemical is reported as “not detected” at the MDL level, there 

is a 50% possibility that the chemical may be present. Therefore, results for chemicals not 

detected in the fish tissue samples are reported as less than the MDL rather than zero.

Forty-three of the 268 target chemicals were not detected in any of the fish samples collected 

during this study. Table 9 provides a list of these chemicals. No detections were reported for 

any of the nine organophosphate pesticides (e.g., chlorpyriphos and diazinon), for one of the 

209 PCB congeners, or for 16 of the 17 polycyclic aromatic hydrocarbons (PAHs) analyzed 

as semivolatile organic chemicals. Seventeen other semivolatile organic chemicals were not 

detected in the fish samples, including hexachlorobenzene, which was a priority chemical 

under EPA’s Persistent, Bioaccumulative, and Toxic Chemicals Initiative. 

The choice of methods determines detection limits that can be achieved for each chemical or 

chemical group. Methods with lower detection limits often involve greater costs. External 

Table 9. Chemicals Not Detected in Any Samples.

Category Chemical

PCBs PCB-161

Organophosphate 

Pesticides

Chlorpyrifos

Diazinon

Disulfoton

Disulfoton sulfone

Ethion

Ethyl parathion

Paraoxon

Terbufos

Terbufos sulfone

PAHs Acenaphthene

Acenaphthylene

Anthracene

Benzo(a)anthracene

Benzo(a)pyrene

Benzo(b)fluoranthene

Benzo(ghi)perylene

Benzo(j)fluoranthene

Benzo(k)fluoranthene

Chrysene

Dibenzo(a,h)anthracene

Fluoranthene

Fluorene

Indeno (1,2,3-cd) pyrene

Perylene

Phenanthrene

Other Semivolatile 

Organic Chemicals

1,2,4,5-Tetrachlorobenzene

1,2,4-Trichlorobenzene

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene

2,4,5-Trichlorophenol

2,4,6-Tris(1,1-dimethylethyl) phenol

3,3’-dichlorobenzidine

4,4’-Methylenebis (2-chloroaniline)

4-Bromophenyl phenyl ether

Diethylstilbestrol

Hexachlorobenzene

Hexachlorobutadiene

Nitrobenzene

Pentachlorobenzene

Pentachlorophenol

Tetrabromobisphenol A
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peer reviewers of the study design identified analytical methods with lower detection limits 

that were available for some of the semivolatile organic chemicals, including PAHs and 

Tetrabromobisphenol A (a chemical linked to endocrine disruption). EPA did not use these 

methods in the study due to resource constraints. However, applying methods with lower 

detection limits may have produced different results.

3.3 Rarely-detected Chemicals

Thirty-four target chemicals occurred infrequently in the fish tissue samples (excluding 

individual congeners or isomers of summed chemicals). Most of these chemicals were either 

organochlorine pesticides or semivolatile organic compounds. Tables 10 and 11 provide a 

list of these chemicals and their frequency of occurrence for predator samples and bottomdweller samples, respectively. The tables present frequency of occurrence for the chemical 

groups as a percentage of total sampling locations. These percentages are divided into four 

intervals for predator samples (<1%, 1–5%, 5–10%, 10–15%) and six intervals for bottomdweller samples (<1%, 1–5%, 5–10%, 10–15%, 15–20%, and 20–35%).

Thirty-two of the 34 rarely-detected chemicals occurred in the predator samples, including three forms of arsenic, 24 organochlorine pesticides, and five semivolatile organic 

compounds. Total inorganic arsenic and DMA (an organic arsenic compound) occurred 

in predator samples at less than 1% of the sampling sites, while MMA (another form of 

organic arsenic found only in predators) occurred at less than 5% of the sites. Twenty-two 

of the organochlorine pesticides were detected in predator samples at less than 10% of the 

sites, and eight of these pesticides were found at less than 1% of the sites. The two remaining pesticides, kepone and pentachloroanisole, were both detected at 12% of the sites. Three 

semivolatile organic compounds occurred in predator samples at less than 1% of the sites, 

including nonylphenol, pyrene, and a phthalate. Two other phthalates, bis(2-ethylhexyl) 

phthalate and di-n-butyl phthalate, were detected in predator samples at 1% and 7% of the 

sites, respectively.

Thirty-three of the 34 rarely-detected chemicals occurred in the bottom-dweller samples, 

including two forms of arsenic, 25 organochlorine pesticides, and six semivolatile organic 

compounds. Three of these chemicals were found only in bottom dwellers: naphthalene, 

phenol, and toxaphene. The other rarely-detected chemicals generally occurred more frequently in the bottom-dweller samples than in the predator samples. Total inorganic arsenic 

was detected in bottom-dweller samples at 9% of the sampling locations, and DMA was 

detected at less than 5% of the locations. Nineteen of the organochlorine pesticides were 

found in bottom dwellers at less than 10% of the locations, and three pesticides were present 

at 10% to 20% of the locations. The other three pesticides were detected in bottom-dweller 

samples at more than 20% of the sampling sites. Kepone occurred in bottom dwellers at 26% 

of the sites, while pentachloroanisole and trifluralin occurred at 27% and 32% of the sites, 

respectively. Four semivolatile organic chemicals were detected in bottom dwellers at less 

than 1% of the sites. Two remaining phthalates, bis (2-ethylhexy1) phthalate and di-n-butyl 

phthalate, were present in bottom-dweller samples at 3% and 7% of the sites, respectively.
The National Study of Chemical Residues in Lake Fish Tissue

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31

Table 10. Infrequent Chemical Occurrences in Predators (Fillets).

Chemical Grou

p

Perce

ntage of

Total Samplin

g Locatio

ns

<1% 1–5% 5–10% 10–15%

Metals Arsenic (total inorganic)

Dimethylarsinic acid (DMA)

Monomethylarsonic acid 

(MMA)

OrganochlorinePesticides

Endosulfan sulfateEndrinPendimethalinAldrinPermethrin, cisPermethrin, transHexachlorocyclohexane (BHC), 

alphaHexachlorocyclohexane (BHC), deltaDicofol Endosulfan (total) Ethalfluralin Heptachlor Heptachlor epoxide Isodrin Methoxychlor Mirex Octachlorostyren Dieldrin Hexachlorocyclohexane (BHC), beta- Hexachlorocyclohexane (BHC), gamma- Pentachloronitrobenzene Trifluralin Kepone (12%) Pentachloroanisole (12%)

Semivolatile Organic Chemicals

4-NonylphenolButyl benzyl phthalatePyrene

Bis (2-ethylhexyl) phthalate Di-n-butyl phthalate
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Table 11. Infrequent Chemical Occurrences in Bottom Dwellers (Whole Bodies).

Chemical Grou

p

Perce

ntage of

Total Samplin

g Locatio

ns

<1% 1–5% 5–10% 10–15% 15–20% 20–35%

Metals Dimethylarsinic acid 

(DMA)

Arsenic (total inorganic)

OrganochlorinePesticides

Toxaphene Aldrin

DicofolEndosulfan (total)Endosulfan sulfateEndrinHexachlorocyclohexane 

(BHC), alphaHexachlorocyclohexane (BHC), deltaIsodrin

MethoxychlorPendimethalinPermethrin, transOctachlorostyrene

HeptachlorHeptachlor epoxideHexachlorocyclohexane 

(BHC), betaHexachlorocyclohexane (BHC), gammaMirex

Permethrin, cisPentachloronitro- benzene Ethalfluralin Dieldrin Kepone (26%) Pentachloroanisole (27%) Trifluralin (32%)

Semivolatile Organic Chemicals

4-NonylphenolButyl benzyl 

phthalate

NaphthalenePhenol

Bis(2-ethylhexyl) 

phthalate

Di-n-butyl phthalate
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33

3.4 Commonly-detected Chemicals

3.4.1 Mercury

Mercury Overview

Mercury is widely distributed in the environment due to both natural and anthropogenic processes (USEPA 2000e). A major source of atmospheric mercury is the natural degassing of the 

earth’s crust; however, mercury releases are also attributable to anthropogenic sources such as 

mining and smelting, industrial processes, and the combustion of fossil fuels (ATSDR 1999). 

In the United States, primary sources of mercury emissions include coal-burning power 

plants, hazardous waste incineration, chlorine production, and mercury product breakage 

and spillage (USEPA 2001a). Mercury is generally released as elemental mercury or divalent 

mercury, but it may form mercury compounds through chemical processes in the air, soil, 

and water (ATSDR 1999). In the aquatic environment, microorganisms convert deposited 

(inorganic) mercury to toxic methylmercury that accumulates in fish, shellfish, and animals 

that eat fish. Nearly all fish and shellfish contain traces of mercury (USEPA 2005c), and 

methylmercury in fish is known to bind to amino acids in fish muscle tissue (USEPA 2000e). 

Generally, the amount of mercury in fish tissue increases with fish age and size (USEPA 

2000e). Mercury accumulation varies among fish species; however, piscivorous (fish-eating) 

species typically accumulate higher concentrations of mercury than non-piscivorous species. 

Mercury Fish Advisory Information

According to EPA’s 2008 Biennial National Listing of Fish Advisories (USEPA 2009), fish 

consumption advisories involving mercury account for 80% of all advisories in effect during 

2008. In 2008, a total of 16,808,032 lake acres (representing 40% of the Nation’s total lake 

acres) were under advisory for mercury in the United States. Mercury is highlighted in this 

report as a chemical of special interest because mercury advisories are widespread, and 

all fish samples collected for this study contained mercury at concentrations above the 

quantitation limit.

Mercury Analytical Notes and Human Health Thresholds

All National Lake Fish Tissue Study samples were analyzed for total mercury using 

Method 1631B. EPA’s Guidance for Assessing Chemical Contaminant Data for Use in Fish 

Advisories: Volume 1, Third Edition (USEPA 2000d) recommends monitoring for total 

mercury concentrations (rather than methylmercury) in state fish contaminant monitoring 

programs. EPA also recommends applying the conservative assumption that all mercury 

is present in fish tissue as methylmercury in order to be most protective of human health 

(USEPA 2006a). EPA’s tissue-based criterion for methylmercury was applied to predator 

(fillet) mercury results to identify the number (and percentage) of the sampled population 

of the Nation’s lakes that exceed this human health screening value. The Water Quality 

Criterion for the Protection of Human Health: Methylmercury (USEPA 2001b) regulations 

identified a fish tissue-based criterion of 0.3 mg methylmercury per kg (300 ppb) of fish 

tissue (wet weight). This represents the concentration in fish tissue that should not be 

exceeded based on a total consumption-weighted rate of 0.0175 kg of fish/day (assuming a 

human adult body weight default value of 70 kg and a reference dose of 0.0001 mg/kg-day).
34

The National Study of Chemical Residues in Lake Fish Tissue

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National Mercury Results

Mercury was detected in all predator and bottomdweller composite samples collected for this study at 

concentrations above the quantitation limit of 2 ng/g 

(ppb). Mercury tissue concentrations are reported as 

percentiles, including the median concentration (or 

50th percentile), for each composite type in Tables 

12 and 13. Concentrations in predators ranged from 

23 ppb to a maximum of 6,605 ppb, and the median 

concentration was 285 ppb (Figure 4). Mercury concentrations in bottom dwellers were generally lower 

than concentrations for predators. This is consistent 

with the findings of other studies in that piscivorous predator species typically accumulate 

higher concentrations of mercury than non-predators (USEPA 2000e). Concentrations in 

bottom-dweller composites ranged from 5 ppb to a maximum of 596 ppb, with a median 

concentration of 69 ppb. The mean mercury concentration was 352 ppb in predator composite samples and 96 ppb in bottom-dweller composite samples. National means were calculated for mercury only. A statistically valid mean could be calculated for mercury because 

the chemical was found in every sample above the quantitation limit. 

Table 12. Percentiles for Mercury Concentrations in Predator Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) 59.17 89.33 176.67 284.60 432.08 561.79 833.41

Lower Confidence 

Bound (95%) (ppb) 36.39 70.88 154.20 241.63 386.94 532.10 634.69

Upper Confidence 

Bound (95%) (ppb) 87.06 117.38 202.19 313.52 481.77 745.41 1018.68

Maximum Amount 

Detected 6605 ppb

Table 13. Percentiles for Mercury Concentrations in Bottom-dweller Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) 18.61 20.10 39.27 68.56 124.17 219.58 247.31

Lower Confidence 

Bound (95%) (ppb) 16.26 18.66 35.69 52.61 109.46 154.05 221.48

Upper Confidence 

Bound (95%) (ppb) 18.87 27.41 42.72 85.17 135.87 247.70 380.89

Maximum Amount 

Detected 596 ppb

Mercury Detections

l Mercury was detected in 100% 

of predator and bottom-dweller 

composite samples.

l The mean mercury 

concentration was 352 ppb in 

predator composite samples 

and 96 ppb in bottom-dweller 

composite samples.
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35

Figure 4. Box-and-whisker plot of mercury concentrations in predator and bottom-dweller 

samples. (The small box denotes the median or 50th percentile, the large box 

encloses the data between the 25th and 75th percentiles, and the whiskers indicate 

minimum and maximum values.)
36

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Prevalence of Mercury in the Sampled Population of Lakes

Cumulative distribution function (CDF) graphs (Figures 5 and 6) are used to illustrate the mercury concentrations that correspond to the percentage and 

number of the sampled population of lakes. For predator results, the human health screening value is overlaid on the CDF to identify the number and percentage 

of lakes with fish tissue mercury concentrations that 

are above or below the criterion. The percentage of 

lakes below this threshold can be read directly from 

the graph, while the percentage of lakes above this 

threshold can be derived by subtracting the percentage of lakes below the threshold from 

100%. The CDF (Figure 5) shows that edible portions (fillets) of predators in 48.8% of the 

sampled population of lakes had tissue concentrations that exceeded the 300 ppb human 

health screening value for mercury, representing a total of 36,422 lakes nationwide.

Figure 5. Cumulative distribution function of mercury concentrations in predator samples.

Prevalence of Mercury in 

Predators

l Mercury concentrations 

exceeded the human health 

screening value of 300 ppb 

in 36,422 of the Nation’s 

lakes (48.8% of the sampled 

population).
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Figure 6. Cumulative distribution function of mercury concentrations in bottom-dweller 

samples.

For more information on mercury, visit the following websites:

http://www.epa.gov/waterscience/fishadvice/advice.html

http://epa.gov/waterscience/fish/advisories/index.html

http://www.epa.gov/waterscience/fishadvice/mercupd.pdf

http://www.epa.gov/mercury/effects.htm

http://www.epa.gov/mercury/about.htm

http://www.atsdr.cdc.gov/tfacts46.html
38

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3.4.2 Total Polychlorinated Biphenyls (PCBs) 

PCB Overview

Polychlorinated biphenyls (PCBs) are manufactured chemicals that exist as mixtures of up 

to 209 individual compounds known as congeners. Although they were once utilized extensively by industry, the production and use of PCBs was banned in the United States in 1979 

because of evidence that they accumulate in the environment and can pose human health 

risks. Mixtures of various PCB congeners were developed for commercial use in the United 

States under the trade name Aroclor (ATSDR 2000). The Aroclors were labeled on the basis 

of their chlorine content, e.g., Aroclor 1254 has an average chlorine content of 54% by 

weight (USEPA 2000d). PCBs were never intended to be released into the environment, but 

rather were manufactured to be used in closed industrial systems. Their thermal stability, 

fire resistance, and solubility in organic compounds led to their use as coolants or lubricants. 

PCBs were included as insulating fluids in electrical transformers and capacitors, as fluids in 

vacuum pumps and compressors, and as hydraulic fluids.

Individual PCB congeners have widely varying potencies for producing a variety of adverse 

biological effects. PCB mixtures have been shown to cause adverse developmental effects 

in experimental animals (ATSDR 2000), and EPA has classified PCBs as probable human 

carcinogens (USEPA 2000e). PCBs can still be released into the air, soil, or water from 

illegal or improper disposal of industrial wastes, leaks from old electrical transformers or 

hazardous waste sites, and burning of some wastes in incinerators (ATSDR 2000). PCBs are 

extremely persistent in the environment, and they can be widely dispersed by atmospheric 

transport. After deposition on land, they bind strongly to soil particles. In water, some PCBs 

may remain dissolved, but most partition into bottom sediments and adhere to organic 

particles. PCBs bioaccumulate through the food chain, and humans can be exposed to 

elevated concentrations of PCBs through fish consumption.

PCB Fish Advisory Information

EPA’s 2008 Biennial National Listing of Fish Advisories (USEPA 2009) identified 1,025 fish 

consumption advisories for PCBs in 2008. Altogether, the PCB advisories affect 6,049,506 

lake acres (representing nearly 15% of the Nation’s total lake acres). PCBs are highlighted 

in this report as a chemical group of special interest because PCB advisories continue to 

be widespread, and because they were detected in 100% of all samples collected for this 

study.

PCB Analytical Notes and Human Health Thresholds

All National Lake Fish Tissue Study samples were analyzed for the full complement of 

209 congeners, which produced 159 congener measurements. These measurements included 

results for 126 individual congeners and 33 groups of 2 to 6 congeners. For a complete 

listing of the individual congeners and congener groups, refer to the target chemical list in 

Appendix B. PCBs were analyzed using Method 1668A, and results are presented as the 

sum of congeners following recommendations in EPA’s Guidance for Assessing Chemical 

Contaminant Data for Use in Fish Advisories: Volume 1, Third Edition (USEPA 2000d). 
The National Study of Chemical Residues in Lake Fish Tissue

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39

EPA recommends the reporting of total PCB concentrations (calculated as the sum of the 

concentrations of the congeners or homologues, i.e., co-eluting groups), since Aroclor 

analysis does not adequately represent bioconcentrated PCB mixtures found in fish tissue. 

An EPA risk-based tissue residue health endpoint for total PCBs was applied to predator 

(fillet) PCB results to identify the number (and percentage) of the sampled population of the 

Nation’s lakes that exceed this human health screening value. Table 4-24 in EPA’s Guidance 

for Assessing Chemical Contaminant Data for Use in Fish Advisories, Volume 2: Risk 

Assessment and Fish Consumption Limits, Third Edition (USEPA 2000e) lists a cancer 

health endpoint of 0.012 ppm (12 ppb) PCBs (wet weight) in fish tissue. This threshold 

represents the fish tissue concentration that should not be exceeded based on a total 

consumption-weighted rate of four 8-ounce (0.227 kg) fish meals per month (assuming a 

human adult body weight default value of 70 kg, a cancer slope factor of 2(mg/kg-d)-1, and a 

1 in 100,000 risk level) (USEPA 2000e).

National PCB Results

PCBs were detected in 100% of both predator and 

bottom-dweller composite samples collected for 

the National Lake Fish Tissue Study. PCB tissue 

concentrations are reported as percentiles, including 

the median concentration (or 50th percentile), for 

each composite type in Tables 14 and 15. Total PCB 

concentrations (sum of the congeners) in predators ranged from 0.061 ppb to 704.92 ppb, 

and the median concentration was 2.16 ppb (Figure 7). Concentrations in bottom dwellers 

were generally higher than levels detected in predators. This may be linked to the lipophilic 

nature of PCBs, which tend to accumulate in fatty tissues and organs (USEPA 2000e). 

Bottom-dweller results ranged from 0.598 ppb to 1,266.25 ppb, and the median PCB 

concentration in bottom-dweller composites was 13.90 ppb. [Results for individual PCB 

congeners are reported in Appendix E (percentiles) and Appendix F (occurrence)].

Table 14. Percentiles for PCB Concentrations in Predator Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) 0.35 0.49 1.00 2.16 8.13 18.17 33.16

Lower Confidence 

Bound (95%) (ppb) 0.19 0.35 0.89 1.65 5.26 16.51 23.43

Upper Confidence 

Bound (95%) (ppb) 0.41 0.64 1.20 2.62 10.30 30.10 59.60

Maximum Amount 

Detected 704.92 ppb

PCB Detections

l PCBs were detected in 100% of 

predator and bottom-dweller 

composite samples.
40

The National Study of Chemical Residues in Lake Fish Tissue

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Table 15. Percentiles for PCB Concentrations in Bottom-dweller Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) 1.58 2.31 5.15 13.90 70.87 130.79 198.32

Lower Confidence 

Bound (95%) (ppb) 1.50 1.58 3.87 9.05 41.95 113.70 133.83

Upper Confidence 

Bound (95%) (ppb) 2.20 3.24 5.75 20.29 92.07 196.97 435.57

Maximum Amount 

Detected 1266.25 ppb

Figure 7. Box-and-whisker plot of PCB (sum of congeners) concentrations in predator and 

bottom-dweller samples. (The small box denotes the median or 50th percentile, 

the large box encloses data between the 25th and 75th percentiles, and the 

whiskers indicate minimum and maximum values.)
The National Study of Chemical Residues in Lake Fish Tissue

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41

Prevalence of PCBs in the Sampled Population of Lakes

Cumulative distribution function (CDF) results for 

PCBs are presented in Figures 8 and 9. The CDF 

graphs depict PCB concentrations that correspond to 

the percentage and/or number of the sampled population of lakes. The human health screening value is 

plotted on the predator composite CDF to delineate 

between the number and percentage of lakes with 

fish tissue total PCB concentrations that are above or 

below the human health endpoint. The percentage of 

lakes below this threshold can be read directly from 

the graph, while the percentage of lakes above this threshold can be derived by subtracting 

the percentage of lakes below the threshold from 100%. Figure 8 indicates that edible portions (fillets) of predators in 16.8% of the sampled population of lakes had total PCB tissue 

concentrations that exceeded the 12 ppb human health screening value, representing a total 

of 12,886 lakes nationwide.

Figure 8. Cumulative distribution function of total PCB concentrations in predator samples.

Prevalence of PCBs in 

Predators

l Total PCB concentrations 

exceeded the human health 

screening value of 12 ppb 

in 12,886 of the Nation’s 

lakes (16.8% of the sampled 

population).
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Figure 9. Cumulative distribution function of total PCB concentrations in bottom-dweller 

samples.

For more information on PCBs, visit the following websites:

http://www.epa.gov/pbt/pubs/pcbs.htm

http://www.atsdr.cdc.gov/tfacts17.html
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3.4.3 Total Dioxins and Furans

Dioxin and Furan Overview

Dioxins and furans commonly refer to a group of synthetic organic chemicals that includes 

210 structurally-related chlorinated dibenzo-p-dioxins and chlorinated dibenzofurans 

(USEPA 2000e). The generic term dioxin is used here to refer to the aggregate of this 

group of compounds. Dioxins are not produced commercially, but rather are unintentional 

byproducts of combustion and certain industrial chemical processes. They may be formed 

during the chlorine bleaching process at pulp and paper mills, during chlorination by water 

treatment plants, or during the manufacture of certain organic chemicals. Dioxins can be 

released in emissions from solid waste and industrial incinerators (ATSDR 1998). Dioxin 

levels in the environment have been declining since the early 1970s; however, they are 

widely distributed in low concentrations, and current exposure levels still remain a concern 

(USEPA 2006b). Extremely low doses of the homologue 2,3,7,8-tetrachlorodibenzo-pdioxin (2,3,7,8-TCDD) have been found to elicit a wide range of toxic responses in animals 

(USEPA 2000d). Concerns over the health effects of 2,3,7,8-TCDD continue because of its 

persistence in the environment and its potential to bioaccumulate (USEPA 2000d). Dioxins 

have been characterized by EPA as likely human carcinogens, and are anticipated to increase 

the risk of cancer even at low background levels of exposure (USEPA 2006b). When released 

into the atmosphere, dioxins may be transported long distances. When discharged to surface 

water, some dioxins adhere to suspended solids and bottom sediments. Dioxins can be 

absorbed by fish through the gastrointestinal tract and skin, build up in fat and the liver, and 

bioaccumulate through the food chain (ATSDR 1998).

Dioxin and Furan Fish Advisory Information

EPA’s 2008 Biennial National Listing of Fish Advisories (USEPA 2009) lists 123 active 

fish consumption advisories involving dioxins in the United States. In 2008, a total of 

35,400 lake acres or 0.1% of the Nation’s total lake acres were under a dioxin advisory. 

The geographic extent of dioxin advisories is limited compared to that for the other four 

commonly-detected chemicals. This may be due in part to the relatively limited monitoring 

of dioxins throughout the country because of the high cost of analysis (USEPA 2007). 

Dioxins are highlighted in this report as a chemical group of special interest because 

a number of advisories are still in effect, and because they were detected in 89% of all 

samples collected for this study.

Dioxin and Furan Analytical Notes and Human Health Thresholds

All National Lake Fish Tissue Study samples were analyzed for 17 dioxins and furans using 

Method 1613B. Results were reported as toxicity-weighted total concentrations derived by 

multiplying results for each chemical by an individual toxicity equivalency factor (TEF), 

then summing the 17 results. This sum is referred to as the total toxicity equivalency or total 

TEQ (Section 3.1.3). EPA’s Guidance for Assessing Chemical Contaminant Data for Use in 

Fish Advisories, Volume 2: Risk Assessment and Fish Consumption Limits, Third Edition

(USEPA 2000e) recommends analyzing the 17 dioxins and furans together as a simplifying 
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and interim approach until further guidance is available on this chemical group. An EPA 

risk-based tissue residue health endpoint for dioxins and furans was applied to predator 

(fillet) dioxin and furan results to identify the number (and percent) of the sampled population of the Nation’s lakes that exceed this human health screening value. This same screening value was applied to results for the 12 coplanar PCB congeners, as recommended by 

EPA (USEPA 2000d). EPA’s Guidance for Assessing Chemical Contaminant Data for Use in 

Fish Advisories, Volume 2: Risk Assessment and Fish Consumption Limits, Third Edition

(USEPA 2000e) identified a cancer health endpoint of 0.15 ppt for dioxins and furans (TEQwet weight) in fish tissue. This represents the concentration in fish tissue that should not be 

exceeded based on a total consumption-weighted rate of four 8-ounce (0.227 kg) fish meals 

per month (assuming a human adult body weight default value of 70 kg, a cancer slope 

factor of 1.56 × 10-5 [mg/kg-d]-1, and a 1 in 100,000 risk level) (USEPA 2000e).

National Dioxin and Furan Results

Dioxins and furans were detected in 395 (of 486) 

predator and 393 (of 395) bottom-dweller samples 

collected for the National Lake Fish Tissue Study. 

Dioxin and furan tissue concentrations are reported 

as percentiles, including the median concentration (or 

50th percentile), for each composite type in Tables 16 

and 17. Concentrations in predators ranged from 

0.00002 ppt [TEQ] to 7.545 ppt [TEQ], and the 

median concentration was 0.006 ppt [TEQ] (Figure 10). Dioxin and furan concentrations 

in bottom-dwellers (Figure 10) were generally higher than concentrations for predators, 

which may be linked to their lipophilic nature. Dioxins tend to accumulate in fat and the 

liver (USEPA 2000e). Concentrations in bottom-dwellers ranged from 0.0008 ppt [TEQ] 

to a maximum of 23.814 ppt [TEQ], and the median concentration was 0.406 ppt [TEQ]. 

[Appendix E and Appendix F present percentiles and occurrence data for the 17 individual 

dioxins and furans.] 

Results for the 12 coplanar (“dioxin-like”) PCBs were derived by multiplying an individual 

toxicity equivalency factor (TEF) by the concentrations of each of the 12 congeners. Predator 

results ranged from 0.0003 ppt [TEQ] to 38.666 ppt [TEQ], with a median concentration 

of 0.030 ppt [TEQ]. Bottom dweller results ranged from 0.006 ppt [TEQ] to 20.018 ppt 

[TEQ], with a median concentration of 0.154 ppt [TEQ]. Results for Total TEQ, which 

includes dioxins and furans plus the 12 coplanar PCBs, ranged from 0.0003 ppt [TEQ] to 

46.211 ppt [TEQ] for predators, with a median concentration of 0.042 ppt [TEQ]. Total 

TEQ concentrations in bottom dwellers ranged from 0.011 ppt [TEQ] to 27.062 ppt [TEQ], 

with a median concentration of 0.677 ppt [TEQ]. [Appendix E and Appendix F present 

percentiles and occurrence data for the TEQ of the 12 coplanar PCBs and Total TEQ of 

dioxins and furans combined with the coplanar PCBs.] 

Dioxin and Furan 

Detections

l Dioxins and furans were 

detected in 81% of predator 

and 99% of bottom-dweller 

composite samples.
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Table 16. Percentiles for Dioxin and Furan Concentrations (D/F TEQ) in Predator Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppt) <MDL <MDL <MDL 0.006 0.05 0.11 0.32

Lower Confidence 

Bound (95%) (ppt) <MDL <MDL <MDL 0.004 0.03 0.09 0.14

Upper Confidence 

Bound (95%) (ppt) <MDL <MDL <MDL 0.008 0.07 0.20 0.70

Maximum Amount 

Detected 7.545 ppt

Table 17. Percentiles for Dioxin and Furan Concentrations (D/F TEQ) in Bottom-dweller 

Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppt) 0.020 0.06 0.16 0.41 1.07 1.77 2.01

Lower Confidence 

Bound (95%) (ppt) 0.005 0.02 0.13 0.33 0.68 1.49 1.93

Upper Confidence 

Bound (95%) (ppt) 0.057 0.11 0.22 0.52 1.35 2.00 2.84

Maximum Amount 

Detected 23.814 ppt

Table 18. Percentiles for Dioxin, Furan, and Coplanar PCB Concentrations (Total TEQ) in 

Predator Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppt) 0.004 0.006 0.013 0.042 0.14 0.51 1.24

Lower Confidence 

Bound (95%) (ppt) 0.002 0.004 0.012 0.035 0.11 0.27 0.87

Upper Confidence 

Bound (95%) (ppt) 0.006 0.009 0.018 0.077 0.19 1.16 2.20

Maximum Amount 

Detected 46.211 ppt
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Table 19. Percentiles for Dioxin, Furan, and Coplanar PCB Concentrations (Total TEQ) in 

Bottom-dweller Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppt) 0.073 0.108 0.291 0.677 2.89 5.30 5.83

Lower Confidence 

Bound (95%) (ppt) 0.036 0.068 0.195 0.490 2.33 4.59 5.61

Upper Confidence 

Bound (95%) (ppt) 0.082 0.157 0.362 1.273 4.00 5.83 9.59

Maximum Amount 

Detected 27.062 ppt

Figure 10. Box-and-whisker plot of total dioxin and furan concentrations in predator and 

bottom-dweller samples. (The small box denotes the median or 50th percentile, 

the large box encloses data between the 25th and 75th percentiles, and the 

whiskers indicate minimum and maximum values.)
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Prevalence of Dioxins and Furans in the Sampled Population of Lakes

Cumulative distribution functions (CDFs) (Figures 11 

and 12) are used to identify the dioxin and furan 

concentrations that correspond to the percentage 

and number of the sampled population of lakes. 

For predator results, the human health screening 

value is plotted on the CDF to identify the number 

and percentage of lakes with fish tissue total dioxin 

and furan concentrations that are above or below 

the screening value. The percentage of lakes below 

this threshold can be read directly from the graph, 

while the percentage of lakes above this threshold can be derived by subtracting the 

percentage of lakes below the threshold from 100%. Figure 11 shows that edible portions 

(fillets) of predators in 7.6% of the sampled population of lakes had tissue concentrations 

that exceeded the 0.15 ppt [TEQ] human health screening value for dioxins and furans, 

representing a total of 5,856 lakes nationwide.

Figure 11. Cumulative distribution function of total dioxin and furan concentrations in 

predator samples.

Prevalence of Dioxins and 

Furans in Predators

l Dioxin and furan concentrations 

exceeded the human health 

screening value of 0.15 ppt 

[TEQ] in 5856 of the Nation’s 

lakes (7.6% of the sampled 

population).
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Figure 12. Cumulative distribution function of total dioxin and furan concentrations in 

bottom-dweller samples.

For more information on dioxin and furans, visit the following websites:

http://www.epa.gov/pbt/pubs/dioxins.htm

http://www.atsdr.cdc.gov/tfacts104.html

http://www.atsdr.cdc.gov/tfacts32.html
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3.4.4 Total DDT

DDT Overview

DDT (dichlorodiphenyltrichloroethane) is an organochlorine pesticide that was commonly 

used to control insects in agricultural applications between the mid-1940s and the early 

1970s. Its use was banned in the United States in 1972, primarily due to its toxic effects on 

wildlife (ATSDR 2002). Limited use of DDT continues throughout the tropics, as a means of 

controlling insects that carry disease (e.g., malaria) (USEPA 2000e). Commercial DDT preparations often included the DDT metabolites DDE (dichlorodiphenyldichloroethylene) and 

DDD (dichlorodiphenyldichloroethane). As a result, fish, wildlife, and humans have been 

typically exposed to a mixture of DDT, DDE, and DDD. DDT continues to be ubiquitous 

in the environment due to its widespread use prior to 1972 and its relatively long half-life. 

It breaks down fairly rapidly in air, but it adheres strongly to soil where its half-life ranges 

from 2 to 15 years (depending upon soil type) (ATSDR 2002). DDT in soil can enter groundwater and surface waters, and once it reaches aquatic environments, it can build up in fatty 

tissues of fish, birds, and other animals (USEPA 2000e). DDT and its metabolites continue 

to persist in the environment, are known to bioaccumulate, and have been classified by EPA 

as probable human carcinogens (USEPA 2000d).

DDT Fish Advisory Information

Although the use of DDT has been banned since 1972, there were 76 advisories still in effect 

for DDT (and its degradation products, DDE and DDD) in 2008 (USEPA 2009). These advisories affect 876,520 lake acres and represent 2% of the Nation’s total lake acres. DDT is 

highlighted in this report as a chemical of special interest because DDT advisories are in 

effect in several areas of the country, and because it was detected in 87% of all samples 

collected for this study. 

DDT Analytical Notes and Human Health Thresholds

Fish, wildlife, and humans are typically exposed to a mixture of DDT, DDE, DDD, and 

their degradation and metabolic products. EPA recommends reporting total DDT fish tissue 

results, based on the sum of the 4,4'- and 2,4' isomers of DDT, DDE, and DDD (USEPA 

2000e). Fish samples for this study were analyzed for the 4,4'- and 2,4' isomers of DDT, 

DDE, and DDD using Method 1656A, and those values were summed to provide total DDT 

results for each sample. (Note that no data for 2,4' isomers of DDT, DDE, and DDD are 

available for fish samples collected during the first year of the study.) An EPA risk-based 

tissue residue health endpoint for total DDT was applied to predator (fillet) results to identify the number (and percent) of the sampled population of the Nation’s lakes that exceed 

this human health screening value. EPA’s Guidance for Assessing Chemical Contaminant 

Data for Use in Fish Advisories, Volume 2: Risk Assessment and Fish Consumption Limits, 

Third Edition (USEPA 2000e) identified a cancer health endpoint of 0.069 ppm (69 ppb) 

DDT (wet weight) in fish tissue. This represents the concentration in fish tissue that should 

not be exceeded based on a total consumption-weighted rate of four 8-ounce (0.227 kg) 

fish meals per month (assuming a human adult body weight default value of 70 kg, a cancer 

slope factor of 0.34 [mg/kg-d]-1, and a 1 in 100,000 risk level) (USEPA 2000e).
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National DDT Results

DDT was detected in 378 (of 486) predator and 388 

(of 395) bottom-dweller samples collected for the 

National Lake Fish Tissue Study. Total DDT tissue 

concentrations are reported as percentiles, including 

the median concentration (or 50th percentile), for 

each composite type in Tables 20 and 21. Total 

concentrations in predators ranged from 0.77 ppb 

to 1,481.4 ppb, and the median concentration was 1.47 ppb (Figure 13). Bottom-dweller 

values were generally higher than concentrations detected in predators. DDT and its analogs 

are stored in fat, liver, kidney, and brain tissue (USEPA 2000e), which may explain the 

tendency for higher values in bottom-dweller samples. Total DDT concentrations in bottomdwellers ranged from 0.82 ppb to 1,760.57 ppb, with a median concentration of 12.68 ppb. 

[Percentiles and occurrence data for individual DDT isomers are reported in Appendix E 

and Appendix F.] 

Table 20. Percentiles for Total DDT Concentrations in Predator Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) <MDL <MDL <MDL 1.47 6.95 19.68 30.57

Lower Confidence 

Bound (95%) (ppb) <MDL <MDL <MDL 1.29 3.51 15.20 22.05

Upper Confidence 

Bound (95%) (ppb) <MDL <MDL 0.85 2.30 11.48 24.31 70.21

Maximum Amount 

Detected 1481.40 ppb

Table 21. Percentiles for Total DDT Concentrations in Bottom-dweller Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) 1.08 1.82 4.23 12.68 35.35 153.92 218.63

Lower Confidence 

Bound (95%) (ppb) 0.92 1.30 2.72 8.79 30.03 84.15 158.39

Upper Confidence 

Bound (95%) (ppb) 1.37 2.18 5.33 18.80 57.02 218.67 414.77

Maximum Amount 

Detected 1760.57 ppb

DDT Detections

l DDT was detected in 78% of 

predator and 98% of bottomdweller composite samples.
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Figure 13. Box-and-whisker plot of total DDT concentrations in predator and bottomdweller samples. (The small box denotes the median or 50th percentile, the 

large box encloses data between the 25th and 75th percentiles, and the whiskers 

indicate minimum and maximum values.)
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Prevalence of DDT in the Sampled Population of Lakes

Figures 14 and 15 illustrate the DDT concentrations 

that correspond to the percentage and number of the 

sampled population of lakes. For predator results, 

the human health screening value is plotted on the 

CDF to identify the number and percentage of lakes 

with fish tissue total DDT concentrations that are 

above or below the screening value. The percentage of 

lakes below this threshold can be read directly from 

the graph, while the percentage of lakes above this 

threshold can be derived by subtracting the percentage of lakes below the threshold from 

100%. Figure 14 shows that edible portions (fillets) of predators in 1.7% of the sampled 

population of lakes had tissue concentrations that exceeded the 69 ppb human health 

screening value for DDT, representing a total of 1,329 lakes nationwide.

Figure 14. Cumulative distribution function of total DDT concentrations in predator 

samples.

Prevalence of DDT in 

Predators

l DDT concentrations exceeded 

the human health screening 

value of 69 ppb in 1329 of the 

Nation’s lakes (1.7% of the 

sampled population).
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Figure 15. Cumulative distribution function of total DDT concentrations in bottom-dweller 

samples.

For more information on DDT, visit the following websites:

http://www.epa.gov/pbt/pubs/ddt.htm

http://www.atsdr.cdc.gov/tfacts35.html
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3.4.5 Total Chlordane

Chlordane Overview

Chlordane is a multipurpose organochlorine insecticide that has been used extensively in 

home and agricultural applications in the United States for the control of termites and other 

insects (USEPA 2000d). It is a manufactured chemical and does not occur naturally in the 

environment. Chlordane was first introduced in 1947, but most chlordane uses were banned 

in 1978, and all uses were banned by EPA in 1998 due to human and wildlife exposure 

concerns (USEPA 2000b). Chlordane is known to be extremely lipid soluble, is moderately 

to highly toxic, and has been classified as a probable human carcinogen by EPA (IRIS 

1998). For the purposes of health advisory development, this organochorine insecticide is 

considered by EPA to be comprised of the sum of cis- and trans- isomers of chlordane, cisand trans- isomers of nonachlor, and oxychlordane (the major metabolite of chlordane). 

Most people in the United States have been exposed to low levels of chlordane due to its 

widespread use (USEPA 2006b). Chlordane can be found in soils surrounding structures 

where it was applied to control for termites, and it can be transported to soils and waters 

by atmospheric deposition. It can linger in soils for over 20 years following application or 

deposition (ATSDR 1994). In the aquatic environment, chlordane is bound to particles in the 

water column and in substrate sediments. It has been widely detected in freshwater fish (both 

predators and bottom-feeding species), estuarine and marine fish, and marine bivalves (e.g., 

clams) at concentrations of human health concern (USEPA 2000d). Because it has a long 

half-life and it is a bioaccumulative chemical, chlordane continues to be commonly detected 

in fish in the United States (USEPA 2000b). 

Chlordane Fish Advisory Information

According to EPA’s 2008 Biennial National Listing of Fish Advisories (USEPA 2009), there 

are 67 active fish consumption advisories involving chlordane in the United States. In 2008, 

a total of 842,913 lake acres (representing 2% of the Nation’s total lake acres) were under 

advisory for chlordane. Chlordane is highlighted in this report as a chemical of special 

interest because chlordane advisories remain relatively widespread, and because it was 

detected in 33% of all fish samples collected for this study.

Chlordane Analytical Notes and Human Health Thresholds

All National Lake Fish Tissue Study samples were analyzed for cis-chlordane, transchlordane, cis-nonachlor, trans-nonachlor, and oxychlordane using Method 1656A. Results 

for these five major degradation products of chlordane were summed to yield values for total 

chlordane (Section 3.1.3). EPA’s Guidance for Assessing Chemical Contaminant Data for 

Use in Fish Advisories, Volume 2: Risk Assessment and Fish Consumption Limits, Third 

Edition (USEPA 2000e) recommends monitoring for total chlordane concentrations for 

fish contaminant and health advisory monitoring. An EPA risk-based tissue residue health 

endpoint for total chlordane was applied to predator (fillet) chlordane results to identify 

the number (and percent) of the sampled population of the Nation’s lakes that exceed this 

human health screening value. EPA’s Guidance for Assessing Chemical Contaminant Data 

for Use in Fish Advisories, Volume 2: Risk Assessment and Fish Consumption Limits, 
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55

Third Edition (USEPA 2000e) identified a cancer health endpoint of 67 ppb chlordane (wet 

weight) in fish tissue. This represents the concentration in fish tissue that should not be 

exceeded based on a total consumption-weighted rate of four 8-ounce (0.227 kg) fish meals 

per month (assuming a human adult body weight default value of 70 kg, a cancer slope 

factor of 0.35 (mg/kg-d)-1, and a 1 in 100,000 risk level) (USEPA 2000e).

National Chlordane Results

Chlordane was detected in 96 (of 486) predator and 

197 (of 395) bottom-dweller samples. Total chlordane 

tissue concentrations are reported as percentiles, 

including the median concentration (or 50th percentile), 

for each composite type in Tables 22 and 23. Predator 

concentrations ranged from 0.59 ppb to 99.99 ppb, 

and the median concentration was less than the MDL for total chlordane (Figure 16). 

Bottom-dweller chlordane concentrations (Figure 16) were generally higher than levels 

detected in predators, which may be due to their tendency to partition to fatty tissues and 

organs (USEPA 2000e). Total concentrations in bottom-dwellers ranged from 0.50 ppb to 

377.98 ppb, with a median concentration of 1.65 ppb. [Percentiles and occurrence data for 

each chlordane compound are reported in Appendix E and Appendix F.]

Table 22. Percentiles for Total Chlordane Concentrations in Predator Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) <MDL <MDL <MDL <MDL <MDL 3.62 8.27

Lower Confidence 

Bound (95%) (ppb) <MDL <MDL <MDL <MDL <MDL 2.13 4.43

Upper Confidence 

Bound (95%) (ppb) <MDL <MDL <MDL <MDL <MDL 8.14 9.26

Maximum Amount 

Detected 99.99 ppb

Table 23. Percentiles for Total Chlordane Concentrations in Bottom-dweller Samples.

Percentile 5th 10th 25th 50th 75th 90th 95th

Concentration 

(ppb) <MDL <MDL <MDL 1.65 9.31 25.96 30.93

Lower Confidence 

Bound (95%) (ppb) <MDL <MDL <MDL <MDL 6.81 16.31 25.98

Upper Confidence 

Bound (95%) (ppb) <MDL <MDL <MDL 3.35 15.27 30.99 78.74

Maximum Amount 

Detected 377.98 ppb

Chlordane Detections

l Chlordane was detected in 20% 

of predator and 50% of bottomdweller composite samples.
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Figure 16. Box-and-whisker plot of total chlordane concentrations in predator and bottomdweller samples. (The small box denotes the median or 50th percentile, the 

large box encloses data between the 25th and 75th percentiles, and the whiskers 

indicate minimum and maximum values.)
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Prevalence of Chlordane in the Sampled Population of Lakes

Figures 17 and 18 are cumulative distribution 

function (CDF) graphs that illustrate the chlordane 

concentrations corresponding to the percentage (and 

number) of the sampled population of lakes. The 

human health screening value is plotted on the CDF 

for predators to delineate between those lakes with 

fish tissue total chlordane concentrations that are 

above the cancer health endpoint versus those that are 

below the endpoint. The percentage of lakes below 

this threshold can be read directly from the graph, while the percentage of lakes above this 

threshold can be derived by subtracting the percentage of lakes below the threshold from 

100%. Figure 17 shows that edible portions (fillets) of predators in 0.3% of the sampled 

population of lakes had fish tissue concentrations that exceeded the 67 ppb human health 

screening value for total chlordane, representing a total of 235 lakes nationwide.

Prevalence of Chlordane 

in Predators

l Chlordane concentrations 

exceeded the human health 

screening value of 67 ppb in 

235 of the Nation’s lakes (0.3% 

of the sampled population).

Figure 17. Cumulative distribution function of total chlordane concentrations in predator 

samples.
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Figure 18. Cumulative distribution function of total chlordane concentrations in bottomdweller samples.

For more information on chlordane, visit the following websites:

http://epa.gov/waterscience/fish/advisories/index.html

http://www.epa.gov/pbt/pubs/chlordane.htm

http://www.atsdr.cdc.gov/tfacts31.html
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 3.5 Sampling Variability

Field teams collected replicate samples of predators from 70 lakes and bottom dwellers from 

52 lakes (simultaneously with standard sample collection) to provide estimates of sampling 

variability. For this study, a replicate sample consisted of a second composite of fish containing the same species and number of fish and specimens with similar size ranges as the original (standard) sample. A representative set of lakes was selected for collection of replicate 

samples. Measuring sampling variability involved analyzing a standard composite sample 

and a replicate composite sample and comparing the results.

EPA applied a tiered approach to compare the results from standard and replicate samples. 

The first tier involved a simple comparison of agreement between the sample pairs using 

detection limits. The paired sample results were divided into three categories: sample results 

with both below detection, those with both above detection, and those with one below 

detection and one above detection. This was the only comparison possible for the large 

group of non-detected target chemicals (43 of the 268 total target chemicals). Appendix H 

provides the data for detection agreement between replicate sample pairs.

Comparisons of detections for the 70 predator and 52 bottom-dweller sample pairs showed 

perfect agreement in the results for mercury (i.e., mercury occurred in all sample pairs above 

detection). Sample pair comparisons also showed perfect agreement in detections for each of 

the 43 chemicals not detected in any of the fish samples, including organophosphate pesticides (i.e., all sample pair results were below detection). There was a high level of agreement 

between standard and replicate samples for arsenic detections, with 99–100% agreement 

for predator sample pairs and 88–100% agreement for bottom-dweller sample pairs. For the 

159 PCB congener results, 75% of the predator sample pairs and 80% of the bottom-dweller 

sample pairs showed 90–100% detection agreement. Detection results varied the most for 

dioxins and furans, ranging from 71–100% agreement for both the predator and bottomdweller sample pairs. For DDT and chlordane, differences are apparent in the level of agreement for detection between predator and bottom-dweller sample pairs. Predator detection 

agreement ranged from 87–100% for DDT and 94–100% for chlordane, while agreement in 

detections for bottom dwellers ranged from 75–100% for DDT and 88–96% for chlordane. 

The high level of agreement for detections of semivolatile organic chemicals (94–100% for 

both predator and bottom-dweller sample pairs) reflects the large number of non-detected 

chemicals in this group.

The second tier for estimating sampling variability involved comparisons of measured 

concentrations when both samples were above detection or when one sample (standard or 

replicate) was above detection and the other was below detection. In the first case, the two 

concentrations were compared directly. In the second case, the measured concentration was 

compared to the method detection limit. Appendix I contains the results for these comparisons. Differences between standard and replicate sample concentrations are summarized 

as minimum and maximum values and percentiles (10th, 25th, 50th, 75th, and 90th) for all 

detected target chemicals. 
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The National Study of Chemical Residues in Lake Fish Tissue

4.0 Conclusions and Recommendations

For the first time in its history, EPA has freshwater fish contamination data available to draw 

statistically valid conclusions about the occurrence of persistent, bioaccumulative, and toxic 

chemicals in lakes and reservoirs of the conterminous United States. Obtaining, analyzing, 

and reporting these data required an agency investment of over eight years to complete 

the National Lake Fish Tissue Study. To succeed, it also required the long-term support 

(about five years) of more than 50 state, tribal, and other federal agencies contributing 

in-kind services. Given the inherent challenges in conducting a national-scale environmental 

assessment, the conclusions in this report cover technical (Section 4.1) and programmatic 

(Section 4.2) aspects of the study. The final sections of the report provide information about 

data availability (Section 4.3) and discuss recommendations for future national monitoring 

of freshwater fish contamination (Section 4.4).

4.1 Chemical Occurrences

4.1.1 Mercury

Elevated mercury concentrations in fish are the leading cause of fish advisories. In 2008, 

43% of the total lake acres in the United States were under advisory for mercury. Results 

from the National Lake Fish Tissue Study confirm that mercury is widely distributed in lakes 

and reservoirs across the country. Study data show that mercury was detected at quantifiable levels (i.e., concentrations at or above the quantitation limit) in every fish sample collected from all 500 locations sampled for the study. Statistical analysis of the mercury data 

revealed that mercury concentrations in the predator samples occurred above the 300 ppb 

human health screening value for mercury at nearly half of the lakes in the sampled population. These elevated mercury concentrations in predators apply to more than 36,000 lakes 

in the lower 48 states. Overall, the results from this statistically-based study underscore the 

pervasive nature of mercury deposition on lakes and their surrounding watersheds in the 

conterminous United States.

4.1.2 PCBs

Although the U.S. banned the production and use of PCBs in 1979, study results show that 

PCBs are still widely distributed in the environment. Like mercury, PCBs were detected in 

100% of both the predator and bottom-dweller samples. However, PCBs occurred at elevated 

concentrations to a lesser extent than mercury. Total PCB concentrations exceeded the human 

health screening value of 12 ppb at about 17% of the lakes in the sampled population, which 

represents nearly 13,000 lakes in the lower 48 states. Results from individual PCB congeners 

are more difficult to interpret. Information about the relative toxicities of the individual 

congeners is incomplete, and no screening values exist for the individual congeners.
62

The National Study of Chemical Residues in Lake Fish Tissue

Conclusions and Recommendations

The set of PCB data for the National Lake Fish Tissue Study includes results for PCB congeners and Aroclors. However, only the PCB congeners are officially counted and listed as 

target chemicals (Table 4 and Appendix B). In addition, the discussion about PCB results 

(Section 3.4.2) is limited to the congener data. Nonetheless, EPA also obtained Aroclor data 

from the analytical method for organochlorine pesticides (Method 1656A). Results from 

the statistical analyses of the Aroclor data are provided in Appendix E (percentiles). These 

results may be useful for agencies that have historical Aroclor tissue data or for agencies that 

are continuing to use the Aroclor method for PCB analysis because it is more economical. In 

the past, most laboratories used Aroclor methods to report PCB concentrations because few 

laboratories had the capability or expertise to perform congener analyses. For the Aroclor 

analysis, the laboratories assumed that the distribution of PCB congeners and parent Aroclors in environmental samples was similar, but current data indicate that PCBs are more 

persistent, bioaccumulative, and toxic than the original Aroclor mixtures. Therefore, congener analysis should provide a more conservative and accurate determination of total PCB 

concentrations than Aroclor analysis. 

4.1.3 Dioxins and Furans

Even though dioxins and furans are widely dispersed in the environment, results from this 

study indicate that they were somewhat less prevalent in lake fish than PCBs. Since dioxins tend to accumulate in fat rather than in muscle tissue, there was a distinct difference in 

the number of dioxin and furan detections between predator and bottom-dweller samples. 

Dioxins and furans were detected in 99% of the bottom-dweller samples and in 81% of the 

predator samples. Higher concentrations of dioxins and furans occurred in the whole-body 

tissue of bottom dwellers than in the fillets of predators, confirming that these chemicals collect in fatty tissue. The median concentration of 0.41 ppt (total TEQ) for bottom dwellers 

was nearly two orders of magnitude higher than the predator median concentration of 0.006 

ppt (total TEQ). Total dioxin and furan concentrations in predator samples exceeded the 

0.15 ppt (TEQ) human health screening value at less than 10% of the lakes in the sampled 

population or about 5800 lakes. Detailed information about dioxin exposure and associated 

human health effects is available online through EPA’s dioxin reassessment (http://cfpub.

epa.gov/ncea/). 

4.1.4 DDT and Chlordane

During the 1970s and 1980s, the U.S. banned the manufacture and use of most of the 

organochlorine pesticides included in the study. The low percentages of detections for 

the majority of these pesticides suggest that they are being effectively sequestered in lake 

environments. Two notable exceptions are DDT and chlordane. For this study, total DDT 

was more prevalent in the fish tissue than total chlordane. DDT was detected in 98% of the 

bottom-dweller samples and 78% of the predator samples, while chlordane was detected 

in 50% of the bottom-dweller samples and 20% of the predator samples. Like PCBs and 

dioxins and furans, DDT and chlordane had higher concentrations in the whole-body tissue 

of the bottom dwellers than in the predator fillets. However, the differences in the median 

concentrations between composite types for total DDT were less than an order of magnitude. 
The National Study of Chemical Residues in Lake Fish Tissue

Conclusions and Recommendations

63

Total concentrations of DDT and chlordane rarely exceeded their respective human health 

screening values of 69 ppb and 67 ppb. Concentrations of total DDT in predator samples 

exceeded the screening value at less than 2% of the lakes in the sampled population (about 

1300 lakes). Total chlordane concentrations in predator samples occurred above the screening 

value at less than 1% of the lakes in the sampled population (about 230 lakes). These results 

suggest a tendency toward declining concentrations for both DDT and chlordane.

4.2 Lessons Learned

Environmental monitoring on a national scale is a formidable challenge. EPA’s experience 

in conducting the National Lake Fish Tissue Study revealed that certain factors were crucial 

in successfully meeting this challenge. Foremost among these were broad cooperation, careful planning, and meticulous attention to detail in addressing the technical and logistical 

requirements of the study. More specifically, the three most critical factors that contributed 

to the success of this study included:

n Obtaining voluntary commitments and maintaining the support of a large network of 

partners among states, tribes, and other federal agencies,

n Allowing two years to plan the study design and mobilize for national-scale 

implementation of the study, and

n Establishing and maintaining a high degree of quality assurance/quality control to 

develop scientifically-defensible data.

4.2.1 Importance of Partnerships

A study of this magnitude cannot be conducted effectively in isolation. Instead, it requires 

the involvement of a large group of experts that have the knowledge and experience necessary to plan and implement the study on the local level. During workshops held around the 

country, EPA sought the participation of states, tribes, and other federal agencies to plan 

the study and provide long-term support for lake reconnaissance and fish collection. These 

workshops allowed EPA’s study management team to meet scientists from states, tribes, and 

various federal agencies, and to present study-specific information for evaluating lakes and 

collecting fish samples. It also allowed EPA to build a national network of partners that 

consisted of 47 states, three tribes, and two other federal agencies. These partnerships were 

crucial to the technical and financial success of the study. Completing the fish tissue analysis required 80% of the resources EPA allocated for the study. The in-kind contributions of 

partner agencies made fish collection for this study possible.

Maintaining voluntary participation in the National Lake Fish Tissue Study over the five-year 

period for lake reconnaissance and fish collection required some EPA actions or commitments 

in return. To allow greater participation in the study, EPA identified where flexibility 

was possible in the sampling design. Examples include allowing states to sample lakes in 

different years than they were scheduled in the study design and extending the field sampling 

season to provide more time for participants to complete fish collection. EPA’s commitment 
64

The National Study of Chemical Residues in Lake Fish Tissue

Conclusions and Recommendations

to simplifying procedures to reduce the burden on partner agencies also facilitated their 

continued participation. Finally, EPA’s agreement to distribute the fish tissue data to states 

and other participants on an annual basis for four years maintained their interest in the study.

4.2.2 Adequate Time for Planning and Mobilizing

Allowing adequate time for planning and organizing project logistics was vital to the success 

of this study. Too often schedules for project planning are compressed to a point where there 

is insufficient time to adequately explore design options or to access the full range of technical expertise available to support planning efforts. Project schedules also generally shortchange the time allowed for organizing project logistics. EPA management recognized how 

critical these study components were by providing budgetary support for one year of planning and an additional year for mobilizing. For planning, this made it possible to carefully 

consider all the elements of the study design (e.g., lake selection process and target chemical selection), to involve technical experts around the country in a study design workshop, 

and to conduct peer review of the study design. The additional year for mobilizing allowed 

EPA to establish a full national network of effective partnerships, to provide orientation and 

training for partners during workshops held in the ten EPA Regions over a period of ten 

months, to complete mapping and reconnaissance of 900 lakes, and to conduct pilot sampling in ten states to test project logistics prior to full-scale implementation of the study.

4.2.3 Commitment to Rigorous QA/QC

The National Lake Fish Tissue Study set a high QA/QC standard for scientific studies conducted by EPA. From the study’s inception, QA/QC activities became an integral part of 

all program operations. The national study management team developed an unprecedented 

number of quality assurance project plans (three) to thoroughly document all QA/QC procedures for fish sample collection (USEPA 2000a), fish tissue preparation and analysis (USEPA 

2000b), and statistical analysis of the study data (USEPA 2005a). Documenting all studyspecific procedures was crucial for establishing consistency among participants in field and 

laboratory operations across the country. Making a serious commitment to follow these 

procedures was critical for maintaining this consistency. EPA estimates about one-third of 

the combined efforts of agency staff, support contractors, and voluntary participants were 

devoted directly to QA/QC activities. This level of investment in QA/QC paid important 

dividends as evidenced by the fact that EPA did not lose a single fish sample during the four 

years of field sampling.

 4.3 Data Availability

EPA released the four years of National Lake Fish Tissue Study data to the public in October 2005. These data are available on CDs at no charge. The CDs contain field sampling 

information and analytical results (raw data) for fish samples collected at all 500 sampling 

locations, a data dictionary that defines each of the fields in the data files, and a report that 

summarizes analysis of the fish samples and results of the data quality review. Instructions 

for obtaining the study data are posted on the Internet at http://www.epa.gov/waterscience/

fishstudy/.
The National Study of Chemical Residues in Lake Fish Tissue

Conclusions and Recommendations

65

4.4 Future Monitoring 

The full complement of data from this study defines a national baseline of fish contamination in lakes and reservoirs of the lower 48 states. Future monitoring will be necessary to 

determine trends in occurrence of the target chemicals in lake fish and to track changes in 

concentrations of PBT chemicals in freshwater fish in response to pollution control activities. 

EPA’s PBT Monitoring Strategy identifies the National Lake Fish Tissue Study as an agency 

monitoring effort that should continue in the future. 

With the completion of this study, EPA recognizes the importance of conducting further 

studies to obtain representative chemical residue data for fish in other surface waters, to 

investigate the occurrence of contaminants of emerging concern (CECs) in fish tissue, and to 

generate data that define temporal trends in fish contaminant concentrations. The following 

future fish tissue monitoring activities would enhance the Agency’s current fish assessment 

program:

n Analysis of archived tissue from the National Lake Fish Tissue Study to investigate the 

occurrence of CECs in lake fish

n Analytical method development to expand the suite of methods available for 

quantifying concentrations of CECs in fish tissue

n Development of trend data for priority chemicals by repeating the National Lake Fish 

Tissue Study or a similar statistically-designed national study of lakes at an appropriate 

fixed interval (e.g., 5 or 10 years)

n Assessment of fish contamination in other surface waters, such as the fish tissue 

indicator work currently being conducted under EPA’s National Rivers and Streams 

Assessment.

Since national-scale studies are resource intensive, collaborative efforts similar to the support EPA received for the National Lake Fish Tissue Study would be necessary to implement 

the last two recommendations. Agency budget commitments over multiple years would also 

be necessary to fund these recommendations.
66

The National Study of Chemical Residues in Lake Fish Tissue

Conclusions and Recommendations
67

The National Study of Chemical Residues in Lake Fish Tissue

5.0 References

Agency for Toxic Substances and Disease Registry (ATSDR). 1999. Toxicological Profile for 

Mercury. Atlanta, GA: U.S. Department of Health and Human Services, Public Health 

Service. http://www.atsdr.cdc.gov/toxprofiles/tp46.pdf

Agency for Toxic Substances and Disease Registry (ATSDR). 2002. Toxicological Profile 

for DDT/DDE/DDD (Update). Atlanta, GA: U.S. Department of Health and Human 

Services, Public Health Service. http://www.atsdr.cdc.gov/toxprofiles/tp35.pdf

Agency for Toxic Substances and Disease Registry (ATSDR). 1998. Toxicological Profile for 

Chlorinated Dibenzo-p-dioxins (CDDs). Atlanta, GA: U.S. Department of Health and 

Human Services, Public Health Service. 

http://www.atsdr.cdc.gov/toxprofiles/tp104.pdf

Agency for Toxic Substances and Disease Registry (ATSDR). 2000. Toxicological Profile for 

Polychlorinated Biphenyls. Atlanta, Georgia: U.S. Department of Health and Human 

Services, Public Health Service. http://www.atsdr.cdc.gov/toxprofiles/tp17.pdf

Agency for Toxic Substances and Disease Registry (ATSDR). 1994. Toxicological Profile 

for Chlordane. Atlanta, GA: U.S. Department of Health and Human Services, Public 

Health Service. http://www.atsdr.cdc.gov/toxprofiles/tp31.pdf

Diaz-Ramos, S., D.L. Stevens, Jr., and A.R. Olsen. 1996. EMAP Statistics Methods Manual. 

EPA/620/R-96/XXX. Corvallis, OR: U.S. Environmental Protection Agency, Office 

of Research and Development, National Health and Environmental Effects Research 

Laboratory. http://www.epa.gov/nheerl/arm/documents/intro.pdf

Integrated Risk Information System (IRIS). 1998. U.S. Environmental Protection Agency, 

Washington, DC. http://www.epa.gov/iris

National Oceanic and Atmospheric Administration (NOAA). 1993. Sampling and Analytical 

Methods of the National Status and Trends Program-National Benthic Surveillance and 

Mussel Watch Projects 1984-1992. NOAA Technical Memorandum NOS ORCA 71. 

July, 1993. 

http://ccma.nos.noaa.gov/stressors/pollution/nsandt/bs_details.html

Olsen, A.R., B.D. Snyder, L.L. Stahl, and J.L. Pitt. 2009. Survey design for lakes and 

reservoirs in the United States to assess contaminants in fish tissue. Environmental 

Monitoring and Assessment 150:91-100.
68

The National Study of Chemical Residues in Lake Fish Tissue

References

Olsen, A.R., D.L. Stevens, Jr., and D. White. 1998. Application of global grids in 

environmental sampling. Computing Science and Statistics 30:279-284.

Stahl, L.L., B.D. Snyder, A.R. Olsen, and J.L. Pitt. 2009. Contaminants in fish tissue from 

US lakes and reservoirs: a national probabilistic study. Environmental Monitoring and 

Assessment 150:3-19.

Stevens, D.L. and A.R. Olsen. 2003. Variance estimation for spatially balanced samples of 

environmental resources. EnvironMetrics 14:593-610. 

http://www.epa.gov/nheerl/arm/documents/nbh.var.environmetrics.pdf

Stevens, D.L. and A.R. Olsen. 2004. Spatially balanced sampling of natural resources. 

Journal of the American Statistical Association 99:262-278. 

http://www.epa.gov/nheerl/arm/documents/grts_asa.pdf

Thompson, S. 1992. Sampling. John Wiley and Sons, New York, NY.

U.S. Environmental Protection Agency (USEPA). 1992. National Study of Chemical Residues 

in Fish. U.S. Environmental Protection Agency, Office of Science and Technology, 

Washington, D.C. EPA-823-R-92-008a. 

http://www.epa.gov/waterscience/library/fish/residuevol1.pdf

U.S. Environmental Protection Agency (USEPA). 1995. Guidance for Assessing Chemical 

Contaminant Data for Use in Fish Advisories. Volume 1: Fish Sampling and Analysis. 

Second Edition. U.S. Environmental Protection Agency, Office of Water, Washington, 

D.C. EPA-823-R-95-007. 

U.S. Environmental Protection Agency (USEPA). 1997. Guidance for Assessing Chemical 

Contaminant Data for Use in Fish Advisories. Volume 2: Risk Assessment and Fish 

Consumption Limits. Second Edition. U.S. Environmental Protection Agency, Office of 

Water, Washington, D.C. EPA-823-B-97-009. 

U.S. Environmental Protection Agency (USEPA). 1998. A Multimedia Strategy for Priority 

Persistent, Bioaccumulative, and Toxic (PBT) Pollutants [DRAFT]. 

http://www.epa.gov/pbt/pubs/pbtstrat.htm

U.S. Environmental Protection Agency (USEPA). 1999. National Study of Chemical Residues 

in Lake Fish Tissue: Study Design. U.S. Environmental Protection Agency, Office of 

Science and Technology, Washington, D.C. EPA-823-R-09-005.

http://www.epa.gov/waterscience/fishstudy/

U.S. Environmental Protection Agency (USEPA). 2000a. Quality Assurance Project Plan 

for Sample Collection Activities for a National Study of Chemical Residues in Lake 

Fish Tissue. U.S. Environmental Protection Agency, Office of Science and Technology, 

Washington, D.C. EPA-823-R-02-005. 

http://www.epa.gov/waterscience/fishstudy/
The National Study of Chemical Residues in Lake Fish Tissue

References

69

U.S. Environmental Protection Agency (USEPA). 2000b. Quality Assurance Project Plan 

for Analytical Control and Assessment Activities in the National Study of Chemical 

Residues in Lake Fish Tissue. U.S. Environmental Protection Agency, Office of Science 

and Technology, Washington, D.C. EPA-823-R-02-006. 

http://www.epa.gov/waterscience/fishstudy/

U.S. Environmental Protection Agency (USEPA). 2000c. Field Sampling Plan for the 

National Study of Chemical Residues in Lake Fish Tissue. U.S. Environmental 

Protection Agency, Office of Science and Technology, Washington, D.C. 

EPA-823-R-02-004. http://www.epa.gov/waterscience/fishstudy/

U.S. Environmental Protection Agency (USEPA). 2000d. Guidance for Assessing Chemical 

Contaminant Data for Use in Fish Advisories, Volume 1: Fish Sampling and Analysis, 

Third Edition. U.S. Environmental Protection Agency, Office of Water, Washington, 

D.C. EPA-823-B-00-007. 

http://www.epa.gov/waterscience/fish/advice/volume1/index.html

U.S. Environmental Protection Agency (USEPA). 2000e. Guidance for Assessing Chemical 

Contaminant Data for Use in Fish Advisories, Volume 2: Risk Assessment and Fish 

Consumption Limits, Third Edition. U.S. Environmental Protection Agency, Office of 

Science and Technology, Office of Water, Washington, D.C. EPA-823-B-00-008. 

http://www.epa.gov/waterscience/fish/advice/volume2/index.html

U.S. Environmental Protection Agency. 2001a. Mercury Update: Impact on Fish Advisories, 

Fact Sheet. U.S. Environmental Protection Agency, Office of Science and Technology, 

Office of Water, Washington, D.C. EPA-823-F-01-011. 

http://www.epa.gov/waterscience/fish/advice/mercupd.pdf

U.S. Environmental Protection Agency (USEPA). 2001b. Water Quality Criterion for the 

Protection of Human Health: Methylmercury. U.S. Environmental Protection Agency 

Washington, Office of Science and Technology, Office of Water, D.C. EPA-823-R-01-001. 

http://www.epa.gov/waterscience/criteria/methylmercury/pdf/mercury-criterion.pdf

U.S. Environmental Protection Agency (USEPA). 2005a. Quality Assurance Project Plan 

for Data Analysis Activities for the National Study of Chemical Residues in Lake Fish 

Tissue. U.S. Environmental Protection Agency, Office of Water, Washington, D.C. 

EPA-823-R-09-008. http://www.epa.gov/waterscience/fishstudy/

U.S. Environmental Protection Agency (USEPA). 2005b. Quality Assurance Report for the 

National Study of Chemical Residues in Lake Fish Tissue: Analytical Data for Years 1 

through 4. U.S. Environmental Protection Agency, Office of Water, Washington, D.C. 

EPA-823-R-05-005. http://www.epa.gov/waterscience/fishstudy/
70

The National Study of Chemical Residues in Lake Fish Tissue

References

U.S. Environmental Protection Agency (USEPA). 2006a. Draft Guidance for Implementing 

the January 2001 Methylmercury Water Quality Criterion. EPA-823-B-04-001. 

U.S. Environmental Protection Agency, Office of Water, Washington, D.C.

http://www.epa.gov/waterscience/criteria/methylmercury/pdf/guidance-draft.pdf

U.S. Environmental Protection Agency (USEPA). 2006b. Website - Persistent 

Bioaccumulative and Toxic (PBT) Chemical Program. 

http://www.epa.gov/pbt/pubs/cheminfo.htm

U.S. Environmental Protection Agency (USEPA). 2007. 2005/2006 National Listing of 

Fish Advisories Fact Sheet. U.S. Environmental Protection Agency, Office of Water, 

Washington, D.C. EPA-823-F-07-003. 

http://www.epa.gov/waterscience/fish/advisories/2006/tech.html

U.S. Environmental Protection Agency (USEPA). 2009. 2008 Biennial National Listing of 

Fish Advisories Fact Sheet. U.S. Environmental Protection Agency, Office of Water, 

Washington, D.C. EPA-823-F-09-007. 

http://www.epa.gov/waterscience/fish/advisories/tech2008.html

Zar, J.H. 1999. Biostatistical Analysis, Fourth Edition.  Prentice Hall, Inc., New Jersey.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A

National Lake Fish Tissue Study 

Sampling Locations

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-1

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

ALA

BAMA: 16 Lakes

AL Bankhead Reservoir Walker 0272 R 2003 33 37 17.76 87 12 11.52 1346.43AL Candles Lake Talladega 1497 4 2003 33 10 9.84 86 23 45.24 25.75

AL Choccolocco Lake Calhoun 1436 4 2003 33 36 47.52 85 59 37.68 6.97AL Clark’s Lake Russell 0560 2 2001 32 26 55.32 85 8 22.56 2.68

AL Jones Bluff Lake Lowndes 1072 3 2002 32 23 20.4 86 45 8.64 5063AL Lake Martin Tallapoosa 0236 R 2003 33 26 27.96 85 34 42.456 15783

AL Lewis Smith Lake Cullman/Walker/

Winston

0136 1 2000 34 4 51.24 87 7 55.2 8793.13

AL Payne Lake Hale 0947 3 2002 32 53 10.68 87 26 34.08 46.02

AL Pine Lake Houston 0622 2 2001 31 9 14.04 85 19 28.2 3.25

AL Unnamed lake Walker 0022 1 2000 33 56 55.32 87 19 53.4 4.37AL Unnamed lake Monroe 0923 3 2002 31 26 51 87 17 45.96 1.87AL Unnamed lake Marshall 0961 3 2002 34 7 22.44 86 17 52.08 3.37

AL Walter F. George 

Reservoir

Henry/Barbour 0072 1 2000 31 56 3.84 85 5 48.84 15281.91

AL Wheeler Lake Lauderdale 0161 1 2000 34 39 49.932 87 2 23.208 27143

AL William “Bill” 

Dannelly Reservoir

Wilcox 0197 1 2000 32 5 53.88 87 22 56.28 4738.41

AL Wilson Reservoir Colbert 0311 R 2003 34 49 27.084 87 30 14.328 6272.6

ARIZ

O

N

A: 3 Lakes

AZ Apache Lake Maricopa 0045 1 2000 33 35 15.36 111 17 32.28 888.11AZ Lake Havasu Mohave 1520 4 2002 34 30 3.24 114 21 56.52 7223

AZ Lake Mohave Mohave 1020 3 2001 35 27 14.04 114 38 10.32 10446.12

ARKANS

AS: 11 Lakes

AR Beaver Reservoir Benton 1493 4 2002 36 22 1.20 93 56 58.56 8310.84

AR Greers Ferry Lake Cleburne 0571 2 2000 35 33 39.60 92 9 47.16 4803AR Horseshoe Lake Crittenden 1522 4 2001 34 55 50.16 90 20 13.20 872.26
A-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

AR Lake Dardanelle Logan 0247 R 2003 35 21 7.92 93 24 21.6 12640.98

AR Lake DeGray Clark 1449 4 2002 34 15 25.56 93 14 14.64 4575.86

AR Lake Ouachita Garland 1371 4 2002 34 37 0.84 93 23 22.20 15815.64

AR Lake Terkington Arkansas 1396 4 2002 34 27 58.68 91 23 35.88 23.57

AR Millwood Lake Little River 1398 4 2002 33 45 2.16 94 0 14.40 9667.69

AR Norfolk Lake Baxter 0143 1 1999 36 24 22.68 92 14 31.20 7546.18

AR Ozark City Lake Franklin 0497 2 2000 35 31 54.84 93 49 57.00 166.23AR ReReg Lake Clark 0623 2 2000 34 11 4.92 93 6 13.32 151.71

C

ALIFORNI

A: 18 Lakes

CA Claire Engle 

Reservoir

Trinity 1426 4 2003 40 53 42.36 122 46 10.56 6757.19

CA Clear Lake Lake 0126 1 2000 39 1 35.76 122 46 13.8 15956.2

CA Crag Lake El Dorado 1026 3 2002 38 59 27.96 120 9 18.36 8.38

CA El Capitan Reservoir San Diego 0468 2 2002 32 54 44.64 116 46 51.6 589.97CA Finnon Reservoir El Dorado 1526 4 2003 38 47 53.52 120 44 54.6 8.58

CA Guadalupe Reservoir Santa Clara 0303 R 2003 37 11 33 121 52 21.72 25.64

CA Jewelry Lake Tuolumne 0027 1 2001 38 9 45.72 119 46 52.32 2.61

CA Lake Oroville Butte 0151 1 2001 39 34 47.64 121 21 35.64 1730.03

CA Lake Thomas Edison Fresno 0977 3 2003 37 22 46.92 118 58 39.36 755.47

CA Little Grass Valley 

Reservoir

Plumas 0301 R 2003 39 43 44.4 120 59 36.6 564.03

CA Meadow Lake Nevada 1351 4 2003 39 24 41.04 120 29 34.08 89.41

CA New Melones 

Reservoir

Calaveras 0227 R 2003 37 59 30.84 120 30 26.64 726.39

CA Pete’s Valley 

Reservoir

Lassen 0077 1 2003 40 32 40.56 120 26 56.04 10.86

CA Pine Flat Reservoir Fresno 0002 1 2001 36 52 28.92 119 14 5.64 2336.88
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-3

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

CA San Leandro 

Reservoir

Alameda 0051 1 2002 37 47 9.96 122 6 58.68 309.21

CA San Luis Reservoir Merced 0503 2 2002 37 2 38.04 121 7 39 5214.08

CA Shasta Lake Shasta 0476 2 2002 40 49 31.08 122 23 51 5467.73

CA Woodward 

Reservoir

Stanislaus 1002 3 2002 37 51 10.44 120 50 58.56 718.84

C

OLORA

D

O: 8 Lakes

CO Cherry Creek 

Reservoir

Arapahoe 1569 4 2000 39 38 22.92 104 51 15.48 347.28

CO Fuchs Reservoir Rio Grande 0969 3 2001 37 28 23.16 106 31 1.92 6.1

CO Left Hand Valley Boulder 0228 R 2003 40 5 49.92 105 15 56.88 45.82

CO Stalker Lake Yuma 0469 2 2001 40 5 7.44 102 16 34.68 6.63

CO Trujillo Meadows 

Reservoir

Conejos 0319 R 2003 37 3 2.88 106 27 9 29.16

CO Turk’s Pond Baca 0019 1 2000 37 29 10.32 102 22 56.28 22.13

CO Williams Fork 

Reservoir

Grand 0552 2 2001 40 1 3.72 106 12 22.68 546.12

CO Willow Creek 

Reservoir

Weld 0903 3 2000 40 48 8.64 104 27 47.16 1.21

C

ONNEC

TICUT: 2 Lakes

CT Barkhamsted 

Reservoir

Litchfield 1117 3 2001 41 58 13.44 72 57 17.64 890.54

CT Rainbow Lake Fairfield 0938 3 2001 41 20 27.24 73 29 45.24 15.25

FLORID

A: 16 Lakes

FL Brown Lake Osceola 1425 4 2003 28 9 38.16 81 25 55.2 57.37

FL Chipco Lake Putnam 1060 3 2002 29 37 42.24 81 53 31.92 18.28

FL Crescent Lake Putnam/Flagler 0260 R 2003 29 27 11.628 81 29 34.296 6459FL Eagle Lake Polk 1575 4 2002 27 59 16.08 81 46 3.72 259.22

FL Lake Apopka Orange 0500 2 2001 28 37 8.76 81 37 19.56 12439.41
A-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

FL Lake Butler Union 0060 1 2000 30 2 12.12 82 20 21.84 362.69

FL Lake Manatee Manatee 1050 3 2002 27 28 46.2 82 18 27 593.3FL Lake Okeechobee Palm Beach/Hendry 0150 1 2001 27 10 30.72 80 47 45.6 4830.28

FL Lake Reedy Polk 0975 3 2002 27 44 16.8 81 29 58.2 1399.66FL Lake Tohopekaliga Osceola 1000 3 2002 28 13 57 81 22 20.28 7642.87

FL Lake Tsala Apopka Citrus 0100 1 2000 28 55 27.228 82 21 2.52 7733.98

FL Long Pond Hillsborough 0600 2 2001 27 57 57.96 82 15 57.24 22.39

FL Mill Dam Lake Marion 0135 1 2000 29 10 49.44 81 50 37.32 140.03

FL Unnamed lake Walton 0498 2 2001 30 28 57.36 86 19 40.44 1.53FL Unnamed lake Broward 0625 2 2001 26 1 34.32 80 15 39.6 5.43

FL Unnamed lake Palm Beach 0325 R 2003 26 35 5.64 80 11 10.68 2.32

GEORGIA: 15 Lakes

GA Allatoona Lake Bartow/Cherokee 1035 3 2000 34 8 12.48 84 37 54.84 4661.32

GA Boatright Lake Washington 0661 2 2000 32 48 40.32 82 42 29.52 12.58GA Demott Lake Colquitt 1411 4 2003 31 11 7.08 83 49 23.16

4

GA J. Strom Thurmond 

Reservoir

Columbia 1461 4 2000 33 39 32.04 82 23 53.88 10306.7

GA Johnson’s Lake Warren 0286 R 2003 33 21 54.72 82 38 8.52 25.72GA Lake Ashley 

(“Fishing Lake”)

Carroll 1360 4 2003 33 39 14.76 84 55 21.72 6.2

GA Lake Blue Ridge Fannin 0261 R 2003 34 50 29.04 84 15 57.6 1339.82

GA Lake Seminole Seminole 1547 4 2003 30 47 6.72 84 54 48.96 5137.63

GA Lake Sinclair Putnam 1561 4 2001 33 13 50.52 83 17 8.88 2070.71

GA Qualatchee Lake White 0061 1 2002 34 38 56.04 83 48 3.6 15.64

GA Reservoir 29 Madison 0636 2 2001 34 3 52.56 83 13 38.64 32.62

GA Unnamed lake Elbert 0186 1 2000 34 5 3.12 82 46 48.72 1.94

GA Unnamed lake Stewart 0036 1 2003 31 57 21.6 84 40 42.24 1.39
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-5

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

GA Unnamed lake Thomas 1097 3 2003 30 52 22.08 83 49 57.36 4.77GA West Point Lake Troup 0086 1 2002 33 3 44.28 85 8 0.6 9215.38

IDAHO: 7 Lakes

ID Bear Lake Bear Lake 0627 2 2000 42 0 13.32 111 19 58.476 28329

ID Blackfoot Reservoir Caribou 1452 4 2002 42 54 15.012 111 35 9.672 6475.2ID Brownlee Reservoir Washington 0079 1 2000 44 40 32.736 117 4 42.348 6070.5

ID Enos Lake #1 Valley 1028 3 2002 45 5 58.452 115 50 48.876 3.01

ID Loon Creek Lake #2 Valley 0904 3 2002 45 5 37.5 115 55 14.808 2.62

ID Palisades Reservoir Bonneville 0127 1 2000 43 14 36.96 111 6 40.68 6061.57

ID Priest Lake Bonner 0554 2 2000 48 34 4.368 116 51 27.504 9453.8

ILLIN

OIS: 10 Lakes

IL Buck Lake De Kalb 0041 1 2000 41 38 51 88 39 36 3.56

IL Kincaid Lake Jackson 1565 4 2002 37 49 7.32 89 28 42.24 972.39

IL Lake Inverness Cook 0241 R 2003 42 5 39.48 88 5 3.12 6.57

IL Otter Lake Macoupin 0115 1 2001 39 27 4.32 89 53 35.16 126.16

IL Rend Lake Franklin 1065 3 2001 38 4 52.32 88 58 26.76 832.64IL Shook’s Pond Rock Island 0140 1 2000 41 27 17.64 90 36 11.16 1.67IL Unnamed lake Williamson 0015 1 2000 37 46 23.88 88 47 0.6 6.2

IL Unnamed lake Tazewell 0515 2 2000 40 35 1.68 89 35 7.8 17.48

IL Unnamed lake Saline 1465 4 2002 37 44 13.2 88 30 28.08 7.87IL Wolf Lake Cook 0491 2 2001 41 39 52.2 87 31 57.72 323

INDI

A

N

A: 7 Lakes

IN Baire Lake Putnam 0141 1 2000 39 43 58.8 86 45 17.64 3.03IN Fox Lake Steuben 1516 4 2003 41 37 36.48 85 1 24.96 53.2IN Geist Reservoir Hamilton 0616 2 2001 39 55 41.52 85 56 33 683.06

IN Hardy Lake Scott 0941 3 2002 38 46 21.36 85 41 20.04 315.77
A-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

IN Turtle Creek 

Reservoir

Sullivan 0590 2 2001 39 4 1.92 87 31 42.96 605.95

IN Unnamed lake Montgomery 1541 4 2003 40 2 5.64 86 57 10.8 5.24IN Winona Lake Kosciusko 0466 2 2001 41 13 22.44 85 50 0.96 216.43

IO

WA: 5 Lakes

IA Diamondhead Lake Guthrie 1090 3 2002 41 32 59.28 94 15 33.84 40.03

IA Morse Lake Wright 0165 1 2000 42 50 20.04 93 41 41.28 41.11

IA Percival Lake Fremont 0615 2 2001 40 46 37.56 95 48 36.72 6.39

IA Saylorville Lake Polk 1040 3 2002 41 45 11.52 93 43 53.76 2041.2

IA Unnamed lake Wapello 0965 3 2002 40 58 26.4 92 22 25.68 12.99

KANS

AS: 4 Lakes

KS Tuttle Creek Lake Pottawatomie 0119 1 2000 39 27 25.2 96 42 4.68 2152.55

KS Unnamed lake Jackson 1119 3 2002 39 30 8.64 95 36 3.6 5.43KS Unnamed lake Greenwood 0293 R 2003 37 56 5.28 96 10 45.84 1.53KS Unnamed lake Woodson 1568 4 2003 37 53 13.56 95 36 43.2 1.81

KE

NTU

CKY: 7 Lakes

KY Barkley Lake Lyon 1361 4 2003 37 1 24.24 88 7 18.48 7.75

KY Green River Lake Adair 1012 3 2002 37 14 0.6 85 16 15.6 3190.89

KY Herrington Lake Boyle 0641 2 2001 37 41 6 84 42 52.56 1084.43KY Lake Cumberland Pulaski 1062 3 2003 36 58 26.4 84 46 44.76 231.04

KY Unnamed lake Livingston 0465 2 2001 37 16 55.92 88 29 39.12 13.42

KY Unnamed lake Nelson 0640 2 2001 37 47 52.08 85 38 50.28 2.56

KY Unnamed lake Fleming 0266 R 2003 38 23 12.84 83 31 20.64 7.11

LOUISI

A

N

A: 7 Lakes

LA Catahoula Lake LaSalle 0274 R 2002 31 30 20.34 92 7 30.72 10846

LA Lac des Allemands St. John the Baptist 0999 3 2000 29 55 14.95 90 34 18.05 5957.2

LA Lake Bistineau Webster 0173 1 1999 32 26 17.16 93 23 12.48 6282.91
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-7

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

LA Lake Bussey Brake Morehouse 1548 4 2002 32 51 52.20 91 55 44.04 848.31

LA Miller’s Lake Evangeline 1374 4 2002 30 45 6.84 92 21 18.00 1245.69

LA Salt Lake Calcasieu 1074 3 2001 30 15 23.40 93 24 56.88 63.59

LA Unnamed lake Pointe Coupee 1474 4 2003 30 42 43.20 91 43 56.64 16.31

MAINE: 25 Lakes

ME Chandler Pond Piscataquis 1460 4 2003 46 18 23.04 69 3 46.08 51.83ME Cuxabexis Lake Piscataquis 0660 2 2001 46 6 22.68 69 17 54.24 247.09ME Green Lake Hancock 0566 2 2001 44 38 53.88 68 29 53.52 1267.24ME Hadley Lake Washington 0917 3 2002 44 47 10.68 67 26 56.04 680.2ME Hale Pond Piscataquis 0285 R 2003 45 48 36 68 58 35.76 64.84ME Heald Ponds Somerset 0042 1 2000 45 11 4.2 69 51 48.6 8.72

ME Little Pond Oxford 0192 1 2000 44 9 11.88 70 35 16.44 10.67

ME Little River Lake Washington 0516 2 2001 45 9 33.84 67 49 14.52 29.41

ME McCurdy Pond Lincoln 0642 2 2001 44 0 35.28 69 27 11.88 79.6

ME Megunticook Pond Waldo 1366 4 2003 44 15 46.08 69 6 47.52 573.61ME Middle Range Pond Androscoggin 0617 2 2001 44 1 16.32 70 23 57.12 14.61

ME Moose Pond Cumberland 0217 1 2000 44 3 14.04 70 48 17.64 679.43

ME Moosehead Lake Piscataquis 0492 2 2001 45 40 43.104 69 43 19.092 30308

ME Mooselookmeguntic 

Lake 

Oxford 0667 2 2001 44 53 12.48 70 49 43.68 6597

ME Parker Pond Kennebec 1067 3 2002 44 29 8.88 70 1 49.44 611.44ME Peaked Mountain 

Pond

Piscataquis 0935 3 2002 46 30 27.36 69 5 14.64 5.01

ME Pemadumcook Lake Piscataquis 1041 3 2002 45 41 15 68 54 5.4 7453.06

ME Puffer’s Pond Penobscot 0242 R 2003 45 0 56.88 69 15 37.08 46.36

ME Ragged Lake Piscataquis 0210 1 2000 45 49 13.08 69 22 4.08 1046.61

ME Seboomook Lake Somerset 1560 4 2003 45 54 54 69 52 13.44 2571.1
A-8

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

ME Spednik Lake Washington 0966 3 2002 45 37 17.76 67 38 32.28 5570.94ME Stiles Lake Hancock 0166 1 2000 44 58 23.16 68 0 34.2 16.99

ME Upper Middle 

Branch Pond

Hancock 0092 1 2000 44 52 34.32 68 13 37.2 103.76

ME Wallagrass Lakes Aroostook 0635 2 2001 47 6 20.16 68 42 51.48 100.43

ME Wood Pond Somerset 1442 4 2003 45 37 9.12 70 16 58.44 819.41

MARYLAND: 1 Lake

MD Deep Creek Lake Garrett 1439 4 2002 39 30 15.48 79 19 17.4 1449.35

MASS

A

CHUSETTS: 7 Lakes

MA Bent’s Pond Worcester 0493 2 2001 42 31 37.92 71 59 55.68 8.72

MA Carbuncle Pond Worcester 0592 2 2001 42 8 7.08 71 52 7.32 3.94

MA North Watuppa 

Pond

Bristol 0017 1 2000 41 42 11.16 71 6 27 673.72

MA Quabbin Reservoir Worcester 0567 2 2001 42 24 5.4 72 18 31.32 9535.65

MA Rockwell Pond Worcester 1443 4 2003 42 31 37.92 71 46 9.12 3.68

MA Seymour Pond Barnstable 0467 2 2001 41 43 26.04 70 5 34.08 68.75

MA Westboro Reservoir Worcester 0992 3 2002 42 14 36.6 71 36 16.92 1.33

MIC

HIGAN: 21 Lakes

MI Burt Lake Cheboygan 0459 2 2001 45 27 35.784 84 39 55.584 6928.25MI Chenango Lake Livingston 1564 4 2003 42 30 13.68 83 53 41.28 12.35

MI Cloverleaf Lake Alger 0934 3 2002 46 33 32.4 86 5 13.92 4.79

MI Fire Lake Baraga 0309 R 2003 46 29 57.12 88 11 29.76 10.83

MI Glen Lake Leelanau 1459 4 2003 44 52 14.88 86 1 5.16 559.97

MI Gogebic Lake Gogebic 1534 4 2003 46 30 29.556 89 35 10.5 5170MI Haney Lake Van Buren 0591 2 2003 42 15 8.64 86 7 29.28 11.9

MI Horseshoe Lake Ogemaw 0589 2 2001 44 24 57.96 84 16 49.8 14.45

MI Houghton Lake Roscommon 0639 2 2001 44 20 59.64 84 42 59.4 8067.91
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-9

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

MI Lake Chapin Berrien 0016 1 2000 41 55 37.56 86 20 52.8 220.36

MI Lake Paradise Emmet 0659 2 2001 45 41 6.72 84 45 2.52 767.18

MI Lake Roland Houghton 0534 2 2001 46 53 18.24 88 51 5.4 107.27MI Long Lake Kalamazoo 1116 3 2002 42 11 41.28 85 31 14.16 198.23

MI Miner’s Lake Alger 0284 R 2003 46 28 50.52 86 32 16.8 6.01

MI Norvell Lake Jackson 0664 2 2001 42 8 48.12 84 12 29.52 12.38

MI Seven Mile Pond Alpena 0984 3 2002 45 5 48.48 83 30 34.92 555.78

MI Torch Lake Antrim 0634 2 2001 44 58 41.52 85 18 54.72 7503.08

MI Walloon Lake Emmet 0009 1 2000 45 18 1.8 85 0 41.4 1832.12

MI West Lake Lapeer 0014 1 2000 43 5 56.76 83 24 53.64 1.12MI White Lake Oakland 0464 2 2001 42 40 8.76 83 33 51.48 198.12

MI Wintergreen Lake Kalamazoo 0116 1 2000 42 23 51.36 85 23 5.64 13.49

MINNESOTA: 58 Lakes

MN Agate Lake Crow Wing 0630 2 2001 46 29 45.96 93 54 46.8 65.74

MN Bass Lake Wright 0507 2 2001 45 19 18.12 94 6 7.92 86.47

MN Belle Lake Meeker 1357 4 2003 44 58 53.04 94 25 33.24 361.91MN Blind Lake Aitkin 1455 4 2000 46 39 0.72 93 44 45.96 119.92

MN Cantlin Lake Sherburne 0033 1 2000 45 29 9.24 93 35 13.2 41.26

MN Cass Lake Beltrami 0205 1 1999 47 25 23.484 94 31 53.94 12050

MN Charlotte Wright 1508 4 2000 45 9 3.24 93 44 48.12 94.11MN Cork Lake Douglas 0257 R 2003 45 52 25.68 95 29 2.76 41.04MN Dead Lake Otter Tail 1431 4 2000 46 28 45.48 95 44 58.2 2987.93MN Diamond Lake Kandiyohi 1382 4 2003 45 10 59.52 94 50 33.72 626.23

MN Dick Lake Cook 0085 1 2001 47 51 54.72 90 29 39.48 52.8MN East Leaf Lake Otter Tail 0906 3 1999 46 23 54.96 95 25 19.92 170.1

MN First Lake Pine 0633 2 2001 46 18 52.56 92 49 11.64 31.02
A-10

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

MN Fish Lake Reservoir St. Louis 0605 2 1999 46 56 20.76 92 16 25.32 1214.34

MN Flat Lake Becker 1506 4 2003 46 58 44.4 95 39 17.28 741.28

MN Florida Lake Kandiyohi 0957 3 2001 45 14 10.32 95 3 49.68 210.53

MN Fox Lake Becker 0081 1 1999 46 46 49.8 95 54 30.24 55.54

MN Fox Lake Beltrami 0655 2 2001 47 36 33.48 94 50 30.48 63.87MN Hendricks Lake Lincoln 0457 2 2000 44 29 43.8 96 27 44.64 616

MN Hubert Lake Crow Wing 0155 1 2000 46 29 13.92 94 16 7.32 510.95

MN Isabella Lake Lake 0985 3 2003 47 48 39.6 91 17 29.04 666.76

MN Kabekona Lake Hubbard 1480 4 2003 47 10 0.48 94 45 26.28 974.89MN Kekekabic Lake Lake 0035 1 2002 48 4 7.68 91 10 26.4 690.72

MN La Salle Lake Hubbard 0005 1 2000 47 20 29.4 95 9 52.92 90.11MN Lac La Croix St. Louis 0485 2 1999 48 17 33.72 92 4 40.08 5768.93

MN Lake Carlos Douglas 1532 4 2000 45 57 50.76 95 21 22.32 1039.76MN Lake Geneva Freeborn 0207 1 2000 43 47 31.2 93 16 26.76 693.82

MN Lake Minnetonka Hennepin 1032 3 2002 44 54 34.2 93 38 10.68 1699.75

MN Lake of the Woods Lake of the Woods 1430 4 2003 48 58 12.072 95 12 13.248 384622

MN Lake Pepin Goodhue 1457 4 2003 44 30 55.8 92 18 25.56 5075MN Lake Washington Le Sueur 1057 3 2002 44 15 15.12 93 52 38.64 582.48

MN Lake Washington Meeker 0307 R 2003 45 4 15.6 94 22 20.64 979.68

MN Lake Winona Winona 0932 3 2003 44 2 29.4 91 39 22.32 32.22

MN Leech Lake Cass 1055 3 2002 47 9 20.484 94 23 29.688 44280

MN Linwood Lake St. Louis 0130 1 2000 47 19 10.92 92 6 20.52 2.5

MN Long Lake Hubbard 0031 1 2000 46 53 10.68 94 59 57.84 783.5

MN Many Point Lake Becker 0481 2 2001 47 4 39 95 32 17.16 676.86

MN Mille Lacs Mille Lacs 0933 3 2003 46 14 17.16 93 38 35.16 51699.73

MN Moberg Lake St. Louis 0530 2 2001 46 48 48.96 92 54 40.32 13.94
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-11

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

MN Mora Lake Cook 0010 1 2001 48 1 17.4 90 56 33.36 94.49

MN Mud Lake Traverse 0905 3 2002 48 19 45.552 95 58 18.48 9591

MN Namakan Lake St. Louis 0110 1 1999 48 33 28.512 92 49 25.932 5686MN North Turtle Lake Otter Tail 1380 4 2001 46 18 22.68 95 47 57.48 600.51

MN O’Dowd Lake Scott 0182 1 2000 44 44 28.32 93 31 0.48 118.14MN Pokegama Lake Itasca 0055 1 2000 47 10 51.6 93 34 37.2 6313

MN Portage Lake Cass 0280 R 2003 47 20 35.16 94 18 42.12 605.98

MN Red Lake Beltrami 0980 3 2002 47 57 43.02 95 1 30.288 61512.47

MN Rice Lake Stearns 0157 1 2000 45 22 29.64 94 36 56.52 617.62MN Rice Lake Itasca 0255 R 2003 47 12 48.24 93 40 56.64 276.63

MN Shamineau Lake Morrison 0908 3 2002 46 15 13.32 94 36 1.8 547.87

MN Snowbank Lake Lake 0235 R 2003 47 59 3.48 91 25 9.12 1889.88MN South McDougal 

Lake

Lake 0460 2 2000 47 36 51.48 91 33 29.16 112.64

MN Spider Lake Itasca 1530 4 2003 47 29 27.6 93 34 36.84 546.03

MN Sturgeon Lake Pine 0183 1 2000 46 22 48.72 92 45 22.32 666.38

MN Vermilion Lake St. Louis 1110 3 2002 47 52 5.196 92 18 26.172 19875

MN White Iron Lake St. Louis/Lake 1010 3 2001 47 53 53.88 91 45 13.32 2404.36

MN White Sand Lake Crow Wing 0083 1 2000 46 21 6.48 94 17 12.48 158.52MN Woman Lake Cass 0180 1 2000 46 57 30.96 94 16 21.72 2395.76

MISSISSIPPI: 9 Lakes

MS Bailey Lake Carroll 0146 1 2000 33 28 37.2 89 50 15 50.29

MS Ben Lilly Pond Monroe 1122 3 2002 33 43 17.4 88 42 40.32 4.76

MS Enid Lake Yalobusha 0997 3 2002 34 8 50.676 89 51 43.452 11230MS Grenada Lake Grenada 1096 3 2002 33 49 54.804 89 44 2.364 26154

MS H Johnson Pond Yazoo 0322 R 2003 32 37 41.16 90 28 49.8 5.53MS Hollis Lee’s Lake Claiborne 0624 2 2001 32 1 49.44 90 46 57.36 37
A-12

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

MS Lake Lucille Lauderdale 0098 1 2000 32 34 30 88 32 38.76 12

MS Sardis Reservoir Panola 0672 2 2001 34 26 55.032 89 42 46.476 23684

MS Unnamed lake Carroll 1546 4 2003 33 35 58.2 90 1 49.44 8.1

MISSOURI: 11 Lakes

MO Lake Wapapello Wayne 0290 R 2003 36 58 3.72 90 21 15.12 2523.23

MO Mark Twain Lake Ralls 1440 4 2003 39 30 46.44 91 42 36 3551.37

MO Table Rock Lake Stone 0543 2 2003 36 33 32.4 93 23 45.96 12409.59MO Tressle Hole New Madrid 1437 4 2003 36 33 12.6 89 26 58.92 9.93

MO Truman Reservoir St Clair 1393 4 2003 38 10 12 93 34 18.84 9246.25

MO Unnamed lake Dade 0618 2 2002 37 22 33.6 93 41 24 3

MO Unnamed lake Jasper 1068 3 2002 37 17 22.92 94 31 58.08 14.27

MO Unnamed lake Cooper 0240 R 2003 38 54 46.44 92 47 36.96 4.83

MO Unnamed lake Polk 0318 R 2003 37 46 16.32 93 33 17.28 5.54

MO Unnamed lake Knox 1490 4 2003 40 1 54.12 92 4 6.96 4.27

MO Unnamed lake Callaway 1515 4 2003 38 57 54.36 91 58 57.72 9.35

MO

NTA

N

A: 16 Lakes

MT Bighorn Lake Big Horn 0053 1 2001 45 10 14.16 108 6 14.04 6942.75MT Bynum Reservoir Teton 1429 4 2003 47 56 45.6 112 26 0.6 1295.69

MT Clear Lake Mineral 1104 3 2001 47 16 9.12 115 24 24.84 3.09MT Cliff Lake Flathead 1079 3 2002 48 9 46.08 113 53 22.92 9.3

MT Ennis Lake Madison 1504 4 2003 45 25 51.24 111 40 55.56 1490.89

MT Fort Peck Reservoir Valley 0084 1 2000 47 44 0.6 106 44 36.6 98766.25

MT Frenchman Pond Phillips 1434 4 2003 48 42 19.8 107 13 33.24 231.25

MT Hebgen Lake Gallatin 0952 3 2002 44 47 13.02 111 14 58.74 4856.25

MT Krieder’s Pond Garfield 0104 1 2000 47 7 47.28 107 28 39.36 5.88MT Laird Pond Carter 0178 1 2000 45 37 24.24 104 40 28.92 7.75
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-13

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

MT Lake Elwell Liberty 0029 1 2000 48 22 39 111 12 15.84 1075.54

MT Lake Koocanusa Lincoln 0604 2 2002 48 35 11.04 115 14 5.28 11462.51

MT Leigh Lake Lincoln 1029 3 2002 48 13 15.6 115 39 55.08 52

MT Rape Creek 

Reservoir

Beaverhead 0153 1 2000 44 59 50.28 113 11 42 9.64

MT Upper Cold Lake Missoula 0454 2 2001 47 33 25.2 113 54 4.32 22.84

MT Upper Two 

Medicine Lake

Glacier 0254 R 2003 48 27 54.72 113 27 27 61.42

NEBRASKA: 5 Lakes

NE Enders Reservoir Chase 1444 4 2002 40 25 55.92 101 33 14.04 652.43

NE Harlan County 

Reservoir

Harlan 0244 R 2003 40 3 30.6 99 18 12.96 5185.54

NE Jeffrey Reservoir Lincoln 0494 2 2000 40 56 27.6 100 24 34.2 226.1

NE Lake McConaughy Keith 1403 4 2002 41 15 1.08 101 50 53.16 11464.25NE Lake Minatare Scotts Bluff 0453 2 2000 41 56 1.32 103 29 42 784.3

NEVA

D

A: 4 Lakes

NV Chimney Reservoir Humboldt 1451 4 2002 41 24 52.56 117 9 11.88 880.93NV Lake Mead Clark 0652 2 2000 36 16 57.36 114 22 23.16 39372.55NV Pyramid Lake Washoe 0902 3 2003 40 1 19.2 119 33 11.88 44232.8NV Ruby Lake Elko 0926 3 2001 40 10 20.64 115 28 10.2 38.43

NEW HAMPSHIRE: 5 Lakes

NH Big Diamond Pond Coos 0292 R 2003 44 57 11.16 71 18 44.28 67.92

NH Horn Pond Carroll 0317 R 2003 43 33 39.6 70 57 41.4 91.56NH Lake Winnipesaukee Carroll/Belknap 0167 1 2000 43 36 9.36 71 20 27.6 18545.11NH Little Island Pond Hillsborough 0243 R 2003 42 43 39.72 71 17 16.08 64.89NH Newfound Lake Grafton 0517 2 2001 43 39 34.2 71 46 2.64 1717.53
A-14

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

NEW JERSEY: 2 Lakes

NJ Unnamed lake Camden 0013 1 2000 39 47 5.28 74 51 45.72

4

NJ Verona Lake Essex 1063 3 2002 40 49 36.84 74 14 50.28 5.47

NEW MEXIC

O: 2 Lakes

NM Brantley Reservoir Eddy 1369 4 2001 32 36 46.19 104 21 3.46 8498

NM Navajo Reservoir Rio Arriba 0169 1 2000 36 31 4.08 107 36 37.80 1892.41

NEW YORK: 17 Lakes

NY Brant Lake Warren 0593 2 2000 43 42 55.44 73 42 25.2 571.85

NY Chautauqua Lake Chautauqua 0114 1 1999 42 7 59.196 79 22 40.116 5438NY Colgate Lake Greene 0488 2 2000 42 14 8.16 74 7 8.4 10.67NY Copake Lake Columbia 0138 1 2000 42 8 38.76 73 35 47.4 157.5

NY Goldfish Pond Suffolk 1463 4 2003 40 56 31.2 72 19 45.12 1.34

NY Grizzle Ocean Essex 1518 4 2002 43 49 13.8 73 35 42.72 7.6

NY Jamesville Reservoir Onondaga 0238 R 2003 42 58 23.52 76 4 9.12 87.71NY Lake DeForest Rockland 1488 4 2002 41 9 42.12 73 57 31.32 93.52

NY Little Wolf Pond Franklin 0542 2 2000 44 15 13.32 74 28 47.64 65.08

NY Moose Lake Herkimer 1513 4 2003 43 50 0.96 74 50 41.64 507.45NY Mud Pond Clinton 1542 4 2002 44 33 42.12 73 55 21.36 45.43

NY Northville Pond Fulton 1013 3 2001 43 13 44.76 74 10 13.44 7.6

NY Seneca Lake Yates 0088 1 2003 42 37 39.72 76 55 6.96 17413.27NY Southern South 

Lake

Putnam 0613 2 2001 41 30 9.36 73 42 14.76 4.26

NY Sylvia Lake St. Lawrence 0113 1 1999 44 15 9.72 75 24 50.04 124.86

NY Tupper Lake Franklin 0067 1 2001 44 11 29.04 74 30 0.72 2583.95

NY Whitney Pond Oswego 0913 3 2001 43 26 0.96 75 59 23.28 32.07
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-15

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

NORTH CAROLIN

A: 8 Lakes

NC B. Everett Jordan 

Lake

Chatham 0162 1 2000 35 46 23.52 79 0 59.4 5787

NC Kings Mountain 

Reservoir

Cleveland 0062 1 2000 35 18 3.6 81 27 21.24 551.51

NC Lake Gaston Warren 0164 1 2000 36 32 27.6 78 1 8.4 7951

NC Lake Norman Catawba 0262 R 2003 35 37 35.4 80 56 40.2 13211.68

NC Lake Phelps Washington 0139 1 2000 35 46 7.356 76 27 36.18 6718NC Mountain Island 

Reservoir

Gaston/Mecklenburg

0537 2 2001 35 21 2.88 80 58 11.28 1403.92

NC San-Lee Park Lake Lee 0312 R 2003 35 28 53.04 79 7 31.08 7.29NC Smith Lake Cumberland 0612 2 2002 35 8 9.6 78 55 38.64 34.07

NORTH DAKOTA: 8 Lakes

ND Devils Lake Ramsey 0030 1 2001 48 13 15.6 98 48 19.08 7119.61

ND Dry Lake Mcintosh 1456 4 2000 46 7 5.88 99 28 20.28 203.78

ND Dry Lake Ramsey 0105 1 2001 48 15 8.64 98 58 27.12 2196.46

ND Epping - 

Springbrook Dam 

Williams 0484 2 2001 48 15 43.92 103 25 0.48 59.85

ND Homme Lake Walsh 0230 R 2003 48 24 24.84 97 48 4.68 75.74ND Horsehead Lake Kidder 0956 3 2001 47 2 34.8 99 47 2.76 1355.91ND Long Lake Kidder 0006 1 2000 46 44 20.4 100 3 46.8 1299.72

ND Twin Lakes South La Moure 0281 R 2003 46 24 8.28 98 15 45.72 108.46

OHIO: 7 Lakes

OH Clouse Lake Perry 1491 4 2003 39 46 1.56 82 17 56.4 13.14

OH Darrell Rose’s Pond Marion 0541 2 2001 40 37 20.28 83 7 39.36 2.16

OH Lake Rupert Vinton 0066 1 2000 39 11 23.28 82 31 19.56 133.07

OH Tom Porter’s Pond Licking 0513 2 2001 39 57 9.36 82 14 1.68 1.52

OH Unnamed lake Lucas 1114 3 2002 41 36 25.92 83 40 48.72 5.3
A-16

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

OH Unnamed lake Trumbull 1514 4 2003 41 18 24.84 80 34 16.68 2.38OH Unnamed lake Hancock 0963 3 2002 41 3 4.32 83 34 28.56 1.18

OKLAHOMA: 21 Lakes

OK Broken Bow Lake Mccurtain 0499 2 2000 34 16 49.08 94 40 46.92 5342.04OK Camp Simpson Lake Johnston 1123 3 2001 34 25 7.32 96 32 49.20 41.33OK Coalgate City Lake Coal 0924 3 2001 34 34 40.80 96 14 16.80 159.1

OK Fort Cobb Lake Caddo 0069 1 1999 35 11 53.52 98 29 27.24 1654.07

OK Great Salt Plains 

Lake

Alfalfa 1544 4 2002 36 44 1.32 98 10 39.36 4041.26

OK Hugo Lake Choctaw 0099 1 2000 34 5 8.52 95 25 26.04 4950.45

OK Keystone Lake Creek/Pawnee 0219 1 1999 36 14 53.16 96 22 4.80 5454.54OK Lake Altus-Lugert Kiowa 1494 4 2002 34 55 32.52 99 18 42.12 1810.44OK Lake El Reno Canadian 0944 3 2001 35 31 19.56 97 59 31.56 62.72

OK Lake Hudson Mayes 1093 3 2001 36 26 2.04 95 11 30.12 8.22OK Lake Lawtonka Comanche 0269 R 2003 34 45 28.44 98 30 50.04 959.22

OK Lake Ponca Kay 0294 R 2003 36 44 19.68 97 2 4.56 184.84

OK Oologah Lake Rogers 0068 1 2000 36 34 55.56 95 35 31.92 6099.87

OK Sardis Lake Latimer 0249 R 2003 34 46 21 95 4 9.84 63.2

OK Tenkiller Ferry Lake Cherokee 1468 4 2002 35 42 41.76 94 57 21.24 5350.48

OK Unnamed lake Mcclain 0544 2 2000 34 59 12.48 97 31 44.76 12.21OK Unnamed lake Osage 0669 2 2000 36 36 48.60 96 47 36.60 2.18OK Unnamed lake Stephens 1423 4 2002 34 35 12.12 97 38 8.52 14.67

OK Unnamed lake Le Flore 1524 4 2002 35 16 8.76 94 48 20.52 1.18

OK Unnamed lake Rogers 1543 4 2002 36 32 46.32 95 38 43.80 99.47

OK Wewoka Lake Seminole 1469 4 2002 35 11 49.20 96 31 1.92 144.51
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-17

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

OREGON: 9 Lakes

OR Barney Reservoir Washington 1454 4 2003 45 26 42.612 123 23 19.968 81.14OR Crater Lake Klamath 0451 2 2001 42 56 57.84 122 5 41.1 5318.03OR Denley Reservoir Douglas 1001 3 2002 43 22 22.476 123 14 38.724 5.91

OR Elk Lake Marion 0901 3 2002 44 49 22.872 122 7 7.968 25.95

OR Lake Owyhee Malheur 1353 4 2003 43 29 57.084 117 21 3.672 4576.85

OR Lake Umatilla Klickitat 0629 2 2002 45 43 32.916 120 31 53.544 11697.92

OR Malheur Lake Harney 0326 R 2003 43 18 35.24 118 47 32.03 5961.67

OR Unnamed lake Linn 0076 1 2002 44 33 9.54 123 14 20.112 7.23

OR Wickiup Reservoir Deschutes 1501 4 2003 43 41 29.868 121 43 19.668 4110.44

PENNS

YLVANI

A: 9 Lakes

PA Crooked Creek Lake Armstrong 0489 2 2000 40 40 55.92 79 29 8.52 151.44PA Francis Slocum State 

Park Lake

Luzerne 0288 R 2003 41 20 12.48 75 53 40.56 66.62

PA Keystone Lake Westmoreland 0239 R 2003 40 22 24.96 79 22 58.08 23.52

PA Lake Sabula Clearfield 0039 1 2002 41 9 29.16 78 39 57.24 13.36

PA Pike Lake #3 Pike 0188 1 1999 41 15 1.44 74 57 5.04 5.61

PA Shenango River Lake Mercer 1014 3 2001 41 17 34.08 80 25 28.92 1490.57

PA Unnamed lake Franklin 0089 1 1999 39 56 42.36 77 48 43.56 1.6

PA Unnamed lake Bradford 0213 1 2000 41 56 39.48 76 23 19.68 9.65

PA Whitney Lake Wayne 1088 3 2001 41 28 9.12 75 15 0.72 46.01

RHO

DE ISL

AND: 2 Lakes

RI Arnold Mills 

Reservoir

Providence 1567 4 2003 41 59 2.04 71 24 23.4 6.44

RI Gorton Pond Kent 1517 4 2003 41 42 18.72 71 27 33.84 21.82
A-18

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

SOUTH CAROLIN

A: 3 Lakes

SC Hartwell Reservoir Oconee 1486 4 2001 34 34 42.24 83 6 6.12 6881.09

SC Lake Murray Newberry 0987 3 2000 34 5 15.72 81 28 0.12 19601.57

SC Lake Wateree Kershaw 1562 4 2001 34 25 9.48 80 48 32.04 5548.26

SOUTH DAKOTA: 9 Lakes

SD Angostura Reservoir Fall River 1553 4 2002 43 18 28.08 103 25 4.44 1741.5

SD Corsica Lake Douglas 1031 3 2001 43 24 53.64 98 17 31.2 37.99

SD Hayes Lake Stanley 0982 3 2000 44 21 57.6 101 0 44.64 24.6

SD Lake Mitchell Davison 0007 1 2000 43 45 23.04 98 3 21.6 283.62

SD Lake Oahe Dewey 1056 3 2002 44 52 26.76 100 31 59.16 61520.39

SD Mud Lake Kingsbury 1107 3 2001 44 28 44.76 97 35 33 119.08

SD Pelican Lake Codington 0107 1 2001 44 52 4.08 97 10 48.36 1124.44

SD Shadehill Reservoir Perkins 0056 1 2000 45 46 11.64 102 15 16.92 958.83

SD South Waubay Lake Day 1507 4 2002 45 22 49.08 97 27 5.04 940.18

TENNESSEE: 8 Lakes

TN Dale Hollow Lake Clay 0487 2 2001 36 33 54.36 85 16 29.28 10725.65TN Douglas Reservoir Jefferson 1487 4 2003 35 59 50.28 83 21 54.36 11138.56

TN J. Percy Priest Lake Davidson 0087 1 2000 36 5 56.76 86 33 37.08 5369.73

TN Kentucky Lake Henry/Stewart 1036 3 2002 36 25 53.76 88 4 45.12 46342.27

TN Norris Lake Union 0187 1 2000 36 18 40.68 83 49 58.8 3749.23

TN Pine Lake Henderson 0561 2 2001 35 33 29.16 88 24 54 184.41

TN Ridgetop Lake Robertson 0587 2 2001 36 24 46.08 86 45 51.84 5.41

TN Tellico Lake Monroe 1536 4 2003 35 36 30.96 84 13 4.8 6638.63

TE

X

AS: 41 Lakes

TX Arnold Lake Houston 0220 1 1999 31 10 9.84 95 41 0.24 23.46

TX ASCS Lake Riser 638 Collin 0598 2 2002 33 18 28.08 96 40 9.48 6.77
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-19

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

TX B.A. Steinhagen 

Lake

Tyler/Jasper 0524 2 2000 30 50 56.29 94 11 30.59 5549

TX Bardwell Reservoir Ellis 0246 R 2003 32 17 11.04 96 40 10.92 1125.31

TX Caddo Lake Marion 1373 4 2003 32 44 56.76 94 7 32.16 10794

TX E.V. Spence 

Reservoir

Coke 0021 1 2000 31 56 13.56 100 34 39.72 6055

TX Hubbard Creek 

Reservoir

Stephens 0596 2 2000 32 46 31.08 99 0 24.48 5960.07

TX Lake Arrowhead Clay 0048 1 2000 33 42 37.08 98 22 44.40 6561

TX Lake Belton Bell 0921 3 2001 31 9 59.40 97 34 25.68 1052.24

TX Lake Caballo Zavala 0196 1 2000 28 54 23.40 99 38 57.84 4.95TX Lake Childress Childress 0495 2 2000 34 27 40.68 100 20 57.12 120.72

TX Lake Coleman Coleman 0471 2 2000 32 2 13.20 99 30 50.40 705.13

TX Lake Conroe Montgomery 1570 4 2002 30 28 4.08 95 35 8.52 8029.64TX Lake Corpus Christi Live Oak 0221 1 1999 28 12 4.68 97 55 42.24 7831

TX Lake Falcon Zapata 1571 4 2003 26 55 17.76 99 19 7.68 15801.88

TX Lake Lavon Collin 0948 3 2001 33 7 49.44 96 32 39.84 80.66TX Lake Lewisville Denton 1473 4 2002 33 8 57.84 96 59 12.48 8589.78

TX Lake Logan Navarro 0496 2 2000 32 0 52.20 96 49 37.92 12.44

TX Lake Palestine Henderson 0673 2 2000 32 11 9.60 95 29 17.16 9533.34

TX Lake Pat Mayse Lamar 0573 2 2001 33 49 37.20 95 35 54.24 2389.57TX Lake Proctor Comanche 1045 3 2001 32 1 8.04 98 30 18.36 1913.14

TX Lake Sam Rayburn Nacogdoches 0324 R 2003 31 7 0.516 94 9 37.332 46336.7

TX Lake Tawakoni Hunt 0223 1 2000 32 56 57.12 96 0 38.52 15333.32

TX Lake Texoma Grayson 0473 2 2001 33 51 21.96 96 47 23.64 23548.87TX Lake Travis Travis 0070 1 2000 30 24 55.44 98 1 32.88 7239.69

TX Richland Reservoir Navarro/Freestone 1446 4 2003 31 58 47.14 96 13 1.92 18124
A-20

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

TX Rogers Lake Montgomery 0020 1 1999 30 11 6.36 95 23 14.64 9.31TX Stillhouse Hollow 

Reservoir

Bell 0645 2 2000 31 0 22.32 97 36 31.32 2663.76

TX Toledo Bend 

Reservoir

Panola 0974 3 2002 32 1 39.72 94 9 57.24 4.96

TX Toledo Bend 

Reservoir

Sabine 1399 4 2002 31 31 22.80 93 46 16.32 67141.13

TX Unnamed lake Young 1021 3 2001 33 23 43.80 98 40 37.56 8.72TX Unnamed lake Smith 1098 3 2001 32 34 5.52 95 30 57.96 6.07

TX Unnamed lake Henderson 0998 3 2002 32 4 54.48 96 2 20.40 10.27TX Unnamed lake Nacogdoches 1049 3 2002 31 33 15.12 94 33 7.92 3.24

TX Unnamed lake Hopkins 1073 3 2002 33 6 4.32 95 31 55.20 5.18TX Unnamed lake Karnes 1395 4 2002 28 56 11.40 98 0 58.32 8.01

TX Unnamed lake Mcculloch 1421 4 2002 31 18 57.24 99 14 0.60 5.97

TX Unnamed lake Collin 1498 4 2002 33 11 22.56 96 21 46.08 8.58

TX Unnamed lake Ellis 1370 4 2003 32 14 28.32 96 49 17.40 9.12

TX Unnamed lake Montague 1523 4 2003 33 29 19.32 97 36 39.60 5.38

TX Wright Patman Lake Bowie 0973 3 2003 33 17 3.84 94 19 55.56 11360.46

UTAH: 5 Lakes

UT Gunlock Reservoir Washington 0102 1 2000 37 15 42.48 113 46 31.8 100.83UT Olsen Slough Sanpete 0526 2 2003 39 4 14.52 111 50 15.72 14.5UT Strawberry Reservoir Wasatch 1051 3 2002 40 11 13.56 111 8 41.64 3171.67UT Unnamed lake Cache 0927 3 2003 41 49 53.4 111 53 17.88 6.96UT Utah Lake Utah 1476 4 2002 40 12 8.856 111 48 26.208 39231

VERMO

N

T: 2 Lakes

VT Lake Whitingham Windham 0093 1 2000 42 49 41.52 72 53 29.4 1564.85VT Lake Willoughby Orleans 0942 3 2002 44 44 52.8 72 3 33.12 670.01
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-21

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

VIRGINI

A: 10 Lakes

VA Banister Lake Halifax 1089 3 2001 36 47 14.28 78 57 14.76 154.42

VA Big Lake Halifax 0512 2 2000 36 40 55.2 79 5 25.08 10.42

VA Griggs Pond Henrico 0614 2 2000 37 25 23.88 77 18 37.44 5.81VA John H. Kerr 

Reservoir

Mecklenburg 0314 R 2003 36 33 54.72 78 28 36.48 16907.08

VA Lake Anna Louisa 0064 1 1999 38 3 51.84 77 50 37.68 5254.27

VA Lake Caroline Caroline 0264 R 2003 37 59 23.28 77 31 35.4 111.22

VA Lake Chesdin Chesterfield 1539 4 2002 37 15 43.2 77 36 8.64 1315.57

VA Lone Star Lake Suffolk 0964 3 2001 36 52 1.56 76 34 13.44 13.14

VA Unnamed lake Caroline 0090 1 2001 37 58 1.92 77 18 43.92 10.88

VA Unnamed lake Prince William 0914 3 2001 38 49 14.52 77 42 14.04 2.99

WASHINGTON: 14 Lakes

WA Buffalo Lake Okanogan 1379 4 2002 48 3 47.016 118 53 14.496 226.24

WA Calligan Lake King 1554 4 2002 47 36 18.54 121 39 57.168 116.96

WA Crescent Lake Clallam 0202 1 1999 48 5 5.316 123 46 2.712 1995.24

WA Dorothy Lake King 0654 2 2000 47 35 3.408 121 22 59.88 101.93WA Frenchman Hills 

Lake

Grant 0179 1 1999 46 58 54.876 119 35 17.772 138.34

WA Keechelus Lake Kittitas 0004 1 2001 47 20 2.94 121 21 34.056 955.35

WA Lake Chelan Chelan 0504 2 2000 48 1 33.96 120 19 55.38 13091

WA Lake Nahwatzel Mason 0279 R 2003 47 14 35.34 123 19 56.532 111.16WA Lake Wallula Benton 1479 4 2003 46 0 17.208 118 58 54.156 12960.93

WA Lone Lake Island 0979 3 2001 48 1 17.472 122 27 34.812 34.21

WA Patterson Lake Okanogan 0304 R 2003 48 27 31.896 120 14 40.308 51.6

WA Pend Oreille River Pend Oreille 1354 4 2002 48 25 48 117 17 33.072 935.8

WA Potholes Reservoir Grant 1054 3 2001 46 59 12.48 119 19 19.992 11333
A-22

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*† Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

WA Rimrock Lake Yakima 0529 2 2000 46 38 25.08 121 9 42.444 951.97

WEST VIRGINI

A: 1 Lake

WV Summersville Lake Nicholas 0637 2 2003 38 14 27.24 80 51 15.12 843.74

WISC

ONSIN: 18 Lakes

WI Big Gibson Lake Vilas 1084 3 2002 46 8 15.36 89 33 9.72 48.45WI Castle Rock Lake Adams/Juneau 0458 2 2001 43 56 6.72 89 59 9.6 5010.01WI Hatch Lake Waupaca 0983 3 2003 44 31 50.52 89 6 52.56 46.13

WI Irogami (Fish) Lake Waushara 0008 1 2001 44 3 57.24 89 13 56.28 116.45

WI Keyes Lake Florence 0259 R 2003 45 53 58.2 88 18 23.76 76.26

WI Lake DuBay/Big Eau 

Pleine Reservoir

Marathon 0208 1 2002 44 42 0 89 40 48 5356.14

WI Lake Winnebago Winnebago 0666 2 2003 44 0 7.2 88 24 56.52 53756.72

WI Lake Winter Sawyer 0133 1 2001 45 48 42.12 90 59 3.48 110.43

WI Pacwawong Lake Sawyer 0958 3 2002 46 9 1.8 91 20 21.84 76.05

WI Pewaukee Lake Waukesha 1566 4 2003 43 4 22.44 88 18 25.92 984.62

WI Rainbow Flowage Oneida 0308 R 2003 45 51 32.4 89 30 51.84 1291.37WI Spirit River Flowage Lincoln 0283 R 2003 45 26 38.76 89 49 24.24 640.24

WI Sweeney Lake Oneida 0134 1 2003 45 51 42.84 89 35 21.84 77.73

WI Turtle Flambeau 

Flowage

Iron 0608 2 2001 46 5 8.52 90 10 8.724 7648.59

WI Warner Lake Burnett 0058 1 2002 45 47 49.2 92 13 19.56 71.36

WI Whitefish Lake Sawyer 0258 R 2003 45 51 47.52 91 26 36.24 322.36WI Wolf Lake Fond Du Lac 0291 R 2003 43 51 51.48 88 12 28.44 33.84

WI Yellow River Barron 

Flowage #3

Barron 1058 3 2002 45 24 48.6 91 51 57.24 20.56
The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations

A-23

State Lake Name

Cou

nty

Lake

ID

Statis

tic

al

Year*†

Samplin

g

Year*

Latitu

de Lo

n

gitu

de Lake

Area

(ha) Deg

Min

Sec

Deg

Min

Sec

WYOMIN

G: 6 Lakes

WY Baptiste Lake Fremont 0527 2 2001 42 52 21.36 109 18 18 73.34

WY Buffalo Bill Reservoir Park 0528 2 2000 44 29 33 109 15 30.96 1384.63

WY Lake 79 Fremont 0052 1 2001 43 0 30.24 109 19 58.8 4.04

WY Lake DeSmet Johnson 1478 4 2001 44 29 3.48 106 45 12.24 821.12

WY Lewis Lake Teton 0602 2 2003 44 17 59.28 110 37 39.72 1115.92

WY Yellowstone Lake Teton 1078 3 2003 44 27 17.532 110 21 58.428 35223.98

* “Statistical Year” indicates the annual statistical subset that provides a nationally-representative sample (Sec. 2.2.2.). “Sampling Year” indicates the calendar year during 

which the samples were collected. 

† “R” indicates a reserve lake. Reserve lakes were added in the final year of sampling, since the initial list of 900 lakes contained a larger than expected number of lakes that 

did not meet the criteria for inclusion in the study. 
A-24

The National Study of Chemical Residues in Lake Fish Tissue

Appendix A: National Lake Fish Tissue Study Sampling Locations
The National Study of Chemical Residues in Lake Fish Tissue

Appendix B

Target Chemicals

The National Study of Chemical Residues in Lake Fish Tissue

Appendix B: Target Chemicals

B-1

Chemical

Group/

 Method Chemicals

CAS

Number

Method

Detection Limit

(MDL)1

Minimum

Level (ML) 

(Quantitation

Limit)1

Mercury

Method 1631B 

(1 chemical)

Mercury 7439-97-6 0.521 ng/g (ppb) 2 ng/g (ppb)

Arsenic 

Method 1632A

(5 chemicals)

Arsenate

Arsenite

Total Inorganic Arsenic

Dimethylarsonic Acid (DMA)

Monomethylarsonic Acid (MMA)

17428-41-0

22569-72-8

75-60-5

124-58-3

0.03 μg/g (ppm)

0.02 μg/g (ppm)

0.03 μg/g (ppm)

0.04 μg/g (ppm)

0.01 μg/g (ppm)

0.1 μg/g (ppm)

0.1 μg/g (ppm)

0.1 μg/g (ppm)

0.1 μg/g (ppm)

0.05 μg/g (ppm)

PCBs 

Method 1668A

(126 individual 

congeners plus 

33 congener 

groups of 2 to 

6 congeners)

PCB-1

PCB-2

PCB-3

PCB-4

PCB-5

PCB-6

PCB-7

PCB-8

PCB-9

PCB-10

PCB-11

PCB-12+13

PCB-14

PCB-15

PCB-16

PCB-17

PCB-18+30

PCB-19

PCB-20+28

PCB-21+33

PCB-22

PCB-23

PCB-24

PCB-25

PCB-26+29

PCB-27

PCB-31

PCB-32

PCB-34

PCB-35

PCB-36

PCB-37

PCB-38

PCB-39

PCB-40+41+71

PCB-42

PCB-43

PCB-44+47+65

0.8 ng/kg (ppt)

0.8 ng/kg (ppt)

0.6 ng/kg (ppt)

0.5 ng/kg (ppt)

0.7 ng/kg (ppt)

0.3 ng/kg (ppt)

0.4 ng/kg (ppt)

1.3 ng/kg (ppt)

0.5 ng/kg (ppt)

0.7 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

0.5 ng/kg (ppt)

0.4 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.8 ng/kg (ppt)

0.1 ng/kg (ppt)

4.2 ng/kg (ppt)

1.0 ng/kg (ppt)

0.2 ng/kg (ppt)

0.6 ng/kg (ppt)

0.8 ng/kg (ppt)

0.6 ng/kg (ppt)

3.5 ng/kg (ppt)

0.7 ng/kg (ppt)

0.5 ng/kg (ppt)

0.6 ng/kg (ppt)

0.5 ng/kg (ppt)

0.4 ng/kg (ppt)

0.5 ng/kg (ppt)

0.2 ng/kg (ppt)

0.4 ng/kg (ppt)

0.5 ng/kg (ppt)

1.6 ng/kg (ppt)

0.7 ng/kg (ppt)

1.4 ng/kg (ppt)

4.3 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

5.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

5.0 ng/kg (ppt)

0.5 ng/kg (ppt)

10.0 ng/kg (ppt)

2.0 ng/kg (ppt)

0.5 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

10.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

0.5 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

5.0 ng/kg (ppt)

2.0 ng/kg (ppt)

5.0 ng/kg (ppt)

10.0 ng/kg (ppt)
B-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix B: Target Chemicals

Chemical

Group/

 Method Chemicals

CAS

Number

Method

Detection Limit

(MDL)1

Minimum

Level (ML) 

(Quantitation

Limit)1

PCBs 

Method 1668A

(126 individual 

congeners plus 

33 congener 

groups of 2 to 

6 congeners)

(continued)

PCB-45+51

PCB-46

PCB-48

PCB-49+69

PCB-50+53

PCB-52

PCB-54

PCB-55

PCB-56

PCB-57

PCB-58

PCB-59+62+75

PCB-60

PCB-61+70+74+76

PCB-63

PCB-64

PCB-66

PCB-67

PCB-68

PCB-72

PCB-73

PCB-77

PCB-78

PCB-79

PCB-80

PCB-81

PCB-82

PCB-83+99

PCB-84

PCB-85+116+117

PCB-86+87+97+108+119+125

PCB-88+91

PCB-89

PCB-90+101+113

PCB-92

PCB-93+95+98+100+102

PCB-94

PCB-96

PCB-103

PCB-104

PCB-105

PCB-106

PCB-107+124

PCB-109

PCB-110+115

PCB-111

2.2 ng/kg (ppt)

1.2 ng/kg (ppt)

0.8 ng/kg (ppt)

1.4 ng/kg (ppt)

3.2 ng/kg (ppt)

4.3 ng/kg (ppt)

0.3 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.6 ng/kg (ppt)

0.5 ng/kg (ppt)

2.0 ng/kg (ppt)

0.4 ng/kg (ppt)

2.3 ng/kg (ppt)

0.7 ng/kg (ppt)

0.6 ng/kg (ppt)

5.2 ng/kg (ppt)

0.6 ng/kg (ppt)

0.4 ng/kg (ppt)

0.5 ng/kg (ppt)

0.7 ng/kg (ppt)

4.9 ng/kg (ppt)

0.7 ng/kg (ppt)

0.8 ng/kg (ppt)

0.8 ng/kg (ppt)

0.5 ng/kg (ppt)

0.6 ng/kg (ppt)

1.0 ng/kg (ppt)

0.9 ng/kg (ppt)

1.0 ng/kg (ppt)

4.5 ng/kg (ppt)

0.8 ng/kg (ppt)

0.6 ng/kg (ppt)

3.7 ng/kg (ppt)

0.1 ng/kg (ppt)

2.1 ng/kg (ppt)

0.6 ng/kg (ppt)

1.0 ng/kg (ppt)

0.4 ng/kg (ppt)

3.6 ng/kg (ppt)

5.3 ng/kg (ppt)

0.4 ng/kg (ppt)

1.0 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.4 ng/kg (ppt)

5.0 ng/kg (ppt)

5.0 ng/kg (ppt)

2.0 ng/kg (ppt)

5.0 ng/kg (ppt)

10.0 ng/kg (ppt)

10.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

5.0 ng/kg (ppt)

1.0 ng/kg (ppt)

10.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

10.0 ng/kg (ppt)

0.5 ng/kg (ppt)

5.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

10.0 ng/kg (ppt)

20.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)
The National Study of Chemical Residues in Lake Fish Tissue

Appendix B: Target Chemicals

B-3

Chemical

Group/

 Method Chemicals

CAS

Number

Method

Detection Limit

(MDL)1

Minimum

Level (ML) 

(Quantitation

Limit)1

PCBs 

Method 1668A

(126 individual 

congeners plus 

33 congener 

groups of 2 to 

6 congeners)

(continued)

PCB-112

PCB-114

PCB-118

PCB-120

PCB-121

PCB-122

PCB-123

PCB-126

PCB-127

PCB-128+166

PCB-129+138+160+163

PCB-130

PCB-131

PCB-132

PCB-133

PCB-134+143

PCB-135+151+154

PCB-136

PCB-137

PCB-139+140

PCB-141

PCB-142

PCB-144

PCB-145

PCB-146

PCB-147+149

PCB-148

PCB-150

PCB-152

PCB-153+168

PCB-155

PCB-156+157

PCB-158

PCB-159

PCB-161

PCB-162

PCB-164

PCB-165

PCB-167

PCB-169

PCB-170

PCB-171+173

PCB-172

PCB-174

PCB-175

PCB-176

0.6 ng/kg (ppt)

0.4 ng/kg (ppt)

4.9 ng/kg (ppt)

0.5 ng/kg (ppt)

0.6 ng/kg (ppt)

0.3 ng/kg (ppt)

1.1 ng/kg (ppt)

5.1 ng/kg (ppt)

0.5 ng/kg (ppt)

3.7 ng/kg (ppt)

5.4 ng/kg (ppt)

0.4 ng/kg (ppt)

0.6 ng/kg (ppt)

0.8 ng/kg (ppt)

0.5 ng/kg (ppt)

0.8 ng/kg (ppt)

4.0 ng/kg (ppt)

0.6 ng/kg (ppt)

0.4 ng/kg (ppt)

0.8 ng/kg (ppt)

0.7 ng/kg (ppt)

0.5 ng/kg (ppt)

0.7 ng/kg (ppt)

0.5 ng/kg (ppt)

0.4 ng/kg (ppt)

0.6 ng/kg (ppt)

0.6 ng/kg (ppt)

0.4 ng/kg (ppt)

0.4 ng/kg (ppt)

4.1 ng/kg (ppt)

0.3 ng/kg (ppt)

0.5 ng/kg (ppt)

0.4 ng/kg (ppt)

0.4 ng/kg (ppt)

0.5 ng/kg (ppt)

0.4 ng/kg (ppt)

0.3 ng/kg (ppt)

0.4 ng/kg (ppt)

0.2 ng/kg (ppt)

0.3 ng/kg (ppt)

5.0 ng/kg (ppt)

0.8 ng/kg (ppt)

0.5 ng/kg (ppt)

0.6 ng/kg (ppt)

0.6 ng/kg (ppt)

0.5 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

10.0 ng/kg (ppt)

20.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

10.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

10.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)
B-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix B: Target Chemicals

Chemical

Group/

 Method Chemicals

CAS

Number

Method

Detection Limit

(MDL)1

Minimum

Level (ML) 

(Quantitation

Limit)1

PCBs 

Method 1668A

(126 individual 

congeners plus 

33 congener 

groups of 2 to 

6 congeners)

(continued)

PCB-177

PCB-178

PCB-179

PCB-180+193

PCB-181

PCB-182

PCB-183+185

PCB-184

PCB-186

PCB-187

PCB-188

PCB-189

PCB-190

PCB-191

PCB-192

PCB-194

PCB-195

PCB-196

PCB-197+200

PCB-198+199

PCB-201

PCB-202

PCB-203

PCB-204

PCB-205

PCB-206

PCB-207

PCB-208

PCB-209

0.3 ng/kg (ppt)

0.8 ng/kg (ppt)

0.4 ng/kg (ppt)

4.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.8 ng/kg (ppt)

1.1 ng/kg (ppt)

0.6 ng/kg (ppt)

0.7 ng/kg (ppt)

4.3 ng/kg (ppt)

4.6 ng/kg (ppt)

0.4 ng/kg (ppt)

0.3 ng/kg (ppt)

0.5 ng/kg (ppt)

0.3 ng/kg (ppt)

1.1 ng/kg (ppt)

4.9 ng/kg (ppt)

0.8 ng/kg (ppt)

0.8 ng/kg (ppt)

0.8 ng/kg (ppt)

4.9 ng/kg (ppt)

0.5 ng/kg (ppt)

0.8 ng/kg (ppt)

0.9 ng/kg (ppt)

0.5 ng/kg (ppt)

4.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

5.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

10.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

5.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

10.0 ng/kg (ppt)

10.0 ng/kg (ppt)

1.0 ng/kg (ppt)

1.0 ng/kg (ppt)

2.0 ng/kg (ppt)

1.0 ng/kg (ppt)

5.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

20.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

10.0 ng/kg (ppt)

2.0 ng/kg (ppt)

2.0 ng/kg (ppt)

20.0 ng/kg (ppt)

Dioxins/

Furans 2

Method 1613B

(17 chemicals)

2,3,7,8-TCDD

1,2,3,7,8-PeCDD

1,2,3,4,7,8-HxCDD

1,2,3,6,7,8-HxCDD

1,2,3,7,8,9-HxCDD

1,2,3,4,6,7,8-HpCDD

OCDD

2,3,7,8-TCDF

1,2,3,7,8-PeCDF

2,3,4,7,8-PeCDF

1,2,3,4,7,8-HxCDF

1,2,3,6,7,8-HxCDF

1,2,3,7,8,9-HxCDF

2,3,4,6,7,8-HxCDF

1,2,3,4,6,7,8-HpCDF

1,2,3,4,7,8,9-HpCDF

OCDF

1746-01-6

40321-76-4

39227-28-6

57653-85-7

19408-74-3

35822-46-9

3268-87-9

51207-31-9

57117-41-6

57117-31-4

70648-26-9

57117-44-9

72918-21-9

60851-34-5

67562-39-4

55673-89-7

39001-02-0

0.01 ng/kg (ppt)

0.06 ng/kg (ppt)

0.06 ng/kg (ppt)

0.04 ng/kg (ppt)

0.04 ng/kg (ppt)

0.03 ng/kg (ppt)

0.09 ng/kg (ppt)

0.03 ng/kg (ppt)

0.04 ng/kg (ppt)

0.06 ng/kg (ppt)

0.04 ng.kg (ppt)

0.04 ng/kg (ppt)

0.04 ng/kg (ppt)

0.06 ng/kg (ppt)

0.05 ng/kg (ppt)

0.05 ng/kg (ppt)

0.2 ng/kg (ppt)

0.1 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

1.0 ng/kg (ppt)

0.1 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

0.5 ng/kg (ppt)

1.0 ng/kg (ppt)
The National Study of Chemical Residues in Lake Fish Tissue

Appendix B: Target Chemicals

B-5

Chemical

Group/

 Method Chemicals

CAS

Number

Method

Detection Limit

(MDL)1

Minimum

Level (ML) 

(Quantitation

Limit)1

Organochlorine 

Pesticides 3

Method 1656A

(37 chemicals)

2,4’-DDD

2,4’-DDE

2,4’-DDT

4,4’-DDD

4,4’-DDE

4,4’-DDT

53-19-0

3424-82-6

789-02-6

72-54-8

72-55-9

50-29-3

0.38 μg/kg (ppb)

0.52 μg/kg (ppb)

0.74 μg/kg (ppb)

0.66 μg/kg (ppb)

2.178 μg/kg (ppb)

1.814 μg/kg (ppb)

2.0 μg/kg (ppb)

2.0 μg/kg (ppb)

2.0 μg/kg (ppb)

2.0 μg/kg (ppb)

4.0 μg/kg (ppb)

4.0 μg/kg (ppb)

Aldrin

Chlordane, alphaChlordane, gammaDicofol

Dieldrin

Endosulfan I

Endosulfan II

Endosulfan Sulfate

Endrin

Ethalfluralin

Heptachlor

Heptachlor Epoxide

Hexachlorocyclohexane (BHC), alphaHexachlorocyclohexane (BHC), betaHexachlorocyclohexane (BHC), deltaHexachlorocyclohexane (BHC), gammaIsodrin

Kepone

Methoxychlor

Mirex

Nonachlor, cisNonachlor, transOctachlorostyrene

Oxychlordane

Pendimethalin

Pentachloroanisole

Pentachloronitrobenzene

Permethrin I

Permethrin II

Toxaphene

Trifluralin

309-00-2

5103-71-9

5566-34-7

115-32-2

60-57-1

959-98-8

33213-65-9

1031-07-8

72-20-8

55283-68-6

76-44-8

1024-57-3

319-84-6

319-85-7

319-86-8

58-89-9

465-73-6

143-50-0

72-43-5

2385-85-5

5103-73-1

39765-80-5

29082-74-4

26880-48-8

40487-42-1

1825-21-4

82-68-8

61949-76-6

61949-77-7

8001-35-2

1582-09-8

0.38 μg/kg (ppb)

0.82 μg/kg (ppb)

0.488 μg/kg (ppb)

16.24 μg/kg (ppb)

0.44 μg/kg (ppb)

1.22 μg/kg (ppb)

10.3 μg/kg (ppb)

4.16 μg/kg (ppb)

2.86 μg/kg (ppb)

1.67 μg/kg (ppb)

1.79 μg/kg (ppb)

0.52 μg/kg (ppb)

4.7 μg/kg (ppb)

1.13 μg/kg (ppb)

1.5 μg/kg (ppb)

0.606 μg/kg (ppb)

1.58 μg/kg (ppb)

12.23 μg/kg (ppb)

7.106 μg/kg (ppb)

1.52 μg/kg (ppb)

1.95 μg/kg (ppb)

1.48 μg/kg (ppb)

0.83 μg/kg (ppb)

1.94 μg/kg (ppb)

6.21 μg/kg (ppb)

1.312 μg/kg (ppb)

0.76 μg/kg (ppb)

25 μg/kg (ppb)

21 μg/kg (ppb)

20 μg/kg (ppb)

2.98 μg/kg (ppb)

2.0 μg/kg (ppb)

2.0 μg/kg (ppb)

2.0 μg/kg (ppb)

40.0 μg/kg (ppb)

1.0 μg/kg (ppb)

4.0 μg/kg (ppb)

40.0 μg/kg (ppb)

10.0 μg/kg (ppb)

10.0 μg/kg (ppb)

4.0 μg/kg (ppb)

2.0 μg/kg (ppb)

2.0 μg/kg (ppb)

10.0 μg/kg (ppb)

4.0 μg/kg (ppb)

4.0 μg/kg (ppb)

2.0 μg/kg (ppb)

4.0 μg/kg (ppb)

40.0 μg/kg (ppb)

20.0 μg/kg (ppb)

4.0 μg/kg (ppb)

4.0 μg/kg (ppb)

4.0 μg/kg (ppb)

2.0 μg/kg (ppb)

4.0 μg/kg (ppb)

20.0 μg/kg (ppb)

4.0 μg/kg (ppb)

2.0 μg/kg (ppb)

100.0 μg/kg (ppb)

40.0 μg/kg (ppb)

100.0 μg/kg (ppb)

10.0 μg/kg (ppb)

Organophosphate 

Pesticides 

Method 1657A

(9 chemicals )

Chlorpyriphos

Diazinon

Disulfoton

Disulfoton Sulfone

Ethion

Paraoxon

Parathion, EthylTerbufos

Terbufos Sulfone

2921-88-2

333-41-5

298-04-4

2497-06-5

563-12-2

311-45-5

56-38-2

13071-79-9

56070-16-7

59 μg/kg (ppb)

40 μg/kg (ppb)

161 μg/kg (ppb)

275 μg/kg (ppb)

254 μg/kg (ppb)

121 μg/kg (ppb)

125 μg/kg (ppb)

286 μg/kg (ppb)

73 μg/kg (ppb)

200.0 μg/kg (ppb)

100.0 μg/kg (ppb)

500.0 μg/kg (ppb)

1000.0 μg/kg (ppb)

1000.0 μg/kg (ppb)

500.0 μg/kg (ppb)

500.0 μg/kg (ppb)

1000.0 μg/kg (ppb)

200.0 μg/kg (ppb)
B-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix B: Target Chemicals

Chemical

Group/

 Method Chemicals

CAS

Number

Method

Detection Limit

(MDL)1

Minimum

Level (ML) 

(Quantitation

Limit)1

Other 

Semivolatile 

Organics

Method 1625

(40 chemicals)

1,2,4,5-Tetrachlorobenzene

1,2,4-Trichlorobenzene (TCB) 

1,2-Dichlorobenzene

1,3-Dichlorobenzene

1,4-Dichlorobenzene(p)

2,4,5-Trichlorophenol

2,4,6-Tris (1,1-Dimethylethyl) Phenol

3,3'-Dichlorobenzidine

4-Bromophenyl Phenyl Ether

4,4'-Methylene bis (2-Chloroaniline)

Acenaphthene (PAH)

Acenaphthylene

Anthracene (PAH)

Benzo[a]Anthracene (PAH)

Benzo[a]Pyrene (PAH) 

Benzo(b)Fluoranthene (PAH)

Benzo(ghi)Perylene (PAH)

Benzo(j)Fluoranthene (PAH)

Benzo(k)Fluoranthene (PAH)

Bis (2-ethylhexyl) Phthalate

Butyl Benzyl Phthalate

Chrysene (PAH)

Di-n-Butyl Phthalate 

Dibenz[a,h]Anthrancene (PAH)

Diethylstilbestrol (DES)

Fluoranthene (PAH)

Fluorene (PAH)

Hexachlorobenzene

Hexachlorobutadiene

Indeno(1,2,3-cd)Pyrene (PAH)

Naphthalene (PAH)

Nitrobenzene

Nonylphenol 4

Pentachlorobenzene

Pentachlorophenol

Perylene (PAH)

Phenanthrene (PAH)

Phenol

Pyrene (PAH)

Tetrabromobisphenol A

95-94-3

120-82-1

95-50-1

541-73-1

106-46-7

95-95-4

732-26-3

91-94-1

101-55-3

101-14-4

83-32-9

208-96-8

120-12-7

56-55-3

50-32-8

205-99-2

191-24-2

205-82-3

207-08-9

117-81-7

85-68-7

218-01-9

84-74-2

53-70-3

56-53-1

206-44-0

86-73-7

118-74-1

87-68-3

193-39-5

91-20-3

98-95-3

25154-52-3

608-93-5

87-86-5

198-55-0

85-01-8

108-95-2

129-00-0

79-94-7

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

555 μg/kg (ppb)

111 μg/kg (ppb)

222 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

222 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

222 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

222 μg/kg (ppb)

555 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

111 μg/kg (ppb)

5550 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

1665.0 μg/kg (ppb)

333.0 μg/kg (ppb)

666.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

1665.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

666.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

666.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

666.0 μg/kg (ppb)

1665.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

333.0 μg/kg (ppb)

16650.0 μg/kg (ppb)

Notes:

1. See Section 3.1.2 for more information on detection and quantitation limits.

2. Reporting levels for dioxins and furans in this study are ten (10) times lower than the ML specified in Method 1613B.

3. Hexachlorocyclohexane is reported as its individual components: alpha, beta, delta, and gamma BHC. See notation in list.

Note that gamma BHC is also known as Lindane.

4. Nonylphenol is calibrated, calculated, and integrated as a group of nonylphenol isomers, rather than as the single 

4-nonylphenol isomer.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix C

Target Species
The National Study of Chemical Residues in Lake Fish Tissue

Appendix C: Target Species

Common

Name

S

cientifi

c name

Length Range

(mm)

Weight Range

(g)

Numbe

r of

Composites

Percent of

total

Bowfinsbowfin

AmiidaeAmia calva 431 - 525 777 - 1423 2 <1

Garsspotted gar

LepisosteidaeLepisosteus oculatus 385 - 486 217 - 383 1 <1

Perchessaugersaugeyewalleyeyellow perch

PercidaeStizostedion canadense Stizostedion canadense x Stizostedion vitreumStizostedion vitreumPerca flavescens

310 - 360

386 - 601

190 - 685

170 - 346

230 - 403

446 - 2007

51 - 3750

45 - 530

13

49

18

<1

1

10

4

Pikeschain pickerelnorthern pike

EsocidaeEsox nigerEsox lucius

338 - 460

260 - 840

211 - 535

94 - 4425

3

34

17

Sunfishesblack crappiebluegilllargemouth bassrock basssmallmouth bassspotted basswhite crappie

CentrarchidaePomoxis nigromaculatusLepomis macrochirusMicropterus salmoidesAmbloplites rupestrisMicropterus dolomieuMicropterus punctulatusPomoxis annularis

174 - 340

122 - 216

175 - 570

172 - 240

201 - 488

244 - 415

192 - 400

77 - 648

33 - 252

71 - 3200

86 - 319

107 - 1745

152 - 1005

83 - 1010

65

246

2

23

5

13

11

50

<1

513

Temperate bassesstriped basswhite basswhite bass hybridwhite perch

PercichthydaeMorone saxatilisMorone chrysopsMorone spp.Morone americana

394 - 770

253 - 441

325 - 360

253 - 340

574 - 4822

232 - 1253

318 - 463

205 - 702

5525

11

<1

1

TroutsAtlantic salmonbrook troutbrown troutcutthroat troutcutthroat trout x rainbow troutkokaneelake troutlake whitefishmountain whitefishrainbow troutsplakeYellowstone cutthroat trout

SalmonidaeSalmo salarSalvelinus fontinalisSalmo truttaOncorhynchus clarkiOncorhynchus clarki X Oncorhynchus mykissOncorhynchus nerkaSalvelinus namaycushCoregonus clupeaformisProsopium williamsoniOncorhynchus mykissSalvelinus namaycush x Salvelinus fontinalisOncorhynchus clarki bouvieri

310 - 391

189 - 470

199 - 700233 - 588

392 - 436

206 - 243

318 - 825

361 - 465

264 - 356

254 - 434

383 - 445

213 - 271

256 - 526

61 - 1925

91 - 2625

105 - 2370

494 - 684

55 - 87

231 - 4460

454 - 1215

135 - 410

129 - 734

432 - 696

90 - 175

1

12

6

10

11

10

11

14

11

<1

212

<1<1

2

<1<1

3

<1<1

Table C-1.

P

re

d

at

o

r Com

p

o

site Summ

ar

y.

C-1
The National Study of Chemical Residues in Lake Fish Tissue

Appendix C: Target Species

C-2

Common

Name

S

cientifi

c name

Length Range

(mm)

Weight Range

(g)

Numbe

r of

Composites

Percent of

total

Bullhead catfishesblack bullheadblue catfish brown bullheadbullhead catfishchannel catfishflathead catfishwhite catfishyellow bullhead

IctaluridaeAmeiurus melasIctalurus furcatusAmeiurus nebulosusAmeiurus sppIctalurus punctatusPylodictis olivarisAmeiurus catusAmeiurus natalis

135 - 385

340 - 708

169 - 430

325 - 405

255 - 750

345 - 545

254 - 345

200 - 400

20 - 920

253 - 4798

54 - 1071

533 - 1152

119 - 5575

336.5 - 1550

219 - 490

107 - 870

19

6

30

2

64

32

23

5281

16

116

Carps and 

Minnows

common carpgoldfishgrass carp

CyprinidaeCyprinus carpioCarassius auratusCtenopharyngodon idella

255 - 765

324 - 410

505 - 850

244 - 7821

760 - 1769

1627 - 10005

104

22

26

11

Drumsfreshwater drum

SciaenidaeAplodinotus grunniens 308 - 445 346 - 959 3 1

Suckersblack redhorseblacktail redhorsebuffalocreek chubsuckergolden redhorselake chubsuckerlargescale suckerlongnose suckernorthern redhorse suckerredhorse suckerSacramento suckershorthead redhorsesilver redhorsesmallmouth buffalospotted suckerUtah suckerwhite sucker

CatostomidaeMoxostoma duquesneiMoxostoma poecilurumIctiobus spp.Erimyzon oblongusMoxostoma erythrurumErimyzon sucettaCatostomus macrocheilusCatostomus catostomusMoxostoma spp.Moxostoma spp.Catostomus occidentalisMoxostoma macrolepidotumMoxostoma anisurumIctiobus bubalusMinytrema melanopsCatostomus ardensCatostomus commersoni

337 - 343

320 - 375

490 - 565

270 - 310

360 - 384

215 - 378

380 - 558

323 - 420

371 - 402

314 - 339

352 - 468

234 - 276

270 - 564

381 - 680

320 - 526

353 - 528

213 - 570

366 - 426

329 - 497

2609 - 3571

290 - 450

536 - 647

116 - 829

473 - 2097

292 - 757

535 - 737

319 - 427

996 - 1183

125 - 205

210 - 2000

770 - 5111

439 - 1761

422 - 1997

99 - 2200

1111198311213

11

54

81

<1<1<1<1<1

221

<1<1

1

<1

1311

20

Table C-2.

B

o

tt

om-dw

eller Com

p

o

site Summ

ar

y.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix C: Target Species

C-3
The National Study of Chemical Residues in Lake Fish Tissue

Appendix D

Analytical Methods

The National Study of Chemical Residues in Lake Fish Tissue

Appendix D: Analytical Methods

D-1

Analytical Methods

Mercury (Total) by EPA Method 1631B 

Total mercury (Hg) concentrations were determined by EPA Method 1631, Revision B 

(Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence 

Spectrometry) and its Appendix (Digestion Procedures for the Determination of Total 

Mercury in Tissue, Sludge, Sediment, and Soil).

Analysis of total mercury in fish tissue samples by Method 1631B involved the following 

steps: 

1) digesting 0.5 g to 1.5 g of tissue sample and refluxing with 10 mL of concentrated 

nitric acid, 

2) diluting the digestate to volume (50 or 100 mL) with 0.02N BrCl to ensure complete 

oxidation of methylmercury, 

3) pipetting aliquots of the diluted digestate into pre-purged SnCl2-containing water, 

4) purging Hg(0) from solution onto a gold trap, and 

5) thermally desorbing Hg(0) from the gold trap and transferring it to a cold vapor atomic 

fluorescence spectrometer for quantification. 

The chemical concentration in the fish tissue sample was calculated on a mass basis 

(i.e., relative to the mass of the sample extracted).

Arsenic by EPA Method 1632A

Total inorganic arsenic, arsenic (III), monomethylarsonic acid (MMA), and dimethylarsinic 

acid (DMA) were directly determined by EPA Method 1632, Revision A (Chemical Speciation 

of Arsenic in Water and Tissue using Hydride Generation Quartz Furnace Atomic Absorption Spectrometry). Arsenic (V) was determined by mathematically subtracting the measured 

concentration of arsenic (III) from the measured concentration of total inorganic arsenic. 

Total arsenic (which includes organic forms such as arsenobetaine) was not measured.

Analysis of the fish tissue samples by Method 1632A involved the following steps: 

1) volatilizing Arsenic (III), arsenic (V), MMA, and DMA from solution at a specific pH 

after reduction to the corresponding arsines with sodium borohydride, 

2) sweeping the volatilized arsines onto a liquid nitrogen cooled chromatographic trap 

which, upon warming, allows for a separation of species based on boiling points,

3) sweeping the released arsines by helium carrier gas into a quartz cuvette burner cell, 

where they are decomposed to atomic arsenic, and 

4) determining arsenic concentrations by atomic absorption spectroscopy. 

Strictly speaking, this technique determines the valence states of arsenate (V) and arsenite 

(III) rather than the species of inorganic arsenic. The actual species of inorganic arsenic are 

assumed to be those predicted by a geochemical equilibrium model.
D-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix D: Analytical Methods

Polychlorinated Biphenyls (PCBs) by EPA Method 1668A

EPA Method 1668, Revision A (Chlorinated Biphenyls Congeners in Water, Soil, Sediment, 

and Tissue by HRGC/HRMS, EPA-821-R-00-002) was used to determine PCB congener 

concentrations in tissue samples collected during the study. There are 209 possible 

congeners, 12 of which have toxicological significance (i.e., the “toxic” PCBs identified 

by the World Health Organization). Method 1668A can unambiguously determine 126 

of the 209 congeners as separate chromatographic peaks. The remaining 83 congeners do 

not appear as separate peaks, but elute from the gas chromatograph in groups of 2 to 6 

congeners that cannot be completely resolved by the instrumentation. Ten of the 12 “toxic” 

congeners are resolved, and the remaining two congeners (PCB 156 and PCB 157) elute 

as a congener pair. Because PCB 156 and 157 have identical toxicity equivalency factors, 

however, it is possible to accurately calculate PCB toxic equivalence based on the 12 toxic 

congeners.

Analysis of the full complement of PCB congeners in fish tissue samples by Method 1668A 

involved the following steps: 

1) drying a 10-g aliquot of a homogenized fish tissue sample with sodium sulfate, 

2) spiking the dried fish sample with a labeled standard solution, 

3) performing soxhlet extraction of the dried fish sample using 1:1 methylene chloride/

hexane as the extraction solvent, 

4) drying the extract with sodium sulfate and concentrating the extract to dryness (to 

measure lipid content) using Kuderna-Danish and nitrogen blow-down techniques, 

5) re-dissolving the extract and removing lipids by passing the extract through a layered 

column of silica gel, potassium silicate, and acid silica gel, 

6) completing further clean-up of the extract using back-extraction with a strong base, 

acid and/or sodium chloride solution, gel-permeation chromatography, silica gel, 

carbon, or Florisil chromatography, 

7) re-concentrating the extract using Kuderna-Danish and nitrogen blow-down 

techniques, and 

8) quantifying the target chemicals in the extract using a gas chromatograph equipped 

with a high-resolution mass spectrometer. 

The target chemicals were identified by comparing their chromatographic retention times 

with those of authentic standards and by comparing the ratio of the abundance of two ions 

specific to each chemical with the theoretical ion abundance ratio for that chemical. Concentrations were calculated from selected ion current profile areas using either an isotope dilution or internal standard technique. The efficiency of the clean-up process was monitored by 

spiking the extract prior to clean-up with labeled standards (PCBs 81 and 111) and tracking 

the final recovery of these standards. The chemical concentration in the fish tissue sample 

can be calculated on a mass basis (i.e., relative to the mass of the sample extracted), or lipid 

basis (i.e., relative to the lipid content of the sample extracted).
The National Study of Chemical Residues in Lake Fish Tissue

Appendix D: Analytical Methods

D-3

Dioxins and Furans by EPA Method 1613B

The presence and concentration of seventeen 2,3,7,8-substituted chlorinated dibenzo-pdioxins and dibenzofurans in each sample was determined by a slightly modified version 

of EPA Method 1613, Revision B (Tetra- through Octa- Chlorinated Dioxins and Furans 

by Isotope Dilution HRGC/HRMS, EPA-821-B-94-005). Modifications were made to the 

procedures in order to allow for determination of dioxins and furans at levels ten times 

lower than those specified in the method. Specifically, the method was modified to increase 

the tissue sample size used for analysis and to add a sixth calibration solution that contained 

all the method-specified chemicals at levels lower than the levels specified in the method to 

verify linearity at the lower concentrations targeted.

Determination of dioxins and furans in tissue samples by Method 1613B involved the 

following steps: 

1) drying a 100-g aliquot of a homogenized fish tissue sample with sodium sulfate, 

2) spiking the dried fish sample with a labeled standard solution, 

3) preparing extracts either by soxhlet extraction using 1:1 methylene chloride/hexane as 

the extraction solvent or by acid digestion using hydrochloric acid and 1:1 methylene 

chloride/hexane, 

4) drying with sodium sulfate and concentrating the extract to dryness (to measure lipid 

content) using Kuderna-Danish and nitrogen blow-down techniques, 

5) re-dissolving the extract and removing lipids by passing the extract through a layered 

column of silica gel, potassium silicate, and acid silica gel, 

6) completing further clean-up of the extract using back-extraction with a strong base, 

acid and/or sodium chloride solution, gel-permeation chromatography, silica gel, 

alumina, or Florisil chromatography, 

7) re-concentrating the extract using Kuderna-Danish and nitrogen blow-down 

techniques, and 

8) quantifying the target chemicals in the extract using a gas chromatograph equipped 

with a high-resolution mass spectrometer. 

The target chemicals were identified by comparing their chromatographic retention times 

with those of authentic standards and by comparing the ratio of the abundance of two 

ions specific to each chemical with the theoretical ion abundance ratio for that chemical. 

Concentrations were calculated from selected ion current profile areas using either an 

isotope dilution or internal standard technique. The efficiency of the clean-up process was 

monitored by spiking the extract prior to clean-up with a labeled standard (37Cl4- labeled 

2,3,7,8 TCDD) and tracking the final recovery of this standard. The chemical concentration 

in the fish tissue sample can be calculated on a mass basis (i.e., relative to the mass of the 

sample extracted), or lipid basis (i.e., relative to the lipid content of the sample extracted).

For more information on this Method, visit www.epa.gov/waterscience/methods/1613.pdf.
D-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix D: Analytical Methods

Organochlorine Pesticides by EPA Method 1656A

Organochlorine pesticides (e.g., DDT and chlordane) and were determined by Method 1656, 

Revision A (Organo-Halide Pesticides in Wastewater, Soil, Sludge, Sediment, and Tissue by 

GC/HSD). The following modification was made to the procedure listed below: the tissue 

sample extracts were concentrated by a factor of five beyond method-specified levels before 

instrumental analysis. This modification ensured that all target pesticides could be quantified at levels equal to or lower than the human health screening values for recreational fishers published in Table 5-3 of EPA’s Guidance for Assessing Chemical Contaminant Data for 

Use in Fish Advisories, Volume 1: Risk Assessment and Fish Consumption Limits, Third 

Edition (EPA 2000d).

Analysis of the target pesticides in fish tissue samples by Method 1656A involved the 

following steps: 

1) drying a 10-g aliquot of a homogenized fish tissue sample with sodium sulfate, 

2) preparing a soxhlet extraction of the dried fish sample using 1:1 methylene chloride/

hexane as the extraction solvent, 

3) drying the extract with sodium sulfate and concentrating the extract to dryness (to 

measure lipid content) using Kuderna-Danish and nitrogen blow-down techniques, 

4) re-dissolving the extract and removing lipids by gel-permeation chromatography and/or 

solid-phase extraction (SPE cartridges), 

5) re-concentrating the extract using Kuderna-Danish and nitrogen blow-down 

techniques, and 

6) quantifying the target chemicals in the extract using a gas chromatograph equipped 

with dual capillary columns and an electron capture detector. 

Target chemical identification is performed by comparing the GC retention times of each 

chemical on two different columns with the respective retention times of an authentic 

standard. Quantitative analysis (e.g., determining the concentration of each chemical) was 

performed using an authentic standard to produce a calibration factor or calibration curve, 

and using the calibration data to determine the concentration of a pollutant in the extract. 

The chemical concentration in the fish tissue sample can be calculated on a mass basis 

(i.e., relative to the mass of the sample extracted), or lipid basis (i.e., relative to the lipid 

content of the sample extracted).
The National Study of Chemical Residues in Lake Fish Tissue

Appendix D: Analytical Methods

D-5

Organophosphorus Pesticides by EPA Method 1657A

EPA Method 1657, Revision A (Organophosphorus Pesticides in Water, Soil, and Tissue 

by GC/FPD) was used to determine the presence and concentration of organophosphorus 

pesticides (e.g., chlorpyrifos and diazinon).

Analysis of the fish tissue samples by Method 1657A involved the following steps: 

1) drying a 10-g aliquot of a homogenized fish tissue sample with sodium sulfate, 

2) preparing a soxhlet extraction of the dried fish sample using 1:1 methylene chloride/

hexane as the extraction solvent, 

3) drying the extract with sodium sulfate and concentrating the extract to dryness (to 

measure lipid content) using Kuderna-Danish and nitrogen blow-down techniques, 

4) re-dissolving the extract and removing lipids by gel-permeation chromatography and/or 

solid-phase extraction (SPE cartridges), 

5) re-concentrating the extract using Kuderna-Danish and nitrogen blow-down 

techniques, and 

6) quantifying the target chemicals in the extract using a gas chromatograph equipped 

with dual capillary columns and a flame photometric detector. 

Target chemical identification was performed by comparing the GC retention times of 

each chemical on two different columns with the respective retention times of an authentic 

standard. Quantitative analysis (e.g., determining the concentration of each chemical) was 

performed using an authentic standard to produce a calibration factor or calibration curve, 

and using the calibration data to determine the concentration of a chemical in the extract. 

The chemical concentration in the fish tissue sample can be calculated on a mass basis 

(i.e., relative to the mass of the sample extracted), or lipid basis (i.e., relative to the lipid 

content of the sample extracted).
D-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix D: Analytical Methods

Semivolatile Organic Chemicals by Method 1625C

The remainder of the target organic chemicals were analyzed by a modified version of EPA 

Method 1625, Revision C (Semivolatile Organic Compounds by Isotope Dilution GC/MS). 

The modifications made to this method involved fractionating the samples by gel permeation 

chromatography (GPC) to yield a fraction containing the phthalates and some of the lower 

molecular weight lipids and a lipid-free fraction containing the polar target compounds. The 

phthalate/lipid fraction was further cleaned using Alumina and then recombined with the 

lipid-free fraction so that all target chemicals could be determined in a single run. 

Analysis of the target chemicals by Method 1625C involved the following steps: 

1) homogenizing and spiking isotopically labeled analogs of each target chemical into the 

sample, 

2) extracting the sample at pH 12-13 and then at pH <2 with methylene chloride using 

continuous extraction techniques, 

3) drying each extract over sodium sulfate, 

4) concentrating the extract to five mL, 

5) cleaning the extract with gel permeation chromatography, 

6) concentrating the extract to 0.5 mL, 

7) adding internal standards to the extract, and 

8) injecting a one μL aliquot of the extract into a gas chromatograph (GC). 

At this point, the target chemicals are separated by GC and detected by a mass spectrometer 

(MS). The labeled compounds serve to correct the variability of the analytical technique. 

Chemical identification was performed by comparing mass spectrum and retention time 

to calibration standards (for most chemicals) or through reference libraries using forward 

search or reverse search techniques. Quantitative analysis was performed in one of the 

following ways using extracted ion current profile (EICP) areas: 

n for compounds in which standards and labeled analogs were available, the 

concentration was determined using isotope dilution techniques,

n for compounds in which standards were available but labeled analogs were not, the 

concentration was determined using an internal standard technique, and

n for compounds in which neither standards nor known response factors were available, 

concentrations were determined using the sum of the EICP areas relative to the sum of 

the EICP areas of the internal standard.

During analysis of the samples collected in the fourth year of the study only, the laboratory 

employed a Florisil cleanup instead of an Alumina cleanup. This change was initiated to 

mitigate lipid interferences that were resulting in an excessive number of re-extractions and 

re-analyses in the samples collected during previous years of the study. The use of Florisil 

did reduce the number of re-analyses required, suggesting that this approach should be 

considered in any further studies.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E

Percentile Tables 

for Detected Target Chemicals

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-1

Ta

b

le E-1.

Metals

Tissue Concentration Estimates for Predators (Fillets)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Mercury

Mercury 486 486 6605 ppb 59.17 89.33 176.67 284.60 432.08 561.79 833.41

Arsenic

Arsenate 486 2 0.035 ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Arsenite 486 0 Not Applicable ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Inorganic Arsenic (Total)

486 2 0.035 ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Dimethylarsonic Acid 486 4 0.107 ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Monomethylarsonic Acid

486 6 0.016 ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Mercury

Mercury 395 395 596 ppb 18.61 20.10 39.27 68.56 124.17 219.58 247.31

Arsenic

Arsenate 395 4 0.117 ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Arsenite 395 61 0.464 ppm < MDL < MDL < MDL < MDL < MDL 0.03 0.05

Inorganic Arsenic (Total)

395 36 0.275 ppm < MDL < MDL < MDL < MDL < MDL < MDL 0.04

Dimethylarsonic Acid 395 9 0.054 ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Monomethylarsonic Acid

395 0 Not Applicable ppm < MDL < MDL < MDL < MDL < MDL < MDL < MDL
E-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners

Tissue Concentration Estimates for Predators (Fillets)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 1 486 32 7 ppt < MDL < MDL < MDL < MDL < MDL < MDL 0.83

PCB 2 486 8 3 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 3 486 131 8 ppt < MDL < MDL < MDL < MDL 0.90 1.77 2.22

PCB 4 486 213 266 ppt < MDL < MDL < MDL < MDL 0.71 1.89 5.75PCB 5 486 4 4 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 6 486 172 401 ppt < MDL < MDL < MDL < MDL 0.28 0.87 2.09

PCB 7 486 92 11 ppt < MDL < MDL < MDL < MDL 0.14 0.81 2.11

PCB 8 486 174 467 ppt < MDL < MDL < MDL < MDL 1.51 4.14 8.65

PCB 9 486 37 28 ppt < MDL < MDL < MDL < MDL < MDL < MDL 0.59

PCB 10 486 15 9 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 11 486 264 185 ppt < MDL < MDL < MDL 1.02 1.46 2.57 4.51PCB 12 + PCB 13 486 14 20 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 14 486 1 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 15 486 258 820 ppt < MDL < MDL < MDL 0.17 0.70 1.93 3.47PCB 16 486 287 298 ppt < MDL < MDL < MDL < MDL 1.71 3.82 12.65

PCB 17 486 339 487 ppt < MDL < MDL < MDL 1.02 2.19 8.20 23.85

PCB 18 + PCB 30 486 370 1470 ppt < MDL < MDL < MDL 2.29 4.57 14.31 37.52

PCB 19 486 287 142 ppt < MDL < MDL < MDL 0.11 0.39 1.53 2.33

PCB 20 + PCB 28 486 428 7910 ppt < MDL < MDL 4.78 8.60 21.90 72.20 163.61

PCB 21 + PCB 33 486 401 699 ppt < MDL < MDL < MDL 1.64 3.41 10.11 24.50PCB 22 486 439 584 ppt < MDL < MDL 0.81 1.84 4.94 14.73 36.04

PCB 23 486 8 2 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 24 486 31 16 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-3

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for Predators (Fillets) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 25 486 262 200 ppt < MDL < MDL < MDL < MDL 0.96 3.94 7.24

PCB 26 + PCB 29 486 146 577 ppt < MDL < MDL < MDL < MDL < MDL 7.94 17.04

PCB 27 486 140 136 ppt < MDL < MDL < MDL < MDL < MDL 1.46 3.62

PCB 31 486 434 2020 ppt < MDL < MDL 2.63 4.88 12.76 45.26 79.92PCB 32 486 286 282 ppt < MDL < MDL < MDL < MDL 1.07 3.04 7.77

PCB 34 486 72 27 ppt < MDL < MDL < MDL < MDL < MDL 0.19 0.99

PCB 35 486 1 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 36 486 2 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 37 486 438 1170 ppt < MDL < MDL 0.37 0.84 2.33 5.32 9.43

PCB 38 486 22 7 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 39 486 52 12 ppt < MDL < MDL < MDL < MDL < MDL < MDL 0.76PCB 40 + PCB 41 + PCB 71

486 407 1690 ppt < MDL < MDL < MDL 2.84 10.33 32.62 72.78

PCB 42 486 455 1230 ppt < MDL < MDL 1.05 2.61 6.99 25.88 59.03PCB 43 486 151 96 ppt < MDL < MDL < MDL < MDL < MDL 3.33 6.86

PCB 44 + PCB 47 + PCB 65

486 452 10700 ppt < MDL < MDL 5.71 13.17 39.33 123.13 271.61

PCB 45 + PCB 51 486 190 327 ppt < MDL < MDL < MDL < MDL < MDL 6.44 15.49

PCB 46 486 93 97 ppt < MDL < MDL < MDL < MDL < MDL 1.18 2.68

PCB 48 486 389 405 ppt < MDL < MDL < MDL 1.30 3.75 11.53 22.65PCB 49 + PCB 69 486 478 9940 ppt 1.58 2.33 4.03 9.62 27.09 104.02 211.89

PCB 50 + PCB 53 486 123 678 ppt < MDL < MDL < MDL < MDL < MDL 4.92 10.38

PCB 52 486 469 12500 ppt < MDL < MDL 8.18 18.67 52.45 214.56 380.53

PCB 54 486 34 15 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL
E-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for Predators (Fillets) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 55 486 63 81 ppt < MDL < MDL < MDL < MDL < MDL < MDL 0.86

PCB 56 486 467 1230 ppt < MDL 0.70 1.93 4.90 13.71 46.11 67.74

PCB 57 486 113 57 ppt < MDL < MDL < MDL < MDL < MDL 1.21 2.06

PCB 58 486 131 71 ppt < MDL < MDL < MDL < MDL < MDL 1.15 2.50

PCB 59 + PCB 62 + PCB 75

486 286 480 ppt < MDL < MDL < MDL < MDL 3.85 14.02 30.82

PCB 60 486 479 1560 ppt 0.60 0.80 1.98 4.37 15.03 45.82 71.90PCB 61 + PCB 70 + PCB 74 + PCB 76

486 485 11700 ppt 4.83 7.28 16.35 35.35 101.65 338.62 617.78

PCB 63 486 405 616 ppt < MDL < MDL < MDL 1.51 3.77 13.99 25.67

PCB 64 486 484 2320 ppt 0.90 1.48 2.56 6.26 17.07 57.64 119.54

PCB 66 486 460 8000 ppt < MDL 5.37 10.75 26.64 66.25 265.50 467.23

PCB 67 486 295 131 ppt < MDL < MDL < MDL < MDL 1.52 5.18 8.05

PCB 68 486 378 317 ppt < MDL < MDL < MDL 0.69 1.46 5.53 8.80

PCB 72 486 325 389 ppt < MDL < MDL < MDL 0.54 1.42 6.25 10.34

PCB 73 486 20 78.4 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 77 486 181 275 ppt < MDL < MDL < MDL < MDL 5.01 14.03 22.03

PCB 78 486 1 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 79 486 284 458 ppt < MDL < MDL < MDL < MDL 1.99 8.17 11.81PCB 80 486 2 11 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 81 486 104 28 ppt < MDL < MDL < MDL < MDL < MDL 0.49 1.36

PCB 82 486 456 1890 ppt < MDL < MDL 1.00 2.90 10.55 38.89 65.48PCB 83 + PCB 99 486 484 24300 ppt 10.03 14.32 33.79 67.91 240.62 765.55 1277.17

PCB 84 486 449 2320 ppt < MDL < MDL 0.97 3.02 10.01 31.61 85.04
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-5

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for Predators (Fillets) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 85 + PCB 116 + PCB 117

486 485 7980 ppt 2.84 3.81 8.76 17.97 64.98 179.65 300.95

PCB 86 + PCB 87 + PCB 97 + PCB 108 + PCB 119 + PCB 125

486 476 18900 ppt 1.96 6.86 14.89 37.03 126.15 418.07 660.55

PCB 88 + PCB 91 486 469 4770 ppt < MDL 0.77 1.72 4.33 14.31 73.43 113.10

PCB 89 486 121 22.3 ppt < MDL < MDL < MDL < MDL < MDL 0.76 1.26

PCB 90 + PCB 101 + PCB 113

486 484 36500 ppt 10.30 15.72 38.92 80.10 262.84 884.10 1420.95

PCB 92 486 481 8620 ppt 1.83 2.94 6.99 15.23 54.77 187.79 303.98

PCB 93 + PCB 95 + PCB 98 + PCB 100 + PCB 102

486 470 17200 ppt 2.21 3.56 7.68 17.54 68.54 208.27 416.02

PCB 94 486 76 62 ppt < MDL < MDL < MDL < MDL < MDL < MDL 0.85

PCB 96 486 47 31 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 103 486 326 365 ppt < MDL < MDL < MDL 0.41 1.38 6.82 11.34

PCB 104 486 1 4 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 105 486 470 12100 ppt 5.61 7.72 16.65 36.93 120.78 285.44 536.10

PCB 106 486 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 107 + PCB 124 486 449 1430 ppt < MDL < MDL 1.71 3.88 13.09 31.21 58.52

PCB 109 486 478 4090 ppt 1.19 2.04 5.05 10.46 34.83 88.70 152.94

PCB 110 + PCB 115 486 485 31800 ppt 6.51 10.95 25.72 52.96 203.68 684.32 1095.40

PCB 111 486 214 90 ppt < MDL < MDL < MDL < MDL 0.63 1.57 3.31

PCB 112 486 1 40 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 114 486 458 950 ppt < MDL < MDL 0.82 1.92 8.23 18.91 33.90

PCB 118 486 483 26300 ppt 15.39 24.78 50.19 108.39 367.92 976.25 1790.44
E-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for Predators (Fillets) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 120 486 407 392 ppt < MDL < MDL 0.62 1.39 4.31 11.00 16.28PCB 121 486 105 85 ppt < MDL < MDL < MDL < MDL < MDL 0.61 1.30

PCB 122 486 281 74 ppt < MDL < MDL < MDL 0.40 2.51 5.80 8.88

PCB 123 486 400 764 ppt < MDL < MDL < MDL 2.38 7.20 18.39 31.06

PCB 126 486 51 296 ppt < MDL < MDL < MDL < MDL < MDL < MDL 5.57

PCB 127 486 174 97 ppt < MDL < MDL < MDL < MDL 0.08 1.94 4.49PCB 128 + PCB 166 486 477 12500 ppt 5.01 7.33 14.64 30.83 101.87 259.56 496.43

PCB 129 + PCB 138 + PCB 160 + PCB 163

486 485 91600 ppt 35.77 55.98 103.72 247.24 859.74 1908.97 3487.52

PCB 130 486 481 4360 ppt 1.55 1.87 5.43 11.18 33.93 98.55 177.30

PCB 131 486 315 272 ppt < MDL < MDL < MDL < MDL 2.18 7.99 12.04

PCB 132 486 485 9020 ppt 1.21 1.90 4.27 10.51 42.80 165.36 293.00

PCB 133 486 476 1940 ppt 0.75 1.03 2.13 4.59 13.09 36.60 60.17PCB 134 + PCB 143 486 434 1530 ppt < MDL < MDL 0.92 2.11 8.56 27.22 40.55PCB 135 + PCB 151 + PCB 154

486 472 13000 ppt 3.87 5.82 13.46 30.00 83.78 262.98 612.12

PCB 136 486 435 2670 ppt < MDL < MDL < MDL 1.65 7.02 29.84 76.80

PCB 137 486 480 4190 ppt 1.32 1.93 4.53 9.97 39.19 75.26 149.88

PCB 139 + PCB 140 486 445 1260 ppt < MDL < MDL 1.46 3.07 10.50 29.31 61.34

PCB 141 486 485 9440 ppt 3.22 4.97 10.38 22.45 85.87 242.08 362.95

PCB 142 486 1 14 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 144 486 444 1290 ppt < MDL < MDL 1.20 3.67 13.97 36.80 80.89PCB 145 486 7 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 146 486 485 18100 ppt 7.69 11.91 23.48 49.74 194.63 417.63 649.23
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-7

Ta

b

le E-2.

P

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Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for Predators (Fillets) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 147 + PCB 149 486 483 25500 ppt 8.82 12.68 26.44 59.54 206.12 716.30 1294.18PCB 148 486 253 143 ppt < MDL < MDL < MDL < MDL 1.09 3.20 8.41

PCB 150 486 174 50 ppt < MDL < MDL < MDL < MDL < MDL 1.05 2.77

PCB 152 486 37 21 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 153 + PCB 168 486 485 101000 ppt 44.73 63.16 125.97 284.22 984.90 2225.10 4059.53PCB 155 486 199 417 ppt < MDL < MDL < MDL < MDL 0.20 0.88 2.38PCB 156 + PCB 157 486 483 7640 ppt 3.24 4.38 9.54 19.92 73.05 166.30 299.28PCB 158 486 484 5190 ppt 2.90 3.92 8.41 18.09 61.08 152.97 239.37

PCB 159 486 398 277 ppt < MDL < MDL < MDL 0.94 2.46 10.63 16.14

PCB 161 486 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 162 486 410 723 ppt < MDL < MDL 0.54 1.52 5.01 10.60 15.77

PCB 164 486 480 3070 ppt 1.20 1.55 3.67 8.04 23.91 71.99 136.55

PCB 165 486 170 108 ppt < MDL < MDL < MDL < MDL 0.21 1.19 1.97

PCB 167 486 482 3540 ppt 1.60 2.72 5.05 10.69 34.19 83.32 143.99

PCB 169 486 103 70 ppt < MDL < MDL < MDL < MDL < MDL 0.36 0.92

PCB 170 486 473 18200 ppt 6.89 12.50 22.85 45.53 154.78 415.39 819.93PCB 171 + PCB 173 486 480 4920 ppt 1.88 3.29 6.04 12.88 44.81 141.13 216.60

PCB 172 486 480 5540 ppt 1.90 2.85 6.47 13.17 44.07 104.81 187.30

PCB 174 486 483 5490 ppt 2.01 2.32 6.83 19.83 55.67 203.52 285.75

PCB 175 486 435 1040 ppt < MDL < MDL 0.99 2.49 9.01 24.54 36.04PCB 176 486 412 580 ppt < MDL < MDL < MDL 0.92 3.83 17.08 30.17

PCB 177 486 484 11100 ppt 1.90 2.41 7.88 18.22 50.06 187.04 314.28

PCB 178 486 481 6540 ppt 1.86 2.30 6.45 13.84 32.59 118.27 197.31
E-8

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for Predators (Fillets) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 179 486 466 2170 ppt < MDL 0.22 1.22 3.51 13.77 52.13 120.61PCB 180 + PCB 193 486 483 55800 ppt 20.52 34.49 65.54 137.70 457.03 1350.45 2146.57

PCB 181 486 308 255 ppt < MDL < MDL < MDL 0.09 2.04 4.51 8.08

PCB 182 486 326 494 ppt < MDL < MDL < MDL 0.84 3.05 8.49 13.48

PCB 183 + PCB 185 486 478 14800 ppt 5.31 9.98 18.13 38.14 132.23 397.73 618.98

PCB 184 486 213 536 ppt < MDL < MDL < MDL < MDL 0.71 1.87 3.62PCB 186 486 1 4 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 187 486 483 39700 ppt 18.55 26.49 47.22 109.52 341.65 1058.04 1407.33

PCB 188 486 49 207 ppt < MDL < MDL < MDL < MDL < MDL < MDL 5.87

PCB 189 486 447 978 ppt < MDL 0.49 1.12 2.26 7.03 19.71 27.67

PCB 190 486 481 4290 ppt 1.77 3.02 5.56 12.41 36.40 94.99 215.13PCB 191 486 436 646 ppt < MDL < MDL 0.90 1.96 6.79 18.89 37.26

PCB 192 486 17 30 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 194 486 482 9780 ppt 4.21 6.85 14.15 30.29 90.97 290.49 397.81

PCB 195 486 390 2900 ppt < MDL < MDL < MDL 10.35 30.60 96.29 153.79

PCB 196 486 479 5650 ppt 2.41 3.62 8.00 16.80 54.96 174.55 205.69

PCB 197 + PCB 200 486 435 783 ppt < MDL < MDL 1.16 2.56 7.81 21.78 42.31

PCB 198 + PCB 199 486 485 16100 ppt 7.09 11.22 20.78 46.92 136.26 360.44 725.42

PCB 201 486 296 1930 ppt < MDL < MDL < MDL < MDL 11.97 37.56 68.67

PCB 202 486 471 4250 ppt < MDL 1.73 4.52 8.83 22.75 75.08 116.91

PCB 203 486 481 9480 ppt 4.94 6.98 13.94 30.24 91.06 278.36 388.84

PCB 204 486 67 72 ppt < MDL < MDL < MDL < MDL < MDL < MDL 1.72PCB 205 486 424 666 ppt < MDL < MDL 0.72 1.74 4.70 14.40 23.18
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-9

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for Predators (Fillets) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 206 486 458 5490 ppt < MDL 5.50 13.95 26.80 64.17 158.24 338.96

PCB 207 486 469 1450 ppt 0.80 1.35 3.08 6.04 13.31 30.48 61.95

PCB 208 486 477 3000 ppt 1.03 2.05 3.72 8.77 17.43 52.77 136.02

PCB 209 486 419 3450 ppt < MDL < MDL 7.33 18.06 35.01 78.51 147.97

PCBs (Sum of Congeners)

486 486 704921 ppt 350.81 494.43 999.94 2161.20 8132.51 18173.83 33160.98

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 1 395 81 33 ppt < MDL < MDL < MDL < MDL 0.74 1.19 2.63

PCB 2 395 74 40 ppt < MDL < MDL < MDL < MDL 0.58 0.98 1.56

PCB 3 395 98 23 ppt < MDL < MDL < MDL < MDL 0.63 1.10 1.25

PCB 4 395 263 608 ppt < MDL < MDL < MDL 1.27 4.93 17.00 28.33

PCB 5 395 37 19 ppt < MDL < MDL < MDL < MDL < MDL < MDL 1.04

PCB 6 395 296 601 ppt < MDL < MDL 0.39 1.07 2.91 9.85 13.14

PCB 7 395 129 49 ppt < MDL < MDL < MDL < MDL 0.58 1.68 2.79

PCB 8 395 311 1500 ppt < MDL < MDL < MDL 4.84 11.55 42.57 70.40

PCB 9 395 154 140 ppt < MDL < MDL < MDL 0.03 1.22 3.11 6.11PCB 10 395 59 47 ppt < MDL < MDL < MDL < MDL < MDL 0.88 1.86

PCB 11 395 289 1520 ppt < MDL < MDL < MDL 2.78 9.55 19.96 27.85

PCB 12 + PCB 13 395 78 469 ppt < MDL < MDL < MDL < MDL < MDL 1.98 3.91

PCB 14 395 16 7 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 15 395 312 526 ppt < MDL < MDL < MDL 1.91 5.87 18.45 37.74
E-10

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 16 395 364 2270 ppt < MDL 1.04 2.09 5.12 16.75 43.80 83.25

PCB 17 395 369 2820 ppt < MDL 1.31 2.30 6.61 21.66 81.53 117.01

PCB 18 + PCB 30 395 383 11900 ppt 2.08 3.23 5.79 13.21 48.04 135.81 313.45

PCB 19 395 316 431 ppt < MDL < MDL 0.12 1.08 3.49 16.97 26.46

PCB 20 + PCB 28 395 394 51600 ppt 15.95 19.87 34.67 94.42 262.21 721.87 1668.94PCB 21 + PCB 33 395 373 16200 ppt < MDL 1.07 3.05 7.58 27.36 92.93 176.09PCB 22 395 386 13800 ppt 2.54 3.59 6.63 16.63 51.87 150.97 325.33

PCB 23 395 38 87 ppt < MDL < MDL < MDL < MDL < MDL 0.70 1.49

PCB 24 395 122 167 ppt < MDL < MDL < MDL < MDL 0.91 2.93 4.84

PCB 25 395 340 1170 ppt < MDL < MDL 0.92 2.66 10.79 33.98 109.24

PCB 26 + PCB 29 395 291 7500 ppt < MDL < MDL < MDL 7.49 23.02 76.41 183.76

PCB 27 395 278 976 ppt < MDL < MDL < MDL 1.09 5.40 17.76 28.74

PCB 31 395 388 27300 ppt 7.61 9.63 18.79 44.73 128.98 422.14 1100.16

PCB 32 395 365 5990 ppt < MDL 0.66 1.34 3.18 10.32 41.55 76.23

PCB 34 395 216 248 ppt < MDL < MDL < MDL 0.43 1.61 4.59 11.76

PCB 35 395 9 350 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 36 395 3 47 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 37 395 365 989 ppt < MDL < MDL 1.03 3.83 14.74 57.29 94.66

PCB 38 395 68 80 ppt < MDL < MDL < MDL < MDL < MDL 0.40 1.02

PCB 39 395 176 442 ppt < MDL < MDL < MDL < MDL 0.97 3.55 7.52

PCB 40 + PCB 41 + PCB 71

395 382 45400 ppt 1.26 3.18 5.86 20.59 85.46 343.06 618.81

PCB 42 395 394 28200 ppt 1.52 3.16 7.43 20.01 79.78 248.58 689.02

PCB 43 395 278 4070 ppt < MDL < MDL < MDL 2.58 10.90 30.66 88.44
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-11

Ta

b

le E-2.

P

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um o

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g

eners (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 44 + PCB 47 + PCB 65

395 391 90500 ppt 13.16 20.49 43.77 131.79 503.18 1171.52 3016.97

PCB 45 + PCB 51 395 314 9940 ppt < MDL < MDL < MDL 5.46 21.57 81.96 169.93

PCB 46 395 245 2190 ppt < MDL < MDL < MDL 1.28 5.08 15.24 32.24PCB 48 395 376 22100 ppt < MDL 0.93 2.82 9.96 32.81 91.10 220.45

PCB 49 + PCB 69 395 395 69000 ppt 9.01 17.70 30.99 93.78 365.25 978.47 2411.89PCB 50 + PCB 53 395 239 6760 ppt < MDL < MDL < MDL 2.94 12.11 70.35 143.36PCB 52 395 395 92900 ppt 13.14 18.42 41.98 101.96 402.61 1693.88 3972.16PCB 54 395 93 126 ppt < MDL < MDL < MDL < MDL < MDL 0.67 2.13

PCB 55 395 85 135 ppt < MDL < MDL < MDL < MDL < MDL 3.09 10.39

PCB 56 395 389 26900 ppt 1.71 2.84 6.44 28.06 107.72 410.30 691.27

PCB 57 395 203 364 ppt < MDL < MDL < MDL < MDL 1.76 5.18 19.54PCB 58 395 245 281 ppt < MDL < MDL < MDL 0.90 4.80 16.80 26.36

PCB 59 + PCB 62 + PCB 75

395 370 9330 ppt < MDL 0.83 4.36 12.12 48.35 107.02 301.12

PCB 60 395 394 40200 ppt 5.14 6.51 13.87 35.50 111.30 311.93 639.48

PCB 61 + PCB 70 + PCB 74 + PCB 76

395 395 152000 ppt 22.88 44.23 93.26 253.74 888.24 2836.54 4635.03

PCB 63 395 389 5880 ppt 1.17 1.76 3.92 11.10 44.52 104.51 248.10

PCB 64 395 394 48700 ppt 7.29 12.36 21.95 50.99 183.51 505.63 1453.43

PCB 66 395 395 136000 ppt 24.12 31.66 72.61 196.61 752.96 2157.40 4293.67PCB 67 395 331 789 ppt < MDL < MDL 0.64 2.42 8.39 34.77 67.44

PCB 68 395 380 1090 ppt < MDL 0.53 1.71 4.11 15.30 50.34 80.58

PCB 72 395 369 809 ppt < MDL 0.66 1.64 4.09 16.29 64.65 91.70

PCB 73 395 44 385 ppt < MDL < MDL < MDL < MDL < MDL 0.98 2.37
E-12

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 77 395 279 1060 ppt < MDL < MDL < MDL 7.29 22.97 98.29 166.85

PCB 78 395 5 15 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 79 395 337 571 ppt < MDL < MDL 1.05 3.39 22.36 50.04 83.16

PCB 80 395 26 34 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 81 395 251 260 ppt < MDL < MDL < MDL 0.74 3.13 5.87 13.12

PCB 82 395 383 7950 ppt 0.56 2.83 6.17 20.49 81.53 284.70 490.43

PCB 83 + PCB 99 395 395 35100 ppt 47.62 72.07 173.50 466.40 2075.17 6028.56 7224.01

PCB 84 395 386 10300 ppt 1.54 3.50 7.78 28.68 119.14 405.09 722.83

PCB 85 + PCB 116 + PCB 117

395 395 12500 ppt 15.18 23.20 44.55 108.19 540.02 1133.28 1661.74

PCB 86 + PCB 87 + PCB 97 + PCB 108 + PCB 119 + PCB 125

395 395 39400 ppt 30.14 40.64 86.46 246.65 1326.16 3200.10 4985.40

PCB 88 + PCB 91 395 393 9240 ppt 3.29 5.25 11.18 38.63 212.09 467.11 847.05

PCB 89 395 254 1300 ppt < MDL < MDL < MDL 0.57 2.87 11.66 21.17PCB 90 + PCB 101 + PCB 113

395 395 43700 ppt 51.54 72.76 159.87 473.64 2289.08 6047.76 7853.01

PCB 92 395 395 9080 ppt 9.43 12.65 34.52 96.53 417.99 1263.82 1945.24PCB 93 + PCB 95 + PCB 98 + PCB 100 + PCB 102

395 392 22400 ppt 17.42 26.03 47.06 126.75 564.78 1971.32 3334.05

PCB 94 395 216 502 ppt < MDL < MDL < MDL < MDL 3.23 8.33 13.83

PCB 96 395 143 542 ppt < MDL < MDL < MDL < MDL 1.38 6.05 8.14

PCB 103 395 362 811 ppt < MDL < MDL 0.86 3.04 16.19 54.39 59.06

PCB 104 395 15 34 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 105 395 395 19600 ppt 28.34 33.66 66.53 181.74 897.11 2082.81 2853.02
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-13

Ta

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P

C

Bs—

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um o

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eners (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 106 395 1 11 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 107 + PCB 124 395 392 1210 ppt 2.30 2.89 5.66 17.76 71.20 183.54 258.45

PCB 109 395 394 4460 ppt 8.47 10.48 22.05 59.18 275.82 713.09 871.56PCB 110 + PCB 115 395 395 37200 ppt 49.85 67.46 134.92 385.20 2125.15 4923.92 7759.69

PCB 111 395 302 120 ppt < MDL < MDL 0.41 1.60 5.19 10.68 17.71

PCB 112 395 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 114 395 392 1960 ppt 1.54 2.19 4.91 12.03 57.28 146.87 196.81

PCB 118 395 395 34300 ppt 84.00 109.17 214.61 599.83 2829.83 7664.96 9118.27PCB 120 395 383 829 ppt 0.69 1.22 2.69 7.27 28.82 68.87 93.72

PCB 121 395 240 128 ppt < MDL < MDL < MDL 0.64 1.69 3.57 8.11PCB 122 395 365 538 ppt < MDL 0.30 1.63 4.63 22.57 48.40 61.61

PCB 123 395 390 1410 ppt 1.78 2.66 4.87 13.40 62.42 131.34 168.30

PCB 126 395 158 132 ppt < MDL < MDL < MDL < MDL 12.11 20.64 25.84PCB 127 395 257 147 ppt < MDL < MDL < MDL 1.22 7.96 15.44 22.84

PCB 128 + PCB 166 395 395 10100 ppt 20.64 29.68 56.35 153.78 774.58 1863.88 2402.66

PCB 129 + PCB 138 + PCB 160 + PCB 163

395 395 97200 ppt 169.45 243.36 421.71 1252.21 6629.91 14288.36 19684.69

PCB 130 395 395 5720 ppt 8.59 12.49 24.34 53.51 364.17 693.06 1108.07PCB 131 395 340 525 ppt < MDL < MDL 0.98 3.52 18.73 56.52 83.17

PCB 132 395 395 10100 ppt 8.64 13.96 32.12 83.52 654.34 1392.59 2016.03

PCB 133 395 393 2490 ppt 3.76 4.76 9.97 23.96 122.32 258.02 296.33

PCB 134 + PCB 143 395 384 2230 ppt < MDL 2.34 4.77 15.00 97.30 248.00 400.98

PCB 135 + PCB 151 + PCB 154

395 394 19600 ppt 26.00 31.18 68.63 158.35 1218.02 3024.69 3680.68
E-14

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 136 395 392 3200 ppt 1.36 2.46 5.78 13.37 96.18 314.98 420.22

PCB 137 395 393 4210 ppt 4.67 8.86 16.15 42.74 216.78 611.13 964.42

PCB 139 + PCB 140 395 393 1310 ppt 1.74 2.60 6.01 14.42 83.57 178.60 240.54

PCB 141 395 394 9890 ppt 15.87 22.75 37.91 111.74 795.88 1864.34 2199.33

PCB 142 395 1 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 144 395 383 1760 ppt < MDL 2.49 5.16 15.26 92.22 305.75 333.72

PCB 145 395 48 11 ppt < MDL < MDL < MDL < MDL < MDL 0.59 0.85

PCB 146 395 395 27700 ppt 38.22 51.30 88.81 239.60 1348.14 3122.14 3858.50

PCB 147 + PCB 149 395 395 42000 ppt 47.23 65.26 140.27 391.02 2393.07 4917.49 8596.63

PCB 148 395 328 351 ppt < MDL < MDL 0.65 2.00 9.40 18.10 31.88PCB 150 395 279 200 ppt < MDL < MDL < MDL 0.71 3.38 8.23 13.46

PCB 152 395 161 44 ppt < MDL < MDL < MDL < MDL 0.90 2.67 3.91

PCB 153 + PCB 168 395 395 167000 ppt 181.43 245.54 455.22 1355.59 7417.12 16229.49 19430.50

PCB 155 395 275 2080 ppt < MDL < MDL < MDL 0.40 1.52 4.93 9.42

PCB 156 + PCB 157 395 395 7290 ppt 11.68 18.99 37.47 105.29 543.48 1088.51 1631.64

PCB 158 395 395 6550 ppt 11.48 19.92 34.38 91.22 518.81 1214.94 1454.81PCB 159 395 362 444 ppt < MDL 0.61 2.05 6.15 34.45 73.37 103.30

PCB 161 395 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 162 395 374 395 ppt < MDL 0.97 2.42 6.15 29.53 64.03 86.03

PCB 164 395 395 2660 ppt 5.70 8.59 17.62 44.82 284.79 542.66 810.31PCB 165 395 250 190 ppt < MDL < MDL < MDL 0.71 3.63 7.95 21.01PCB 167 395 395 3540 ppt 7.07 10.84 19.00 59.80 282.11 578.58 755.05

PCB 169 395 278 12 ppt < MDL < MDL < MDL 0.85 1.95 2.70 4.59
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-15

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 170 395 395 27800 ppt 26.84 50.82 86.35 219.15 1262.04 2537.83 4520.81

PCB 171 + PCB 173 395 395 10600 ppt 8.26 13.95 23.35 66.46 390.10 784.06 1418.42

PCB 172 395 395 8530 ppt 7.68 14.10 23.23 71.55 297.28 671.19 1071.29

PCB 174 395 395 12900 ppt 15.01 21.12 44.86 110.35 735.15 1679.90 2346.55

PCB 175 395 393 1400 ppt 1.47 2.26 4.64 11.58 61.26 123.34 208.23PCB 176 395 385 2140 ppt < MDL 1.41 3.36 9.66 59.27 191.60 249.36

PCB 177 395 395 17800 ppt 12.97 21.62 43.35 107.91 618.33 1831.74 2448.54

PCB 178 395 395 7430 ppt 9.40 15.44 26.78 74.13 428.19 824.26 1358.00

PCB 179 395 391 5500 ppt 4.69 7.06 16.80 40.49 252.40 674.36 850.58

PCB 180 + PCB 193 395 395 105000 ppt 76.16 161.15 253.40 660.50 3757.41 7914.49 12915.10

PCB 181 395 350 219 ppt < MDL 0.15 1.01 2.88 12.65 30.26 36.38

PCB 182 395 334 445 ppt < MDL < MDL 1.32 4.13 16.03 38.27 68.35

PCB 183 + PCB 185 395 391 28800 ppt 19.78 36.62 68.04 168.01 1109.79 2480.11 3676.59PCB 184 395 310 2960 ppt < MDL < MDL 0.60 1.23 3.48 7.60 11.57

PCB 186 395 4 3 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 187 395 395 55600 ppt 59.60 108.19 186.28 558.26 3031.01 6548.66 10617.91PCB 188 395 135 194 ppt < MDL < MDL < MDL < MDL 6.12 13.51 26.17PCB 189 395 390 1160 ppt 1.24 2.59 4.68 11.05 50.01 113.50 171.79

PCB 190 395 395 7720 ppt 7.08 12.23 20.31 52.64 291.78 580.17 982.03

PCB 191 395 391 1600 ppt 1.21 2.31 3.91 8.78 51.99 109.70 175.62

PCB 192 395 45 15 ppt < MDL < MDL < MDL < MDL < MDL 0.13 0.75

PCB 194 395 395 17500 ppt 16.81 30.53 57.08 155.75 666.36 1630.24 2552.66

PCB 195 395 377 6510 ppt < MDL 9.70 18.07 50.89 238.13 520.39 954.87
E-16

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-2.

P

C

Bs—

S

um o

f Co

n

g

eners (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 196 395 392 10100 ppt 9.03 15.75 30.71 90.41 338.94 825.66 1275.23

PCB 197 + PCB 200 395 389 1680 ppt 1.86 3.19 7.51 17.81 82.38 170.72 304.37PCB 198 + PCB 199 395 392 19300 ppt 22.77 46.04 94.48 306.71 939.61 2429.55 4326.00PCB 201 395 354 1800 ppt < MDL < MDL 9.85 24.23 104.29 185.48 342.83

PCB 202 395 392 2840 ppt 5.10 9.99 21.97 62.00 246.60 431.36 778.99PCB 203 395 391 14400 ppt 11.48 26.58 55.71 173.29 635.83 1378.73 2349.98

PCB 204 395 169 45 ppt < MDL < MDL < MDL < MDL 1.56 2.98 3.79

PCB 205 395 386 856 ppt 0.83 1.65 3.56 9.69 32.66 87.98 136.70PCB 206 395 393 8660 ppt 11.46 27.96 75.30 150.55 468.49 785.51 1289.77PCB 207 395 395 1920 ppt 2.86 4.87 12.47 30.35 86.84 122.39 214.88

PCB 208 395 395 6000 ppt 6.17 12.28 32.79 74.89 194.61 374.16 637.41

PCB 209 395 388 29200 ppt 9.11 14.55 45.05 106.51 263.89 519.56 730.76

PCBs (Sum of Congeners)

395 395 1266249 ppt 1581.27 2314.73 5146.35 13902.31 70870.03 130787.45 198323.80
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-17

Ta

b

le E-3.

P

C

Bs—

S

um o

f A

r

ocl

o

rs

Tissue Concentration Estimates for Predators (Fillets)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 1016 486 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1221 486 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1232 486 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1242 486 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1248 486 2 33 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1254 486 8 182 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1260 486 109 421 ppt < MDL < MDL < MDL < MDL < MDL 14.82 22.10

PCBs (Sum of Aroclors) 486 111 421 ppb < MDL < MDL < MDL < MDL < MDL 14.88 22.15

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

PCB 1016 395 1 16 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1221 395 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1232 395 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1242 395 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1248 395 12 1562 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1254 395 10 446 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

PCB 1260 395 208 1004 ppt < MDL < MDL < MDL < MDL 39.81 84.71 118.06

PCBs (Sum of Aroclors) 395 214 1562 ppb < MDL < MDL < MDL < MDL 39.84 85.12 122.98
E-18

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-4.

Dioxi

ns and F

urans

Tissue Concentration Estimates for Predators (Fillets)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

2,3,7,8-TCDD 486 188 2 ppt < MDL < MDL < MDL < MDL 0.03 0.08 0.101,2,3,7,8-PeCDD 486 83 3 ppt < MDL < MDL < MDL < MDL < MDL < MDL 0.07

1,2,3,4,7,8-HxCDD 486 15 0.3 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

1,2,3,6,7,8-HxCDD 486 136 5 ppt < MDL < MDL < MDL < MDL < MDL 0.06 0.09

1,2,3,7,8,9-HxCDD 486 26 0.4 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

1,2,3,4,6,7,8-HpCDD 486 74 11 ppt < MDL < MDL < MDL < MDL < MDL 0.04 0.09

OCDD 486 18 10 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

2,3,7,8-TCDF 486 347 7 ppt < MDL < MDL < MDL 0.002 0.06 0.10 0.181,2,3,7,8-PeCDF 486 33 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

2,3,4,7,8-PeCDF 486 66 5 ppt < MDL < MDL < MDL < MDL < MDL < MDL 0.07

1,2,3,4,7,8-HxCDF 486 28 0.2 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

1,2,3,6,7,8-HxCDF 486 12 0.3 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

1,2,3,7,8,9-HxCDF 486 3 0.07 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

2,3,4,6,7,8-HxCDF 486 8 0.4 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

1,2,3,4,6,7,8-HpCDF 486 12 2 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

1,2,3,4,7,8,9-HpCDF 486 0 Not Applicable ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

OCDF 486 10 1 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Dioxins and Furans TEQ

486 395 8 ppt < MDL < MDL < MDL 0.006 0.05 0.11 0.32

12 Coplanar PCBs TEQ 486 485 38.7 ppt 0.004 0.006 0.01 0.03 0.09 0.23 0.92Total TEQ 486 485 46.2 ppt 0.004 0.006 0.01 0.04 0.14 0.51 1.24
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-19

Ta

b

le E-4.

Dioxi

ns and F

urans (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

2,3,7,8-TCDD 395 319 17 ppt < MDL < MDL 0.04 0.09 0.24 0.53 0.781,2,3,7,8-PeCDD 395 299 10 ppt < MDL < MDL < MDL 0.10 0.30 0.56 0.66

1,2,3,4,7,8-HxCDD 395 229 13 ppt < MDL < MDL < MDL 0.06 0.20 0.39 0.491,2,3,6,7,8-HxCDD 395 340 24 ppt < MDL 0.04 0.09 0.16 0.62 1.11 1.431,2,3,7,8,9-HxCDD 395 222 19 ppt < MDL < MDL < MDL 0.05 0.11 0.27 0.44

1,2,3,4,6,7,8-HpCDD 395 260 142 ppt < MDL < MDL < MDL 0.28 1.19 3.22 3.88

OCDD 395 186 480 ppt < MDL < MDL < MDL 0.30 6.42 17.21 28.52

2,3,7,8-TCDF 395 374 12 ppt < MDL 0.02 0.09 0.17 0.44 1.28 1.99

1,2,3,7,8-PeCDF 395 219 8 ppt < MDL < MDL < MDL 0.04 0.09 0.14 0.19

2,3,4,7,8-PeCDF 395 301 3 ppt < MDL < MDL 0.06 0.09 0.22 0.37 0.46

1,2,3,4,7,8-HxCDF 395 170 20 ppt < MDL < MDL < MDL < MDL 0.05 0.09 0.101,2,3,6,7,8-HxCDF 395 148 5 ppt < MDL < MDL < MDL < MDL 0.06 0.09 0.101,2,3,7,8,9-HxCDF 395 10 0.3 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

2,3,4,6,7,8-HxCDF 395 89 1 ppt < MDL < MDL < MDL < MDL < MDL 0.08 0.10

1,2,3,4,6,7,8-HpCDF 395 159 7 ppt < MDL < MDL < MDL < MDL 0.09 0.19 0.341,2,3,4,7,8,9-HpCDF 395 4 3 ppt < MDL < MDL < MDL < MDL < MDL < MDL < MDL

OCDF 395 35 9 ppt < MDL < MDL < MDL < MDL < MDL 0.18 0.33

Dioxins and Furans TEQ

395 393 24 ppt 0.02 0.06 0.16 0.41 1.07 1.77 2.01

12 Coplanar PCBs TEQ 395 395 20.0 ppt 0.02 0.03 0.06 0.15 1.92 4.01 4.65

Total TEQ 395 395 27.1 ppt 0.07 0.11 0.29 0.68 2.89 5.30 5.83
E-20

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-5. Or

g

an

o

c

h

l

o

rine P

est icides

Tissue Concentration Estimates for Predators (Fillets)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Aldrin 486 6 8 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Dicofol 486 15 1235 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Dieldrin 486 24 18 ppb < MDL < MDL < MDL < MDL < MDL < MDL 1.19

Endosulfan Sulfate 486 1 11 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Endrin 486 3 12 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Ethalfluralin 486 20 12 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Heptachlor 486 17 8 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Heptachlor epoxide 486 6 3 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Hexachlorocyclohexane (BHC), alpha486 5 8 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDLHexachlorocyclohexane (BHC), beta486 39 9 ppb < MDL < MDL < MDL < MDL < MDL < MDL 1.78Hexachlorocyclohexane (BHC), delta486 7 4 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Isodrin 486 16 5 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Kepone (Chlordecone) 486 60 129 ppb < MDL < MDL < MDL < MDL < MDL 16.29 24.92

Lindane (Hexachlorocyclohexane, gamma-BHC)

486 28 3 ppb < MDL < MDL < MDL < MDL < MDL < MDL 0.99

Methoxychlor 486 9 370 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Mirex 486 10 9 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Octachlorostyrene 486 6 19 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Pendimethalin 486 1 13 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Pentachloroanisole 486 57 4 ppb < MDL < MDL < MDL < MDL < MDL 1.45 2.16

Pentachloronitrobenzene 486 29 4 ppb < MDL < MDL < MDL < MDL < MDL < MDL 1.07

Permethrin, cis- 486 5 325 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-21

Ta

b

le E-5. Or

g

an

o

c

h

l

o

rine P

est icides (continued)

Tissue Concentration Estimates for Predators (Fillets)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Permethrin, trans- 486 4 131 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Toxaphene 486 0 Not Applicable ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Trifluralin 486 36 11 ppb < MDL < MDL < MDL < MDL < MDL < MDL 3.16

Tissue Concentration Estimates for 

B

ottom Dweller (Whole 

B

odies)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Aldrin 395 9 22 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Dicofol 395 8 269 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Dieldrin 395 73 392 ppb < MDL < MDL < MDL < MDL < MDL 3.44 24.61

Endosulfan Sulfate 395 19 22 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Endrin 395 14 20 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Ethalfluralin 395 90 16 ppb < MDL < MDL < MDL < MDL < MDL 3.38 4.93

Heptachlor 395 24 17 ppb < MDL < MDL < MDL < MDL < MDL < MDL 2.43

Heptachlor epoxide 395 25 14 ppb < MDL < MDL < MDL < MDL < MDL < MDL 0.68

Hexachlorocyclohexane (BHC), alpha395 8 6 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDLHexachlorocyclohexane (BHC), beta395 38 39 ppb < MDL < MDL < MDL < MDL < MDL < MDL 2.1Hexachlorocyclohexane (BHC), delta395 21 15 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Isodrin 395 19 12 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Kepone (Chlordecone) 395 92 2008 ppb < MDL < MDL < MDL < MDL 13.91 69.89 84.94

Lindane (Hexachlorocyclohexane, gamma-BHC)

395 31 9 ppb < MDL < MDL < MDL < MDL < MDL 0.73 1.54
E-22

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-5. Or

g

an

o

c

h

l

o

rine P

est icides (continued)

Tissue Concentration Estimates for 

B

ottom Dweller (Whole 

B

odies) (continued)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Methoxychlor 395 23 107 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Mirex 395 19 29 ppb < MDL < MDL < MDL < MDL < MDL < MDL 1.87

Octachlorostyrene 395 8 3 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Pendimethalin 395 19 33 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Pentachloroanisole 395 92 9 ppb < MDL < MDL < MDL < MDL 1.37 4.02 4.63

Pentachloronitrobenzene 395 50 5 ppb < MDL < MDL < MDL < MDL < MDL 1.34 1.59

Permethrin, cis- 395 27 441 ppb < MDL < MDL < MDL < MDL < MDL < MDL 40.39

Permethrin, trans- 395 12 264 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Toxaphene 395 1 91 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Trifluralin 395 144 96 ppb < MDL < MDL < MDL < MDL 3.76 7.26 13.88
The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

E-23

Ta

b

le E-6.

S

ummed Or

g

an

o

c

h

l

o

rine P

est icides

Tissue Concentration Estimates for Predators (Fillets)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Total Chlordane

Chlordane, alpha- 486 33 20 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Chlordane, gamma- 486 13 6 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Nonachlor, cis- 486 23 10 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Nonachlor, trans- 486 56 70 ppb < MDL < MDL < MDL < MDL < MDL 1.79 4.04

Oxychlordane 486 23 10 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Total Chlordane 486 96 100 ppb < MDL < MDL < MDL < MDL < MDL 3.62 8.27

Total DDT

2,4'-DDD 352 5 3 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

2,4'-DDE 352 34 9 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

2,4'-DDT 352 18 10 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

4,4'-DDD 486 46 41 ppb < MDL < MDL < MDL < MDL < MDL < MDL 3.8

4,4'-DDE 486 374 1394 ppb < MDL < MDL < MDL 1.38 4 16.87 30.03

4,4'-DDT 486 43 50 ppb < MDL < MDL < MDL < MDL < MDL < MDL 2.23

Total DDT 486 378 1481 ppb < MDL < MDL < MDL 1.47 6.95 19.68 30.57

Total Endosulfan

Endosulfan I 486 18 59 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Endosulfan II 486 0 Not Applicable ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Total Endosulfan 486 18 59 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL
E-24

The National Study of Chemical Residues in Lake Fish Tissue

Appendix E: Percentile Tables for Detected Target Chemicals

Ta

b

le E-6.

S

ummed Or

g

an

o

c

h

l

o

rine P

est icides (continued)

Tissue Concentration Estimates for 

B

ottom Dwellers (Whole 

B

odies)

Chemical

Number 

of 

Samples

Number 

of 

Detects

Maximum 

Concentration Units

5th

Percentile

10th

Percentile

25th

Percentile

50th

Percentile

75th

Percentile

90th

Percentile

95th

Percentile

Total Chlordane

Chlordane, alpha- 395 122 178 ppb < MDL < MDL < MDL < MDL 3.75 6.17 10.44

Chlordane, gamma- 395 48 80 ppb < MDL < MDL < MDL < MDL < MDL 0.63 1.15

Nonachlor, cis- 395 68 68 ppb < MDL < MDL < MDL < MDL < MDL 7.14 9.71

Nonachlor, trans- 395 159 87 ppb < MDL < MDL < MDL < MDL 4.08 5.77 12.05

Oxychlordane 395 45 12 ppb < MDL < MDL < MDL < MDL < MDL 3.6 6.25

Total Chlordane 395 197 378 ppb < MDL < MDL < MDL 1.65 9.31 25.96 30.93

Total DDT

2,4'-DDD 274 27 13 ppb < MDL < MDL < MDL < MDL < MDL < MDL 0.82

2,4'-DDE 274 112 41 ppb < MDL < MDL < MDL < MDL 1.32 3.01 3.7

2,4'-DDT 274 28 20 ppb < MDL < MDL < MDL < MDL < MDL < MDL 0.84

4,4'-DDD 395 147 159 ppb < MDL < MDL < MDL < MDL 5.17 11.68 23.89

4,4'-DDE 395 387 1743 ppb 1.02 1.43 3.77 9.66 32.12 99.89 198.67

4,4'-DDT 395 60 42 ppb < MDL < MDL < MDL < MDL < MDL 1.41 3.02

Total DDT 395 388 1761 ppb 1.08 1.82 4.23 12.68 35.35 153.92 218.63

Total Endosulfan

Endosulfan I 395 23 38.6 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Endosulfan II 395 0 Not Applicable ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL

Total Endosulfan 395 23 38.6 ppb < MDL < MDL < MDL < MDL < MDL < MDL < MDL
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F

Occurrence of Target Chemicals

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-1

Metal Results for Predators

Chemical

MDL

ng/g (ppb)

ML

ng/g (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Mercury 0.521 2 0 0 486 486

Chemical

MDL

μg/g (ppm)

ML

μg/g (ppm)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Arsenate 0.03 0.1 484 2 0 486

Arsenite 0.02 0.1 486 0 0 486

Total Inorganic Arsenic 0.03 0.1 484 2 0 486

Dimethylarsonic Acid 0.04 0.1 482 3 1 486

Monomethylarsonic Acid 0.01 0.05 480 6 0 486

Metal Results for Bottom Dwellers

Chemical

MDL

μg/g (ppb)

ML

μg/g (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Mercury 0.521 2 0 0 395 395

Chemical

MDL

μg/g (ppm)

ML

μg/g (ppm)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Arsenate 0.03 0.1 391 3 1 395

Arsenite 0.02 0.1 334 53 8 395

Total Inorganic Arsenic 0.03 0.1 359 30 6 395

Dimethylarsonic Acid 0.04 0.1 386 9 0 395

Monomethylarsonic Acid 0.01 0.05 395 0 0 395

Polychlorinated Biphenyl (PCB) Results for Predators

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-1 0.8 2.0 449 26 7 482*

PCB-2 0.8 2.0 474 5 3 482*

PCB-3 0.6 2.0 353 113 19 485*

PCB-4 0.5 2.0 272 148 66 486

PCB-5 0.7 2.0 482 2 2 486

PCB-6 0.3 1.0 313 124 49 486

PCB-7 0.4 1.0 394 59 33 486

PCB-8 1.3 5.0 311 129 46 486

PCB-9 0.5 2.0 448 30 8 486

PCB-10 0.7 2.0 471 10 5 486

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
F-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

Polychlorinated Biphenyl (PCB) Results for Predators (continued)

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-11 1.0 2.0 221 156 109 486

PCB-12+PCB-13 1.0 2.0 472 9 5 486

PCB-14 0.5 2.0 485 1 0 486

PCB-15 0.4 1.0 227 135 124 486

PCB-16 1.0 2.0 198 115 173 486

PCB-17 1.0 2.0 146 120 220 486

PCB-18+PCB-30 1.8 5.0 115 185 186 486

PCB-19 0.1 0.5 198 130 158 486

PCB-20+PCB-28 4.2 10.0 57 115 314 486

PCB-21+PCB-33 1.0 2.0 84 115 287 486

PCB-22 0.2 0.5 46 8 432 486

PCB-23 0.6 2.0 478 7 1 486

PCB-24 0.8 2.0 455 17 14 486

PCB-25 0.6 2.0 223 146 117 486

PCB-26+PCB-29 3.5 10.0 339 83 64 486

PCB-27 0.7 2.0 345 78 63 486

PCB-31 0.5 2.0 51 17 418 486

PCB-32 0.6 2.0 199 176 111 486

PCB-34 0.5 2.0 413 49 24 486

PCB-35 0.4 1.0 485 1 0 486

PCB-36 0.5 2.0 484 2 0 486

PCB-37 0.2 0.5 47 69 370 486

PCB-38 0.4 1.0 464 13 9 486

PCB-39 0.5 2.0 434 35 17 486

PCB-40+PCB-41+PCB-71 1.6 5.0 78 141 267 486

PCB-42 0.7 2.0 30 98 358 486

PCB-43 1.4 5.0 334 88 64 486

PCB-44+PCB-47+PCB-65 4.3 10.0 33 86 367 486

PCB-45+PCB-51 2.2 5.0 295 81 110 486

PCB-46 1.2 5.0 392 64 30 486

PCB-48 0.8 2.0 96 113 277 486

PCB-49+PCB-69 1.4 5.0 7 69 410 486

PCB-50+PCB-53 3.2 10.0 362 75 49 486

PCB-52 4.3 10.0 16 66 404 486

PCB-54 0.3 1.0 452 16 18 486

PCB-55 0.5 2.0 423 38 25 486

PCB-56 0.5 2.0 18 67 401 486

PCB-57 0.6 2.0 372 66 48 486
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-3

Polychlorinated Biphenyl (PCB) Results for Predators (continued)

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-58 0.5 2.0 354 77 55 486

PCB-59+PCB-62+PCB-75 2.0 5.0 199 127 160 486

PCB-60 0.4 1.0 6 19 461 486

PCB-61+PCB-70+PCB-74+PCB-76 2.3 10.0 0 25 461 486

PCB-63 0.7 2.0 80 141 265 486

PCB-64 0.6 2.0 1 31 454 486

PCB-66 5.2 20.0 25 107 354 486

PCB-67 0.6 2.0 190 153 143 486

PCB-68 0.4 1.0 107 135 244 486

PCB-72 0.5 2.0 160 179 147 486

PCB-73 0.7 2.0 466 8 12 486

PCB-77 4.9 20.0 304 128 54 486

PCB-78 0.7 2.0 485 1 0 486

PCB-79 0.8 2.0 201 105 180 486

PCB-80 0.8 2.0 484 1 1 486

PCB-81 0.5 2.0 381 80 25 486

PCB-82 0.6 2.0 29 61 396 486

PCB-83+PCB-99 1.0 2.0 1 0 485 486

PCB-84 0.9 2.0 36 48 402 486

PCB-85+PCB-116+PCB-117 1.0 2.0 0 5 481 486

PCB-86+PCB-87+PCB-97+ 

PCB-108+PCB-119+PCB-125

4.5 20.0 9 65 412 486

PCB-88+PCB-91 0.8 2.0 16 43 427 486

PCB-89 0.6 2.0 364 77 45 486

PCB-90+PCB-101+PCB-113 3.7 10.0 1 9 476 486

PCB-92 0.1 0.5 4 0 482 486

PCB-93+PCB-95+PCB-98+ 

PCB-100+PCB-102

2.1 5.0 15 21 450 486

PCB-94 0.6 2.0 409 40 37 486

PCB-96 1.0 2.0 438 22 26 486

PCB-103 0.4 1.0 159 90 237 486

PCB-104 3.6 10.0 485 1 0 486

PCB-105 5.3 20.0 15 82 389 486

PCB-106 0.4 1.0 486 0 0 486

PCB-107+PCB-124 1.0 2.0 36 55 395 486

PCB-109 0.5 2.0 7 20 459 486

PCB-110+PCB-115 0.5 2.0 0 0 486 486

PCB-111 0.4 1.0 271 105 110 486

PCB-112 0.6 2.0 485 0 1 486

PCB-114 0.4 1.0 27 47 412 486
F-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

Polychlorinated Biphenyl (PCB) Results for Predators (continued)

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-118 4.9 20.0 2 21 463 486

PCB-120 0.5 2.0 78 166 242 486

PCB-121 0.6 2.0 381 74 31 486

PCB-122 0.3 1.0 204 70 212 486

PCB-123 1.1 2.0 85 83 318 486

PCB-126 5.1 20.0 435 47 4 486

PCB-127 0.5 2.0 312 97 77 486

PCB-128+PCB-166 3.7 10.0 8 39 439 486

PCB-129+PCB-138+ 

PCB-160+PCB-163

5.4 20.0 0 5 481 486

PCB-130 0.4 1.0 4 5 477 486

PCB-131 0.6 2.0 170 129 187 486

PCB-132 0.8 2.0 0 19 467 486

PCB-133 0.5 2.0 9 59 418 486

PCB-134+PCB-143 0.8 2.0 51 78 357 486

PCB-135+PCB-151+PCB-154 4.0 10.0 13 31 442 486

PCB-136 0.6 2.0 50 73 363 486

PCB-137 0.4 1.0 5 7 474 486

PCB-139+PCB-140 0.8 2.0 40 68 378 486

PCB-141 0.7 2.0 0 4 482 486

PCB-142 0.5 2.0 485 0 1 486

PCB-144 0.7 2.0 41 51 394 486

PCB-145 0.5 2.0 479 7 0 486

PCB-146 0.4 1.0 0 0 486 486

PCB-147+PCB-149 0.6 2.0 2 0 484 486

PCB-148 0.6 2.0 232 126 128 486

PCB-150 0.4 1.0 311 84 91 486

PCB-152 0.4 1.0 448 22 16 486

PCB-153+PCB-168 4.1 10.0 0 2 484 486

PCB-155 0.3 1.0 287 116 83 486

PCB-156+PCB-157 0.5 2.0 2 11 473 486

PCB-158 0.4 1.0 1 2 483 486

PCB-159 0.4 1.0 87 77 322 486

PCB-161 0.5 2.0 486 0 0 486

PCB-162 0.4 1.0 75 64 347 486

PCB-164 0.3 1.0 5 7 474 486

PCB-165 0.4 1.0 315 77 94 486

PCB-167 0.2 1.0 3 6 477 486

PCB-169 0.3 1.0 383 65 38 486
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-5

Polychlorinated Biphenyl (PCB) Results for Predators (continued)

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-170 5.0 20.0 12 62 412 486

PCB-171+PCB-173 0.8 2.0 5 15 466 486

PCB-172 0.5 2.0 5 18 463 486

PCB-174 0.6 2.0 2 9 475 486

PCB-175 0.6 2.0 50 91 345 486

PCB-176 0.5 2.0 73 119 294 486

PCB-177 0.3 1.0 1 1 484 486

PCB-178 0.8 2.0 4 13 469 486

PCB-179 0.4 1.0 19 22 445 486

PCB-180+PCB-193 4.5 10.0 2 3 481 486

PCB-181 0.5 2.0 177 153 156 486

PCB-182 0.8 2.0 159 117 210 486

PCB-183+PCB-185 1.1 5.0 7 7 472 486

PCB-184 0.6 2.0 272 122 92 486

PCB-186 0.7 2.0 485 0 1 486

PCB-187 4.3 10.0 2 8 476 486

PCB-188 4.6 10.0 437 33 16 486

PCB-189 0.4 1.0 38 47 401 486

PCB-190 0.3 1.0 4 3 479 486

PCB-191 0.5 2.0 49 117 320 486

PCB-192 0.3 1.0 469 12 5 486

PCB-194 1.1 5.0 3 18 465 486

PCB-195 4.9 20.0 95 193 198 486

PCB-196 0.8 2.0 6 12 468 486

PCB-197+PCB-200 0.8 2.0 50 77 359 486

PCB-198+PCB-199 0.8 2.0 0 2 484 486

PCB-201 4.9 20.0 189 180 117 486

PCB-202 0.5 2.0 14 18 454 486

PCB-203 0.8 2.0 4 8 474 486

PCB-204 0.9 2.0 419 40 27 486

PCB-205 0.5 2.0 61 145 280 486

PCB-206 4.5 10.0 27 54 405 486

PCB-207 0.5 2.0 16 54 416 486

PCB-208 0.5 2.0 8 25 453 486

PCB-209 5.0 20.0 66 197 223 486

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
F-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

Polychlorinated Biphenyl (PCB) Results for Bottom Dwellers

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-1 0.8 2.0 313 58 23 394*

PCB-2 0.8 2.0 320 55 19 394*

PCB-3 0.6 2.0 296 87 11 394*

PCB-4 0.5 2.0 132 84 179 395

PCB-5 0.7 2.0 358 27 10 395

PCB-6 0.3 1.0 99 104 192 395

PCB-7 0.4 1.0 266 71 58 395

PCB-8 1.3 5.0 84 132 179 395

PCB-9 0.5 2.0 241 115 39 395

PCB-10 0.7 2.0 336 33 26 395

PCB-11 1.0 2.0 106 52 237 395

PCB-12+PCB-13 1.0 2.0 317 38 40 395

PCB-14 0.5 2.0 379 14 2 395

PCB-15 0.4 1.0 83 44 268 395

PCB-16 1.0 2.0 31 45 319 395

PCB-17 1.0 2.0 26 48 321 395

PCB-18+PCB-30 1.8 5.0 12 56 327 395

PCB-19 0.1 0.5 79 31 285 395

PCB-20+PCB-28 4.2 10.0 1 2 392 395

PCB-21+PCB-33 1.0 2.0 22 25 348 395

PCB-22 0.2 0.5 9 0 386 395

PCB-23 0.6 2.0 357 30 8 395

PCB-24 0.8 2.0 273 61 61 395

PCB-25 0.6 2.0 55 94 246 395

PCB-26+PCB-29 3.5 10.0 104 119 172 395

PCB-27 0.7 2.0 117 106 172 395

PCB-31 0.5 2.0 7 0 388 395

PCB-32 0.6 2.0 30 101 264 395

PCB-34 0.5 2.0 179 126 90 395

PCB-35 0.4 1.0 386 5 4 395

PCB-36 0.5 2.0 392 2 1 395

PCB-37 0.2 0.5 30 7 358 395

PCB-38 0.4 1.0 327 32 36 395

PCB-39 0.5 2.0 219 103 73 395

PCB-40+PCB-41+PCB-71 1.6 5.0 13 37 345 395

PCB-42 0.7 2.0 1 16 378 395

PCB-43 1.4 5.0 117 116 162 395

PCB-44+PCB-47+PCB-65 4.3 10.0 4 4 387 395

PCB-45+PCB-51 2.2 5.0 81 82 232 395

PCB-46 1.2 5.0 150 132 113 395

PCB-48 0.8 2.0 19 27 349 395
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-7

Polychlorinated Biphenyl (PCB) Results for Bottom Dwellers (continued)

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-49+PCB-69 1.4 5.0 0 2 393 395

PCB-50+PCB-53 3.2 10.0 156 106 133 395

PCB-52 4.3 10.0 0 11 384 395

PCB-54 0.3 1.0 302 46 47 395

PCB-55 0.5 2.0 310 30 55 395

PCB-56 0.5 2.0 6 12 377 395

PCB-57 0.6 2.0 192 86 117 395

PCB-58 0.5 2.0 150 88 157 395

PCB-59+PCB-62+PCB-75 2.0 5.0 25 73 297 395

PCB-60 0.4 1.0 1 0 394 395

PCB-61+PCB-70+PCB-74+PCB-76 2.3 10.0 0 1 394 395

PCB-63 0.7 2.0 6 25 364 395

PCB-64 0.6 2.0 1 0 394 395

PCB-66 5.2 20.0 0 8 387 395

PCB-67 0.6 2.0 64 84 247 395

PCB-68 0.4 1.0 15 28 352 395

PCB-72 0.5 2.0 26 87 282 395

PCB-73 0.7 2.0 351 16 28 395

PCB-77 4.9 20.0 116 141 138 395

PCB-78 0.7 2.0 390 1 4 395

PCB-79 0.8 2.0 58 58 279 395

PCB-80 0.8 2.0 369 19 7 395

PCB-81 0.5 2.0 144 117 134 395

PCB-82 0.6 2.0 12 9 374 395

PCB-83+PCB-99 1.0 2.0 0 0 395 395

PCB-84 0.9 2.0 9 4 382 395

PCB-85+PCB-116+PCB-117 1.0 2.0 0 0 395 395

PCB-86+PCB-87+PCB-97+ 

PCB-108+PCB-119+PCB-125

4.5 20.0 0 5 390 395

PCB-88+PCB-91 0.8 2.0 2 4 389 395

PCB-89 0.6 2.0 141 105 149 395

PCB-90+PCB-101+PCB-113 3.7 10.0 0 0 395 395

PCB-92 0.1 0.5 0 0 395 395

PCB-93+PCB-95+PCB-98+ 

PCB-100+PCB-102

2.1 5.0 3 0 392 395

PCB-94 0.6 2.0 179 92 124 395

PCB-96 1.0 2.0 252 48 95 395

PCB-103 0.4 1.0 33 46 316 395

PCB-104 3.6 10.0 380 11 4 395

PCB-105 5.3 20.0 0 9 386 395

PCB-106 0.4 1.0 394 0 1 395

PCB-107+PCB-124 1.0 2.0 3 8 384 395
F-8

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

Polychlorinated Biphenyl (PCB) Results for Bottom Dwellers (continued)

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-109 0.5 2.0 1 0 394 395

PCB-110+PCB-115 0.5 2.0 0 0 395 395

PCB-111 0.4 1.0 93 60 242 395

PCB-112 0.6 2.0 395 0 0 395

PCB-114 0.4 1.0 3 4 388 395

PCB-118 4.9 20.0 0 1 394 395

PCB-120 0.5 2.0 12 53 330 395

PCB-121 0.6 2.0 155 147 93 395

PCB-122 0.3 1.0 30 22 343 395

PCB-123 1.1 2.0 5 17 373 395

PCB-126 5.1 20.0 237 107 51 395

PCB-127 0.5 2.0 138 75 182 395

PCB-128+PCB-166 3.7 10.0 0 2 393 395

PCB-129+PCB-138+PCB-160+ 

PCB-163

5.4 20.0 0 0 395 395

PCB-130 0.4 1.0 0 0 395 395

PCB-131 0.6 2.0 55 50 290 395

PCB-132 0.8 2.0 0 1 394 395

PCB-133 0.5 2.0 2 3 390 395

PCB-134+PCB-143 0.8 2.0 11 11 373 395

PCB-135+PCB-151+PCB-154 4.0 10.0 1 0 394 395

PCB-136 0.6 2.0 3 12 380 395

PCB-137 0.4 1.0 2 0 393 395

PCB-139+PCB-140 0.8 2.0 2 15 378 395

PCB-141 0.7 2.0 1 0 394 395

PCB-142 0.5 2.0 394 1 0 395

PCB-144 0.7 2.0 12 5 378 395

PCB-145 0.5 2.0 347 35 13 395

PCB-146 0.4 1.0 0 0 395 395

PCB-147+PCB-149 0.6 2.0 0 0 395 395

PCB-148 0.6 2.0 67 93 235 395

PCB-150 0.4 1.0 116 77 202 395

PCB-152 0.4 1.0 234 61 100 395

PCB-153+PCB-168 4.1 10.0 0 0 395 395

PCB-155 0.3 1.0 120 116 159 395

PCB-156+PCB-157 0.5 2.0 0 0 395 395

PCB-158 0.4 1.0 0 0 395 395

PCB-159 0.4 1.0 33 13 349 395

PCB-161 0.5 2.0 395 0 0 395

PCB-162 0.4 1.0 21 15 359 395

PCB-164 0.3 1.0 0 0 395 395
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-9

Polychlorinated Biphenyl (PCB) Results for Bottom Dwellers (continued)

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

PCB-165 0.4 1.0 145 46 204 395

PCB-167 0.2 1.0 0 0 395 395

PCB-169 0.3 1.0 117 63 215 395

PCB-170 5.0 20.0 0 10 385 395

PCB-171+PCB-173 0.8 2.0 0 0 395 395

PCB-172 0.5 2.0 0 0 395 395

PCB-174 0.6 2.0 0 0 395 395

PCB-175 0.6 2.0 2 26 367 395

PCB-176 0.5 2.0 10 25 360 395

PCB-177 0.3 1.0 0 0 395 395

PCB-178 0.8 2.0 0 0 395 395

PCB-179 0.4 1.0 4 0 391 395

PCB-180+PCB-193 4.5 10.0 0 0 395 395

PCB-181 0.5 2.0 45 80 270 395

PCB-182 0.8 2.0 61 49 285 395

PCB-183+PCB-185 1.1 5.0 4 0 391 395

PCB-184 0.6 2.0 85 137 173 395

PCB-186 0.7 2.0 391 2 2 395

PCB-187 4.3 10.0 0 0 395 395

PCB-188 4.6 10.0 260 66 69 395

PCB-189 0.4 1.0 5 9 381 395

PCB-190 0.3 1.0 0 0 395 395

PCB-191 0.5 2.0 4 30 361 395

PCB-192 0.3 1.0 350 28 17 395

PCB-194 1.1 5.0 0 0 395 395

PCB-195 4.9 20.0 18 73 304 395

PCB-196 0.8 2.0 3 0 392 395

PCB-197+PCB-200 0.8 2.0 6 16 373 395

PCB-198+PCB-199 0.8 2.0 3 0 392 395

PCB-201 4.9 20.0 41 111 243 395

PCB-202 0.5 2.0 3 1 391 395

PCB-203 0.8 2.0 4 0 391 395

PCB-204 0.9 2.0 226 82 87 395

PCB-205 0.5 2.0 9 35 351 395

PCB-206 4.5 10.0 2 9 384 395

PCB-207 0.5 2.0 0 7 388 395

PCB-208 0.5 2.0 0 1 394 395

PCB-209 5.0 20.0 7 49 339 395

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
F-10

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

PCB Aroclor Results for Predators

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Aroclor-1016 0.68 20 486 0 0 486

Aroclor-1221 0.76 20 486 0 0 486

Aroclor-1232 0.76 20 486 0 0 486

Aroclor-1242 0.76 20 486 0 0 486

Aroclor-1248 0.76 20 484 1 1 486

Aroclor-1254 0.76 20 480 1 7 486

Aroclor-1260 0.76 20 377 69 40 486

PCB Aroclor Results for Bottom Dwellers

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Aroclor-1016 0.68 20 394 1 0 395

Aroclor-1221 0.76 20 395 0 0 395

Aroclor-1232 0.76 20 395 0 0 395

Aroclor-1242 0.76 20 395 0 0 395

Aroclor-1248 0.76 20 383 1 11 395

Aroclor-1254 0.76 20 385 0 10 395

Aroclor-1260 0.76 20 187 49 159 395

Dioxin and Furan Results for Predators

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

2,3,7,8-TCDD 0.01 0.1 297 142 47 486

1,2,3,7,8-PeCDD 0.06 0.5 403 75 8 486

1,2,3,4,7,8-HxCDD 0.06 0.5 471 15 0 486

1,2,3,6,7,8-HxCDD 0.04 0.5 350 128 8 486

1,2,3,7,8,9-HxCDD 0.04 0.5 460 26 0 486

1,2,3,4,6,7,8-HpCDD 0.03 0.5 412 65 9 486

OCDD 0.09 1.0 467 9 10 486

2,3,7,8-TCDF 0.03 0.1 138 189 159 486

1,2,3,7,8-PeCDF 0.04 0.5 453 32 1 486

2,3,4,7,8-PeCDF 0.06 0.5 420 61 5 486

1,2,3,4,7,8-HxCDF 0.04 0.5 458 28 0 486

1,2,3,6,7,8-HxCDF 0.04 0.5 474 12 0 486

1,2,3,7,8,9-HxCDF 0.04 0.5 483 3 0 486

2,3,4,6,7,8-HxCDF 0.06 0.5 478 8 0 486

1,2,3,4,6,7,8-HpCDF 0.05 0.5 474 11 1 486

1,2,3,4,7,8,9-HpCDF 0.05 0.5 486 0 0 486

OCDF 0.2 1.0 476 10 0 486

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-11

Dioxin and Furan Results for Bottom Dwellers

Chemical

MDL

ng/kg (ppt)

ML

ng/kg (ppt)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

2,3,7,8-TCDD 0.01 0.1 76 133 186 395

1,2,3,7,8-PeCDD 0.06 0.5 96 226 73 395

1,2,3,4,7,8-HxCDD 0.06 0.5 166 193 36 395

1,2,3,6,7,8-HxCDD 0.04 0.5 55 209 131 395

1,2,3,7,8,9-HxCDD 0.04 0.5 173 201 21 395

1,2,3,4,6,7,8-HpCDD 0.03 0.5 135 74 186 395

OCDD 0.09 1.0 209 22 164 395

2,3,7,8-TCDF 0.03 0.1 21 67 307 395

1,2,3,7,8-PeCDF 0.04 0.5 176 211 8 395

2,3,4,7,8-PeCDF 0.06 0.5 94 264 37 395

1,2,3,4,7,8-HxCDF 0.04 0.5 225 168 2 395

1,2,3,6,7,8-HxCDF 0.04 0.5 247 147 1 395

1,2,3,7,8,9-HxCDF 0.04 0.5 385 10 0 395

2,3,4,6,7,8-HxCDF 0.06 0.5 306 88 1 395

1,2,3,4,6,7,8-HpCDF 0.05 0.5 236 146 13 395

1,2,3,4,7,8,9-HpCDF 0.05 0.5 391 2 2 395

OCDF 0.2 1.0 360 32 3 395

Organochloride Pesticide Results for Predators

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

2,4'-DDD 0.38 2.0 347 3 2 352†

2,4'-DDE 0.82 2.0 318 17 17 352†

2,4'-DDT 0.38 2.0 334 10 8 352†

4,4'-DDD 0.52 2.0 440 5 41 486

4,4'-DDE 0.74 2.0 112 117 257 486

4,4'-DDT 0.66 2.0 443 10 33 486

Aldrin 2.178 4.0 480 5 1 486

Chlordane, alpha- 1.814 4.0 453 16 17 486

Chlordane, gamma- 0.488 2.0 473 10 3 486

Dicofol 16.24 40.0 471 1 14 486

Dieldrin 0.44 1.0 462 2 22 486

Endosulfan I 1.22 4.0 468 7 11 486

Endosulfan II 10.3 40.0 486 0 0 486

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
F-12

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

Organochloride Pesticide Results for Predators (continued)

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Endosulfan Sulfate 4.16 10.0 469 0 1 470*

Endrin 2.86 10.0 483 1 2 486

Ethalfluralin 1.67 4.0 466 16 4 486

Heptachlor 1.79 2.0 469 0 17 486

Heptachlor Epoxide 0.52 2.0 480 3 3 486

Hexachlorocyclohexane (BHC), 

alpha4.7 10.0 481 5 0 486

Hexachlorocyclohexane (BHC), 

beta1.13 4.0 447 26 13 486

Hexachlorocyclohexane (BHC), 

delta1.5 4.0 479 6 1 486

Hexachlorocyclohexane (BHC), 

gamma0.606 2.0 458 27 1 486

Isodrin 1.58 4.0 470 15 1 486

Kepone 12.23 40.0 426 45 15 486

Methoxychlor 7.106 20.0 477 3 6 486

Mirex 1.52 4.0 476 8 2 486

Nonachlor, cis- 1.95 4.0 463 18 5 486

Nonachlor, trans- 1.48 4.0 430 39 17 486

Octachlorostyrene 0.83 2.0 480 3 3 486

Oxychlordane 1.94 4.0 463 20 3 486

Pendimethalin 6.21 20.0 485 1 0 486

Pentachloroanisole 1.312 4.0 429 56 1 486

Pentachloronitrobenzene 0.76 2.0 457 22 7 486

Permethrin, cis- 25 100.0 481 4 1 486

Permethrin, trans- 21 40.0 481 1 4 486

Toxaphene 20 100.0 486 0 0 486

Trifluralin 2.98 10.0 450 35 1 486

Organochlorine Pesticide Results for Bottom Dwellers

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

2,4'-DDD 0.38 2.0 247 17 10 274†

2,4'-DDE 0.82 2.0 162 55 57 274†

2,4'-DDT 0.38 2.0 246 10 18 274†

4,4'-DDD 0.52 2.0 248 24 123 395

4,4'-DDE 0.74 2.0 8 41 346 395

4,4'-DDT 0.66 2.0 335 20 40 395

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-13

Organochlorine Pesticide Results for Bottom Dwellers (continued)

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Aldrin 2.178 4.0 386 4 5 395

Chlordane, alpha- 1.814 4.0 273 64 58 395

Chlordane, gamma- 0.488 2.0 347 26 22 395

Dicofol 16.24 40.0 387 2 6 395

Dieldrin 0.44 1.0 322 13 60 395

Endosulfan I 1.22 4.0 372 7 16 395

Endosulfan II 10.3 40.0 395 0 0 395

Endosulfan Sulfate 4.16 10.0 376 17 2 395

Endrin 2.86 10.0 381 13 1 395

Ethalfluralin 1.67 4.0 305 36 54 395

Heptachlor 1.79 2.0 371 2 22 395

Heptachlor Epoxide 0.52 2.0 370 16 9 395

Hexachlorocyclohexane (BHC), 

alpha4.7 10.0 387 8 0 395

Hexachlorocyclohexane (BHC), 

beta1.13 4.0 357 26 12 395

Hexachlorocyclohexane (BHC), 

delta1.5 4.0 374 11 10 395

Hexachlorocyclohexane (BHC), 

gamma0.606 2.0 364 20 11 395

Isodrin 1.58 4.0 376 9 10 395

Kepone 12.23 40.0 303 47 45 395

Methoxychlor 7.106 20.0 372 14 9 395

Mirex 1.52 4.0 376 14 5 395

Nonachlor, cis- 1.95 4.0 327 22 46 395

Nonachlor, trans- 1.48 4.0 236 85 74 395

Octachlorostyrene 0.83 2.0 387 7 1 395

Oxychlordane 1.94 4.0 350 27 18 395

Pendimethalin 6.21 20.0 376 13 6 395

Pentachloroanisole 1.312 4.0 303 67 25 395

Pentachloronitrobenzene 0.76 2.0 345 34 16 395

Permethrin, cis- 25 100.0 368 17 10 395

Permethrin, trans- 21 40.0 383 4 8 395

Toxaphene 20 100.0 394 1 0 395

Trifluralin 2.98 10.0 251 84 60 395

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
F-14

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

Organophosphorus Pesticide Results for Predators

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Chlorpyriphos 59 200.0 486 0 0 486

Diazinon 40 100.0 486 0 0 486

Disulfoton 161 500.0 484 0 0 484*

Disulfoton Sulfone 275 1000.0 486 0 0 486

Ethion 254 1000.0 486 0 0 486

Paraoxon 121 500.0 486 0 0 486

Parathion, Ethyl- 125 500.0 486 0 0 486

Terbufos 286 1000.0 486 0 0 486

Terbufos Sulfone 73 200.0 486 0 0 486

Organophosphorus Pesticide Results for Bottom Dwellers

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total

Chlorpyriphos 59 200.0 395 0 0 395

Diazinon 40 100.0 395 0 0 395

Disulfoton 161 500.0 373 0 0 373*

Disulfoton Sulfone 275 1000.0 395 0 0 395

Ethion 254 1000.0 395 0 0 395

Paraoxon 121 500.0 395 0 0 395

Parathion, Ethyl- 125 500.0 395 0 0 395

Terbufos 286 1000.0 395 0 0 395

Terbufos Sulfone 73 200.0 395 0 0 395

Semivolatile Organic Compound Results for Predators

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total‡

1,2,4,5-Tetrachlorobenzene 111 333.0 485 0 0 485

1,2,4-Trichlorobenzene 111 333.0 485 0 0 485

1,2-Dichlorobenzene 111 333.0 485 0 0 485

1,3-Dichlorobenzene 111 333.0 485 0 0 485

1,4-Dichlorobenzene 111 333.0 485 0 0 485

2,4,5-Trichlorophenol 111 333.0 485 0 0 485

2,4,6-Tris (1,1-Dimethylethyl) 

Phenol

111 333.0 485 0 0 485

3,3’-Dichlorobenzidine 555 1665.0 265 0 0 265*

4-Bromophenyl Phenyl Ether 111 333.0 485 0 0 485

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

F-15

Semivolatile Organic Compound Results for Predators (continued)

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total‡

4,4’-Methylene bis 

(2-Chloroaniline)

222 666.0 432 0 0 432*

Acenaphthene 111 333.0 485 0 0 485

Acenaphthylene 111 333.0 485 0 0 485

Anthracene 111 1665.0 485 0 0 485

Benzo(a)Anthracene 111 333.0 485 0 0 485

Benzo(a)Pyrene 111 333.0 485 0 0 485

Benzo(b)Fluoranthene 111 333.0 485 0 0 485

Benzo(ghi)Perylene 222 666.0 485 0 0 485

Benzo(j)Fluoranthene 111 333.0 485 0 0 485

Benzo(k)Fluoranthene 111 333.0 485 0 0 485

Bis (2-ethylhexyl) Phthalate 111 333.0 479 3 3 485

Butyl Benzyl Phthalate 111 333.0 482 1 2 485

Chrysene 111 333.0 485 0 0 485

Di-n-Butyl Phthalate 111 333.0 451 29 5 485

Dibenz(a,h)Anthracene 111 333.0 485 0 0 485

Diethylstilbestrol 111 333.0 435 0 0 485

Fluoranthene 111 333.0 485 0 0 485

Fluorene 111 333.0 485 0 0 485

Hexachlorobenzene 111 333.0 485 0 0 485

Hexachlorobutadiene 111 333.0 485 0 0 485

Indeno(1,2,3-cd)Pyrene 222 666.0 485 0 0 485

Naphthalene 111 333.0 485 0 0 485

Nitrobenzene 111 333.0 485 0 0 485

Nonylphenol 111 333.0 479 6 0 485

Pentachlorobenzene 222 666.0 485 0 0 485

Pentachlorophenol 555 1665.0 481 0 0 481*

Perylene 111 333.0 485 0 0 485

Phenanthrene 111 333.0 484 0 0 484*

Phenol 111 333.0 485 0 0 485

Pyrene 111 333.0 484 1 0 485

Tetrabromobisphenol A 5550 16650.0 429 0 0 429*

‡ There were only 485 predator samples analyzed for the semivolatile organics.

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
F-16

The National Study of Chemical Residues in Lake Fish Tissue

Appendix F: Occurrence of Target Chemicals

Semivolatile Organic Compound Results for Bottom Dwellers

Chemical

MDL

μg/kg (ppb)

ML

μg/kg (ppb)

Number of Concentration Values

< MDL ≥ MDL & < ML ≥ ML Total‡

1,2,4,5-Tetrachlorobenzene 111 333.0 395 0 0 395

1,2,4-Trichlorobenzene 111 333.0 395 0 0 395

1,2-Dichlorobenzene 111 333.0 395 0 0 395

1,3-Dichlorobenzene 111 333.0 395 0 0 395

1,4-Dichlorobenzene 111 333.0 395 0 0 395

2,4,5-Trichlorophenol 111 333.0 395 0 0 395

2,4,6-Tris(1,1-Dimethylethyl) 

Phenol

111 333.0 395 0 0 395

3,3’-Dichlorobenzidine 555 1665.0 131 0 0 131*

4-Bromophenyl Phenyl Ether 111 333.0 395 0 0 395

4,4’-Methylene bis(2-Chloroaniline) 222 666.0 377 0 0 377*

Acenaphthene 111 333.0 395 0 0 395

Acenaphthylene 111 333.0 395 0 0 395

Anthracene 111 1665.0 395 0 0 395

Benzo(a)Anthracene 111 333.0 395 0 0 395

Benzo(a)Pyrene 111 333.0 395 0 0 395

Benzo(b)Fluoranthene 111 333.0 394 0 0 394*

Benzo(ghi)Perylene 222 666.0 395 0 0 395

Benzo(j)Fluoranthene 111 333.0 395 0 0 395

Benzo(k)Fluoranthene 111 333.0 394 0 0 394*

Bis (2-ethylhexyl) Phthalate 111 333.0 384 11 0 395

Butyl Benzyl Phthalate 111 333.0 394 1 0 395

Chrysene 111 333.0 395 0 0 395

Di-n-Butyl Phthalate 111 333.0 368 21 6 395

Dibenz(a,h)Anthracene 111 333.0 395 0 0 395

Diethylstilbestrol 111 333.0 308 0 0 308*

Fluoranthene 111 333.0 395 0 0 395

Fluorene 111 333.0 395 0 0 395

Hexachlorobenzene 111 333.0 395 0 0 395

Hexachlorobutadiene 111 333.0 395 0 0 395

Indeno(1,2,3-cd)Pyrene 222 666.0 395 0 0 395

Naphthalene 111 333.0 394 1 0 395

Nitrobenzene 111 333.0 395 0 0 395

Nonylphenol 111 333.0 394 1 0 395

Pentachlorobenzene 222 666.0 395 0 0 395

Pentachlorophenol 555 1665.0 373 0 0 373*

Perylene 111 333.0 395 0 0 395

Phenanthrene 111 333.0 395 0 0 395

Phenol 111 333.0 387 5 0 387*

Pyrene 111 333.0 395 0 0 395

Tetrabromobisphenol A 5550 16650.0 261 0 0 261*

* Some results were excluded from the database due to QC failures. Therefore, the total number may be less for some target 

chemicals within the same analytical class.

† These chemicals were not analyzed during the first year of the study.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G

Cumulative Distribution Functions

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-1

Mercury CDFs . . . . . . . . . . . . . . . . . . . . . . . . G-2

PCB CDFs............................ G-4

Dioxin and Furan CDFs . . . . . . . . . . . . . . . . . G-6

DDT CDFs . . . . . . . . . . . . . . . . . . . . . . . . . . G-12

Chlordane CDFs . . . . . . . . . . . . . . . . . . . . . G-14
G-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

Mercury CDFs
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-3

Mercury CDFs
G-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

PCB CDFs
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-5

PCB CDFs
G-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

Dioxin and Furan CDFs
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-7

Dioxin and Furan CDFs
G-8

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

Dioxin and Furan CDFs
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-9

Dioxin and Furan CDFs
G-10

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

Dioxin and Furan CDFs
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-11

Dioxin and Furan CDFs
G-12

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

DDT CDFs
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-13

DDT CDFs
G-14

The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

Chlordane CDFs
The National Study of Chemical Residues in Lake Fish Tissue

Appendix G: Cumulative Distribution Functions

G-15

Chlordane CDFs

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H

Detection Agreement between 

Replicate Sample Pairs

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

H-1

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Metals

Mercury

Mercury 70 0 0 100 52 0 0 100

Arsenic

Arsenate 0 69 1 99 0 52 0 100

Arsenite 0 70 0 100 7 39 6 88

Total Inorganic Arsenic 0 70 0 100 3 43 6 88

Dimethylarsonic Acid 1 68 1 99 0 52 0 100

Monomethylarsonic Acid 0 69 1 99 0 52 0 100

PCB

s

PCB-1 3 64 3 96

4 39 9 83

PCB-2 2 67 1 99 8 39 5 90

PCB-3 15 40 15 79 7 32 13 75

PCB-4 27 32 11 84 33 14 5 90PCB-5 0 68 2 97

4 45 3 94

PCB-6 16 39 15 79 36 11 5 90

PCB-7 5 53 12 83 15 24 13 75

PCB-8 19 36 15 79 40 7 5 90

PCB-9 2 67 1 99 16 25 11 79

PCB-10 0 67 3 96

4 45 3 94

PCB-11 30 30 10 86 32 15 5 90PCB-12+PCB-13 0 66

4 94 6 41 5 90

PCB-14 0 70 0 100 0 51 1 98

PCB-15 35 28 7 90 45 6 1 98

PCB-16 38 21 11 84 47 2 3 94
H-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

PCB

s (continued)

PCB-17 49 15 6 91 46 3 3 94

PCB-18+PCB-30 50 14 6 91 49 0 3 94

PCB-19 38 16 16 77 43 5 4 92

PCB-20+PCB-28 59 8 3 96 52 0 0 100

PCB-21+PCB-33 55 10 5 93 48 1 3 94

PCB-22 62

4

4 94 50 2 0 100

PCB-23 0 67 3 96 3 47 2 96

PCB-24

4 64 2 97 14 30 8 85

PCB-25 34 25 11 84 44 6 2 96

PCB-26+PCB-29 13 50 7 90 38 9 5 90

PCB-27 12 51 7 90 35 12 5 90

PCB-31 58 5 7 90 50 2 0 100

PCB-32 33 23 14 80 44 1 7 87

PCB-34 5 58 7 90 28 18 6 88

PCB-35 0 70 0 100 1 51 0 100

PCB-36 0 70 0 100 1 51 0 100

PCB-37 61 2 7 90 48

4 0 100

PCB-38 1 67 2 97 6 39 7 87

PCB-39 3 60 7 90 18 25 9 83

PCB-40+PCB-41+PCB-71 59 8 3 96 49 1 2 96

PCB-42 61 6 3 96 51 0 1 98

PCB-43 14 45 11 84 36 12

4 92

PCB-44+PCB-47+PCB-65 60

4 6 91 51 0 1 98

PCB-45+PCB-51 22 39 9 87 39 6 7 87
The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

H-3

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

PCB

s (continued)

PCB-46 9 57

4 94 31 16 5 90

PCB-48 56 10

4 94 48 2 2 96

PCB-49+PCB-69 65 1 4 94 52 0 0 100PCB-50+PCB-53 10 53 7 90 29 15 8 85

PCB-52 65 3 2 97 52 0 0 100PCB-54 2 66 2 97 6 40 6 88

PCB-55 5 58 7 90 5 35 12 77

PCB-56 66 2 2 97 51 0 1 98

PCB-57 10 52 8 89 26 18 8 85

PCB-58 12 46 12 83 33 13 6 88

PCB-59+PCB-62+PCB-75 39 20 11 84 45 3 4 92

PCB-60 67 1 2 97 52 0 0 100

PCB-61+PCB-70+PCB-74+ PCB-76

70 0 0 100 52 0 0 100

PCB-63 54 8 8 89 51 1 0 100PCB-64 67 0 3 96 52 0 0 100

PCB-66 64 6 0 100 52 0 0 100

PCB-67 41 21 8 89 43 6 3 94

PCB-68 49 12 9 87 50 0 2 96PCB-72 46 18 6 91 46

4 2 96

PCB-73 0 67 3 96 2 49 1 98

PCB-77 21 40 9 87 34 12 6 88

PCB-78 0 69 1 99 1 51 0 100

PCB-79 36 22 12 83 43 5 4 92
H-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

PCB

s (continued)

PCB-80 0 70 0 100 1 49 2 96

PCB-81 7 51 12 83 28 12 12 77

PCB-82 63 5 2 97 51 1 0 100

PCB-83+PCB-99 70 0 0 100 52 0 0 100

PCB-84 62 5 3 96 50 1 1 98

PCB-85+PCB-116+PCB-117 69 0 1 99 52 0 0 100

PCB-86+PCB-87+PCB-97+ PCB-108+PCB-119+PCB-125

65 2 3 96 52 0 0 100

PCB-88+PCB-91 65

4 1 99 51 0 1 98

PCB-89 9 52 9 87 30 14 8 85

PCB-90+PCB-101+PCB-113 69 0 1 99 52 0 0 100

PCB-92 68 0 2 97 52 0 0 100PCB-93+PCB-95+PCB-98+ PCB-100+PCB-102

68 1 1 99 51 0 1 98

PCB-94 3 59 8 89 24 19 9 83

PCB-96 3 65 2 97 15 31 6 88

PCB-103 45 16 9 87 44 3 5 90

PCB-104 0 69 1 99 2 50 0 100

PCB-105 65

4 1 99 52 0 0 100

PCB-106 0 70 0 100 0 52 0 100

PCB-107+PCB-124 61

4 5 93 51 1 0 100

PCB-109 66 2 2 97 52 0 0 100

PCB-110+PCB-115 69 0 1 99 52 0 0 100

PCB-111 27 35 8 89 37 8 7 87

PCB-112 0 70 0 100 0 52 0 100
The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

H-5

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

PCB

s (continued)

PCB-114 62

4

4 94 52 0 0 100

PCB-118 67 1 2 97 52 0 0 100

PCB-120 56 8 6 91 48 2 2 96

PCB-121 13 52 5 93 25 18 9 83

PCB-122 32 24 14 80 48 2 2 96PCB-123 54 9 7 90 51 1 0 100PCB-126

4 63 3 96 16 32

4 92

PCB-127 21 39 10 86 29 13 10 81

PCB-128+PCB-166 65

4 1 99 52 0 0 100

PCB-129+PCB138+PCB-160 +PCB-163

70 0 0 100 52 0 0 100

PCB-130 68 1 1 99 52 0 0 100PCB-131 39 21 10 86 43 5 4 92

PCB-132 66 0 4 94 52 0 0 100

PCB-133 62 3 5 93 51 1 0 100

PCB-134+PCB-143 58 6 6 91 51 1 0 100

PCB-135+PCB-151+PCB-154 65

4 1 99 52 0 0 100

PCB-136 59 5 6 91 51 1 0 100

PCB-137 67 1 2 97 52 0 0 100

PCB-139+PCB-140 60 6 4 94 51 0 1 98

PCB-141 69 0 1 99 51 0 1 98

PCB-142 0 70 0 100 0 52 0 100

PCB-144 55 5 10 86 50 1 1 98

PCB-145 0 69 1 99 5 44 3 94
H-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

PCB

s (continued)

PCB-146 70 0 0 100 52 0 0 100

PCB-147+PCB-149 69 0 1 99 52 0 0 100

PCB-148 33 29 8 89 37 10 5 90

PCB-150 22 40 8 89 33 12 7 87PCB-152 1 67 2 97 16 28 8 85

PCB-153+PCB-168 70 0 0 100 52 0 0 100

PCB-155 28 35 7 90 30 15 7 87

PCB-156+PCB-157 67 0 3 96 52 0 0 100

PCB-158 69 0 1 99 52 0 0 100

PCB-159 49 11 10 86 44 0 8 85

PCB-161 0 70 0 100 0 52 0 100

PCB-162 55 10 5 93 45 2 5 90

PCB-164 67 0 3 96 52 0 0 100

PCB-165 18 40 12 83 26 14 12 77

PCB-167 68 0 2 97 52 0 0 100PCB-169 10 52 8 89 30 12 10 81

PCB-170 66

4 0 100 52 0 0 100

PCB-171+PCB-173 66 2 2 97 52 0 0 100

PCB-172 67 2 1 99 52 0 0 100

PCB-174 68 0 2 97 52 0 0 100PCB-175 56 6 8 89 52 0 0 100PCB-176 55 9 6 91 51 0 1 98

PCB-177 69 0 1 99 52 0 0 100

PCB-178 66 3 1 99 52 0 0 100
The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

H-7

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

PCB

s (continued)

PCB-179 63 2 5 93 49 0 3 94

PCB-180+PCB-193 67 2 1 99 52 0 0 100

PCB-181 40 17 13 81 42

4 6 88

PCB-182 45 17 8 89 41 2 9 83

PCB-183+PCB-185 68 0 2 97 52 0 0 100PCB-184 28 37 5 93 32 10 10 81

PCB-186 0 70 0 100 0 52 0 100

PCB-187 67 2 1 99 52 0 0 100

PCB-188 5 62 3 96 15 33

4 92

PCB-189 63 6 1 99 51 1 0 100

PCB-190 65 2 3 96 52 0 0 100PCB-191 55 7 8 89 52 0 0 100

PCB-192 1 69 0 100

4 44

4 92

PCB-194 67 2 1 99 52 0 0 100

PCB-195 53 11 6 91 47

4 1 98

PCB-196 66 3 1 99 51 0 1 98

PCB-197+PCB-200 56 7 7 90 50 0 2 96PCB-198+PCB-199 69 0 1 99 51 0 1 98

PCB-201 36 25 9 87 43 5 4 92

PCB-202 64 3 3 96 51 0 1 98

PCB-203 66 1 3 96 51 1 0 100

PCB-204 6 59 5 93 21 28 3 94

PCB-205 57 8 5 93 51 1 0 100

PCB-206 63 6 1 99 51 0 1 98
H-8

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

PCB

s (continued)

PCB-207 65 3 2 97 52 0 0 100PCB-208 66 1 3 96 52 0 0 100

PCB-209 55 7 8 89 50 1 1 98

Dioxi

n

s

a

n

d

Fura

n

s

2,3,7,8-TCDD 14 36 20 71 39

4 9 83

1,2,3,7,8-PeCDD 11 54 5 93 38 6 8 851,2,3,4,7,8-HxCDD 1 65

4 94 24 16 12 77

1,2,3,6,7,8-HxCDD 13 46 11 84 46 2 4 92

1,2,3,7,8,9-HxCDD

4 60 6 91 24 21 7 87

1,2,3,4,6,7,8-HpCDD

4 56 10 86 28 13 11 79

OCDD 0 68 2 97 18 28 6 88

2,3,7,8-TCDF 48 15 7 90 50 2 0 100

1,2,3,7,8-PeCDF

4 63 3 96 16 21 15 71

2,3,4,7,8-PeCDF 5 58 7 90 36 7 9 83

1,2,3,4,7,8-HxCDF 0 64 6 91 10 28 14 73

1,2,3,6,7,8-HxCDF 0 66

4 94 13 29 10 81

1,2,3,7,8,9-HxCDF 0 69 1 99 0 52 0 100

2,3,4,6,7,8-HxCDF 0 70 0 100 8 39 5 90

1,2,3,4,6,7,8-HpCDF 0 67 3 96 12 25 15 71

1,2,3,4,7,8,9-HpCDF 0 69 1 99 0 51 1 98

OCDF 0 70 0 100 2 48 2 96

Orga

n

o

chlori

n

e Pesti

cides: Total DDT

2,4'-DDD 0 57 0 100 1 36 2 95

2,4'-DDE 1 52

4 93 13 21 5 87
The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

H-9

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Orga

n

o

chlori

n

e Pesti

cides: Total DDT (continued)

2,4'-DDT 2 54 1 98 3 34 2 954,4'-DDD 1 68 1 99 12 27 13 75

4,4'-DDE 45 16 9 87 51 1 0 100

4,4'-DDT 1 61 8 89

4 36 12 77

Orga

n

o

chlori

n

e Pesti

cides: Total Chlorda

n

e

Chlordane, alpha- 1 65

4 94 15 32 5 90

Chlordane, gamma- 1 69 0 100

4 44

4 92

Nonachlor, cis- 1 68 1 99 8 38 6 88

Nonachlor, trans- 1 64 5 93 20 29 3 94Oxychlordane 1 66 3 96 3 45

4 92

Other

Orga

n

o

chlori

n

e Pesti

cides

Aldrin 0 69 1 99 0 52 0 100

Dicofol 1 68 1 99 0 49 3 94

Dieldrin 2 67 1 99 11 39 2 96

Endosulfan I 0 66

4 94 1 49 2 96

Endosulfan II 0 70 0 100 0 52 0 100

Endosulfan Sulfate 0 70 0 100 0 50 2 96

Endrin 0 69 1 99 3 47 2 96Ethalfluralin 0 66

4 94 1 38 13 75

Heptachlor 1 64 5 93

4 44

4 92

Heptachlor Epoxide 1 69 0 100 2 46

4 92

Hexachlorocyclohexane (BHC), alpha0 70 0 100 0 50 2 96

Hexachlorocyclohexane (BHC), beta1 59 10 86 1 41 10 81
H-10

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Other

Orga

n

o

chlori

n

e Pesti

cides (continued)

Hexachlorocyclohexane (BHC), delta0 69 1 99 1 48 3 94

Hexachlorocyclohexane (BHC), gamma3 63

4 94 2 44 6 88

Isodrin 0 65 5 93 0 49 3 94

Kepone 3 56 11 84 8 36 8 85

Methoxychlor 0 69 1 99 1 49 2 96

Mirex 0 68 2 97 2 49 1 98

Octachlorostyrene 0 69 1 99 0 49 3 94Pendimethalin 0 70 0 100 2 46

4 92

Pentachloroanisole 3 50 17 76 9 37 6 88

Pentachloronitrobenzene 0 63 7 90 5 45 2 96

Permethrin, cis- 0 68 2 97 1 48 3 94Permethrin, trans- 0 70 0 100 0 49 3 94Toxaphene 0 70 0 100 0 52 0 100

Trifluralin 2 63 5 93 7 31 14 73

Orga

n

o

phos

phorous Pesti

cides

Chlorpyriphos 0 70 0 100 0 52 0 100

Diazinon 0 70 0 100 0 52 0 100

Disulfoton 0 70 0 100 0 52 0 100

Disulfoton Sulfone 0 70 0 100 0 52 0 100

Ethion 0 70 0 100 0 52 0 100

Paraoxon 0 70 0 100 0 52 0 100

Parathion, Ethyl- 0 70 0 100 0 52 0 100

Terbufos 0 70 0 100 0 52 0 100
The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

H-11

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Orga

n

o

phos

phorous Pesti

cides (continued)

Terbufos Sulfone 0 70 0 100 0 52 0 100

Semivolatile

Orga

nic Com

pou

nds: PAH

s

Acenaphthene 0 70 0 100 0 52 0 100

Anthracene 0 70 0 100 0 52 0 100

Benzo(a)Anthracene 0 70 0 100 0 52 0 100

Benzo(a)Pyrene 0 70 0 100 0 52 0 100

Benzo(b)Fluoranthene 0 70 0 100 0 52 0 100

Benzo(ghi)Perylene 0 70 0 100 0 52 0 100

Benzo(j)Fluoranthene 0 70 0 100 0 52 0 100

Benzo(k)Fluoranthene 0 70 0 100 0 52 0 100

Chrysene 0 70 0 100 0 52 0 100

Dibenzo(a,h)Anthracene 0 70 0 100 0 52 0 100

Fluoranthene 0 70 0 100 0 52 0 100

Fluorene 0 70 0 100 0 52 0 100

Indeno(1,2,3-cd)Pyrene 0 70 0 100 0 52 0 100

Naphthalene 0 69 1 99 0 52 0 100

Perylene 0 70 0 100 0 52 0 100

Phenanthrene 0 70 0 100 0 52 0 100

Pyrene 0 70 0 100 0 52 0 100

Other

Semivolatile

Orga

nic Com

pou

nds

1,2,4,5-Tetrachlorobenzene 0 70 0 100 0 52 0 100

1,2,4-Trichlorobenzene 0 70 0 100 0 52 0 100

1,2-Dichlorobenzene 0 70 0 100 0 52 0 100

1,3-Dichlorobenzene 0 70 0 100 0 52 0 100
H-12

The National Study of Chemical Residues in Lake Fish Tissue

Appendix H: Detection Agreement between Replicate Sample Pairs

Chemi

cal

Predators (N=70 

Sam

ples) Bottom

Dwellers (N=52 

Sam

ples)

Both

a

bove

Dete

ctio

n

Both

below

Dete

ctio

n

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Dete

ctio

n

Results

Differ

Per

cen

t

Agreeme

n

t

Other

Semivolatile

Orga

nic Com

pou

nds (continued)

1,4-Dichlorobenzene 0 70 0 100 0 52 0 100

2,4,5-Trichlorophenol 0 70 0 100 0 52 0 100

2,4,6-Tris(1,1-Dimethylethyl) Phenol

0 70 0 100 0 52 0 100

3,3'-dichlorobenzidine*

4-Bromophenyl Phenyl Ether

0 70 0 100 0 52 0 100

4,4’-Methylene bis (2-Chloroaniline)

0 70 0 100 0 52 0 100

Acenaphthylene 0 70 0 100 0 52 0 100

Bis (2-ethylhexyl) Phthalate 0 69 1 99 0 50 2 96Butyl Benzyl Phthalate 0 70 0 100 0 52 0 100

Di-n-Butyl Phthalate 0 66

4 94 2 47 3 94

Diethylstilbestrol 0 70 0 100 0 52 0 100

Hexachlorobenzene 0 70 0 100 0 52 0 100

Hexachlorobutadiene 0 70 0 100 0 52 0 100

Nitrobenzene 0 70 0 100 0 52 0 100

Nonylphenol 1 69 0 100 0 52 0 100

Pentachlorobenzene 0 70 0 100 0 52 0 100

Pentachlorophenol 0 70 0 100 0 52 0 100

Phenol 0 70 0 100 0 52 0 100

Tetrabromobisphenol A 0 70 0 100 0 52 0 100

* 3,3’-dichlorobenzidine was originally included as a target analyte in this study. However, the nature of this compound often results in poor recoveries from tissue samples and 

Ongoing Precision and Recovery (OPR) samples. Historically, the recovery problems have led to exclusion of large numbers of analytical results for 3,3’-dichlorobenzidine. Therefore, rather than exclude a large percentage of these results and include other results for this compound with recoveries that are very disparate from the other target analytes, EPA decided not to report results for 3,3’-dichlorobenzidine.
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I

Tissue Concentration Differences 

between Replicate Sample Pairs

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-1

Ta

b

le I-1. Metals

Tissue Concentration Differences for Predators (Fillets)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Mercury

Mercury ppb 70 1.7 410.0 11.00 21.75 48.50 84.75 162.50

Arsenic

Arsenate ppm 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Arsenite ppm 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Inorganic arsenic (Total) ppm 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Dimethylarsonic Acid ppm 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Monomethylarsonic Acid ppm 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Mercury

Mercury ppb 52 0.1 130.9 3.81 5.32 11.80 37.43 90.83

Arsenic

Arsenate ppm 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Arsenite ppm 52 0.0 0.1 0.00 0.00 0.00 0.00 0.02

Inorganic arsenic (Total) ppm 52 0.0 0.1 0.00 0.00 0.00 0.00 0.01

Dimethylarsonic Acid ppm 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Monomethylarsonic Acid ppm 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00
I-2

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-2. PC

B

s

Tissue Concentration Differences for Predators (Fillets)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 1 ppt 70 0.0 6.0 0.00 0.00 0.00 0.00 0.00

PCB 2 ppt 70 0.0 1.8 0.00 0.00 0.00 0.00 0.00

PCB 3 ppt 70 0.0 5.6 0.00 0.00 0.00 0.20 1.01

PCB 4 ppt 70 0.0 265.5 0.00 0.00 0.00 0.28 0.72

PCB 5 ppt 70 0.0 3.1 0.00 0.00 0.00 0.00 0.00

PCB 6 ppt 70 0.0 400.6 0.00 0.00 0.00 0.10 0.31

PCB 7 ppt 70 0.0 9.6 0.00 0.00 0.00 0.00 0.40

PCB 8 ppt 70 0.0 465.7 0.00 0.00 0.00 0.48 1.11

PCB 9 ppt 70 0.0 27.0 0.00 0.00 0.00 0.00 0.00

PCB 10 ppt 70 0.0 8.4 0.00 0.00 0.00 0.00 0.00

PCB 11 ppt 70 0.0 128.0 0.00 0.00 0.00 0.40 2.43

PCB 12 + PCB 13 ppt 70 0.0 18.5 0.00 0.00 0.00 0.00 0.00

PCB 14 ppt 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 15 ppt 70 0.0 817.5 0.00 0.00 0.05 0.30 1.10

PCB 16 ppt 70 0.0 188.0 0.00 0.00 0.15 0.60 2.41

PCB 17 ppt 70 0.0 485.7 0.00 0.10 0.40 1.08 3.91

PCB 18 + PCB 30 ppt 70 0.0 1465.7 0.00 0.13 0.60 1.85 5.15

PCB 19 ppt 70 0.0 120.7 0.00 0.00 0.10 0.20 0.62

PCB 20 + PCB 28 ppt 70 0.0 7842.7 0.00 0.80 2.85 8.90 34.33

PCB 21 + PCB 33 ppt 70 0.0 650.3 0.00 0.10 0.55 2.00 4.50

PCB 22 ppt 70 0.0 504.2 0.09 0.20 0.90 2.08 5.24PCB 23 ppt 70 0.0 2.8 0.00 0.00 0.00 0.00 0.00

PCB 24 ppt 70 0.0 10.9 0.00 0.00 0.00 0.00 0.00

PCB 25 ppt 70 0.0 145.4 0.00 0.00 0.10 0.40 3.00

PCB 26 + PCB 29 ppt 70 0.0 573.5 0.00 0.00 0.00 0.20 4.64
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-3

Ta

b

le I-2. PC

B

s (continued)

Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 27 ppt 70 0.0 97.9 0.00 0.00 0.00 0.00 0.70

PCB 31 ppt 70 0.0 2012.7 0.10 0.93 2.60 7.00 21.30

PCB 32 ppt 70 0.0 223.6 0.00 0.00 0.10 0.50 2.05PCB 34 ppt 70 0.0 14.0 0.00 0.00 0.00 0.00 0.10

PCB 35 ppt 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 36 ppt 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 37 ppt 70 0.0 1162.5 0.00 0.10 0.30 0.88 2.18

PCB 38 ppt 70 0.0 3.5 0.00 0.00 0.00 0.00 0.00

PCB 39 ppt 70 0.0 11.6 0.00 0.00 0.00 0.00 0.20

PCB 40 + PCB 41 + PCB 71 ppt 70 0.0 841.0 0.00 0.23 1.30 3.38 14.65

PCB 42 ppt 70 0.0 628.0 0.00 0.33 1.10 2.60 12.72

PCB 43 ppt 70 0.0 132.6 0.00 0.00 0.00 0.18 1.91

PCB 44 + PCB 47 + PCB 65 ppt 70 0.0 2660.0 0.47 3.00 5.10 14.48 62.57

PCB 45 + PCB 51 ppt 70 0.0 209.6 0.00 0.00 0.00 0.75 5.11

PCB 46 ppt 70 0.0 44.0 0.00 0.00 0.00 0.00 0.63

PCB 48 ppt 70 0.0 403.2 0.00 0.13 0.50 1.70 6.46PCB 49 + PCB 69 ppt 70 0.0 2059.0 0.30 1.53 4.00 16.68 51.61

PCB 50 + PCB 53 ppt 70 0.0 248.8 0.00 0.00 0.00 0.00 2.87

PCB 52 ppt 70 0.0 4151.0 0.60 3.35 7.50 22.90 83.80

PCB 54 ppt 70 0.0 7.9 0.00 0.00 0.00 0.00 0.00

PCB 55 ppt 70 0.0 30.1 0.00 0.00 0.00 0.00 0.64

PCB 56 ppt 70 0.0 473.0 0.19 0.33 1.40 5.28 11.80

PCB 57 ppt 70 0.0 13.6 0.00 0.00 0.00 0.00 0.51

PCB 58 ppt 70 0.0 32.5 0.00 0.00 0.00 0.18 0.60
I-4

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

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B

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Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 59 + PCB 62 + PCB 75 ppt 70 0.0 373.0 0.00 0.00 0.40 1.38 6.05

PCB 60 ppt 70 0.0 1108.8 0.19 0.80 1.70 4.78 12.73PCB 61 + PCB 70 + PCB 74 + PCB 76 ppt 70 0.1 3870.8 1.24 6.00 16.85 47.05 131.00

PCB 63 ppt 70 0.0 115.7 0.00 0.20 0.70 1.78 4.97PCB 64 ppt 70 0.0 1226.0 0.20 0.73 2.20 6.43 28.89

PCB 66 ppt 70 0.0 3911.0 0.00 3.93 12.35 28.75 74.22

PCB 67 ppt 70 0.0 80.5 0.00 0.00 0.20 0.60 1.83

PCB 68 ppt 70 0.0 82.2 0.00 0.10 0.30 0.80 3.01

PCB 72 ppt 70 0.0 93.0 0.00 0.00 0.30 0.98 3.11

PCB 73 ppt 70 0.0 0.5 0.00 0.00 0.00 0.00 0.00

PCB 77 ppt 70 0.0 270.1 0.00 0.00 0.00 0.98 4.62

PCB 78 ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.00

PCB 79 ppt 70 0.0 64.6 0.00 0.00 0.20 0.88 3.18PCB 80 ppt 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 81 ppt 70 0.0 19.7 0.00 0.00 0.00 0.00 0.30

PCB 82 ppt 70 0.0 286.0 0.09 0.33 1.50 4.23 12.07

PCB 83 + PCB 99 ppt 70 0.0 5910.0 3.76 12.05 32.10 90.00 293.10

PCB 84 ppt 70 0.0 569.0 0.10 0.43 1.50 5.85 17.11

PCB 85 + PCB 116 + PCB 117 ppt 70 0.0 1070.0 0.80 3.00 8.40 21.78 74.14PCB 86 + PCB 87 + PCB 97 + PCB 108 + PCB 119 + PCB 125 ppt 70 0.0 2850.0 1.09 4.75 19.70 50.75 162.89

PCB 88 + PCB 91 ppt 70 0.0 991.0 0.10 0.45 2.25 6.25 35.34

PCB 89 ppt 70 0.0 18.5 0.00 0.00 0.00 0.00 0.53
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-5

Ta

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B

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Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 90 + PCB 101 + PCB 113 ppt 70 0.1 5370.0 3.94 14.08 34.85 110.50 311.50

PCB 92 ppt 70 0.0 1970.0 0.79 2.63 5.75 25.30 71.54

PCB 93 + PCB 95 + PCB 98 + PCB 100 + PCB 102 ppt 70 0.0 3210.0 0.68 2.75 7.25 36.00 132.70

PCB 94 ppt 70 0.0 12.4 0.00 0.00 0.00 0.00 0.21

PCB 96 ppt 70 0.0 10.3 0.00 0.00 0.00 0.00 0.00

PCB 103 ppt 70 0.0 160.3 0.00 0.00 0.30 0.80 4.11

PCB 104 ppt 70 0.0 3.9 0.00 0.00 0.00 0.00 0.00

PCB 105 ppt 70 0.0 881.0 0.58 4.45 16.70 38.55 119.39

PCB 106 ppt 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 107 + PCB 124 ppt 70 0.0 109.5 0.10 0.40 1.50 3.90 9.94

PCB 109 ppt 70 0.0 528.0 0.50 1.60 4.80 13.03 27.77

PCB 110 + PCB 115 ppt 70 0.0 4680.0 1.77 4.30 23.40 87.15 253.90

PCB 111 ppt 70 0.0 20.1 0.00 0.00 0.00 0.30 0.63

PCB 112 ppt 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 114 ppt 70 0.0 76.0 0.00 0.30 1.10 3.25 8.67

PCB 118 ppt 70 0.0 3860.0 5.60 15.70 48.00 117.25 342.30

PCB 120 ppt 70 0.0 151.6 0.00 0.20 0.75 2.05 4.41

PCB 121 ppt 70 0.0 14.0 0.00 0.00 0.00 0.00 0.31

PCB 122 ppt 70 0.0 39.9 0.00 0.00 0.30 0.70 1.81PCB 123 ppt 70 0.0 67.8 0.00 0.30 1.05 3.38 5.98

PCB 126 ppt 70 0.0 13.9 0.00 0.00 0.00 0.00 0.00

PCB 127 ppt 70 0.0 6.9 0.00 0.00 0.00 0.20 0.73

PCB 128 + PCB 166 ppt 70 0.0 1027.0 0.70 3.43 12.65 34.93 94.53
I-6

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

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B

s (continued)

Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 129 + PCB 138 + PCB 160 + PCB 163 ppt 70 0.1 11730.0 9.99 34.50 111.00 242.00 705.20

PCB 130 ppt 70 0.0 706.0 0.20 1.38 5.10 15.20 28.09

PCB 131 ppt 70 0.0 48.1 0.00 0.00 0.25 0.90 2.24

PCB 132 ppt 70 0.0 1340.0 0.57 1.65 6.95 18.68 51.12

PCB 133 ppt 70 0.0 383.0 0.19 0.60 1.95 5.40 19.31

PCB 134 + PCB 143 ppt 70 0.0 214.0 0.09 0.23 1.30 2.88 8.81

PCB 135 + PCB 151 + PCB 154 ppt 70 0.0 5140.0 1.44 4.03 14.45 37.70 122.00

PCB 136 ppt 70 0.0 467.0 0.00 0.30 1.50 4.28 14.85PCB 137 ppt 70 0.0 275.0 0.58 1.23 4.30 9.85 26.33

PCB 139 + PCB 140 ppt 70 0.0 241.0 0.09 0.40 1.50 4.08 8.88

PCB 141 ppt 70 0.0 1081.0 1.18 4.00 9.00 23.25 54.16

PCB 142 ppt 70 0.0 4.5 0.00 0.00 0.00 0.00 0.00

PCB 144 ppt 70 0.0 319.0 0.00 0.53 1.95 4.90 10.96

PCB 145 ppt 70 0.0 4.5 0.00 0.00 0.00 0.00 0.00

PCB 146 ppt 70 0.0 4380.0 2.91 9.43 24.65 57.70 143.90

PCB 147 + PCB 149 ppt 70 0.0 9150.0 3.08 8.68 34.30 87.75 228.20

PCB 148 ppt 70 0.0 84.6 0.00 0.00 0.10 0.50 2.01

PCB 150 ppt 70 0.0 30.3 0.00 0.00 0.00 0.20 0.80

PCB 152 ppt 70 0.0 3.6 0.00 0.00 0.00 0.00 0.00

PCB 153 + PCB 168 ppt 70 0.0 18400.0 11.52 44.53 122.50 277.48 776.20PCB 155 ppt 70 0.0 103.7 0.00 0.00 0.00 0.28 0.70PCB 156 + PCB 157 ppt 70 0.0 543.0 0.94 2.65 8.25 21.78 48.20PCB 158 ppt 70 0.0 714.0 0.69 2.55 8.30 16.65 39.40
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-7

Ta

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B

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Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 159 ppt 70 0.0 86.8 0.00 0.10 0.65 1.73 3.16

PCB 161 ppt 70 0.0 4.5 0.00 0.00 0.00 0.00 0.00

PCB 162 ppt 70 0.0 44.5 0.00 0.20 0.75 1.40 3.07

PCB 164 ppt 70 0.0 604.0 0.39 0.93 3.20 11.00 23.17PCB 165 ppt 70 0.0 14.6 0.00 0.00 0.00 0.28 0.83

PCB 167 ppt 70 0.0 351.0 0.30 1.35 4.70 9.95 25.71

PCB 169 ppt 70 0.0 2.2 0.00 0.00 0.00 0.00 0.20

PCB 170 ppt 70 0.0 2710.0 1.63 7.40 19.45 56.28 112.50

PCB 171 + PCB 173 ppt 70 0.0 931.0 0.68 1.63 5.65 14.00 32.19PCB 172 ppt 70 0.0 663.0 0.59 1.90 5.40 14.60 29.05

PCB 174 ppt 70 0.1 2105.0 0.69 2.65 8.55 23.05 60.50

PCB 175 ppt 70 0.0 171.1 0.00 0.30 1.05 3.20 6.36PCB 176 ppt 70 0.0 257.0 0.00 0.10 0.70 1.78 6.66

PCB 177 ppt 70 0.0 1303.0 1.09 2.90 6.70 27.65 64.14

PCB 178 ppt 70 0.0 1100.0 0.46 1.60 5.55 18.00 43.82

PCB 179 ppt 70 0.0 772.0 0.20 0.73 2.25 6.43 26.61

PCB 180 + PCB 193 ppt 70 0.0 8680.0 4.94 22.98 60.50 177.25 375.10

PCB 181 ppt 70 0.0 21.4 0.00 0.00 0.30 0.77 2.01

PCB 182 ppt 70 0.0 64.2 0.00 0.00 0.30 1.10 3.11

PCB 183 + PCB 185 ppt 70 0.0 2820.0 2.18 4.68 19.20 53.75 109.20

PCB 184 ppt 70 0.0 96.6 0.00 0.00 0.00 0.38 1.26

PCB 186 ppt 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 187 ppt 70 0.0 7990.0 4.25 16.25 47.50 118.25 307.50PCB 188 ppt 70 0.0 13.9 0.00 0.00 0.00 0.00 0.23

PCB 189 ppt 70 0.0 107.8 0.09 0.30 1.05 2.08 6.31
I-8

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

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B

s (continued)

Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 190 ppt 70 0.0 643.0 0.66 1.63 5.30 14.35 26.05

PCB 191 ppt 70 0.0 130.0 0.00 0.30 0.90 1.93 4.77

PCB 192 ppt 70 0.0 0.2 0.00 0.00 0.00 0.00 0.00

PCB 194 ppt 70 0.0 1683.0 0.80 3.85 11.90 37.53 87.23

PCB 195 ppt 70 0.0 610.0 0.00 0.75 4.45 12.83 25.45

PCB 196 ppt 70 0.0 1006.0 0.38 1.93 7.85 20.05 46.04

PCB 197 + PCB 200 ppt 70 0.0 177.1 0.00 0.33 1.25 3.15 7.65

PCB 198 + PCB 199 ppt 70 0.0 2206.0 1.47 5.35 18.50 51.00 113.90

PCB 201 ppt 70 0.0 263.0 0.00 0.00 0.95 6.65 17.53

PCB 202 ppt 70 0.0 490.0 0.10 1.35 4.20 12.75 30.74

PCB 203 ppt 70 0.0 1556.0 0.58 3.03 11.95 33.90 75.34

PCB 204 ppt 70 0.0 3.6 0.00 0.00 0.00 0.00 0.22

PCB 205 ppt 70 0.0 90.7 0.00 0.20 0.70 1.63 4.13PCB 206 ppt 70 0.0 530.0 0.09 2.08 10.45 20.15 57.10

PCB 207 ppt 70 0.0 100.0 0.10 0.40 1.80 4.28 11.17PCB 208 ppt 70 0.0 222.0 0.20 0.80 3.10 8.03 20.12PCB 209 ppt 70 0.0 609.0 0.09 0.88 4.15 10.80 30.80

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 1 ppt 52 0.0 32.6 0.00 0.00 0.00 0.00 0.20PCB 2 ppt 52 0.0 10.7 0.00 0.00 0.00 0.00 0.40

PCB 3 ppt 52 0.0 22.2 0.00 0.00 0.00 0.10 0.40

PCB 4 ppt 52 0.0 57.9 0.00 0.00 0.75 1.95 7.92

PCB 5 ppt 52 0.0 6.1 0.00 0.00 0.00 0.00 0.09
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-9

Ta

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Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 6 ppt 52 0.0 48.7 0.00 0.10 0.40 1.10 4.06

PCB 7 ppt 52 0.0 13.1 0.00 0.00 0.00 0.20 0.76PCB 8 ppt 52 0.0 321.0 0.00 0.45 1.60 5.85 12.97

PCB 9 ppt 52 0.0 19.1 0.00 0.00 0.00 0.23 1.00PCB 10 ppt 52 0.0 2.8 0.00 0.00 0.00 0.00 0.20PCB 11 ppt 52 0.0 310.0 0.00 0.00 0.85 2.60 5.49

PCB 12 + PCB 13 ppt 52 0.0 4.1 0.00 0.00 0.00 0.00 0.58

PCB 14 ppt 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

PCB 15 ppt 52 0.0 53.8 0.01 0.28 0.85 2.23 4.60

PCB 16 ppt 52 0.0 213.0 0.10 0.80 2.05 7.43 20.50PCB 17 ppt 52 0.0 469.0 0.21 0.95 2.70 10.48 43.75

PCB 18 + PCB 30 ppt 52 0.1 828.0 0.70 1.38 4.65 21.85 67.35PCB 19 ppt 52 0.0 47.8 0.01 0.20 0.60 1.80 5.46PCB 20 + PCB 28 ppt 52 0.0 4470.0 3.00 9.08 37.50 122.50 275.20

PCB 21 + PCB 33 ppt 52 0.0 1169.0 0.71 1.80 4.80 13.20 48.05

PCB 22 ppt 52 0.0 1085.0 0.42 1.85 6.10 17.60 53.98

PCB 23 ppt 52 0.0 4.5 0.00 0.00 0.00 0.00 0.00

PCB 24 ppt 52 0.0 13.7 0.00 0.00 0.00 0.23 1.69PCB 25 ppt 52 0.0 188.0 0.00 0.28 1.25 2.63 12.00

PCB 26 + PCB 29 ppt 52 0.0 533.0 0.00 0.60 2.75 5.45 28.80

PCB 27 ppt 52 0.0 59.6 0.00 0.07 0.35 1.88 7.28

PCB 31 ppt 52 0.0 2960.0 1.08 5.38 17.15 42.95 125.20

PCB 32 ppt 52 0.0 282.0 0.20 0.40 1.15 4.83 29.38

PCB 34 ppt 52 0.0 14.8 0.00 0.00 0.10 0.63 1.89

PCB 35 ppt 52 0.0 0.5 0.00 0.00 0.00 0.00 0.00
I-10

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

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B

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Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 36 ppt 52 0.0 0.3 0.00 0.00 0.00 0.00 0.00

PCB 37 ppt 52 0.0 188.0 0.10 0.68 1.65 6.10 15.53

PCB 38 ppt 52 0.0 4.7 0.00 0.00 0.00 0.00 0.20PCB 39 ppt 52 0.0 27.7 0.00 0.00 0.00 0.55 1.81

PCB 40 + PCB 41 + PCB 71 ppt 52 0.0 1666.0 0.63 3.50 11.45 30.73 130.91

PCB 42 ppt 52 0.0 1298.0 0.51 2.40 11.75 30.00 103.20

PCB 43 ppt 52 0.0 166.7 0.00 0.07 1.40 3.98 11.50PCB 44 + PCB 47 + PCB 65 ppt 52 0.7 4250.0 4.15 13.58 57.50 131.50 452.50

PCB 45 + PCB 51 ppt 52 0.0 426.0 0.01 0.48 2.45 7.48 32.64

PCB 46 ppt 52 0.0 65.6 0.00 0.00 0.45 1.63 7.04

PCB 48 ppt 52 0.0 1054.0 0.41 1.35 5.75 20.98 63.88PCB 49 + PCB 69 ppt 52 0.0 3340.0 2.80 8.30 38.95 131.58 393.80

PCB 50 + PCB 53 ppt 52 0.0 279.0 0.00 0.00 1.25 6.65 30.50

PCB 52 ppt 52 0.2 4080.0 1.94 12.55 62.50 144.25 705.20

PCB 54 ppt 52 0.0 3.0 0.00 0.00 0.00 0.00 0.29PCB 55 ppt 52 0.0 51.0 0.00 0.00 0.00 0.60 3.78

PCB 56 ppt 52 0.1 1428.0 1.66 4.30 14.00 30.38 117.82PCB 57 ppt 52 0.0 36.9 0.00 0.00 0.30 0.90 2.40PCB 58 ppt 52 0.0 32.2 0.00 0.00 0.30 1.08 2.85

PCB 59 + PCB 62 + PCB 75 ppt 52 0.0 418.0 0.20 1.20 5.50 16.50 43.67

PCB 60 ppt 52 0.1 1275.0 1.62 3.98 9.95 29.35 99.14

PCB 61 + PCB 70 + PCB 74 + PCB 76 ppt 52 0.3 9140.0 7.22 24.28 92.50 360.25 867.60

PCB 63 ppt 52 0.0 301.5 0.40 1.05 3.75 13.75 42.20
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-11

Ta

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Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 64 ppt 52 0.4 2266.0 1.13 6.68 23.05 63.30 199.10

PCB 66 ppt 52 0.5 5690.0 4.30 24.45 55.00 285.50 921.10

PCB 67 ppt 52 0.0 150.3 0.00 0.30 1.25 2.70 11.59

PCB 68 ppt 52 0.0 64.0 0.20 0.50 1.20 5.08 17.17

PCB 72 ppt 52 0.0 58.0 0.00 0.30 1.45 3.50 12.68

PCB 73 ppt 52 0.0 5.3 0.00 0.00 0.00 0.00 0.00

PCB 77 ppt 52 0.0 125.0 0.00 0.17 2.90 8.15 18.13PCB 78 ppt 52 0.0 4.8 0.00 0.00 0.00 0.00 0.00

PCB 79 ppt 52 0.0 55.0 0.01 0.63 2.20 5.33 22.56PCB 80 ppt 52 0.0 4.2 0.00 0.00 0.00 0.00 0.00

PCB 81 ppt 52 0.0 15.3 0.00 0.00 0.40 1.25 2.59

PCB 82 ppt 52 0.0 237.0 0.53 2.70 7.50 24.20 44.30

PCB 83 + PCB 99 ppt 52 1.3 7200.0 15.35 45.55 110.00 513.75 1721.00

PCB 84 ppt 52 0.0 311.0 1.06 4.08 10.80 28.83 101.31

PCB 85 + PCB 116 + PCB 117 ppt 52 0.4 711.0 4.10 9.38 28.00 125.00 481.90PCB 86 + PCB 87 + PCB 97 + PCB 108 + PCB 119 + PCB 125 ppt 52 0.3 2000.0 6.16 23.15 103.00 289.50 1272.00

PCB 88 + PCB 91 ppt 52 0.1 600.0 1.41 3.23 15.90 39.33 230.60

PCB 89 ppt 52 0.0 32.4 0.00 0.00 0.20 1.43 4.84

PCB 90 + PCB 101 + PCB 113 ppt 52 1.5 5200.0 14.08 46.15 134.50 492.50 1619.00

PCB 92 ppt 52 0.6 1170.0 3.20 8.08 16.75 80.50 338.40

PCB 93 + PCB 95 + PCB 98 + PCB 100 + PCB 102 ppt 52 0.3 1420.0 4.96 16.60 60.35 182.68 413.80

PCB 94 ppt 52 0.0 13.1 0.00 0.00 0.25 0.83 3.28
I-12

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Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

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Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 96 ppt 52 0.0 16.2 0.00 0.00 0.00 0.25 1.97PCB 103 ppt 52 0.0 100.0 0.10 0.30 1.00 3.68 13.75

PCB 104 ppt 52 0.0 1.5 0.00 0.00 0.00 0.00 0.00

PCB 105 ppt 52 0.0 1399.0 5.15 18.90 58.00 151.08 683.80PCB 106 ppt 52 0.0 1.6 0.00 0.00 0.00 0.00 0.00

PCB 107 + PCB 124 ppt 52 0.0 130.0 0.72 1.88 4.90 12.85 31.84

PCB 109 ppt 52 0.1 630.0 1.22 5.90 15.15 53.13 213.50

PCB 110 + PCB 115 ppt 52 0.8 3500.0 19.10 34.63 123.00 349.00 1497.00

PCB 111 ppt 52 0.0 21.8 0.00 0.18 0.40 1.60 3.54

PCB 112 ppt 52 0.0 2.4 0.00 0.00 0.00 0.00 0.00

PCB 114 ppt 52 0.0 98.8 0.53 1.18 3.30 11.90 53.11

PCB 118 ppt 52 0.0 5870.0 20.75 47.40 147.50 605.00 1747.70PCB 120 ppt 52 0.0 236.0 0.21 0.40 1.05 4.90 21.35

PCB 121 ppt 52 0.0 13.7 0.00 0.00 0.20 0.80 1.49PCB 122 ppt 52 0.0 39.6 0.20 0.50 1.35 4.18 13.03

PCB 123 ppt 52 0.0 90.6 0.41 0.98 3.45 11.23 34.57

PCB 126 ppt 52 0.0 25.3 0.00 0.00 0.00 1.80 6.58

PCB 127 ppt 52 0.0 8.2 0.00 0.00 0.30 1.33 4.06

PCB 128 + PCB 166 ppt 52 0.6 2220.0 7.34 15.95 70.00 127.50 478.40

PCB 129 + PCB 138 + PCB 160 + PCB 163 ppt 52 4.0 25200.0 45.60 138.25 327.00 882.25 3459.00

PCB 130 ppt 52 0.1 1280.0 1.55 4.83 25.75 57.20 210.60

PCB 131 ppt 52 0.0 49.0 0.01 0.48 2.30 5.70 14.02

PCB 132 ppt 52 0.0 1080.0 4.04 8.40 50.00 122.25 310.60PCB 133 ppt 52 0.0 620.0 0.60 2.78 6.80 18.38 74.37
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-13

Ta

b

le I-2. PC

B

s (continued)

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 134 + PCB 143 ppt 52 0.0 186.0 0.42 1.58 9.30 16.65 49.40PCB 135 + PCB 151 + PCB 154 ppt 52 1.2 3600.0 7.64 19.23 66.00 154.00 614.20

PCB 136 ppt 52 0.0 247.0 0.90 2.83 8.90 19.73 80.68

PCB 137 ppt 52 0.0 530.0 1.30 4.75 14.25 47.78 152.20

PCB 139 + PCB 140 ppt 52 0.0 286.0 0.51 1.70 5.50 22.78 55.90

PCB 141 ppt 52 0.7 2450.0 1.91 12.83 38.30 108.75 349.90

PCB 142 ppt 52 0.0 2.0 0.00 0.00 0.00 0.00 0.00

PCB 144 ppt 52 0.0 263.0 0.31 1.98 5.70 18.30 55.24

PCB 145 ppt 52 0.0 2.0 0.00 0.00 0.00 0.00 0.29

PCB 146 ppt 52 1.6 8400.0 6.68 20.75 58.00 227.00 749.10

PCB 147 + PCB 149 ppt 52 4.2 11500.0 21.00 36.20 182.00 389.25 1367.00PCB 148 ppt 52 0.0 98.1 0.00 0.10 0.65 1.73 7.26

PCB 150 ppt 52 0.0 30.0 0.00 0.00 0.30 0.93 2.54PCB 152 ppt 52 0.0 2.0 0.00 0.00 0.00 0.23 0.89

PCB 153 + PCB 168 ppt 52 4.0 56000.0 22.90 151.75 435.00 1500.00 5400.00

PCB 155 ppt 52 0.0 118.2 0.00 0.00 0.10 0.43 10.95PCB 156 + PCB 157 ppt 52 0.1 1300.0 2.01 9.75 31.10 80.50 342.30

PCB 158 ppt 52 0.3 1850.0 2.24 7.85 37.00 82.50 319.20PCB 159 ppt 52 0.0 118.0 0.31 0.85 2.45 7.05 19.69PCB 161 ppt 52 0.0 2.0 0.00 0.00 0.00 0.00 0.00

PCB 162 ppt 52 0.0 135.0 0.30 0.95 2.10 7.30 16.20

PCB 164 ppt 52 0.0 740.0 1.21 4.18 11.80 41.28 155.90

PCB 165 ppt 52 0.0 22.1 0.00 0.00 0.25 0.80 2.66

PCB 167 ppt 52 0.0 1170.0 1.14 4.08 17.90 40.28 163.90
I-14

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-2. PC

B

s (continued)

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 169 ppt 52 0.0 2.7 0.00 0.00 0.20 0.60 0.79

PCB 170 ppt 52 0.2 9100.0 3.92 26.25 78.20 230.50 771.30

PCB 171 + PCB 173 ppt 52 0.1 3820.0 1.02 5.08 24.65 85.25 225.25

PCB 172 ppt 52 0.1 3880.0 1.12 5.93 19.65 62.25 151.37

PCB 174 ppt 52 0.5 3640.0 6.24 14.70 47.40 99.43 449.00

PCB 175 ppt 52 0.0 431.0 0.21 1.33 4.10 9.93 32.74

PCB 176 ppt 52 0.1 470.0 0.61 1.18 3.00 12.38 38.71

PCB 177 ppt 52 0.0 5200.0 2.47 10.28 53.20 118.13 450.60PCB 178 ppt 52 0.5 1780.0 2.04 6.33 17.55 45.48 208.90

PCB 179 ppt 52 0.1 907.0 2.03 5.33 14.75 42.50 165.60PCB 180 + PCB 193 ppt 52 0.1 47100.0 14.54 72.00 229.50 647.50 1981.40

PCB 181 ppt 52 0.0 69.0 0.00 0.30 1.10 2.85 8.77

PCB 182 ppt 52 0.0 153.0 0.10 0.48 1.95 4.93 8.15PCB 183 + PCB 185 ppt 52 0.8 10600.0 5.19 20.80 69.35 145.83 621.50

PCB 184 ppt 52 0.0 63.0 0.00 0.10 0.45 1.20 4.08PCB 186 ppt 52 0.0 2.8 0.00 0.00 0.00 0.00 0.00

PCB 187 ppt 52 0.0 15400.0 7.43 45.48 176.50 309.25 1459.90

PCB 188 ppt 52 0.0 57.0 0.00 0.00 0.00 1.18 4.24

PCB 189 ppt 52 0.0 493.0 0.31 1.18 3.60 8.85 26.95

PCB 190 ppt 52 0.0 3060.0 0.76 5.03 15.15 55.25 180.66

PCB 191 ppt 52 0.0 699.0 0.10 0.98 3.20 10.23 27.34

PCB 192 ppt 52 0.0 1.2 0.00 0.00 0.00 0.00 0.09

PCB 194 ppt 52 1.5 8470.0 4.12 10.75 33.40 131.55 348.80

PCB 195 ppt 52 0.0 2770.0 0.52 3.48 13.15 47.00 123.20PCB 196 ppt 52 0.4 4860.0 1.64 6.08 17.70 75.08 177.80
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-15

Ta

b

le I-2. PC

B

s (continued)

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

PCB 197 + PCB 200 ppt 52 0.0 560.0 0.72 1.65 5.60 15.15 30.34

PCB 198 + PCB 199 ppt 52 0.4 8000.0 5.48 27.68 67.50 202.00 446.50

PCB 201 ppt 52 0.0 570.0 0.21 1.92 7.38 17.75 53.52

PCB 202 ppt 52 0.3 936.0 1.84 7.08 16.40 36.25 93.67PCB 203 ppt 52 0.0 6280.0 1.43 9.05 45.00 116.08 314.30

PCB 204 ppt 52 0.0 5.5 0.00 0.00 0.00 0.33 1.32PCB 205 ppt 52 0.0 353.0 0.30 0.70 2.60 7.45 21.60

PCB 206 ppt 52 1.2 1430.0 4.49 7.13 47.95 132.03 292.00

PCB 207 ppt 52 0.2 253.0 0.71 1.75 5.85 22.25 56.70

PCB 208 ppt 52 0.0 660.0 1.50 4.38 20.00 54.55 120.18

PCB 209 ppt 52 0.0 839.0 1.02 3.90 20.85 65.25 216.89
I-16

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-3.

Dioxins and Furans

Tissue Concentration Differences for Predators (Fillets)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

2,3,7,8-TCDD ppt 70 0.0 0.5 0.00 0.00 0.00 0.02 0.04

1,2,3,7,8-PeCDD ppt 70 0.0 0.3 0.00 0.00 0.00 0.00 0.04

1,2,3,4,7,8-HxCDD ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.00

1,2,3,6,7,8-HxCDD ppt 70 0.0 0.5 0.00 0.00 0.00 0.01 0.03

1,2,3,7,8,9-HxCDD ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.02

1,2,3,4,6,7,8-HpCDD ppt 70 0.0 0.6 0.00 0.00 0.00 0.00 0.04

OCDD ppt 70 0.0 1.8 0.00 0.00 0.00 0.00 0.00

2,3,7,8-TCDF ppt 70 0.0 1.3 0.00 0.00 0.01 0.03 0.10

1,2,3,7,8-PeCDF ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.01

2,3,4,7,8-PeCDF ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.02

1,2,3,4,7,8-HxCDF ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.00

1,2,3,6,7,8-HxCDF ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.00

1,2,3,7,8,9-HxCDF ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.00

2,3,4,6,7,8-HxCDF ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.00

1,2,3,4,6,7,8-HpCDF ppt 70 0.0 0.2 0.00 0.00 0.00 0.00 0.00

1,2,3,4,7,8,9-HpCDF ppt 70 0.0 0.1 0.00 0.00 0.00 0.00 0.00

OCDF ppt 70 0.0 0.3 0.00 0.00 0.00 0.00 0.00

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

2,3,7,8-TCDD ppt 52 0.0 1.3 0.00 0.00 0.02 0.10 0.201,2,3,7,8-PeCDD ppt 52 0.0 0.8 0.00 0.00 0.04 0.10 0.201,2,3,4,7,8-HxCDD ppt 52 0.0 0.3 0.00 0.00 0.01 0.10 0.141,2,3,6,7,8-HxCDD ppt 52 0.0 1.3 0.00 0.00 0.08 0.20 0.50

1,2,3,7,8,9-HxCDD ppt 52 0.0 0.3 0.00 0.00 0.00 0.06 0.10
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-17

Ta

b

le I-3.

Dioxins and Furans (continued)

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

1,2,3,4,6,7,8-HpCDD ppt 52 0.0 3.5 0.00 0.00 0.14 0.38 0.90

OCDD ppt 52 0.0 31.5 0.00 0.00 0.00 1.55 7.35

2,3,7,8-TCDF ppt 52 0.0 2.3 0.00 0.00 0.04 0.11 0.34

1,2,3,7,8-PeCDF ppt 52 0.0 0.1 0.00 0.00 0.00 0.01 0.04

2,3,4,7,8-PeCDF ppt 52 0.0 0.6 0.00 0.00 0.01 0.10 0.191,2,3,4,7,8-HxCDF ppt 52 0.0 0.1 0.00 0.00 0.00 0.01 0.03

1,2,3,6,7,8-HxCDF ppt 52 0.0 0.1 0.00 0.00 0.00 0.01 0.03

1,2,3,7,8,9-HxCDF ppt 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

2,3,4,6,7,8-HxCDF ppt 52 0.0 0.1 0.00 0.00 0.00 0.00 0.03

1,2,3,4,6,7,8-HpCDF ppt 52 0.0 0.3 0.00 0.00 0.00 0.01 0.05

1,2,3,4,7,8,9-HpCDF ppt 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

OCDF ppt 52 0.0 0.1 0.00 0.00 0.00 0.00 0.00
I-18

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-4. Or

gan

o

c

h

l

orine Pesticid

e

s

Tissue Concentration Differences for Predators (Fillets)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Total DDT

2,4'-DDD ppb 57 0.0 0.0 0.00 0.00 0.00 0.00 0.00

2,4'-DDE ppb 57 0.0 4.1 0.00 0.00 0.00 0.00 0.00

2,4'-DDT ppb 57 0.0 4.5 0.00 0.00 0.00 0.00 0.00

4,4'-DDD ppb 70 0.0 1.8 0.00 0.00 0.00 0.00 0.00

4,4'-DDE ppb 70 0.0 17.0 0.00 0.05 0.54 1.68 4.96

4,4'-DDT ppb 70 0.0 17.9 0.00 0.00 0.00 0.00 1.16

Total Chlordane

Chlordane, alpha- ppb 70 0.0 6.5 0.00 0.00 0.00 0.00 0.00

Chlordane, gamma- ppb 70 0.0 0.3 0.00 0.00 0.00 0.00 0.00

Nonachlor, cis- ppb 70 0.0 8.9 0.00 0.00 0.00 0.00 0.00

Nonachlor, trans- ppb 70 0.0 21.2 0.00 0.00 0.00 0.00 0.00

Oxychlordane ppb 70 0.0 2.1 0.00 0.00 0.00 0.00 0.00

Other 

Organochlorine Pesticides

Aldrin ppb 70 0.0 1.0 0.00 0.00 0.00 0.00 0.00

Dicofol ppb 70 0.0 48.6 0.00 0.00 0.00 0.00 0.00

Dieldrin ppb 70 0.0 5.8 0.00 0.00 0.00 0.00 0.00

Endosulfan I ppb 70 0.0 2.0 0.00 0.00 0.00 0.00 0.00

Endosulfan II ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Endosulfan Sulfate ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Endrin ppb 70 0.0 2.1 0.00 0.00 0.00 0.00 0.00

Ethalfluralin ppb 70 0.0 1.3 0.00 0.00 0.00 0.00 0.00

Heptachlor ppb 70 0.0 4.8 0.00 0.00 0.00 0.00 0.00

Heptachlor epoxide ppb 70 0.0 2.2 0.00 0.00 0.00 0.00 0.00
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-19

Ta

b

le I-4. Or

gan

o

c

h

l

orine Pesticid

e

s (continued)

Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Hexachlorocyclohexane (BHC), alpha- ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Hexachlorocyclohexane (BHC), beta- ppb 70 0.0 5.7 0.00 0.00 0.00 0.00 0.84

Hexachlorocyclohexane (BHC), delta- ppb 70 0.0 1.0 0.00 0.00 0.00 0.00 0.00

Isodrin ppb 70 0.0 1.4 0.00 0.00 0.00 0.00 0.00

Kepone (Chlordecone) ppb 70 0.0 130.8 0.00 0.00 0.00 0.00 7.69

Methoxychlor ppb 70 0.0 5.5 0.00 0.00 0.00 0.00 0.00

Mirex ppb 70 0.0 0.7 0.00 0.00 0.00 0.00 0.00

Octachlorostyrene ppb 70 0.0 0.4 0.00 0.00 0.00 0.00 0.00

Pendimethalin ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Pentachloroanisole ppb 70 0.0 2.5 0.00 0.00 0.00 0.03 0.42

Pentachloronitrobenzene ppb 70 0.0 1.9 0.00 0.00 0.00 0.00 0.04

Permethrin, cis- ppb 70 0.0 41.6 0.00 0.00 0.00 0.00 0.00

Permethrin, trans- ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Toxaphene ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Trifluralin ppb 70 0.0 8.3 0.00 0.00 0.00 0.00 0.01

Tissue Concentration Differences for 

Bottom Dwellers (Whole bodies)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Total DDT

2,4'-DDD ppb 39 0.0 1.5 0.00 0.00 0.00 0.00 0.00

2,4'-DDE ppb 39 0.0 6.3 0.00 0.00 0.00 0.49 1.37

2,4'-DDT ppb 39 0.0 10.1 0.00 0.00 0.00 0.00 0.06

4,4'-DDD ppb 52 0.0 61.0 0.00 0.00 0.00 1.26 4.01
I-20

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-4. Or

g

an

o

c

h

l

o

rin e P

e

sticid

e

s (continued)

Tissue Concentration Differences for 

B

ottom Dwellers (Whole bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

4,4'-DDE ppb 52 0.0 641.6 0.21 0.54 2.58 6.50 20.27

4,4'-DDT ppb 52 0.0 29.4 0.00 0.00 0.00 0.48 3.78

Total Chlordane

Chlordane, alpha- ppb 52 0.0 4.3 0.00 0.00 0.00 0.43 1.90

Chlordane, gamma- ppb 52 0.0 5.1 0.00 0.00 0.00 0.00 0.11

Nonachlor, cis- ppb 52 0.0 39.3 0.00 0.00 0.00 0.09 5.94

Nonachlor, trans- ppb 52 0.0 10.6 0.00 0.00 0.00 0.63 1.52

Oxychlordane ppb 52 0.0 3.7 0.00 0.00 0.00 0.00 0.26

Other 

Organochlorine Pesticides

Aldrin ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Dicofol ppb 52 0.0 586.8 0.00 0.00 0.00 0.00 0.00

Dieldrin ppb 52 0.0 15.4 0.00 0.00 0.00 0.09 1.41

Endosulfan I ppb 52 0.0 5.4 0.00 0.00 0.00 0.00 0.00

Endosulfan II ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Endosulfan Sulfate ppb 52 0.0 2.1 0.00 0.00 0.00 0.00 0.00

Endrin ppb 52 0.0 7.3 0.00 0.00 0.00 0.00 0.00

Ethalfluralin ppb 52 0.0 11.7 0.00 0.00 0.00 0.61 2.45

Heptachlor ppb 52 0.0 16.3 0.00 0.00 0.00 0.00 0.67

Heptachlor epoxide ppb 52 0.0 3.8 0.00 0.00 0.00 0.00 0.02

Hexachlorocyclohexane (BHC), alpha- ppb 52 0.0 0.7 0.00 0.00 0.00 0.00 0.00

Hexachlorocyclohexane (BHC), beta- ppb 52 0.0 10.6 0.00 0.00 0.00 0.00 2.81

Hexachlorocyclohexane (BHC), delta- ppb 52 0.0 2.6 0.00 0.00 0.00 0.00 0.00
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-21

Ta

b

le I-4. Or

gan

o

c

h

l

orine Pesticid

e

s (continued)

Tissue Concentration Differences for 

Bottom Dwellers (Whole bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Isodrin ppb 52 0.0 2.4 0.00 0.00 0.00 0.00 0.00

Kepone (Chlordecone) ppb 52 0.0 174.0 0.00 0.00 0.00 2.20 21.97

Methoxychlor ppb 52 0.0 48.9 0.00 0.00 0.00 0.00 0.00

Mirex ppb 52 0.0 1.2 0.00 0.00 0.00 0.00 0.00

Octachlorostyrene ppb 52 0.0 1.1 0.00 0.00 0.00 0.00 0.00

Pendimethalin ppb 52 0.0 17.3 0.00 0.00 0.00 0.00 1.30

Pentachloroanisole ppb 52 0.0 2.7 0.00 0.00 0.00 0.07 0.46

Pentachloronitrobenzene ppb 52 0.0 2.9 0.00 0.00 0.00 0.00 0.34

Permethrin, cis- ppb 52 0.0 124.0 0.00 0.00 0.00 0.00 0.00

Permethrin, trans- ppb 52 0.0 32.4 0.00 0.00 0.00 0.00 0.00

Toxaphene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Trifluralin ppb 52 0.0 66.9 0.00 0.00 0.00 1.07 7.46
I-22

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-5. Semivolatile Or

ganic Comp

ounds

Tissue Concentration Differences for Predators (Fillets)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Semivolatile 

Organic Compounds: PA

Hs

Acenaphthene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Anthracene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Benzo[a]Anthracene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Benzo[a]Pyrene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Benzo(b)Fluoranthene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Benzo(ghi)Perylene ppb 70 0.0 1776.0 0.00 0.00 0.00 0.00 0.00

Benzo(j)Fluoranthene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Benzo(k)Fluoranthene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Chrysene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Dibenz[a,h]Anthrancene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Fluoranthene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Fluorene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Indeno(1,2,3-cd)Pyrene ppb 70 0.0 1776.0 0.00 0.00 0.00 0.00 0.00

Naphthalene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Perylene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Phenanthrene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Pyrene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Other Semivolatile 

Organic Compounds

1,2,4,5-Tetrachlorobenzene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

1,2,4-Trichlorobenzene (TCB) ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

1,2-Dichlorobenzene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

1,3-Dichlorobenzene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

1,4-Dichlorobenzene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-23

Ta

b

le I-5. Semivolatile Or

ganic Comp

ounds (continued)

Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

2,4,5-Trichlorophenol ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

2,4,6-Tris(1,1-Dimethylethyl)Phenol ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

4,4'-Methylenebis(2-Chloroaniline) ppb 70 0.0 1776.0 0.00 0.00 0.00 0.00 0.00

4-Bromophenyl Phenyl Ether ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

4-Nonylphenol ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Acenaphthylene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Bis(2-ethylhexyl)phthalate ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Butyl benzyl phthalate ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Chlorpyriphos ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Diazinon ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Diethylstilbestrol ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Disulfoton ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Disulfoton Sulfone ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Ethion ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Hexachlorocyclohexane, gamma-BHC (Lindane) ppb 70 0.0 1.1 0.00 0.00 0.00 0.00 0.00

Hexachlorobenzene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Hexachlorobutadiene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Nitrobenzene ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Paraoxon ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Parathion-Ethyl ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Pentachlorobenzene ppb 70 0.0 1776.0 0.00 0.00 0.00 0.00 0.00

Pentachlorophenol ppb 70 0.0 4440.0 0.00 0.00 0.00 0.00 0.00
I-24

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-5. Semivolatile Or

ganic Comp

ounds (continued)

Tissue Concentration Differences for Predators (Fillets) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Phenol ppb 70 0.0 888.0 0.00 0.00 0.00 0.00 0.00

Terbufos ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Terbufos Sulfone ppb 70 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Tetrabromobisphenol A ppb 70 0.0 44400.0 0.00 0.00 0.00 0.00 0.00

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Semivolatile 

Organic Compounds: PA

Hs

Acenaphthene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Anthracene ppb 52 0.0 999.0 0.00 0.00 0.00 0.00 0.00

Benzo[a]Anthracene ppb 52 0.0 999.0 0.00 0.00 0.00 0.00 0.00

Benzo[a]Pyrene ppb 52 0.0 999.0 0.00 0.00 0.00 0.00 0.00

Benzo(b)Fluoranthene ppb 52 0.0 999.0 0.00 0.00 0.00 0.00 0.00

Benzo(ghi)Perylene ppb 52 0.0 1998.0 0.00 0.00 0.00 0.00 0.00

Benzo(j)Fluoranthene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Benzo(k)Fluoranthene ppb 52 0.0 999.0 0.00 0.00 0.00 0.00 0.00

Chrysene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Dibenz[a,h]Anthrancene ppb 52 0.0 999.0 0.00 0.00 0.00 0.00 0.00

Fluoranthene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Fluorene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Indeno(1,2,3-cd)Pyrene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Naphthalene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Perylene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Phenanthrene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Pyrene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00
The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

I-25

Ta

b

le I-5. Semivolatile Or

ganic Comp

ounds (continued)

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Other Semivolatile 

Organic Compounds

1,2,4,5-Tetrachlorobenzene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

1,2,4-Trichlorobenzene (TCB) ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

1,2-Dichlorobenzene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

1,3-Dichlorobenzene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

1,4-Dichlorobenzene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

2,4,5-Trichlorophenol ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

2,4,6-Tris(1,1-Dimethylethyl)Phenol ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

4,4'-Methylenebis(2-Chloroaniline) ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

4-Bromophenyl Phenyl Ether ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

4-Nonylphenol ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Acenaphthylene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Bis(2-ethylhexyl)phthalate ppb 52 0.0 19780.1 0.00 0.00 0.00 0.00 0.00

Butyl benzyl phthalate ppb 52 0.0 999.0 0.00 0.00 0.00 0.00 0.00

Chlorpyriphos ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Diazinon ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Diethylstilbestrol ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Disulfoton ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Disulfoton Sulfone ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Ethion ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Hexachlorocyclohexane, gamma-BHC (Lindane) ppb 52 0.0 1.5 0.00 0.00 0.00 0.00 0.34
I-26

The National Study of Chemical Residues in Lake Fish Tissue

Appendix I: Tissue Concentration Differences between Replicate Sample Pairs

Ta

b

le I-5. Semivolatile Or

ganic Comp

ounds (continued)

Tissue Concentration Differences for 

Bottom Dwellers (Whole 

Bodies) (continued)

Chemical Units

Number of 

Samples

Minimum 

Difference

Maximum 

Difference

10th

Percentile

25th

Percentile Median

75th

Percentile

90th

Percentile

Hexachlorobenzene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Hexachlorobutadiene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Nitrobenzene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Paraoxon ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Parathion-Ethyl ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Pentachlorobenzene ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Pentachlorophenol ppb 52 0.0 4995.0 0.00 0.00 0.00 0.00 0.00

Phenol ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Terbufos ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Terbufos Sulfone ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00

Tetrabromobisphenol A ppb 52 0.0 0.0 0.00 0.00 0.00 0.00 0.00