&EPA
United States
Environmental Protection
Agency
Office of Water
(4305)
EPA-823-R-99-014
September 1999
The National Survey of
Mercury Concentrations
in Fish
Data Base Summary
1990-1995
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THE NATIONAL SURVEY OF
MERCURY CONCENTRATIONS IN FISH
DATA BASE SUMMARY
1990 -1995
September 10, 1999
U.S. Environmental Protection Agency
Standards and Applied Science Division
401 M Street, SW
Washington, DC 20460
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DISCLAIMER
The U.S. Environmental Protection Agency (EPA) through the Standards and Applied Science
Division funded and managed the preparation of this document under Contract No. 68-C4-0051 to
The Cadmus Group, Inc. The mention of trade names or commercial products does not constitute
endorsement or recommendation for use by either EPA or Cadmus of the product or the
manufacturer.
11
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ACKNOWLEDGMENTS
This work was completed by the U.S. Environmental Protection Agency (EPA) with technical
support from The Cadmus Group, Inc., under Contract No. 68-C4-0051. Mr. Rick Hoffmann served
as the Work Assignment Manager for the draft report, and Mr. James Keating served as Work
Assignment Manager for the final report. We wish to thank all of the state water quality offices and
numerous professionals from other organizations for the responses received to requests for
information. We also express gratitude to the numerous personnel from EPA and Cadmus who have
participated in this project.
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IV
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TABLE OF CONTENTS
Page
1. INTRODUCTION AND BACKGROUND 1-1
1.1 DISCUSSION OF THE ISSUE 1-1
1.1.1 Mercury Speciation and Cycling in the Aquatic Ecosystem 1-1
1.1.2 Methylmercury 1-2
1.1.3 Methylmercury in the Aquatic Ecosystem 1-2
1.1.4 The Toxic Effects of Methylmercury 1-3
1.2 PURPOSE OF DATA COMPILATION 1-4
1.3 THIS DOCUMENT 1-5
2. DATA BASE STRUCTURE AND FORMAT 2-1
2.1 OVERVIEW OF THE DATA BASE 2-1
2.2 DATABASE FORMAT 2-1
2.3 INCONSISTENCIES AMONG DATA SETS 2-1
2.3.1 Missing Data or Blank Fields 2-4
2.3.2 Differing Data Structures 2-4
2.3.3 Differing Coding Systems 2-4
2.4 STANDARDIZATION OF VARIABLES 2-5
2.5 GENERAL QUALITY ASSURANCE/QUALITY CONTROL 2-7
3. NATIONAL AND STATE OVERVIEW 3-1
3.1 NATIONAL OVERVIEW 3-1
3.1.1 Availability of Data Variables 3-1
3.1.2 Type of Sampling and Analysis 3-3
3.1.3 Extent of Sampling 3-3
3.1.4 Mercury Concentrations in Selected Fish Species 3-6
3.2 STATE PROFILES 3-8
4. ANALYSIS AN D ANALYSIS ISSUES 4-1
4.1 VARIABILITY IN THE DATA BASE 4-1
4.2 TREATMENT OF NON DETECTS 4-1
4.3 MERCURY CONTENT IN DIFFERENT CATEGORIES OF FISH 4-4
4.4 ADDITIONAL DATA 4-7
4.4.1 Environmental Parameters 4-7
4.4.2 Fish Parameters 4-9
4.5 PREDICTIVE STATISTICAL ANALYSES 4-9
4.6 POTENTIAL FUTURE USES OF THE DATA BASE 4-11
5. REFERENCES 5-1
APPENDIX: Request for Mercury Concentrations in Fish Tissue Data
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LIST OF TABLES
Page
2-1 The National Survey of Mercury Concentrations in Fish: DataBase Sources 2-2
2-2 The National Survey of Mercury Concentrations in Fish: Data Base Field
Descriptors 2-3
2-3 Standardized Portion Codes 2-5
2-4 Examples of Qualifiers for Mercury Concentrations 2-6
3-1 The National Survey of Mercury Concentrations in Fish: Presence/Absence of
Variables in Data Base 3-2
3-2 The National Survey of Mercury Concentrations in Fish: Presence/Absence of
Fish and Mercury Information in Data Base 3-4
3-3 The National Survey of Mercury Concentrations in Fish: Number of Records
and Years in Data Base 3-5
3-4 The National Survey of Mercury Concentrations in Fish: Mean Mercury
Concentrations (ppm) in Major Fish Species 3-7
3-5 Range of Mean Mercury Concentrations (ppm) for Major Fish Species 3-8
4-1 Effects of Non-detected Observations on Mercury Concentrations in Fish 4-3
4-2 Weighted Mean and Mercury Concentration by Percentile for Different
Categories of Fish 4-6
VI
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LIST OF FIGURES
Page
1-1 Mercury Cycling in Surface Water 1-1
3-1 Sampling Locations with Latitude and Longitude 3-1
3-2 Concentration Ranges of Mercury in Tissues of Selected Fish Species 3-6
4-1 Cumulative Distribution of Mercury Concentrations in Resident & Migratory
Fish 4-5
4-2 Cumulative Distribution of Mercury Concentrations in Edible and Inedible
Fish 4-5
4-3 Cumulative Distribution of Mercury Concentrations in Demersal and Pelagic
Fish 4-6
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SECTION 1
INTRODUCTION AND BACKGROUND
1.1 DISCUSSION OF THE ISSUE
Mercury cycles in the environment as a result of natural and anthropogenic activities. The amount
of mercury mobilized and released into the biosphere has increased since the beginning of the
industrial age. Most of the mercury in the atmosphere is elemental mercury vapor, which circulates
in the atmosphere for up to a year, and hence can be widely dispersed and transported thousands of
miles from likely sources of emissions. Most of the mercury in water, soil, sediments, or plants and
animals is in the form of inorganic mercury salts and organic forms of mercury (e.g.,
methylmercury). The inorganic form of mercury, when either bound to airborne particles or in a
gaseous form, is readily removed from the atmosphere by precipitation and is also dry deposited.
Wet deposition is the primary mechanism for transporting mercury from the atmosphere to surface
waters and land. Even after it deposits, mercury commonly is emitted back to the atmosphere either
as a gas or associated with particles, to be re-deposited elsewhere. As it cycles between the
atmosphere, land, and water, mercury undergoes a series of complex chemical and physical
transformations, many of which are not completely understood.
Mercury accumulates most efficiently in the aquatic food web. Predatory organisms at the top of the
food web generally have higher mercury concentrations. Numerous studies in lotic and lentic
freshwater environments have shown that the vast majority of total mercury in fish tissue is
methylmercury, with nearly all total mercury as methylmercury in upper trophic level fish. Inorganic
mercury, which is less efficiently absorbed and more readily eliminated from the body than
methylmercury, does not tend to bioaccumulate. Fish consumption dominates the pathway for
human and wildlife exposure to methylmercury.
1-1. Cycling in
Air
HgO
1.1.1 Mercury Speciation and Cycling in the Aquatic Ecosystem
Understanding the distribution and
cycling of mercury among the abiotic
and biotic compartments of aquatic
ecosystems is essential to
understanding the factors governing
this contaminant's biological
availability and assimilation in water.
Relative to most metals, mercury has a
much longer residence time in the
atmosphere. As a result, mercury is
mobile and readily dispersed through
the atmosphere, with the aquatic
cycling of mercury strongly affected by
exchange processes across the air-
water interface. Mercury can be
present as a dissolved constituent in
water, concentrated in the air-water
Water
HgO ^_
i
HgO
Hg(Ii)
& Inorganic
„. , , ^ ,
CHjBg + ——»*•
(From «
1-1
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National Mercury Survey
microlayer interface, attach-ed to plankton and suspended detritus, and present in bottom sediments
and benthos (Figure 1-1).
Mercury is biogeochemically active in natural waters, an expected characteristic, given the multiple
routes and reactions available for the interconversion of dissolved mercury species (Fitzgerald, 1989;
Andren and Nriagu, 1989). The three species, or oxidation states, of mercury prevalent in the aquatic
environment are:
• Hg° - elemental, or metallic, mercury
• Hg2+2 - mercurous ion, a divalent mercury form
• Hg+2 - mercury n, the mercuric ion, a divalent ion
In oxygenated waters supporting living organisms, mercury in the Hg+2 form generally dominates
and is rapidly removed from solution through adsorption to suspended solid and bottom sediments,
by binding to organic detritus, and through biotic assimilation. Mercury species form both organic
[i.e., methylmercury—CH3Hg+ and dimethylmercury (CH3)2Hg] and inorganic (mercuric chlor-
ide—HgCl2) compounds. Organic forms of mercury, such as methylmercury, exhibit longer
biological half-life than inorganic mercury; the half-life of methylmercury ranges from 1.5 years in
trout to approximately 2 years in pike (Ruohtula and Miettenen, 1971).
1.1.2 Methylmercury
All forms of mercury can be methylated by natural processes. Much of the methylmercury in the
aquatic environment is derived from internal, biologically-mediated synthesis. For example,
anaerobic sulfate-reducing bacteria, as well as aerobic bacteria and fungi, are major mediators of
methylation in sediment. Most methylation occurs in the sediment, but it can also occur in the water
column. Moreover, methylmercury is also produced when dimethylmercury, (CH3)2Hg, dissociates
in neutral or acidic conditions. Fish cannot methylate mercury in vivo, although methylation in the
gastrointestinal tract has been documented (Rudd et al., 1980).
Unlike dimethylmercury, methylmercury forms highly stable bonds. With a strong affinity for sulfur-
containing organic compounds (e.g., proteins) and ionic properties that facilitate penetration through
membranes, methylmercury bioaccumulates in fish and biomagnifies in aquatic ecosystems. While
it may comprise less than 30 percent of the total mercury in zooplankton, methylmercury accounts
for approximately 90 percent of the total mercury in fish (Huckabee et al., 1979). Excretion of
methylmercury is slow relative to the rate of uptake (Wiener, 1987), and no convincing evidence that
methylmercury is demethylated in fish exists (Weiner and Spry, 1994).
1.1.3 Methylmercury in the Aquatic Ecosystem
All water bodies in the Northern Hemisphere are probably contaminated with mercury due to long-
range transport and deposition from anthropogenic sources (Weiner and Spry, 1994). Predominant
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National Mercury Survey
exposure to methylmercury for fish is through diet, with direct uptake of methylmercury from water
across the gills providing minimal exposure. Exposure and accumulation of methylmercury in
aquatic organisms is subtly complex and influenced by numerous biotic and environmentally
mediated reactions. For example, piscivorous feeding habits, subsequent biomagnification in food
chains, and fish species, size, age, and longevity influence methylmercury concentrations in fish
tissues (Birge et al., 1977). Environmental factors, such as anthropogenic discharges, the form and
concentration of mercury, water temperature, low acid-neutralizing capacity, atmospheric deposition,
pH, dissolved oxygen levels, sedimentation rates in water bodies, proximity to wetlands, and the
flooding of new impoundments or reservoirs, are all factors affecting the exposure of fish to
methylmercury in the aquatic environment.
1.1.4 The Toxic Effects of Methylmercury
While the rates of bioassimilation of mercury vary due to biotic and abiotic factors, methylmercury
imparts the same toxic effects on all species. In fish, methylmercury binds to red blood cells and is
rapidly transported to all organs, including the brain, blood, spleen, kidney, and liver. Most
methylmercury ultimately accumulates in muscle, bound to sulfhydryl groups in protein (Weiner and
Spry, 1994). The route of uptake (e.g., via the gills or diet) has little influence on the bodily
distribution of methylmercury. The production of metallothioneins, metal-binding proteins that aid
animals by binding metal ions, are not induced by mercury in fish species (Roseijadi, 1992). Thus,
the primary detoxification mechanism in fish for methylmercury may be storage in the muscle rather
than storage in other sensitive and vulnerable tissues and organs (Weiner and Spry, 1994).
The effects of methylmercury in fish are well characterized and include death, reduced reproductive
success, impaired growth and development, behavioral abnormalities, organ and immune response
damage, altered blood chemistry, osmoregulation effects, reduced ingestion rates and predatory
success, and impacted oxygen exchange (Weiner and Spry, 1994; Zilloux et al., 1993). Prenatal and
neonatal life stages exhibit greater sensitivity, and the effects appear to be irreversible (Wiener,
1987). In fact, survival offish embryos has been shown to be substantially reduced by minute
quantities of either inorganic or organic mercury from waterborne exposure (Birge, 1977).
Neurotoxicity is the most likely chronic response of wild adult fishes to dietary methylmercury
(Weiner and Spry, 1994), with long-term dietary exposure to methylmercury causing lack of
coordination, inability to feed, and diminished responsiveness. Fish exposed to methylmercury in
laboratory situations, for example, exhibited several symptoms of methylmercury intoxication,
including loss of appetite, reduced activity, darkened skin, loss of equilibrium, reduced growth, and
reduced visual activity (Matida et al., 1971). Additional studies on fish from Minamata Bay, Japan,
have reported that the neurotoxic effects of methylmercury impede the abilities of wild fish to locate,
capture, handle, and ingest prey, and also impair the ability to avoid predation (Takeuchi, 1968).
For humans, epidemics of mercury poisoning following high-dose exposures to methylmercury in
Japan and Iraq demonstrated that neurotoxicity is the health effect of greatest concern when
methylmercury exposure occurs to the developing fetus. Dietary methylmercury is almost
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National Mercury Survey
completely absorbed into the blood and distributed to all tissues including the brain; it also readily
passes through the placenta to the fetus and fetal brain.
1.2 PURPOSE OF DATA COMPILATION
The potential adverse effects of chemical contaminants in fish is an ongoing Agency concern that
is directly related to Clean Water Act responsibilities to ensure that waters of the United States are
fishable and swimmable. As a percentage of total mercury, methylmercury is not problematic for
short-lived species, because the opportunity to accumulate mercury for periods of many years does
not exist. From an ecological perspective, however, mercury can bioaccumulate through the food
chain, resulting in body burdens that are higher than the baseline exposure concentrations; species
at higher trophic levels (e.g., humans, the bald eagle, and piscivorous fish species) prey on other
mercury-concentrating organisms (e.g., forage fish, which in turn feed on smaller forage fish, which
feed on zooplankton or benthic invertebrates). Bioaccumulation increases the likelihood that chronic
effects of mercury will impact the health and reproduction of organisms at higher trophic levels.
Although the degree of mercury bioaccumulation in fish tissues differs from watershed to watershed,
mercury contamination is becoming a national concern. Concern stems from information indicating
that methylmercury tends to bioconcentrate in fish tissue up to a million times or more over
concentrations found in the water column. In contrast to terrestrial animals, which concentrate
mercury in feathers or fur, fish populations concentrate mercury in muscle tissue. This aspect is of
particular concern to EPA, because edible tissues offish and other aquatic organisms may contain
mercury concentrations that exceed limits based on EPA risk assessment procedures for certain
consumption patterns.
As of July 1999,40 states had issued a total of 1,931 fish consumption advisories for specific water
bodies or for portions of statewide water bodies. Ofthese 1,931 advisories, 90% were issued by the
following 11 states: Minnesota (821), Wisconsin (402), Indiana (126), Florida (97), Georgia (80),
Massachusetts (58), Michigan (53), New Jersey (30), New Mexico (26), South Carolina (24), and
Montana (22). Ten states (Connecticut, Indiana, Maine, Massachusetts, Michigan, New Hampshire,
New Jersey, North Carolina, Ohio, and Vermont) have issued statewide advisories for mercury in
their freshwater lakes and rivers. Another five states (Alabama, Florida, Louisiana, Massachusetts,
and Texas) have statewide advisories for mercury in their coastal waters.
Regulatory and scientific focus on mercury in the aquatic ecosystem has been motivated largely by
the health risks of consuming contaminated fish, primarily because human exposure to
methylmercury is almost wholly due to fish (Fitzgerald and Clarkson, 1991; Clarkson, 1992). While
mercury contamination poses potentially serious human health and ecological problems,
understanding of the problem is still relatively limited. The ability to determine the nature and the
extent of mercury concentrations in fish on a regional and national basis, to identify possible sources
of contamination, and to link mercury concentrations to sources depends on the availability of data
suitable for such analysis.
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National Mercury Survey
To help fill this need, EPA began a cooperative effort in 1995 to assemble a nationwide data base
on total mercury concentrations in fish tissue. The first objective of this project was to assemble and
review data on the mercury contamination in fish tissue. This step included identifying appropriate
state and federal agencies and other groups with relevant data on mercury concentrations in fish. The
second step in this project involved the development of a fish tissue data base, organizing relevant
data to be used for future analyses. EPA focused data compilation efforts on obtaining results of
state monitoring efforts during 1990-1995 (See Appendix). These data can be used to derive
estimates of tissue concentrations, determine the number and frequency of samples taken and
analyzed by state, and calculate descriptive statistics on mercury concentrations in fish tissue. The
current data base will facilitate EPA's ability to determine additional and future data needs. In the
future, the data base may be used to identify and evaluate factors affecting mercury contamination
in fish.
1.3 THIS DOCUMENT
This document describes the national mercury data base compiled and quality assured by EPA's
Standards and Applied Science Division within the Office of Water's Office of Science and
Technology. In addition to this introduction, this document contains a description of the data base
(Section 2.0), including an overview of the data base format, inconsistencies among data sets, and
a discussion of the steps taken to standardize and ensure data quality. Section 3 describes the data
base in detail and provides a national overview of the types of data contained in the data base and
a summary of mercury concentrations in selected fish species. Section 3 also presents state profiles;
for each state included in the data base, a four-page graphical and tabular summary is provided.
Each summary presents sampling information (e.g., the number offish and sites sampled); details
on the ten most common species and other variables related to fish that are contained in each state
data set; sampling sites and range in mercury concentration across each state for those reporting
latitude and longitude; and summary statistics on fish mercury content. Section 4 describes issues
relevant to analysis of the data, including treatment of nondetects, and provides a brief discussion
of the potential future uses of the data base. Section 5 lists the references consulted in preparing this
report.
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SECTION 2
DATA BASE STRUCTURE AND FORMAT
2.1 OVERVIEW OF THE DATA BASE
Data from 40 states and the District of Columbia comprise the national data base on total mercury
concentrations in fish tissue. The data are broadly categorized into three groups, providing location,
biological, and mercury concentration information. The principal features of the national data base
on mercury concentrations are:
• Fish tissue samples collected from 1990 to 1995, inclusive.
• Location information, with most states providing latitude and longitude.
• Common and scientific names for fish species.
• Total mercury concentrations greater than zero. If the mercury concentration was labeled as
"non-detected" or as less than a given value, the detection limit or the given value was used
to estimate mercury concentration.
• Weighted mercury concentrations in fish tissues. For composite samples, the number offish
in the composite was used as the weighted value. For samples comprised of a single fish, or
samples where composite information was not available, a weight of one (1) was assigned.
States not included in the data base either could not provide information on mercury concentrations
in fish (i.e., Alaska, Colorado, Hawaii, Idaho, Nevada, North Dakota, Wyoming, and Utah), or
provided data in hard copy reports (i.e., Montana and South Dakota). Mercury data available only
in hard copy reports were not included in the data base because the data in hard copy reports
frequently did not contain complete information. Furthermore, manually entering the data from hard
copy into an appropriate electronic format, obtaining missing information, and performing quality
control checks on the data would have been prohibitive, given the schedule and scope of work for
this project.
2.2 DATA BASE FORMAT
The compiled data were imported initially into SAS® from various formats. To make the data base
more widely accessible, a relational data base was constructed in Microsoft Access 97. The Access
data base has been updated with new data from several of the states and has been subjected to
additional quality control and assurance and overall standardization. Table 2-1 lists the states that
comprise the national data base on mercury concentrations in fish tissue, as well as the primary
source of the data (i.e., state or STORET). A list of the data fields in Access 97 and a short
explanation of the data contained in the field are provided in Table 2-2.
2.3 INCONSISTENCIES AMONG DATA SETS
After identifying, obtaining, and verifying data from the appropriate sources, discrepancies among
state data were identified by visually examining each data set. Consistency in the formatting of data
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National Mercury Survey
Table 2-1. The National Survey of Mercury Concentrations in Fish:
Data Base Sources'1
State Name
AL
AZ
AR
CA
CT
DE
DC
FL
GA
IL
IN
IA
KS
KY
LA
ME
MD
MA
MI
MN
MS
MO
NE
NH
NJ
NM
NY
NC
OH
OK
OR
PA
RIb
SC
TN
TX
VT
VA
WA
WV
WI
State Data
Primary
Primary
Primary
Primary
Primary
Primary
Primary
STORET Data
Combined data sets
Combined data sets
Primary
Primary
Primary
Primary
Combined data sets
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Combined data sets
Primary
Primary
Primary
Combined data sets
Primary
Primary
Primary
Primary
Primary
Primary
Primary
Data not available for AK, CO, HI, ID, MT, ND, NV, SD, UT, and WY.
Rhode Island data are for 1996 through 1998 and are included in the data base, but are not
addressed in this report.
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National Mercury Survey
Table 2-2. The National Survey of Mercury Concentrations in Fish:
Data Base Field Descriptors
Field
State
Water Body
County
Location
Latitude
Longitude
Agency
Collection Date
Date
Common Name
Genus
Species
Sample Type
Number in
Sample
Mean Length
Total Length
Mean Weight
Total Weight
Portion
Standardized
Portion
Detection Limit
Mercury Basis
Mercury
Concentration
Dry_Wet
Conversion
Fillet
Conversion
Wet_Fillet
Concentration
Qualifier
Description
State name
Water body name
County name
Description of location where the sample was taken
Latitude in decimal degrees
Longitude in decimal degrees
Federal or state collection agency responsible for sampling
Date sample was collected
Sampling date presented in Access Date/Time format
Common name
Genus name
Species name
Indicates whether sample type is composite or specimen
Total number of fish that comprise a sample
Length of individual or mean length for a composite sample
(mm)
Total length of sample (mm)
Mean weight for a composite sample (g)
Total weight for a specimen (g)
Identifies the organ or portion of fish analyzed
Assigns each portion type into one of four categories
Detection limit (ppm)
Indicates whether mercury was measured on a wet or dry
weight basis
Mercury concentration measured in fish tissue (ppm)
Tissue concentrations on a dry weight basis were converted
to wet weight for comparison purposes
Some states reported whole body concentrations of mercury
rather than fillet concentrations. For comparison purposes,
the whole body mercury concentrations were converted to
fillet.
Presents the tissue data (Whole body, Fillet and Unknown)
on a wet weight and fillet basis
Descriptive information accompanying the mercury value
Example
Alabama
Tens aw River
Berkshire
Mobile River, river mile 27.0
39.2521
-95.0812
Ohio Department of Health
12/21/93=931221
12/31/93
Largemouth bass
Micropterus
salmoides
Composite or Specimen
3
355.00
1777.00
690.00
910.00
Fillet, skin off; Whole body, etc.
Whole body, Fillet, Other, Unknown
0.001
Wet or Dry
0.570
Wet Weight = Dry Weight x (1-
%moisture)
Cr = Cwb -f 0.7
Where,
Cr = Fillet Hg concentration
C,* = Whole body Hg concentration
0.570
"Less than" or "estimated"
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National Mercury Survey
sets from state to state is the most important requirement in establishing a well-structured national
database. Some of the principal inconsistencies and discrepancies encountered are discussed below.
2.3.1 Missing Data or Blank Fields
Very few state data sets submitted initially contained all the requested data fields. Some states could
not send the requested data because such data were not collected. Others were able to send the
additional information, and in some cases a completely new version of the data set was submitted.
If the state could not supply additional data, STORET was searched in an effort to augment the data
set. This standardization process resulted in obtaining some additional latitude and longitude data.
EPA attempted to standardize the data to make the data base as complete as possible. For example,
some states provided only the year, or the year and month of the sample collection date. The month
of January and/or the first day of the month (01) were assigned as necessary to form a complete value
for the variable Collection date in the data base.
2.3.2 Differing Data Structures
In addition to differing software packages, the format or structure of the data sets varied from state
to state. For example, field descriptor names differ across states. Furthermore, the same field names
may define the same, or different, variables. Empty entries in data sets also vary from state to state.
In some state data set formats, empty entries denote missing values. However, in other state data
formats, empty entries imply that the values for the empty entry are the same as the prior nonempty
value. The disparities among state data structures and field names typically cannotbe discerned until
the given format for several state data sets is thoroughly examined. Improving the consistency
among state data base formats, such as through the use of EPA's modernized STORET data system,
would greatly enhance comparability and synthesis of data on a national scale.
2.3.3 Differing Coding Systems
A fairly common discrepancy among the state data sets is that each state has a different coding
system. Lack of explanation for the codes hinders the standardization, and additional contact with
the state was necessary to interpret codes for several fields, including common name, fish species,
portion analyzed, collection agency, county, and qualifier. Some state data sets contain only the
common name and do not contain a key that cross references the associated scientific name. Other
records that frequently differed:
• fish length, for which different units were given—inches, centimeters, or millimeters;
• fish weight—pounds or grams;
• common name/species/genus—Carp or Common carp/Cyprinus or C./carpio
• mercury concentration—ppm or ppb
• latitude and longitude—degree-minute-second or decimal degrees; and
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National Mercury Survey
• length and weight measurements—total length and total weight of fish or composite or mean
length and weight of the composite
2.4 STANDARDIZATION OF VARIABLES
Standardizing the variables in each state data set consisted of the following activities:
• Three fields are associated with identifying fish species: common name, genus name, and
species name. Most states only provided common names using different coding schemes. In
order to standardize the names, genus and species names were assigned to the common names.
The first step in this process used a data sheet containing both common names and scientific
names as designated by the American Fisheries Society (AFS). All common names were
matched electronically to identical common names. In cases where names did not match,
taxonomy literature and best professional judgement were used to identify the genus and
species. Some states supplied common names that had been coded for their data management
system without providing an accompanying key to the coding system. For example, one state
may have used "LMB" for largemouth bass or assigned a numeric code to a common name,
and a follow-up contact with the state was required to obtain information on the coding system.
• The portion analyzed was standardized from the state data set into the national data base and
then again for the analysis presented in this document. The standardized portion code in the
data base and the portion code used for mercury concentrations analyses are shown in the
following table. Other entries for portions analyzed that were supplied by states included
connective tissue, eggs, eyes, gills, gonads, liver, head and viscera, no head or viscera, no skin,
and veins. These entries were retained as is in the data base, but they were eliminated for
analyses involving whole-body and fillet mercury concentration comparisons.
Table 2-3. Standardized Portion Codes
Portion Code in
State Data base
Edible portion, edible, edible skin-off
F, Filet, FS, PF, SFF, SFFC
F, FILSK, Fillet-skin-on, SOF, SOFC
86, F, Fl, F2, Meat, Fillets
Headless whole fish
15, 59, MWBC, WB, WBC, whole fish
Whole body, skin off
Whole body, skin on
Standardized Portion
Code
Edible portion
Fillet, skin off
Fillet, skin on
Fillet, skin unknown
Headless whole fish
Whole body
Whole body, skin off
Whole body, skin on
Portion Code Used
in Analyses
Fillet
Fillet
Fillet
Fillet
Whole body
Whole body
Whole body
Whole body
Values for latitude and longitude were converted to decimal degrees, such as 39.2522 and
95.3267. This process entailed converting the degree, minute, second or the radian format
supplied by most states to decimal degrees by the following equations:
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Lat_decimal = Lat_deg + Lat_min / 60 + Lat_sec / 3600
Long_decimal = Long_deg + Long_min/60 + Long _se c / 3600
For some states, the variable water body was provided. In situations were this variable was not
provided, it was derived from location information provided by the state. For example, if the
location information provided was "Mississippi River at RM 37.0," the water body derived was
the Mississippi River.
Qualifiers are descriptive information accompanying the mercury concentration measurement,
such as "ND," "non-detected," and "less than." These qualifiers were standardized across all
state data sets. The following table provides some examples of the different values in this field
in state data sets assuming the detection limit is 0.02 ppm.
Table 2-4. Examples of Qualifiers for Mercury Concentrations
Mercury
Concentration
(Provided by the State)
ND
0.01
0.02
-
0.02
Qualifier
(Provided by the State)
half the detection limit
less than, or <
ND, or not detected, NA
estimated
Standardized Mercury
Concentration
0.02
0.02
0.02
0.02
0.02
Standardized
Qualifier
Non-detected
Non-detected
Less than
Non-detected
Estimated
Units of length, weight, and mercury concentrations were standardized to millimeters, grams,
and ppm, respectively. Simple mathematical conversions were performed in this standard-
ization task. Length and weight measurements are given as total and/or mean. Some states did
not provide information regarding whether length and weight measurements were total or
mean. In instances where this could not be discerned or when these were not supplied, the
state was contacted for clarification.
For some states, fish tissue mercury concentrations were provided on a dry weight basis. An
additional column was added to the data base (Dry_Wet Conversion) that converts the
concentrations on a dry-weight basis to a wet-weight basis to enable data comparisons. The
follow equation was used to perform the conversion calculation:
Wet weight = Dry Weight x (1 - O.xxx)
where:
2-6
-------
National Mercury Survey
Wet weight = mercury concentration by wet weight in mg/kg tissue
Dry weight = mercury concentration by dry weight in mg/kg tissue
O.xxx = percent moisture in fish tissue expressed as a decimal (e.g., 75% = 0.75)
Moisture content varies in fish based on numerous factors such as age and species, and because
moisture content is not included as a variable in the data base, all conversions were made with
an assumed moisture tissue percentage of 78.5% (0.785). This value was based on the
arithmetic mean of the moisture contents of coho salmon (85%), kokanee (74%), lake whitefish
(80%), pike (78%), white sturgeon (78%), and sockeye salmon white muscle (fillet, 76%)
(B.C. Environment, 1998; McDonald, 1997).
The fish tissue data consist primarily of analyzes of mercury concentrations in fillets. Some
states, however, provided data on the basis of whole body measurements. To facilitate
comparisons between tissue and whole-body measurements, the following empirically-derived
equations from Bevelheimer et al. (1996) were used:
where:
CWb = whole-body mercury concentration in mg/kg
Cf = fillet mercury concentration in mg/kg
A field (fillet conversion) was added to the data base that contains the results of the calculation
above, solved for Cf only for those records where the mercury concentration was measured
based on whole body measurements.
2.5 GENERAL QUALITY ASSURANCE/QUALITY CONTROL
The first step in quality assuring the data was to identify the appropriate data source for each state.
States either maintained collected data within the state agency and/or submitted mercury
concentrations in fish tissue data directly to STORET, a nationally maintained ambient water quality
data base. Data downloaded by the state from the STORET system and sent in an electronic or hard
copy format are considered "STORET" data. Data maintained by the state agency in house and not
submitted to STORET are considered "state" data. State-collected data on mercury concentrations
in fish tissue were available from most states in electronic or hard copy formats, or both.
EPA quality assured STORET data while trying to obtain missing data fields from STORET and
BIOS, another national data base containing fish species information that is compatible with
STORET maintained on EPA's mainframe computer. STORET and BIOS were searched on the
EPA mainframe, and the resulting data were compared to STORET data sent by the state. When
possible, STORET data from the mainframe were used to augment incomplete data sets received
2-7
-------
from the state. This action resulted in five (5) states with combined data sets from 1990 - 1995, as
shown in Table 2-2.
Following completion of the data standardization process, additional quality assurance measures
were performed before performing any analysis on the data base. For example, the mercury
concentration field was carefully scrutinized. Unreasonably high mercury concentrations (e.g., 140.0
ppm and 220.0 ppm) were identified and subsequently dropped from the data base when
scientifically valid explanations could not be identified. Other suspicious mercury concentrations
(13.3 ppm, 5.95 ppm, and 5.83 ppm) identified were noted in the data base but were not dropped
because reasonable justifications could not be identified. In one instance, values for a chemical other
than mercury that had been sent were identified and substitute data were provided by the state.
Additional errors in fields such as sampling date, latitude, and longitude also were discovered and
corrected, following confirmation with the state contact.
2-8
-------
National Mercury Survey
SECTION 3
NATIONAL AND STATE OVERVIEW
3.1 NATIONAL OVERVIEW
The District of Columbia and 40 states are represented in the electronic version of the national
mercury data base. The sampling sites in the data base for which latitude and longitude are available
are depicted on the national map in Figure 3-1.
Figure 3-1. Sampling Locations with Latitude and Longitude
West
* * "^ Is i
''ft .P:
"'•^x
x .- -.. • • y-*
f"
East
K^^rs (fi$
^»---' ;•«.:5rt,
• /JZJ^-^S
-->t^T,- .'*.::^
« rty.. ' , ' •'
B. s*^;*£| ". ' n^-, ,t
s«w- v•"••"''"-.r- &. X'~H-?
V
KfJSS^-f/,1
\ - :Ljn,v^,lt—Jt*)U»»--^ ..
\!.../ v-i-r *• •;•_ »,'. "s-i
^V4'
i«i *^"
3.1.1 Availability of Data Variables
Table 3-1 summarizes the variables that are present in, or absent from, the national data base.
Varying combinations of data on location, biology, and mercury are available in the electronic data
base for 40 of the 50 states plus the District of Columbia. Data are available in hard copy only for
Montana and South Dakota, and they have not been incorporated into the electronic data base. For
Rhode Island, data records for the years 1996 through 1998 are included in the data base, but are not
addressed in this report. Data on mercury concentrations in fish are not available for Alaska,
Colorado, Hawaii, Idaho, Nevada, North Dakota, Utah, and Wyoming.
3-1
-------
National Mercury Survey
Table 3-1. The National Survey of Mercury Concentrations in Fish:
Presence/Absence of Variables in Data Base
Location Information
Biological Information
Mercury Information
State
Site
Lat/
Long
Water-
body
Date
Taxon
Wt.
Length
Comp.
vs. Spec.
Portion
Analyzed
Weight
Basis
Cone.
Units
AL
AZ
AR
CA
CT
DE
DC
FL
GA
IL
IN
IA
KS
KY
LA
ME
MD
MA
MI
MN
MS
MO
MT
NE
NH
NJ
NM
NY
NC
OH
OK
OR
PA
SC
SD
TN
TX
VT
VA
WA
WV
WI
a Data not available for AK, CO, HI, ID, ND, UT, and WY; see text for note on RI.
X = Data available only in hard copy reports. Not included in data base.
/ = Data available electronically in data base.
Location data are included in four variables: site, latitude, longitude, and water body name; the
sampling date is also provided in this category of variables in Table 3-1. Most of the location
information is included in the electronic data base for 40 of the 50 states and the District of
3-2
-------
National Mercury Survey
Columbia, with the level of detail describing location and water body varying among states. Of the
four location variables, latitude and longitude for the sampling site are the most frequently missing
variables. Latitude/longitude are missing from the electronic database for Massachusetts, Michigan,
Missouri, New Jersey, New Mexico, Ohio, Oregon, and West Virginia.
Biological data are included in the following variables: taxon; weight and length of a specimen (an
individual fish) or average weight and length (if the sample is a composite); whether the sample
represents a composite of more than one fish or a single individual, or specimen; what portion of the
fish is analyzed (i.e., whole body, fillet); and whether the mercury content is expressed on a wet
weight basis or dry weight basis (or both). Of these variables, length is the most commonly missing
variable, absent from 12 states. All states and the District of Columbia in the national data base
report the portion analyzed, and, with the exception of New Jersey, all report the weight basis of the
fish tissue analyzed.
Mercury data are included in four variables: concentration, units, detection limits, and comments
associated with the mercury concentration (e.g., "less than"). These four data variables are included
in the electronic data base for the 40 states and the District of Columbia.
3.1.2 Type of Sampling and Analysis
Table 3-2, similar to Table 3-1, presents information on the presence or absence of sample type (i.e.,
composite or specimen), portion of the fish analyzed, and the basis on which mercury concentrations
are reported. Sample type includes: individual, composite, and in the case of composites, whether
the number offish in the composite is reported. With two exceptions (Florida and Tennessee), all
states provided data on sample type as well as on the number offish in the composite. When the
number offish in the composite was not specified, the number was assumed to be one.
The portion analyzed includes whole body, fillet, or "other"; other includes gonads, internal organs,
eggs, etc. All states analyzed the fillets of the fish for mercury, while several others elected to
analyze whole body portions as well. Mercury concentrations are reported on a dry weight basis or
a wet weight basis. The vast majority of states measure and report mercury on a wet weight basis.
3.1.3 Extent of Sampling
The national data base for 1990-1995 includes data for nearly 82,000 individual fish (representing
230 different species) at approximately 5,000 locations in approximately 3,200 water bodies. Table
3-3 summarizes the number of discrete water bodies, stations, number of species analyzed, and total
fish analyzed from 1990 through 1995 by state. Most states have data for at least five of these years,
many have sampled for all six years, and only a few have sampled for two or fewer years. In many
cases, the number of water bodies sampled and the number of sampling station locations are
approximated from available data submitted by the state. Minnesota, Michigan, Wisconsin, Florida,
Arkansas, and California conducted the most sampling during 1990-1995, as measured by the
number of water bodies sampled. Broad comparisons among states are not appropriate, because
states differ both in terms of geographic size and total amount of surface water.
3-3
-------
National Mercury Survey
Table 3-2. The National Survey of Mercury Concentrations in Fish:
Presence/Absence of Fish and Mercury Information in Data Base
State"
Sample Type
Specimen
Composite
Sample
No. in
Composite
Portion Analyzed
Whole
Body
Fillet
Other
Weight Basis
Wet
Dry
AL
AZ
AR
CA
CT
DE
DC
FL
GA
IL
IN
IA
KS
KY
LA
ME
MD
MA
MI
MN
MS
MO
MT
NE
NH
NJ
NM
NY
NC
OH
OK
OR
PA
SC
SD
TN
TX
VT
VA
WA
WV
WI
a Data not available for the following states: AK, CO, HI, ID, NV, ND, UT, and WY; see text for note on RI.
X = Data available only in hard copy reports. Not included in data base.
/ = Data available electronically in data base.
3-4
-------
National Mercury Survey
Table 3-3. The National Survey of Mercury Concentrations in Fish:
Number of Records and Years in Data Base
State"
AL
AZ
AR
CA
CT
DE
DC
FL
GA
IL
IN
IA
KS
KY
LA
ME
MD
MA
MI
MN
MS
MO
NE
NH
NJ
NM
NY
NC
OH
OK
OR
PA
SC
TN
TX
VT
VA
WA
WV
WI
Number of
Discrete
Water bodies
Sampled
89
2
161
176
54
19
2
194
94
3
49
53
69
13
73
120
41
24
142
449
83
81
85
63
58
37
36
103
106
59
36
135
74
46
65
55
14
12
18
204
Discrete
Stations
Sampled
141
2
222
223
54
29
7
273
208
66
119
75
85
45
97
125
60
24
254
637
112
129
115
66
63
37
42
162
497
94
66
192
130
69
86
55
48
14
39
294
Species
Analyzed
24
5
29
48
4
16
8
36
44
13
43
10
15
27
38
13
22
5
36
41
23
29
14
14
14
28
22
43
44
37
31
28
26
17
33
16
21
11
20
39
No. of
Fish
Analyzed
2236
51
2389
4914
618
190
75
2819
3412
458
1987
549
755
1323
1093
1557
799
550
5063
21537
1127
2077
1022
199
373
467
993
4640
4739
2916
935
1127
826
297
673
514
676
164
428
4659
Year Reported
1990
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
1991
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
1992
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
1993
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
1994
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
1995
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
/
Electronic data not available for AK, CO, HI, ID, MT, NV, ND, SD, UT, and WY; see text for note on Rhode
Island.
/ = Data for given year are available in data base.
3-5
-------
National Mercury Survey
3.1.4 Mercury Concentrations in Selected Fish Species
Measured by the total number offish analyzed, the top six species represented in the national data
base are largemouth bass, walleye, northern pike, channel catfish, bluegill sunfish, and common carp.
Figure 3-2 depicts the weighted mean mercury concentration and selected points on the frequency
distribution for each of these species on a national basis. Three features are evident from this
analysis in direct relationship to increasing trophic level of species: (1) the weighted mean
concentration and overall frequency distribution increases, (2) the spread of concentration values
increases, and (3) there is greater separation between the weighted mean and median value of the
distribution. This analysis indicates that both the magnitude and variability of mercury concentration
values are greater in higher trophic level fish species, as would be expected of the data.
Figure 3-2. Concentration Ranges of Mercury in Tissues of Selected Fish Species. |
1.40
C^ 1.20
•a
1.00
0.80
0.60
0.40
0.20
0.00
D
— ±—
9
A
9
A
m
|— •— 1
Q •"*.•:::::::::..... Q Q
Largemouth Walleye Northern Channel Bluegill Common
bass pike catfish sunfish carp
Table 3-4 presents the mean mercury concentrations in parts per million (ppm) in selected species
offish. The ranges in average mercury concentrations (ppm) for these fish are presented in Table
3-5. Comparisons of mercury concentrations within a given fish species across states may not be
strictly appropriate for several reasons: sampling strategies (representative versus targeted) may
differ; analytical procedures may not be consistent from state to state; mercury concentrations may
vary with age of the fish—a variable that may not have been controlled in the sampling; and some
mercury analyses may have been performed on either fillets or the entire fish body. Nevertheless,
qualitative observations on the ranges of mercury concentrations within a given species are
informative.
3-6
-------
National Mercury Survey
Table 3-4. The National Survey of Mercury Concentrations in Fish:
Mean Mercury Concentrations (ppm) in Major Fish Species a'b
State0
AL
AZ
AR
CA
CT
DE
DC
FL
GA
IL
IN
IA
KS
KY
LA
ME
MD
MA
MI
MN
MS
MO
NE
NH
NJ
NM
NY
NC
OH
OK
OR
PA
SC
TN
TX
VT
WA
WV
WI
Largemouth
Bass
0.393
1.369
0.675
0.281
0.501
0.108
0.153
0.645
0.274
0.180
0.264
0.189
0.583
0.391
0.634
0.021
0.399
0.431
0.240
0.651
0.257
0.343
0.573
0.664
0.428
0.462
0.532
0.142
0.684
0.369
0.293
0.994
0.255
0.237
0.802
0.137
0.369
Smallmouth
Bass
0.257
0.313
0.653
0.094
0.235
0.782
0.110
0.391
0.292
0.232
0.766
0.244
0.629
0.550
0.173
0.366
0.259
0.560
0.226
0.343
Walleye
0.371
0.110
0.514
0.132
0.375
0.324
0.348
0.168
0.875
0.142
0.239
0.612
0.440
Northern
Pike
0.509
0.304
0.381
0.270
0.477
0.377
0.317
Channel
Catfish
0.214
0.473
0.143
0.050
0.091
0.084
0.183
0.104
0.125
0.147
0.111
0.033
0.047
0.266
0.274
0.052
0.109
0.228
0.297
0.195
0.118
0.193
0.284
0.345
0.173
0.193
0.130
0.450
Bluegill
Sunfish
0.606
0.310
0.057
0.350
0.010
0.058
0.110
0.236
0.147
0.132
0.084
0.347
0.169
0.186
0.097
0.126
0.359
0.095
0.378
0.050
0.131
Common
Carp
0.138
0.061
0.082
0.136
0.166
0.215
0.167
0.231
0.100
0.031
0.181
0.089
0.186
0.128
0.167
0.274
0.192
0.200
0.124
0.133
0.245
0.145
0.208
0.154
0.179
0.178
White
Sucker
0.060
0.137
0.133
0.338
0.049
0.117
0.103
0.141
0.138
0.456
0.095
0.107
0.114
Yellow
Perch
0.190
0.049
0.067
0.333
0.306
0.142
0.346
0.488
0.477
0.210
0.129
0.332
0.150
Note: If the number offish in the composite sample is missing, a value of 1 was assumed.
Weighted Mean xw = E, wpct I E,-vf,., where w is the weight (# offish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Electronic data not available for AK, CO, HI, ID, MT, ND, NV, SD, UT, and WY; see text for note on RI.
3-7
-------
National Mercury Survey
Table 3-5. Range of Mean Mercury Concentrations
(ppm) for Major Fish Species a
Largemouth bass
Smallmouth bass
Walleye
Northern pike
Channel catfish
Bluegill sunfish
Common carp
White sucker
Yellow perch
0.001-8.94
0.008-3.34
0.008-3
0.10-4.4
0.001-2.57
0.001-1.68
0.001-1.8
0.002-1.71
0.01-2.14
a These ranges represent fish tissue mercury concentrations on a wet
weight and fillet basis.
Although the general pattern of predators having greater weighted mean concentrations than bottom
feeders also occurs for state-specific data, substantial variations among states exist for weighted
means of representative bottom feeders and especially for predators. State-specific weighted means
for bottom feeders (such as channel catfish or common carp) usually fall in the 0.1 to 0.3 ppm range,
whereas weighted means for predators (such as largemouth and smallmouth bass) usually fall in the
0.2 to 0.7 ppm range. No clear regional pattern emerges from this particular analysis of the data.
3.2 STATE PROFILES
The decision to compile data for the 1990-1995 time period results in the exclusion of a substantial
amount of high-quality data for some states. For example, the number of samples from New York
summarized in this report represents only a fraction of the sampling performed from 1970 to the
present in that state. An excellent summary of the complete New York data base, as well as other
northeastern states, is presented inNESCAUM (1998). For most states, the 1990-1995 time period
accurately captures the first years of high-quality mercury sampling and analysis. This report
presents state-by-state profiles of detailed information on the data collected by states during a
constant period of time.
In compiling these summaries, only the years 1990 through 1995 were included, as stated above.
All mercury concentrations were expressed on a wet basis and fillet basis. All non-fish species, such
as crayfish, oysters, rock crab, and snapping turtle were excluded. In addition, for the top ten fish
species analysis and for the analysis of mercury concentration in the top three species, species
identified as "unknown" or "mixed" and mercury concentrations determined on the tissue portion
coded as "other" (e.g., gonads, internal organs, eggs, etc.) were excluded.
3-8
-------
National Mercury Survey
For each state included in the data base, a separate four-page pictorial and tabular summary
describing the data base is presented on the following pages. Each state summary page includes the
state name and the source of the data (either a state-maintained data base, STORET, or a
combination of both) in the heading spanning the pages.
On the first page of the summary, the total number offish analyzed and the total number of samples
taken for each year represented in the data base are presented. To the right of this bar chart is a state
map depicting the locations of the sampling sites for those states reporting latitude and longitude
data; maps for states that do not report the latitude and longitude data are presented as state
boundaries only. On the bottom half of the first page, the number of records of location variables
are presented. The number of observations, along with the percentage that each variable represents
in the data set for that state, are given. A table of the ten most common fish species sampled in the
state is presented on the top of the second page of each state summary. At the bottom of the second
page, the fish data variables are presented.
At the top of the third page of each state summary is a map depicting the geographical distribution
of mercury concentrations across the state. Maps for states that do not report the latitude and
longitude data are presented as state boundaries only. Total mercury concentrations in ppm are
categorized as (1) greater than 1.0 ppm, (2) 0.5 to 1.0 ppm, and (3) less than or equal to 0.5 ppm.
Closed squares represent mercury concentrations in class 1, shaded circles represent mercury
concentrations in class 2, and closed triangles represent mercury concentrations in class 3.
At the bottom of the third page, variables that pertain to mercury are presented. For any one state,
the variables that may be contained in the data base include the detection limit of the analytical
method, the mercury reporting basis (wet weight or dry weight), the mercury concentration, and any
qualifying flags regarding the mercury data value, such as "less than" the detection limit. All
measurements in the data base reflect analysis for total mercury.
The fourth page of each state summary contains a tabular presentation of mercury concentration for
the three most abundant fish species sampled. Mercury concentrations are expressed on a wet basis
and a fillet basis. The common name, number of samples, and number offish are included. For each
of the three species, summary statistics that describe the mercury concentrations are given. These
statistics include the minimum, maximum, weighted mean, and weighted median concentrations of
mercury in ppm. Statistics that describe the variability in the mercury concentrations are also
presented: the weighted standard deviation and the coefficient of variation. When the number offish
in a composite sample was omitted from the record, a value of 1 was assumed. The definitions of
the statistics and formulas used to derive their values are given at the bottom of the table.
At the bottom of the fourth page of each state summary is a graphic showing the cumulative
distribution of mercury concentrations for all fish species, expressed on a wet weight basis and on
a fillet basis.
3-9
-------
Alabama
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
f_ -Jg—__
1 • • *
Location Variables in Database
100
80
a
s
•s 60
HI
Q.
20
Number of records:
472
472
472
472
472
Water body Location
Latitude Longitude Agency
3-10
-------
Alabama
Data Source: State
Top Ten Fish Species
Common Name
Largemouth bass
Channel catfish
Blue catfish
Black crappie
Spotted bass
Percent
41
31
8
7
5
Common Name
Flathead catfish
Spotted sucker
Brown bullhead
Blacktail redhorse
Redeye bass
Percent
2
1
1
<1
<1
Fish Variables in Database
Number of records:
472 472 402 70 472 402 70 402 70 472 0 0
3-11
-------
Alabama
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
.E 80
60
HI
O)
I
§ 40
20
Detect, limit Hg basis-Wet Hg basis - Dry Hg cone.
Qualifier
3-12
-------
Alabama
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Channel catfish
Blue catfish
No. of
Samples
180
149
39
No. of
Fish
914
702
178
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.100
0.100
0.100
Max
(ppm)
1.630
0.660
0.500
Wt.
Mean
(ppm)b
0.393
0.214
0.189
Wt.
Median
(ppm)
0.380
0.100
0.100
Wt.
SDW<
0.301
0.165
0.165
cv
(%)"
76.49
76.97
87.69
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(x.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Alabama
100-
90 -.
80-
70.
en
50 ~
40:
30:
20-
10 -_
0
0.0 0.2 0.4 0.6 0.8 1.0 1.2
Mercury Concentration in Fish (ppm)
1.4
1.6
1.8
3-13
-------
Arizona
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
100
80
o
Q.
60
v
O)
re
«
Q.
20
Location Variables in Database
Number of records:
51
51
51
Water body Location
Latitude Longitude
Agency
3-14
-------
Arizona
Data Source: State
Top Five Fish Species"
Common Name
Largemouth bass
Yellow bullhead
Redear sunfish
Bluegill sunfish
Black crappie
Percent
69
12
10
6
4
Only five species were identified in the data base.
Fish Variables in Database
Number of records:
51 51 0 51 51 0 10 51 51 0
100
I
I 8°
8
ro
? 60
0)
I 40
«
20
3-15
-------
Arizona
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
L,
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
100
o
Q.
80
60
01
O)
3
8 40
20
Number of records:
631
631
631
/
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-16
-------
Arizona
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Yellow bullhead
Redear sunfish
No. of
Samples
35
6
5
No. of
Fish
35
6
5
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.700
0.340
0.280
Max
(ppm)
2.620
0.890
0.690
Wt.
Mean
(ppm)b
1.369
0.522
0.460
Wt.
Median
(ppm)
1.240
0.500
0.400
Wt.
SDW<
0.458
0.204
0.177
cv
(%)"
33.46
39.03
38.49
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(jc.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Arizona
100-
90--
80--
70--
:
60-.
:
50 -
20--
o-
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-17
-------
Arkansas
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
• ' » v . • •
•• .* . •
• t
nv^?
Location Variables in Database
100
E 80
60
HI
Q.
20
Number of records:
829
Water body
829
828
828
829
Location
Latitude
Longitude
Agency
3-18
-------
Arkansas
Data Source: State
Top Ten Fish Species
Common Name
Largemouth bass
Black bass
Spotted bass
Bluegill sunfish
Channel catfish
Percent
50
7
6
5
5
Common Name
White crappie
Black crappie
Crappie
Spotted sucker
Flathead catfish
Percent
4
4
3
2
2
Fish Variables in Database
Number of records:
829 829 516 304 820 513 304
498 298 829
,o\\»'
3-19
-------
Arkansas
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
• *• •• *
Vr?
" 0.5 to 1
A < = 0.5
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Mercury Variables in Database
Number of records:
Detect, limit Hg basis-Wet Hg basis - Dry Hg cone.
Qualifier
3-20
-------
Arkansas
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Black bass
Spotted bass
No. of
Samples
440
32
50
No. of
Fish
1190
157
132
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.030
0.100
0.170
Max
(ppm)
3.170
1.360
1.720
Wt.
Mean
(ppm)b
0.675
0.640
0.622
Wt.
Median
(ppm)
0.560
0.580
0.600
Wt.
SDW<
0.486
0.308
0.261
cv
(%)"
72.03
48.11
42.04
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wpc, / £,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
Weighted Standard Deviation: SDw = JEw^x^xJ2 I (E.w.-l)
CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Arkansas
100:
90
80
g 70
| 60^
I 50
0)
>
JS
| 30
o
20:
10:
0
0.0
1.0 2.0 3.0
Mercury Concentration in Fish (ppm)
4.0
3-21
-------
California
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
100
E 80
&
•5 60
HI
u>
TO
§ 40
20
Location Variables in Database
Number of records:
418
418
418
418
Water body
Location
Latitude
Longitude
Agency
3-22
-------
California
Data Source: State
Top Ten Fish Species
Common Name
Red shiner
Largemouth bass
Threespine stickleback
Fathead minnow
Arroyo chub
Percent
12
11
10
10
6
Common Name
Santa Ana sucker
Rainbow trout
Tui chub
Brown trout
Longjaw mudsucker
Percent
5
5
5
3
3
Fish Variables in Database
Number of records:
418 418 345
73 418
345
73
345
73
307 102
3-23
-------
California
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
80
a
s
•s 60
HI
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-24
-------
California
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Red shiner
Largemouth bass
Threespine stickleback
No. of
Samples
19
86
12
No. of
Fish
587
517
491
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.029
0.030
0.057
Max
(ppm)
0.157
1.800
0.329
Wt.
Mean
(ppm)b
0.061
0.291
0.156
Wt.
Median
(ppm)
0.057
0.190
0.114
Wt.
SDW<
0.034
0.304
0.098
cv
(%)"
54.88
104.60
62.58
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wtxi I E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
.w.(x.-xJ2 / (E.vc.-l)
Cumulative Distribution of Mercury Concentrations
for All Fish Species in California
100
90
80
g 70
I 60
I 50
| 40
| 30
O
20
10
0 -
0.0 0.2 0.4 0.6 0.8 1.0 1.2
Mercury Concentration in Fish (ppm)
1.4
1.6
1.8
3-25
-------
Connecticut
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
100
.E 80
a
s
ro
? 60
-------
Connecticut
Data Source: State
Top Four Fish Species"
Common Name
Largemouth bass
Yellow perch
Smallmouth bass
Bluegill sunfish
Percent
82
12
4
2
Only four species were identified in the data base.
Fish Variables in Database
Number of records:
631
631
631 631 0 631 631 0 631
3-27
-------
Connecticut
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
100
80
•g 60
01
O)
3
§ 40
£
20
Number of records:
o
631
618
Detect, limit Hg basis-Wet Hg basis - Dry Hg cone. Qualifier
3-28
-------
Connecticut
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Yellow perch
Smallmouth bass
No. of
Samples
507
77
22
No. of
Fish
507
77
22
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.032
0.033
0.234
Max
(ppm)
2.645
0.569
2.319
Wt.
Mean
(ppm)b
0.505
0.193
0.653
Wt.
Median
(ppm)
0.430
0.174
0.523
Wt.
SDW<
0.316
0.115
0.466
cv
(%)"
62.55
59.72
71.41
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(x.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Connecticut
100
90
_ 80
£
r 70
| 60
D.
I 50
I 40 i
O 30
20:
10:
0:
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-29
-------
Delaware
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
Number of records:
100
80
a
s
•5 60
HI
Q.
20
69
69
Water body Location Latitude Longitude Agency
3-30
-------
Delaware
Data Source: State
Top Ten Fish Species
Common Name
White sucker
Channel catfish
Yellow perch
Bluefish
Largemouth bass
Percent
27
10
9
7
7
Common Name
White perch
American eel
Common carp
Brown bullhead
Spot
Percent
6
5
5
4
4
Fish Variables in Database
Number of records:
69 69 35 34 69 68
68
60
3-31
-------
Delaware
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Mercury Variables in Database
Number of records:
69 69 0 69
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-32
-------
Delaware
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
White sucker
Channel catfish
Yellow perch
No. of
Samples
27
13
o
J
No. of
Fish
51
19
17
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.020
0.029
0.029
Max
(ppm)
0.264
0.133
0.086
Wt.
Mean
(ppm)b
0.060
0.050
0.049
Wt.
Median
(ppm)
0.050
0.042
0.040
Wt.
SDW<
0.050
0.033
0.025
cv
(%)"
83.11
66.44
49.90
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, -wpc, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(x.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Delaware
100 -
90-
80 -
8 60:
-------
District of Columbia
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
* i rdcates nurter of records
Location Variables in Database
100
.E 80
o
Q.
•5 60
8 40
Q.
20
Number of records:
75
75
75
75
75
Water body Location Latitude Longitude Agency
3-34
-------
District of Columbia
Data Source: State
Top Eight Fish Species3
Common Name
Common carp
Channel catfish
Largemouth bass
Brown bullhead
Percent
29
23
15
13
Common Name
American eel
Bluegill sunfish
Sunfish
Pumpkinseed sunfish
Percent
8
8
3
1
Only eight species were identified in the database.
Fish Variables in Database
Number of records:
75 75 75 0
75
3-35
-------
District of Columbia
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
100
1 80
a
•5 60
HI
u>
ra
§ 40
20
Number of records:
75
X X
Detect, limit Hg basis-Wet Hg basis - Dry Hg cone. Qualifier
3-36
-------
District of Columbia
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Common Carp
Channel catfish
Largemouth bass
No. of
Samples
22
17
11
No. of
Fish
22
17
11
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.042
0.055
0.037
Max
(ppm)
0.210
0.240
0.458
Wt.
Mean
(ppm)b
0.082
0.091
0.153
Wt.
Median
(ppm)
0.070
0.078
0.126
Wt.
SDW<
0.040
0.043
0.119
cv
(%)"
48.54
47.52
77.65
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wpc, / £,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
Weighted Standard Deviation: SDw = JEw^x^xJ2 I (E.w.-l)
CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in District of Columbia
100 -
90:
80 :
£ 70:
| 60:
>
5 40 :
I
30 :
20:
10
04
0.0 0.1 0.1 0.2 0.2 0.3 0.3 0.4
Mercury Concentration in Fish (ppm)
0.4
0.5
0.5
3-37
-------
Florida
Data Source: State and STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
100
80
a
s
•5 60
HI
Q.
20
Location Variables in Database
Number of records:
2829 2829
2156
2156
2804
Water body Location
Latitude Longitude Agency
3-38
-------
Florida
Data Source: State and STORE!
Top Ten Fish Species
Common Name
Largemouth bass
Spotted sea trout
Warmouth
Gray snapper
Common snook
Percent
71
3
3
3
3
Common Name
Florida gar
Cre vail e jack
Bluegill sunfish
Redear sunfish
Yellow bullhead
Percent
3
2
2
1
1
Fish Variables in Database
Number of records:
2829 2828 0
2476
2470 2491
337
3-39
-------
Florida
Data Source: State and STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
S
•,!^^,
\
Mercury (ppm):
" 0.5 to 1
A < = 0.5
% "" \
\ -4
*~ ii vSfc
Mercury Variables in Database
100
.E 80
•S 60
HI
O)
I
§ 40
20
Number of records:
2500
(\
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-40
-------
Florida
Data Source: State and STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Spotted sea trout
Warmouth
No. of
Samples
2000
92
84
No. of
Fish
2000
92
84
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.020
0.073
0.190
Max
(ppm)
4.360
1.800
1.700
Wt.
Mean
(ppm)b
0.645
0.677
0.778
Wt.
Median
(ppm)
0.550
0.695
0.700
Wt.
SDW<
0.466
0.381
0.356
cv
(%)"
72.28
56.32
45.78
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(x.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Florida
100-
90:
80:
£ 70:
§ 60:
^ 50^
0)
1 40:
I 30:
O :
20:
0.0
1.0 2.0 3.0
Mercury Concentration in Fish (ppm)
4.0
5.0
3-41
-------
Georgia
Data Source: State and STORE!
Records Analyzed by Year
Total Samples
Sampling Locations
100
80
a
s
•5 60
HI
Q.
20
Location Variables in Database
Number of records:
745
721
138
138
745
Water body Location
Latitude
Longitude
Agency
3-42
-------
Georgia
Data Source: State and STORE!
Top Ten Fish Species
Common Name
Largemouth bass
Channel catfish
Black crappie
Hybrid bass
Common carp
Percent
29
20
6
5
4
Common Name
Flathead catfish
Spotted sucker
Bluegill sunfish
Redbreast sunfish
Redear sunfish
Percent
4
3
3
2
2
Fish Variables in Database
Number of records:
745 694 647
45
692
598 607
598 607
643
49
53
3-43
-------
Georgia
Data Source: State and STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
^ ^ r
Mercury Variables in Database
100
.E 80
o
Q.
5
•5
60
8 40
I
20
Number of records:
745
r \
I
Detect, limit Hg basis -Wet Hg basis-Dry Hgconc. Qualifier
3-44
-------
Georgia
Data Source: State and STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Channel catfish
Black crappie
No. of
Samples
206
136
43
No. of
Fish
968
658
210
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.010
0.010
0.010
Max
(ppm)
2.286
1.143
0.300
Wt.
Mean
(ppm)b
0.274
0.084
0.029
Wt.
Median
(ppm)
0.199
0.060
0.020
Wt.
SDW<
0.306
0.140
0.040
cv
(%)"
111.88
166.62
134.46
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(x.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Georgia
100:
90:
80:
Q)
B 60 -
-------
Illinois
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Number of records:
105
105
105
105
105
Water body Location
Latitude Longitude Agency
3-46
-------
Illinois
Data Source: STORE!
Top Ten Fish Species
Common Name
Largemouth bass
Bluegill sunfish
White crappie
Smallmouth bass
Walleye
Percent
67
7
5
5
5
Common Name
White bass
Lake trout
Brown trout
Channel catfish
Chinook salmon
Percent
3
2
2
1
1
Fish Variables in Database
Number of records:
105 105 96 8 104 89
96 8 104 1
3-47
-------
Illinois
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
*
Mercury (ppm):
" 0.5 to 1
A < = 0.5
-/
Mercury Variables in Database
100
1 80
a
•5 60
HI
u>
TO
§ 40
20
Number of records:
105
Detect, limit Hg basis-Wet Hg basis - Dry Hg cone. Qualifier
3-48
-------
Illinois
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Bluegill sunfish
White crappie
No. of
Samples
71
6
5
No. of
Fish
305
30
24
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.010
0.010
0.040
Max
(ppm)
0.880
0.100
0.150
wt.
Mean
(ppm)b
0.180
0.058
0.075
Wt.
Median
(ppm)
0.120
0.060
0.060
Wt.
SDW<
0.163
0.043
0.041
cv
(%)"
90.61
72.88
54.20
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(x.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Illinois
100:
90 :
80:
£ :
•E 60:
CD
O
o! 5° ~-
-------
Indiana
Data Source: State
Records Analyzed by Year
Total Samples
Sampling Locations
• •* • . . .
- V" '
" • .'
.• • •
Location Variables in Database
100
c 80
o
Q.
BO
40
-------
Indiana
Data Source: State
Top Ten Fish Species
Common Name
Common carp
Creek chub
White sucker
Black redhorse
Rock bass
Percent
25
7
7
7
7
Common Name
Longear sunfish
Channel catfish
Smallmouth bass
Largemouth bass
Spotted bass
Percent
6
6
5
3
2
Fish Variables in Database
Number of records:
505 505 393 112 505 393 112 394 111 403 101 0
3-51
-------
Indiana
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
JLr-
Mercury (ppm):
" 0.5 to 1
A < = 0.5
100
a
.E 80
•a
•5
0)
O)
60
40
20
Mercury Variables in Database
Number of records:
505 505 0 50
Detect.limit Hgbasis-Wet Hg basis-Dry Hgconc.
Qualifier
3-52
-------
Indiana
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Common carp
Creek chub
White sucker
No. of
Samples
154
15
25
No. of
Fish
506
144
143
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.010
0.029
0.030
Max
(ppm)
1.000
0.143
0.240
Wt.
Mean
(ppm)"
0.166
0.094
0.137
Wt.
Median
(ppm)
0.145
0.100
0.120
Wt.
SDW<
0.125
0.034
0.057
cv
(%)"
75.25
36.00
41.38
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
Weighted Standard Deviation: SDw = »/E.w.(jc.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Indiana
100 -
90:
80 -.
£ 70^
§ 60:
-------
Iowa
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
1 80
a
•5 60
HI
u>
ra
§ 40
20
Number of records:
132
132
132
132
132
Water body Location
Latitude Longitude Agency
3-54
-------
Iowa
Data Source: STORE!
Top Nine Fish Species3 b
Common Name
Channel catfish
Common carp
Largemouth bass
White crappie
Northern pike
Percent
59
27
7
3
1
Common Name
Smallmouth bass
Walleye
Yellow perch
White bass
Percent
1
1
1
1
a Species identified as "Unknown" were excluded from this analysis.
b Only nine species were identified in the database.
100
o 80
I BO
40
20
Fish Variables in Database
Number of records:
132 130 130 0 130 0 0 00 103 27 2
3-55
-------
Iowa
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
\
Mercury (ppm):
" 0.5 to 1
A < = 0.5
\r
Mercury Variables in Database
Number of records:
100
I 80
o
Q.
•s 60
HI
Q.
20
x:
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-56
-------
Iowa
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Channel catfish
Common carp
Largemouth bass
No. of
Samples
74
37
9
No. of
Fish
323
145
38
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.030
0.014
0.080
Max
(ppm)
0.410
0.486
0.480
Wt.
Mean
(ppm)b
0.104
0.215
0.189
Wt.
Median
(ppm)
0.090
0.171
0.150
Wt.
SDW<
0.063
0.132
0.116
cv
(%)"
60.64
61.31
61.35
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, -wxt / X),. w,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = t/E.W (x ~X )2 / (E.W -1)
w v z ' z' w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Iowa
0.1
0.1
0.2 0.2 0.3 0.3 0.4
Mercury Concentration in Fish (ppm)
0.4
0.5
0.5
3-57
-------
Kansas
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
• *
•
I
»• fc • «
\ ' • '" *
. - .'
100
.E 80
60
HI
O)
I
§ 40
20
Location Variables in Database
Number of records:
193 193 193 193
193
Water body Location
Latitude Longitude Agency
3-58
-------
Kansas
Data Source: STORE!
Top Ten Fish Species"
Common Name
Common carp
Channel catfish
Black bullhead
White sucker
River carpsucker
Percent
76
8
4
3
3
Common Name
Smallmouth buffalo
Yellow bullhead
White bass
White crappie
Shorthead redhorse
Percent
1
1
1
1
1
Species identified as "Unknown" and "Mixed species" were excluded from this analysis.
Fish Variables in Database
Number of records:
193 174 169
174
44
130
19
3-59
-------
Kansas
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
. • t
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
0 193 0 1<
100
to
= 80
a
s
TO
"5 60
HI
O)
1
S 40
b
Q.
20
n
-
-
-
/
X
1
Detect, limit Hg basis -Wet Hg basis - Dry Hg cone. Qualifier
3-60
-------
Kansas
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Common carp
Channel catfish
Black bullhead
No. of
Samples
133
12
8
No. of
Fish
556
56
31
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.014
0.029
0.090
Max
(ppm)
0.386
0.314
0.271
Wt.
Mean
(ppm)b
0.167
0.125
0.168
Wt.
Median
(ppm)
0.157
0.140
0.150
Wt.
SDW<
0.079
0.083
0.061
cv
(%)"
47.06
66.71
36.48
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, w^r, / E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.w.(x.-xw)2 / (E.w.-l)
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Kansas
100-
90 -.
80-
l 70 :.
ro 40 ~.
20-
10 -.
0-
0.0 0.1 0.1 0.2 0.2 0.3 0.3
Mercury Concentration in Fish (ppm)
0.4
0.4
3-61
-------
Kentucky
Data Source: State andSTORET
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
Number of records:
100
E 80
a
s
ra
2 60
HI
Q.
20
248
47
X XI
Water body Location
47
248
Latitude Longitude Agency
3-62
-------
Kentucky
Data Source: State and STORE!
Top Ten Fish Species
Common Name
Shad
Alewife
Bluegill sunfish
Largemouth bass
Skipjack herring
Percent
46
14
9
9
6
Common Name
Channel catfish
Walleye
Common carp
Catfish
River redhorse
Percent
4
3
2
1
1
Fish Variables in Database
Number of records:
248 210 107 129 238 76 167 71 170
128
89 31
100
'c
'g. 80
s
re
•a
•5 so
HI
O)
I 40
u
0>
0.
20
n
/
-
-
1
/
1
3-63
-------
Kentucky
Data Source: State and STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
100
1 80
a
•5 60
HI
u>
TO
§ 40
20
Number of records:
69
Detect, limit Hg basis-Wet Hg basis - Dry Hg cone. Qualifier
3-64
-------
Kentucky
Data Source: State and STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Shad
Alewife
Bluegill sunfish
No. of
Samples
16
17
41
No. of
Fish
608
182
125
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.009
0.300
0.029
Max
(ppm)
0.386
3.429
0.825
Wt.
Mean
(ppm)b
0.104
0.522
0.236
Wt.
Median
(ppm)
0.167
0.386
0.190
Wt.
SDW<
0.076
0.422
0.180
cv
(%)"
72.75
80.85
76.38
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = £,. wpc, I E,w,, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Kentucky
100-
90 -.
80:
g 70 -.
£ 50 -.
-------
Louisiana
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Number of records:
1093
1093
1088
1088
1093
Water body Location
Latitude Longitude Agency
3-66
-------
Louisiana
Data Source: State
Top Ten Fish Species
Common Name
Largemouth bass
Channel catfish
White crappie
Bowfm
Black crappie
Percent
41
7
7
4
4
Common Name
Redear sunfish
Bluegill sunfish
Blue catfish
Bigmouth buffalo
Common carp
Percent
4
4
4
3
3
Fish Variables in Database
Number of records:
1093 1093 886 207 207 525 204 884 207 1093 0 0
3-67
-------
Louisiana
Data Source: State
^
.
•t, *
1, t'
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
100
.E 80
o
Q.
•s 60
40
-------
Louisiana
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Channel catfish
White crappie
No. of
Samples
452
76
76
No. of
Fish
452
76
76
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.001
0.001
0.001
Max
(ppm)
1.883
0.732
1.113
Wt.
Mean
(ppm)b
0.391
0.111
0.240
Wt.
Median
(ppm)
0.332
0.060
0.165
Wt.
SDW<
0.306
0.143
0.237
CV
(%)"
78.32
128.19
98.84
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wpc, I E,w,, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Louisiana
100 :
90:
80:
' 70 :
60:
50:
(D
CL
| 40 i
3 30
20:
10 :
0:
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4
Mercury Concentration in Fish (ppm)
1.6
2.0
3-69
-------
Maine
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
80
a
s
•5 60
HI
Q.
20
Number of records:
354
354
354
354
Water body Location
Latitude Longitude
Agency
3-70
-------
Maine
Data Source: State
Top Ten Fish Species
Common Name
White sucker
Brook trout
Largemouth bass
Smallmouth bass
Landlocked Atlantic salmon
Percent
34
15
9
9
7
Common Name
Yellow perch
White perch
Chain pickerel
Brown trout
Lake trout
Percent
7
6
4
4
4
Fish Variables in Database
Number of records:
354 354 354
354 354
354
120 234
3-71
-------
Maine
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
.E 80
•S 60
HI
O)
I
§ 40
20
X
Detect, limit Hg basis -Wet Hg basis - Dry Hg cone.
Qualifier
3-72
-------
Maine
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
White sucker
Brook trout
Largemouth bass
No. of
Samples
110
59
30
No. of
Fish
536
228
137
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.003
0.025
0.071
Max
(ppm)
1.714
1.343
1.343
Wt.
Mean
(ppm)b
0.338
0.459
0.634
Wt.
Median
(ppm)
0.257
0.410
0.600
Wt.
SDW<
0.272
0.269
0.242
CV
(%)"
80.52
58.54
38.19
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wpc, / £,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
Weighted Standard Deviation: SDw = JEw^x^xJ2 I (E.w.-l)
CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Maine
100:
90
80 :
g 70:
§ 60:
(u
°- 50 :
CD
I 40:
I 3(H
O
20 :
10 :
o-
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-73
-------
Maryland
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
Number of records:
0 0 316 316
100
317
to
= 80
a
s
ra
2 60
o
HI
O)
| 40
b
Q.
20
n
-
-
-
_
_
Water body Location
Latitude Longitude
Agency
3-74
-------
Maryland
Data Source: State
Top Ten Fish Species
Common Name
Channel catfish
White perch
Striped bass
White sucker
Brown bullhead
Percent
20
17
12
11
7
Common Name
Largemouth bass
Smallmouth bass
White catfish
Common carp
Brown trout
Percent
6
6
5
4
O
Fish Variables in Database
Number of records:
317 317 141 176 317 1 174
228 87
3-75
-------
Maryland
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
./v
-~i£
i *
\ I
X^ ^
*£..-
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
100
I 80
o
Q.
•s 60
HI
Q.
20
Number of records:
317
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-76
-------
Maryland
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Channel catfish
White perch
Striped bass
No. of
Samples
66
28
95
No. of
Fish
157
135
95
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.006
0.013
0.003
Max
(ppm)
0.256
0.134
0.177
Wt.
Mean
(ppm)b
0.033
0.038
0.036
Wt.
Median
(ppm)
0.024
0.027
0.023
Wt.
SDW<
0.031
0.026
0.035
cv
(%)"
95.24
66.91
98.93
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w^r, / X),.vf,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = i/E.W (x ~X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
100
90
80
g 70
§ 60
fe
s50
| 40
1 30
20
10
0
0.0
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Maryland
0.1
0.1 0.2 0.2
Mercury Concentration in Fish (ppm)
0.3
0.3
3-77
-------
Massachusetts
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
-^
Latitude and Longitude Data Not Available
100
V)
c 80
1
re
IS
I 60
20
Location Variables in Database
Number of records:
550 550 0 0
550
Water body Location
Latitude
Longitude Agency
3-78
-------
Massachusetts
Data Source: State
Top Five Fish Species"
Common Name
Yellow perch
Brown bullhead
Largemouth bass
Yellow bullhead
Smallmouth bass
Percent
36
31
28
3
3
Only five species were identified in the database.
100
1 80
•5 60
40
20
Fish Variables in Database
Number of records:
0 550 0 550 550 0 550
550 550 0 0
.
X «X N
* ^e ^°
3-79
-------
Massachusetts
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
Mercury Variables in Database
Number of records:
100
I 80
&
ro
IS
2 60
01
O)
ro
§ 40
20
550
550
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-80
-------
Massachusetts
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Yellow perch
Brown bullhead
Largemouth bass
No. of
Samples
198
169
152
No. of
Fish
198
169
152
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.010
0.010
0.045
Max
(ppm)
0.752
0.794
1.100
Wt.
Mean
(ppm)b
0.306
0.141
0.399
Wt.
Median
(ppm)
0.272
0.108
0.334
Wt.
SDW<
0.155
0.106
0.233
CV
(%)"
50.62
75.55
58.38
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wlxi I E,w,, where w is the weight (# offish in composite sample) and x is the average
mercury concentration (ppm) in the composite sample.
Weighted Standard Deviation: SDw = JEw^x^xJ2 I (E.w.-l)
CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Massachusetts
100
90
80
I 70:
> 60:
- 50:
J 40:
!
30
20:
10
o-\
O
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
Mercury Concentration in Fish (ppm)
0.9
1.0
1.1
3-81
-------
Michigan
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
ToMFish
Latitude and Longitude Data Not Available
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Location Variables in Database
Number of records:
4218 4218
0
0
Water body Location
Latitude Longitude
Agency
3-82
-------
Michigan
Data Source: State
Top Ten Fish Species
Common Name
Channel catfish
Common carp
Walleye
Northern pike
Largemouth bass
Percent
19
18
15
8
7
Common Name
Lake trout
Yellow perch
White sucker
Smallmouth bass
Lake whitefish
Percent
5
4
3
2
2
Fish Variables in Database
Number of records:
4218 4213 150 4068 4217 149 4059 149 4017 3152 1047 19
X
3-83
-------
Michigan
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
Mercury Variables in Database
Number of records:
100
.E 80
o
Q.
•5 60
8 40
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-84
-------
Michigan
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Channel catfish
Common carp
Walleye
No. of
Samples
190
908
723
No. of
Fish
964
934
763
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.014
0.010
0.030
Max
(ppm)
0.710
0.814
1.740
Wt.
Mean
(ppm)b
0.047
0.181
0.375
Wt.
Median
(ppm)
0.029
0.160
0.290
Wt.
SDW<
0.062
0.107
0.272
cv
(%)"
131.91
59.20
72.53
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w^r, / X),.vf,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = i/E.W (x ~X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Michigan
100
90
80
70
60
50
>
|5
=3
O
20:
10:
0:
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-85
-------
Minnesota
Data Source: State
Records Analyzed by Year
Total Samples
Sampling Locations
100
.E 80
•5 60
HI
6)
I
§ 40
20
Location Variables in Database
Number of records:
5488 5142
1317
1317
X X
s_
rim
Water body Location
Latitude Longitude
Agency
3-86
-------
Minnesota
Data Source: State
Top Ten Fish Species
Common Name
Walleye
Northern pike
White sucker
Bluegill sunfish
Yellow perch
Percent
26
23
9
8
7
Common Name
Common carp
Black crappie
Lake trout
Cisco (lake herring)
Smallmouth bass
Percent
6
5
2
2
1
Fish Variables in Database
Number of records:
5488 5475 3534 1954 5488 3534 1954 3525 1953 5414 44 30
3-87
-------
Minnesota
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
to
I 80
o
Q.
1
Z 60
-------
Minnesota
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Walleye
Northern pike
White sucker
No. of
Samples
1677
1562
427
No. of
Fish
5636
5019
1987
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.010
0.010
0.010
Max
(ppm)
2.900
2.500
0.680
Wt.
Mean
(ppm)b
0.325
0.304
0.103
Wt.
Median
(ppm)
0.260
0.250
0.075
Wt.
SDW<
0.253
0.219
0.090
cv
(%)"
77.97
71.93
86.99
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = £,. wpc, I E,w,, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Minnesota
100
90
_ 80
£
r 70
| 60
D.
I 5°
i 40
O 30
20
0 -1
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-89
-------
Mississippi
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
.E 80
o
Q.
•5 60
§ 40
-------
Mississippi
Data Source: State
Top Ten Fish Species
Common Name
Largemouth bass
Channel catfish
Bass
Flathead catfish
Spotted bass
Percent
54
14
6
6
5
Common Name
Smallmouth buffalo
Buffalo
White crappie
Common carp
Bigmouth buffalo
Percent
3
1
1
1
1
Fish Variables in Database
Number of records:
378 378 285 93 378
287 91
11
360
3-91
-------
Mississippi
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
r
Mercury Variables in Database
Number of records:
100
.E 80
o
Q.
•s 60
40
-------
Mississippi
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Channel catfish
Bass
No. of
Samples
203
43
21
No. of
Fish
606
157
72
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.090
0.040
0.370
Max
(ppm)
2.630
2.100
2.400
Wt.
Mean
(ppm)b
0.651
0.274
0.913
Wt.
Median
(ppm)
0.580
0.210
0.890
Wt.
SDW<
0.393
0.299
0.417
cv
(%)"
60.31
109.24
45.68
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, -wxt / X),. w,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = t/E.W (x ~X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Mississippi
100
90
_ 80
r 70
QJ
*— DU
Qj
CL
g 50
I 40
O 30
20-
0-
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-93
-------
Missouri
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Latitude and Longitude Data Not Available
Location Variables in Database
Number of records:
0 403
403
•inn
1 UU
to
.E 80
3
TO
2 60
HI
O)
S
§ 40
20
n
/ /
-
-
—
I
1
X ^
1 1
1
Waterbody Location
Latitude Longitude Agency
3-94
-------
Missouri
Data Source: State
Top Ten Fish Species
Common Name
Common carp
Channel catfish
Largemouth bass
Shorthead redhorse
Sunfish
Percent
59
10
5
4
O
Common Name
Black redhorse
Golden redhorse
Paddlefish
Sucker
Walleye
Percent
3
3
3
2
1
Fish Variables in Database
Number of records:
403 403 225 77 302
181 52 317 84
3-95
-------
Missouri
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
100
E 80
TO
2 60
HI
O)
I
§ 40
20
Mercury Variables in Database
Number of records:
0 403 0 403
s_
r
Detect, limit Hg basis -Wet Hg basis - Dry Hg cone.
Qualifier
3-96
-------
Missouri
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Common carp
Channel catfish
Largemouth bass
No. of
Samples
184
50
24
No. of
Fish
1224
198
106
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.002
0.002
0.002
Max
(ppm)
0.454
0.350
0.608
Wt.
Mean
(ppm)b
0.128
0.052
0.257
Wt.
Median
(ppm)
0.125
0.040
0.230
Wt.
SDW<
0.061
0.055
0.151
cv
(%)"
47.54
106.63
58.73
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, -wxt / X),. w,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = t/E.W (x ~X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Missouri
100:
90
80:
g 7Q:
| 60:
f 50:
I 40 H
O
30:
20:
10:
0:
0.0 0.1 0.2 0.3 0.4 0.5 0.6
Mercury Concentration in Fish (ppm)
0.7
0.8
0.9
3-97
-------
Nebraska
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
100
1 80
a
•5 60
HI
u>
ra
§ 40
20
Location Variables in Database
Number of records:
271
271
271
271
271
Water body Location
Latitude Longitude Agency
3-98
-------
Nebraska
Data Source: STORE!
Top Ten Fish Species
Common Name
Common carp
Channel catfish
Largemouth bass
Walleye
White sucker
Percent
44
23
18
5
3
Common Name
Black bullhead
Northern pike
River carpsucker
Hybrid bass
Flathead catfish
Percent
2
1
1
1
1
Fish Variables in Database
Number of records:
271 271 255 12 267 0 0 00
200 67
n
0^
<&•*
3-99
-------
Nebraska
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
*
. /*J
•**\
At, A A* ^
Mercury (ppm):
" 0.5 to 1
A < = 0.5
100
80
a
•5 60
HI
Q.
20
Mercury Variables in Database
Number of records:
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-100
-------
Nebraska
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Common carp
Channel catfish
Largemouth bass
No. of
Samples
121
59
44
No. of
Fish
449
238
182
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.030
0.001
0.080
Max
(ppm)
0.600
0.643
0.920
Wt.
Mean
(ppm)b
0.168
0.109
0.343
Wt.
Median
(ppm)
0.143
0.080
0.310
Wt.
SDW<
0.095
0.102
0.203
cv
(%)"
57.24
93.58
59.12
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = £,. wpc, I E,w,, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Nebraska
100-
90
80
E 7°~
§ 6°^
£ 50-
1
o
30-
20-
10
OH
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7
Mercury Concentration in Fish (ppm)
0.8
0.9
1.0
3-101
-------
New Hampshire
Data Source: State
Records Analyzed by Year
Total Samples
Sampling Locations
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Location Variables in Database
Number of records:
177 177 177 177
Water body Location
Latitude Longitude
Agency
3-102
-------
New Hampshire
Data Source: State
Top Ten Fish Species
Common Name
Largemouth bass
Yellow perch
Brook trout
Chain pickerel
Brown bullhead
Percent
18
18
14
12
11
Common Name
Smallmouth bass
Lake trout
White perch
Brown trout
Landlocked Atlantic salmon
Percent
7
5
4
3
3
Fish Variables in Database
Number of records:
177 177 12 165 175 7
164
158 175
2_
X
/ —
7
/
X -X X* .°*"
^ X ^ 0^
X '
3-103
-------
New Hampshire
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
* «-
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
.E 80
o
Q.
•s 60
40
-------
New Hampshire
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth
bass
Yellow
perch
Brook trout
No. of
Samples
35
29
15
No. of
Fish
35
35
28
Mercury Statistics Weighted by No. of Fish in Sample"
Min
(ppm)
0.210
0.110
0.100
Max
(ppm)
1.400
0.640
0.610
Wt.
Mean
(ppm)b
0.573
0.346
0.160
Wt.
Median
(ppm)
0.460
0.350
0.130
Wt.
SDW<
0.321
0.136
0.125
cv
(%)d
56.02
39.32
78.04
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean Ow = ', nyc,- / ' , wt, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: $Dw ' J ' z-W.(jC.&xJ2 / ( ' r-W.&l)
d CV = (SDW/0W)*100
3-105
-------
New Jersey
Data Source: STORE!
Records Analyzed by Year
Total Samples
Sampling Locations
Latitude and Longitude Data Not Available
Location Variables in Database
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Number of records:
373 0
373
Water body Location
Latitude Longitude
Agency
3-106
-------
New Jersey
Data Source: STORE!
Top Ten Fish Species
Common Name
Largemouth bass
Chain pickerel
Brown bullhead
Smallmouth bass
Black crappie
Percent
46
19
7
6
5
Common Name
Channel catfish
White catfish
Yellow bullhead
Hybrid bass
Lake trout
Percent
4
3
2
2
2
Fish Variables in Database
Number of records:
373 373 0 373 373 373
372
373
3-107
-------
New Jersey
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
Mercury Variables in Database
Number of records:
100
.E 80
o
Q.
•5 60
8 40
Q.
20
X A
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-108
-------
New Jersey
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Chain pickerel
Brown bullhead
No. of
Samples
173
72
26
No. of
Fish
173
72
26
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.030
0.090
0.020
Max
(ppm)
8.940
2.810
0.470
Wt.
Mean
(ppm)b
0.664
0.743
0.105
Wt.
Median
(ppm)
0.370
0.505
0.060
Wt.
SDW<
1.003
0.621
0.106
cv
(%)"
150.95
83.68
101.60
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, -wxt IX),. w,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = t/E.W (x ~X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in New Jersey
100-
90^
80^
I 70--
60-
50-
o
OJ
D.
-| 40 -
E
O
30-
20-
-\o-
0-
0.0 1.0 2.0 3.0 4.0 5.0 6.0
Mercury Concentration in Fish (ppm)
7.0
8.0
9.0
3-109
-------
New Mexico
Data Source: State
Records Analyzed by Year
Total Samples
Sampling Locations
Latitude and Longitude Data Not Available
Location Variables in Database
100
80
a
s
•5 60
HI
Q.
20
Number of records:
467
467
467
Water body
Location
Latitude
Longitude
Agency
3-110
-------
New Mexico
Data Source: State
Top Ten Fish Species
Common Name
Channel catfish
Walleye
Rainbow trout
White sucker
Largemouth bass
Percent
17
14
10
9
7
Common Name
White bass
Brook trout
Kokanee salmon
Black bullhead
Bluegill sunfish
Percent
7
4
4
4
3
Number of records:
467 467 0
Fish Variables in Database
467 467 0 466 0 446 467
3-111
-------
New Mexico
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
Mercury Variables in Database
Number of records:
100
80
a
s
TO
•o
• 60
HI
Q.
20
467 467
467 117
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-112
-------
New Mexico
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Channel
catfish
Walleye
Rainbow
trout
No. of
Samples
78
67
45
No. of
Fish
78
67
45
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.100
0.070
0.100
Max
(ppm)
1.800
3.000
0.200
wt.
Mean
(ppm)b
0.297
0.875
0.107
Wt.
Median
(ppm)
0.200
0.710
0.100
Wt.
SDW<
0.276
0.663
0.021
cv
(%)"
93.02
75.76
19.28
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w^r, / £, w,, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SDw =
CV = (SDW / xw) * 100
I
Cumulative Distribution of Mercury Concentrations
for All Fish Species in New Mexico
100:
90:
80:
g 70:
1 6°'
I 50
i 40 ~-
1 30:
20:
10:
0:
O
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-113
-------
New York
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
* irdcates nurterof records
Location Variables in Database
100
1 80
a
•5 60
HI
u>
ra
§ 40
20
Number of records:
993
993
881
881
Water body Location Latitude Longitude
Agency
3-114
-------
New York
Data Source: State
Top Ten Fish Species
Common Name
Yellow perch
Lake trout
Largemouth bass
Smallmouth bass
Rock bass
Percent
50
11
5
4
4
Common Name
Brown trout
American eel
Northern pike
Brown bullhead
Common carp
Percent
4
3
3
3
2
Fish Variables in Database
Number of records:
993 993 0 632 632 361 632 0 983 535 0 458
3-115
-------
New York
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
80
a
s
TO
•o
• 60
HI
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-116
-------
New York
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Yellow
perch
Lake trout
Largemouth
bass
No. of
Samples
490
108
53
No. of
Fish
490
108
53
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.010
0.010
0.050
Max
(ppm)
2.140
0.860
0.950
Wt.
Mean
(ppm)b
0.477
0.162
0.462
Wt.
Median
(ppm)
0.380
0.120
0.430
Wt.
SDW<
0.346
0.138
0.253
CV
(%)"
72.49
85.36
54.67
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wpc, I E,.vf,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in New York
100
90
80
r 70
\ 60
)
i 50^
! 30^
20-
o-
0.0
1.0 2.0 3.0
Mercury Concentration in Fish (ppm)
4.0
3-117
-------
North Carolina
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
100
1 80
a
•5 60
HI
u>
ra
§ 40
20
Location Variables in Database
Number of records:
2809 2809 1794 1794
2809
Water body Location
Latitude Longitude
Agency
3-118
-------
North Carolina
Data Source: State
Top Ten Fish Species
Common Name
Largemouth bass
Bluegill sunfish
Bowfm
Redbreast sunfish
Black crappie
Percent
34
15
8
7
4
Common Name
Channel catfish
White catfish
Redhorse sucker
White perch
Common carp
Percent
3
3
2
2
2
Fish Variables in Database
Number of records:
2809 2809 415 2394 2809 408 2387 414 2390 2708 100 1
3-119
-------
North Carolina
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
E 80
TO
2 60
HI
O)
I
§ 40
20
Detect, limit Hg basis -Wet Hg basis - Dry Hg cone. Qualifier
3-120
-------
North Carolina
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth bass
Bluegill sunfish
Bowfin
No. of
Samples
1327
304
349
No. of
Fish
1569
699
357
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.020
0.020
0.110
Max
(ppm)
3.600
0.780
5.700
Wt.
Mean
(ppm)b
0.532
0.186
0.944
Wt.
Median
(ppm)
0.390
0.160
0.760
Wt.
SDW<
0.504
0.130
0.692
cv
(%)"
94.76
69.79
73.27
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = £,. wpc, I E,w,, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in North Carolina
100
90
80
Cp" / 0
o"-
|60;
-------
Ohio
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Latitude and Longitude Data Not Available
Location Variables in Database
100
.E 80
•5 60
HI
u>
ra
§ 40
20
Number of records:
1531
1531
1531
X A
Water body Location
Latitude
Longitude
Agency
3-122
-------
Ohio
Data Source: State
Top Ten Fish Species
Common Name
Common carp
Smallmouth bass
Channel catfish
Rock bass
Largemouth bass
Percent
17
15
12
10
7
Common Name
White bass
Sauger
Freshwater drum
White crappie
Hybrid bass
Percent
5
4
4
3
3
Fish Variables in Database
Number of records:
1531 1531 1311 219 1502 0
1349 176 6
100
'» 80
T3
•S 60
40
20
00>
f?
X° «f «** .** X6 .X .^
xV
4\^
^
^
^
3-123
-------
Ohio
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
Mercury Variables in Database
Number of records:
100
80
a
s
TO
•o
• 60
HI
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-124
-------
Ohio
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Common
carp
Smallmouth
bass
Channel
catfish
No. of
Samples
234
236
205
No. of
Fish
816
716
574
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.013
0.022
0.018
Max
(ppm)
1.097
0.743
1.040
Wt.
Mean
(ppm)b
0.124
0.173
0.118
Wt.
Median
(ppm)
0.106
0.158
0.098
Wt.
SDW<
0.107
0.096
0.103
cv
(%)"
86.12
55.19
87.25
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w/Xj I X),-vf,-, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = Ew/X.-Jt J2 / (E^.-
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Ohio
100
90 ~\
80
CL
-------
Oklahoma
Data Source: State and STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
100
.E 80
TO
•5 60
HI
O)
I
§ 40
20
Location Variables in Database
Number of records:
552 552 509 509
312
Water body Location
Latitude Longitude
Agency
3-126
-------
Oklahoma
Data Source: State and STORE!
Top Ten Fish Species
Common Name
Gizzard shad
Channel catfish
Common carp
River carp sucker
Largemouth bass
Percent
15
11
10
8
8
Common Name
White bass
White crappie
Smallmouth buffalo
Freshwater drum
Plains killifish
Percent
7
5
5
4
3
Fish Variables in Database
Number of records:
552 552 550
547 549
549
532 18
3-127
-------
Oklahoma
Data Source: State and STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
^v '
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
80
a
s
•5 60
HI
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-128
-------
Oklahoma
Data Source: State and STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Gizzard
shad
Channel
catfish
Common
carp
No. of
Samples
76
67
56
No. of
Fish
431
324
277
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.100
0.100
0.100
Max
(ppm)
0.660
0.640
0.280
Wt.
Mean
(ppm)b
0.117
0.193
0.133
Wt.
Median
(ppm)
0.100
0.140
0.100
Wt.
SDW<
0.064
0.126
0.046
cv
(%)"
54.58
65.26
34.35
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w/Xj I X),-vf,-, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = Ew/X.-Jt J2 / (E^.-
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Oklahoma
100 -
90 -_
80 -.
$ 40
jo
1 30 ~.
10 T
o -
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-129
-------
Oregon
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Latitude and Longitude Data Not Available
Location Variables in Database
100
.E 80
o
Q.
•5 60
| 40
-------
Oregon
Data Source: State
Top Ten Fish Species
Common Name
Sockeye salmon
Largemouth bass
Smallmouth bass
Sucker
Common carp
Percent
13
13
10
7
6
Common Name
Rainbow trout
Black crappie
Brown trout
Chiselmouth
Bullhead catfish
Percent
6
5
5
5
4
Fish Variables in Database
Number of records:
605 605 67 538 605 36 494 35 477 503 63 39
100
re
re
T3
•5 so
HI
ro
3
g 40
u
0)
0.
20
X
-------
Oregon
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
Mercury Variables in Database
Number of records:
100
.E 80
o
Q.
•5 60
8 40
Q.
20
605 31
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
-------
Oregon
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Sockeye
salmon
Largemouth
bass
Smallmouth
bass
No. of
Samples
42
116
71
No. of
Fish
124
120
95
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.040
0.030
0.060
Max
(ppm)
1.390
0.980
2.540
Wt.
Mean
(ppm)b
0.186
0.369
0.366
Wt.
Median
(ppm)
0.043
0.340
0.310
Wt.
SDW<
0.352
0.210
0.325
cv
(%)"
189.41
56.72
88.96
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w/Xj I X),-vf,-, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = Ew/X.-Jt J2 / (E^.-
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Oregon
100 -
90^
80^
1 60
o
-------
Pennsylvania
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
r • • • *
• / . f
• i • t »• «
100
80
a
•5 60
HI
Q.
20
Location Variables in Database
Number of records:
313
313
313
313
313
Water body Location
Latitude Longitude Agency
-------
Pennsylvania
Data Source: STORE!
Top Ten Fish Species"
Common Name
Smallmouth bass
Largemouth bass
Brown trout
Common carp
Walleye
Percent
18
13
12
9
8
Common Name
Channel catfish
Rock bass
Yellow perch
White sucker
Rainbow trout
Percent
8
6
6
4
2
Species identified as "Unknown" were excluded from this analysis.
Fish Variables in Database
Number of records:
313 313 238 25 263
251 1
-------
Pennsylvania
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
80
a
s
TO
•o
• 60
HI
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
-------
Pennsylvania
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Smallmouth
bass
Largemouth
bass
Brown trout
No. of
Samples
50
32
27
No. of
Fish
191
139
133
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.070
0090
0.020
Max
(ppm)
0.580
0.750
0.560
Wt.
Mean
(ppm)b
0.259
0.293
0.120
Wt.
Median
(ppm)
0.230
0.250
0.100
Wt.
SDW<
0.129
0.178
0.102
cv
(%)"
49.76
60.70
85.02
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w^r, / X),.vc,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = i/E.W (x ~X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Pennsylvania
100 -
90
80 -
70:
o
I 50 ^
$ 40 -\
jo
O
30 ~
20 -.
10 :
0:
0.0 0.2 0.4 0.6 0.8 1.0 1.2
Mercury Concentration in Fish (ppm)
1.4
1.6
1.8
-------
South Carolina
Data Source: State and STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
.E 80
o
Q.
•5 60
§ 40
-------
South Carolina
Data Source: State and STORE!
Top Ten Fish Species
Common Name
Largemouth bass
Bowfm
Channel catfish
Striped bass
Bluegill sunfish
Percent
62
11
5
3
2
Common Name
Red drum
Redear sunfish
Bluntnose minnow
Blue catfish
Black crappie
Percent
2
2
2
2
1
Fish Variables in Database
Number of records:
675 675 30 635 665 0 273
273 664 24
-------
South Carolina
Data Source: State and STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
.E 80
o
Q.
•5 60
40
-------
South Carolina
Data Source: State and STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largemouth
bass
Bowfin
Channel
catfish
No. of
Samples
403
87
32
No. of
Fish
505
87
42
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.230
0.250
0.250
Max
(ppm)
3.330
7.000
1.610
Wt.
Mean
(ppm)b
0.994
1.348
0.345
Wt.
Median
(ppm)
0.920
1.060
0.250
Wt.
SDW<
0.711
1.122
0.304
cv
(%)"
71.45
83.21
88.18
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = £,. wpc, I E,.vf,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw =
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in South Carolina
100 -
90 :
80 T
g 70
§ 60 -
a 50 ~-
1o 40 r
O
30
20 r
10 -.
0
0.0 1.0 2.0 3.0 4.0 5.0
Mercury Concentration in Fish (ppm)
6.0
7.0
3-141
-------
Tennessee
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
100
1 80
a
•5 60
HI
u>
TO
§ 40
20
0 "—
Location Variables in Database
Number of records:
0 296 298 298
298
X 71 Z.
Water body Location
Latitude
Longitude
Agency
3-142
-------
Tennessee
Data Source: STORE!
Top Ten Fish Species3
Common Name
Channel catfish
Largemouth bass
Common carp
Drum family
Spotted bass
Percent
54
25
6
2
2
Common Name
Bullhead catfish
Bluegill sunfish
Golden redhorse
Rock bass
Freshwater drum
Percent
2
1
1
1
1
Species identified as "Unknown" were excluded from this analysis.
Fish Variables in Database
Number of records:
298 298 0 0 00000 297 0
?<*'
3-143
-------
Tennessee
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
*
A
*
/v
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
80
a
•5 60
HI
Q.
20
X X
/:
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-144
-------
Tennessee
Data Source: STORET
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Channel
catfish
Largemouth
bass
Common
carp
No. of
Samples
137
64
16
No. of
Fish
137
64
16
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.100
0.100
0.100
Max
(ppm)
0.650
0.830
0.340
Wt.
Mean
(ppm)b
0.173
0.255
0.208
Wt.
Median
(ppm)
0.120
0.190
0.200
Wt.
SDW<
0.111
0.153
0.076
cv
(%)"
64.32
59.97
36.72
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
Weighted Mean xw = S, wpc/1 Z),-w,-, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = */E.W.(x.-Xw)2 / (E.W.-l)
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Tennessee
100 -
90 ~.
. 80 -.
\ 7°-
! 60 -.
50 -.
40 -.
30 ~.
20 T
10 T
o-
>
JS
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
Mercury Concentration in Fish (ppm)
0.9
1.0
3-145
-------
Texas
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
80
a
s
•5 60
HI
Q.
20
Number of records:
248
248
248
248
248
Water body Location Latitude Longitude Agency
3-146
-------
Texas
Data Source: STORE!
Top Ten Fish Species"
Common Name
Sea catfish
Largemouth bass
Channel catfish
Blue catfish
Croaker
Percent
16
13
10
7
6
Common Name
Common carp
Bluegill sunfish
Long ear sunfish
Gafftopsail catfish
Southern flounder
Percent
6
5
4
3
3
Species identified as "Unknown" were excluded from this analysis.
Fish Variables in Database
Number of records:
248 248 102 89 191 11 81 7
71 54 129 66
3-147
-------
Texas
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
.E 80
o
Q.
•5 60
8 40
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-148
-------
Texas
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Sea catfish
Largemouth
bass
Channel
catfish
No. of
Samples
16
23
28
No. of
Fish
71
58
44
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.029
0.043
0.043
Max
(ppm)
0.543
0.657
1.186
Wt.
Mean
(ppm)b
0.152
0.237
0.193
Wt.
Median
(ppm)
0.129
0.243
0.171
Wt.
SDW<
0.104
0.145
0.180
cv
(%)"
68.75
61.28
93.20
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w^r, / X),. w,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = t/E.W (x -X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Texas
100-
90^
80^
:
70 -
40
30
20
10
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9
Mercury Concentration in Fish (ppm)
1.0 1.1
1.2
3-149
-------
Vermont
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
80
a
s
•5 60
HI
Q.
20
Number of records:
205
205
205
205
Water body Location
Latitude Longitude
Agency
3-150
-------
Vermont
Data Source: State
Top Ten Fish Species"
Common Name
Yellow perch
Largemouth bass
Brown bullhead
Smallmouth bass
Chain pickerel
Percent
27
20
10
8
7
Common Name
Lake trout
Northern pike
Brook trout
Rainbow trout
Pumpkinseed sunfish
Percent
7
6
5
3
2
Species identified as "Unknown" were excluded from analysis.
Fish Variables in Database
Number of records:
205 205 86 119 199 83 115 62 70 205 0 0
3-151
-------
Vermont
Data Source: State
' r-. *
irv
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
A •
; J
Mercury (ppm):
" 0.5 to 1
A < = 0.5
* <.
Mercury Variables in Database
Number of records:
100
80
a
s
•5 60
HI
Q.
20
X X
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-152
-------
Vermont
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Yellow
perch
Largemouth
bass
Brown
bullhead
No. of
Samples
46
11
11
No. of
Fish
127
93
47
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.090
0.150
0.050
Max
(ppm)
0.890
1.200
0.200
Wt.
Mean
(ppm)b
0.333
0.802
0.120
Wt.
Median
(ppm)
0.300
1.200
0.100
Wt.
SDW<
0.193
0.473
0.053
cv
(%)"
58.03
58.90
43.86
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = £,. wpc, I E,.vf,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = yEw/X.-Jt J2 / (E^.-
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Vermont
100^
90
_ 80
1 60^
Q_ :
> 5°^
1 40^
O 307
207
o-
0.0 0.2 0.4 0.6 0.8 1.0 1.2
Mercury Concentration in Fish (ppm)
1.4
1.6
3-153
-------
Virginia
Data Source: STORE!
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
Number of records:
0 135 135 135
135
100
to
= 80
&
TO
1
•s 60
HI
u>
| 40
20
n
-
-
X
1
X
Water body Location
Latitude
Longitude
Agency
3-154
-------
Virginia
Data Source: STORE!
Top Ten Fish Species"
Common Name
Redfm darter
Papio
Ocean pout
Coho salmon
Jack
Percent
18
18
12
11
8
Common Name
Logfm smelt
American dab
Calico surfperch
Atlantic sturgeon
Yellowfin goby
Percent
8
7
3
2
2
Species identified as "Unknown" were excluded from this analysis.
100
Fish Variables in Database
Number of records:
135 135 120
125 82
82
73 40 22
3-155
-------
Virginia
Data Source: STORE!
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
100
80
a
s
•5 60
HI
Q.
20
Mercury Variables in Database
Number of records:
X
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-156
-------
Virginia
Data Source: STORE!
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Redfin
darter
Papio
Ocean pout
No. of
Samples
18
15
12
No. of
Fish
89
87
60
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.010
0.010
0.006
Max
(ppm)
8.000
5.000
0.100
wt.
Mean
(ppm)b
0.677
0.336
0.035
Wt.
Median
(ppm)
0.050
0.040
0.030
Wt.
SDW<
2.152
1.160
0.033
cv
(%)"
317.76
344.92
93.03
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
Weighted Mean xw = S, wpCj I X),-vf,-, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = »/E.W.(x.-Xw)2 / (E.W.-
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Virginia
100:
90:
80
°l 70
| 60:
| 50 ^
42 40 :
1
O 30"
20:
10
0
0.0 1.0 2.0 3.0 4.0 5.0 6.0
Mercury Concentration in Fish (ppm)
7.0
8.0
9.0
3-157
-------
Washington
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
100
I 80
BO
HI
Q.
20
Location Variables in Database
Number of records:
57
57
57
Water body Location
Latitude Longitude
Agency
3-158
-------
Washington
Data Source: State
Top Ten Fish Species
Common Name
Largescale sucker
Largemouth bass
Rainbow trout
Brown bullhead
Channel catfish
Percent
48
12
10
9
3
Common Name
Common carp
Lake sturgeon
Mountain whitefish
Northern squawfish
Yellow perch
Percent
3
3
3
3
3
Fish Variables in Database
Number of records:
57 57 27 30 57 27 30
16 41
3-159
-------
Washington
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
Number of records:
100
80
a
s
•5 60
HI
Q.
20
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone. Qualifier
3-160
-------
Washington
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Largescale
sucker
Largemouth
bass
Rainbow
trout
No. of
Samples
40
4
3
No. of
Fish
79
20
16
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.036
0.024
0.020
Max
(ppm)
0.496
0.350
0.053
Wt.
Mean
(ppm)b
0.166
0.137
0.032
Wt.
Median
(ppm)
0.157
0.087
0.026
Wt.
SDW<
0.087
0.129
0.015
cv
(%)"
52.72
94.13
45.72
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = E, wpCj I E,w,, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = ,/E.W (x ~X )2 / (E.W -1)
w y z A i w' ^ i i '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Washington
100:
90:
80:
I 70
60
50:
o
Q_
jo 40 :
1
O
30
20:
10:
0:
0.0 0.1 0.1 0.2 0.2 0.3 0.3 0.4
Mercury Concentration in Fish (ppm)
0.4 0.5
0.5
3-161
-------
West Virginia
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Latitude and Longitude Data Not Available
Location Variables in Database
100
.E 80
TO
2 60
HI
O)
I
§ 40
20
Number of records:
127
127
X XI
72
Water body Location
Latitude
Longitude
Agency
3-162
-------
West Virginia
Data Source: State
Top Ten Fish Species
Common Name
Channel catfish
Common carp
Flathead sunfish
Smallmouth bass
Hybrid bass
Percent
43
12
9
8
5
Common Name
Bass
Greater redhorse
White bass
White crappie
Sauger
Percent
3
3
3
3
3
Number of records:
127 127 83
Fish Variables in Database
86 66
49
127
3-163
-------
West Virginia
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Latitude and Longitude Data Not Available
Mercury Variables in Database
Number of records:
100
E 80
TO
2 60
HI
O)
I
§ 40
20
x:
Detect, limit Hg basis -Wet Hg basis - Dry Hg cone. Qualifier
3-164
-------
West Virginia
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Channel
catfish
Common
carp
Flathead
catfish
No. of
Samples
57
14
10
No. of
Fish
184
52
38
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.030
0.056
0.100
Max
(ppm)
1.583
0.287
0.340
Wt.
Mean
(ppm)b
0.130
0.179
0.223
Wt.
Median
(ppm)
0.100
0.155
0.225
Wt.
SDW<
0.132
0.073
0.042
cv
(%)"
101.92
40.88
18.88
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, w/Xj I X),-vf,-, where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
c Weighted Standard Deviation: SDw = Ew/X.-Jt J2 / (E^.-
d CV = (SDW / xw) * 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in West Virginia
100:
90:
g 80:
| 70^
-------
Wisconsin
Data Source: State
Records Analyzed by Year
Sampling Locations
Total Samples
Location Variables in Database
100
.E 80
TO
•5 60
HI
6)
I
§ 40
20
Number of records:
3365
3365
3004
3004
3365
Water body Location
Latitude Longitude Agency
3-166
-------
Wisconsin
Data Source: State
Top Ten Fish Species
Common Name
Walleye
Northern pike
Rainbow smelt
Largemouth bass
Yellow perch
Percent
26
11
10
7
6
Common Name
Black crappie
Bluegill sunfish
Smallmouth bass
Slimy sculpin
Cyprinidae minnow
Percent
6
5
4
3
3
Fish Variables in Database
Number of records:
3365 3362 173 3192 3365 173 3190 154 3133 3198 156 11
3-167
-------
Wisconsin
Data Source: State
Geographic Distribution of Mercury Concentrations in Fish
Tissue on a Wet Weight and Fillet Basis
Mercury (ppm):
" 0.5 to 1
A < = 0.5
Mercury Variables in Database
100
.E 80
o
Q.
•5 60
8 40
Q.
20
Number of records:
3365 0
Detect, limit Hg basis - Wet Hg basis - Dry Hg cone.
Qualifier
3-168
-------
Wisconsin
Data Source: State
Mercury Concentration for the Three Most Abundant Species: Summary Statistics
Species
Walleye
Northern
pike
Rainbow
smelt
No. of
Samples
1183
478
6
No. of
Fish
1218
491
467
Mercury Statistics Weighted by No. of Fish in Sample3
Min
(ppm)
0.022
0.030
0.026
Max
(ppm)
1.800
1.600
0.071
Wt.
Mean
(ppm)b
0.440
0.317
0.034
Wt.
Median
(ppm)
0.380
0.280
0.029
Wt.
SDW<
0.286
0.192
0.013
cv
(%)"
64.95
60.54
38.35
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed.
b Weighted Mean xw = S, -wxt / X),. w,., where w is the weight (# of fish in composite sample) and x is the average mercury
concentration (ppm) in the composite sample.
Weighted Standard Deviation: SD = t/E.W (x ~X )2 / (E.W -1)
w v z ' z w ' '
d CV=(SDw/xJ* 100
Cumulative Distribution of Mercury Concentrations
for All Fish Species in Wisconsin
100
90
80
60
°- 50-
0)
w 40^
I 30
O
207
0-
0.0
1.0 2.0
Mercury Concentration in Fish (ppm)
3.0
3-169
-------
SECTION 4
ANALYSIS AND ANALYSIS ISSUES
4.1 VARIABILITY IN THE DATA BASE
Although the data from each state are standardized and were subjected to a thorough quality
assurance process before being included in the data base, variability among the state data sets must
be accounted for when performing interpretive analyses. Several factors contribute to variability in
the data base, including those presented below:
States collect data for purposes other than mercury analyses, and not all sampling strategies
are based on a random sample. For example, data collected for the purpose of annual water
quality monitoring may not produce the same results as a site-specific study offish tissue
mercury concentrations.
• States use different techniques, including electrofishing, trap nets and gill nets, angling, and
trawling, to sample fish. The sampling techniques used by each state influence sample size,
fish size, and fish type.
• States do not adhere to the same standards for assimilating a composite sample. Although
grouping fish of the same species, size, and age is preferable, not all states have done so.
The absence of a standardized method for grouping fish may result in grouping different
species offish into composites, which can affect both the representativeness of the sample
and the results of analyses. For example, different results may be obtained from a composite
with two species (i.e., brown and rainbow trout) than from a composite of known genus (i.e.,
trout), but unknown species.
• States use various analytical procedures to measure the concentration of total mercury in
fish. Variation among analytical equipment, use of various protocols and procedures, and
different levels of laboratory staff experience can all bias the assessment of mercury
concentrations in fish. Mercury analyses reported on a wet weight basis cannot be directly
compared to concentrations reported on a dry weight basis.
To assist States and Tribes in conducting consistent fish tissue sampling and analysis, EPA has
published a guidance document covering topics such as target species selection, field procedures,
lab procedures, and data analysis and reporting (EPA 1995b).
4.2 TREATMENT OF NON DETECTS
Several states reported mercury concentrations as "non-detected," that is, the concentration of
mercury was not detectable given the limitations of the analytical equipment or measurement
method. For example, if the detection limit is 0.2 ppm, the sensitivity of the equipment and
analytical procedures is insufficient to measure mercury concentrations less than 0.2 ppm.
When performing data analysis on mercury concentrations, non-detected concentrations, or
"nondetects," can be treated in several ways. For example, nondetects can be excluded from the
analysis, decreasing the number of available records. If non-detected records are excluded from the
4-1
-------
National Mercury Survey
analysis for the state of Alabama, for example, the number offish analyzed decreases from 2,236 to
916. Alternatively, the detection limit for the particular mercury method can be used to provide an
estimate of the mercury concentration. This approach does not decrease the number of records in
the data base, but it does provide a conservative estimate of the mercury concentration. Less
conservative treatment of nondetects assigns the mercury concentration equal to half the detection
limit. The most non-conservative treatment is to assign a value of zero to all nondetects. This
approach, however, may impact the analyses when a significant number of nondetects are present
in the data base.
A sensitivity analysis was performed using two extreme treatments of nondetects to determine (1)
the impact of removing all non-detected values from the data base, (2) the influence of setting
nondetects equal to the detection limit, and (3) the effect of setting nondetects equal to zero. Table
4-1 presents the results analyzing the changes in the weighted mean and median mercury
concentrations in fish for each state. The percent differences of mean mercury concentrations with
varying treatment of non detects presented in Table 4-1 indicate that non detects may cause mean
mercury concentration to vary by as much as 50 percent. For most states, however, the difference
is within 10 percent. The percent difference is greater than 20 percent for Alabama, Delaware,
Kentucky, and Oklahoma. A closer examination of the numbers reveals that most of the mean
mercury concentrations are relatively low (below 0.5 ppm), even with the most conservative
approach (i.e., setting non detects equal to the detection limit.) Therefore, the difference is not
significant in practice, and the most conservative approach for all data analyses (i.e., set all non
detects to the detection limit) was used.
The number of records analyzed for each treatment of the nondetects is also presented in Table 4-1.
In the sensitivity analyses, the differences in the mean and median mercury concentrations among
each of the three possible treatments of the nondetects may be influenced by the number of non-
detect records in the data base. The magnitude of the detection limit also impacts the mean and
median concentrations that result from incorporation of non detects into analyses. Although the
detection limit generally is a fixed number for most states, the magnitude of the detection limit must
be considered for those states that report multiple detection limits.
4-2
-------
National Mercury Survey
Table 4-1. Effects of Non-detected Observations on Mercury Concentrations in Fish3
St.
AL
AZ
AR
CA
CT
DE
DC
FL
GA
IL
IN
IA
KS
KY
LA
ME
MD
MA
MI
MN
MS
MO
NE
NH
NJ
NM
NY
NC
OH
OK
OR
PA
SC
TN
TX
VT
VA
WA
wv
WI
Total Observations Including
Detected Records Only
No. of
Records
208
51
809
386
618
48
75
2819
667
99
502
130
193
200
1021
352
317
550
4199
5361
378
390
271
169
373
350
968
2808
1457
342
554
276
498
230
199
201
58
56
104
3364
No. of
Fish
916
51
2307
4289
618
129
75
2819
3068
428
1978
545
755
828
1021
1547
799
550
5063
21145
1127
2061
1022
185
373
350
968
4640
4547
1644
887
1102
592
230
410
498
268
159
345
4659
Mean
(ppm)
0.364
1.147
0.673
0.151
0.464
0.078
0.090
0.604
0.172
0.159
0.172
0.146
0.164
0.276
0.318
0.499
0.041
0.285
0.233
0.225
0.575
0.126
0.184
0.359
0.530
0.454
0.394
0.383
0.133
0.289
0.304
0.232
1.085
0.253
0.210
0.464
0.534
0.133
0.173
0.264
Med.
(ppm)
0.240
1.060
0.590
0.086
0.391
0.062
0.076
0.510
0.100
0.120
0.143
0.110
0.150
0.156
0.236
0.410
0.026
0.233
0.170
0.160
0.510
0.119
0.141
0.250
0.280
0.290
0.310
0.230
0.109
0.190
0.186
0.178
0.985
0.195
0.150
0.340
0.057
0.114
0.143
0.190
Total Observations Including Both
Detected and Nondetected (ND) Records
ND=0
No. of
Records
472
51
829
409
618
69
75
2819
745
105
505
132
193
248
1093
354
317
550
4199
5450
378
402
271
177
373
467
993
2808
1531
550
585
301
675
297
248
205
133
57
127
3364
No. of
Fish
2236
51
2389
4914
618
190
75
2819
3412
458
1987
549
755
1323
1093
1557
799
550
5063
21537
1127
2077
1022
199
373
467
993
4640
4739
2916
935
1127
826
297
673
514
676
164
428
4659
Mean
(ppm)
0.149
1.147
0.650
0.132
0.464
0.053
0.090
0.604
0.155
0.149
0.171
0.145
0.164
0.173
0.297
0.496
0.041
0.285
0.233
0.221
0.575
0.125
0.184
0.334
0.530
0.340
0.384
0.383
0.127
0.163
0.289
0.227
0.777
0.196
0.128
0.449
0.212
0.129
0.139
0.264
Med.
(ppm)
0.000
1.060
0.560
0.071
0.391
0.042
0.076
0.510
0.100
0.100
0.143
0.110
0.150
0.020
0.212
0.400
0.026
0.233
0.170
0.160
0.510
0.119
0.141
0.230
0.280
0.210
0.310
0.230
0.106
0.100
0.180
0.170
0.530
0.170
0.060
0.330
0.000
0.111
0.108
0.190
ND=Detection Limit
No. of
Records
472
51
829
409
618
69
75
2819
745
105
505
132
193
248
1093
354
317
550
4199
5450
378
402
271
177
373
467
993
2808
1531
550
585
301
675
297
248
205
133
57
127
3364
No. of
Fish
2236
51
2389
4914
618
190
75
2819
3412
458
1987
549
755
1323
1093
1557
799
550
5063
21537
1127
2077
1022
199
373
467
993
4640
4739
2916
935
1127
826
297
673
514
676
164
428
4659
Mean
(ppm)
0.296
1.147
0.654
0.135
0.464
0.070
0.090
0.604
0.162
0.154
0.171
0.145
0.164
0.249
0.298
0.496
0.041
0.285
0.233
0.221
0.575
0.125
0.184
0.341
0.530
0.365
0.385
0.383
0.130
0.211
0.292
0.228
0.850
0.219
0.154
0.451
0.237
0.129
0.172
0.264
Med.
(ppm)
0.170
1.060
0.560
0.071
0.391
0.050
0.076
0.510
0.100
0.100
0.143
0.110
0.150
0.167
0.212
0.400
0.026
0.233
0.170
0.160
0.510
0.119
0.141
0.230
0.280
0.210
0.310
0.230
0.108
0.140
0.180
0.170
0.530
0.170
0.086
0.330
0.050
0.111
0.143
0.190
%
Diff."
49.63
0.00
0.56
2.35
0.00
24.54
0.00
0.00
4.25
3.61
0.05
0.00
0.00
30.70
0.10
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
2.06
0.00
6.86
0.31
0.00
1.91
22.75
1.15
0.42
8.53
10.32
16.86
0.34
10.60
0.00
18.92
0.00
a Note: If the number of fish in the composite sample is missing, a value of 1 was assumed. Weighted Mean xw = E, wIxl I E, wl, where
w is the weight (# offish in composite sample) and x is the average mercury concentration (ppm) in the composite sample.
b Percent Difference = (| x - y / x) * 100, where x = mean concentration when ND=Detection Limit, and y = mean concentration when
ND=0.
-------
National Mercury Survey
4.3 MERCURY CONTENT FOR DIFFERENT CATEGORIES OF FISH
Recognizing the limitations in the quantitative aspects of the data (see Section 4.1), this data base
can be used to explore potential nationwide differences in mercury concentrations of various
categories offish. While such an analysis may be possible to conduct on a state-by-state basis, we
examined the data on a national basis only, due to limitations in sample sizes within some states.
For this examination, an EPA data base (EPA 1997) that sorts fish species into categories on the
basis of scientific name is used. Each species name in the program is coded according to whether
it is resident (remaining for most of its life cycle within a given body of water) or migratory
(periodically moving from one body of water to another during its life cycle, such as migrating to
the ocean from a high-mountain river); demersal (bottom-water habitat) or pelagic (open-water
habitat); and edible (typically consumed by humans) or inedible (typically not eaten by humans).
The data base contains common and scientific names that are coded according to these categories:
1. Resident (r) versus migratory (m);
2. Edible (e) versus inedible (i); and
3. Demersal (d) versus pelagic (p).
The fish information was sorted into two classes in each of the three categories by fish name. This
analysis is incomplete, because matches could not be made for all fish species in the data base, and
not all data currently included in the data base were used (additional data from CT, MA, MI, MN,
NJ, and WV were added subsequent to this analysis). Distribution functions of the cumulative
percent offish species versus mercury concentration in tissues (in ppm) were generated with the
results for resident versus migratory in Figure 4-1; for edible versus inedible in Figure 4-2; and for
demersal versus pelagic in Figure 4-3. Summary statistics including the minimum, maximum,
weighted mean, and the mercury concentration for the 50th, 75th, 80th, 90th, 95th, and 99th percentiles
for the distributions, are shown in Table 4-2. These figures and tables indicate that higher mercury
concentrations occurred in resident fish than in migratory fish. Higher mercury concentrations were
also observed in pelagic than in demersal fish species, and edible fish have higher mercury
concentrations than inedible ones.
4-4
-------
National Mercury Survey
[Figure 4-1. Cumulative Distribution of Mercury Concentrations in Resident & Migratory Fish |
100
BO
80
v«
b 70
8 eo
i*
°- 50
5"
I -10
1 30
O
~\
^^-^^^^ -
^ „-""
/ *•**"
/ f
j r
/ /
t
f
(
1 !
r
i 1
?o 1 /
10
0
i
t
! 1 f 1 ! ! i i 1 ] i
0.0 0.1 0.2 0.3 0.4 0.5 0.6 ft.? O.B 0.9 1,0 i
i
5
i
i
1.?. 1.3 M 1,5 1.6 1.7 1.8 t.e 2.0
Mercury Concetilralton jppm)
Figure 4-2. Cumulative Distribution of Mercury Concentrations in Edible and Inedible Fish |
8.
c
S3
Q.:
0.
?
f
3
F
3
O
100
so
30
70
'60
SO
4C
30
20
10
0
_^_,_ ______ . ,_,____. ,_
/•- ^ „ ~~ — ~~ ~~ \
*f ** *"
X**'
s'
J f
1 J
I -*"
/ J
( 1
1 f
J r
J ''
/ t
I
} 1
j /
1 ' ! Inedlhto ~" ~ 1
I ' 1 • \
I'
Illflllfilll -ITIIITI
0.0 O.I 0.2 0,3 0,4 0,5 0.6 0.7 0.8 1.8 1.0 1.1 1.8 1-3 1.4 1,8 1,6 1.7 1.8 19 2.0
Concentration (ppm)
4-5
-------
National Mercury Survey
[Figure 4-3. Cumulative Distribution of Mercury Concentrations in Demersal and Pelagic Fish |
0>
I
0.0 O.f OS 0.3 0,4 OS OJ 0.7 0.8 O9 t.O 1,1 if 1.3 14 I,S IS 1.7 tJ it 2,0
Table 4-2. Weighted Mean and Mercury Concentration (ppm) by Percentile for
Different Categories of Fisha'b
Category
Resident
Migratory
Demersal
Pelagic
Edible
Inedible
No. of
Fish
54,800
6,129
14,797
46,781
61,509
2,738
Min. Hg
(all fish)
0.001
0.001
0.001
0.001
0.010
0.001
Mean Hg
(all fish)
0.30
0.19
0.16
0.31
0.29
0.09
Max. Hg
(all fish)
8.00
6.00
8.00
7.59
7.59
8.00
Mercury Concentrations
for the following Percentiles (all fish):
50thc
0.18
0.10
0.10
0.20
0.18
0.05
75th
0.37
0.23
0.20
0.40
0.36
0.10
80th
0.45
0.26
0.23
0.48
0.43
0.10
90th
0.68
0.40
0.30
0.71
0.66
0.10
95th
0.94
0.64
0.49
0.97
0.92
0.13
99th
1.66
1.20
0.80
1.63
1.61
0.37
Note: If the number offish in the composite sample is missing, a value of 1 was assumed. Weighted Mean xw = E, wye, / Ej w,, where w
is the weight (# offish in composite sample) and x is the average mercury concentration (ppm) in the composite sample.
Not all data currently in the data base were used in this analysis (additional data from CT, MA, MI, MN, NJ, and WV were added
subsequent to this analysis).
This column is to read as follows: Fifty percent of the fish species in this category have median concentrations less than or equal to 0.18
ppm. Other columns can be similarly interpreted.
4-6
-------
National Mercury Survey
4.4 ADDITIONAL DATA
The national mercury data base represents a first step in assembling a nationwide source of
information that can be used to form hypotheses regarding potential accumulation of mercury in
geographical "hot spots" or in particular species offish. The utility of the data base for quantifying
mercury contamination on a national basis or with regard to a particular type or species offish can
be improved by incorporating additional environmental and biotic variables, as discussed in the
following subsections.
4.4.1 Environmental Parameters
pH: Fish in poorly buffered waters may accumulate elevated levels of mercury, as the tendency
for mercury to bioaccumulate appears to be inversely correlated with pH and alkalinity (or acid-
neutralizing capacity) in many aquatic systems (Wren and MacCrimmon, 1983). Deposition of
air-borne pollutants from the Midwest and other places in combination with bedrock geology
and watershed characteristics have reduced the natural buffering capacity of many water bodies
in the United States. Acidification of water bodies via atmospheric deposition from
anthropogenic sources not only subjects the fish to stress from the acid, but may also increase
exposure to metals; acidification increases the mobilization of metals from soils and sediments
by altering the partitioning of methylmercury between the water and sediments. In addition to
increased availability, acidification of lakes impacts fish uptake of mercury by enhancing
optimum conditions for methylation by microbial populations. For example, the rate of
microbial production of methylmercury is reported to be highest in lakes with pH ranging from
6 to 6.5 (Fagerstrom and Jernelov, 1972). The relationship between pH in water bodies and the
mercury concentrations in fish from those water bodies has been characterized using correlation
and regression analyses (Hanten, et al., 1997; NJDEP, 1994; Rose, et al., 1999).
Calcium: In addition to low pH, the bioavailability of methylmercury is enhanced by decreased
levels of calcium in water bodies. Substantial literature detailing the interaction of calcium and
metal regulation by aquatic organisms suggests this cation plays an important role in determining
mercury levels in fish tissue (Wren and MacCrimmon, 1983). Increased gill permeability at low
calcium levels (Spry et al., 1981) or competition between metals and calcium for cellular binding
sites (Zitko and Carson, 1976) is thought to be the mechanism of this effect.
Regional or Climatic Trends: In temperate waters, the accumulation of mercury by fish is most
rapid in summer, when feeding and metabolic rates of fish and microbial production of
methylmercury are highest (Weiner and Spry, 1994). Analyzing the relationship between water
temperature and mercury concentrations in fish on a national basis may provide insight on which
regions of the nation may be more prone to higher mercury concentrations in fish due to
geographical location. Although water temperature is not a variable available in the data base,
analyzing the mercury concentrations in fish species by season, using collection date as a
surrogate for temperature, may be a promising preliminary step to examining regional trends.
4-7
-------
National Mercury Survey
Volume and Depth: Wren and MacCrimmon (1983) reported that environmental parameters
such as lake volume and depth are important variables in explaining mercury concentrations in
the fish species commonly known as pumpkin seeds. This study postulated that shallow-water
species are exposed to a larger proportion of sediments containing mercury in the epilimnion and
in the littoral zone. Whole-lake experiments suggest that mercury tends to enter food chains
more rapidly in small, shallow lakes with high littoral-to-pelagic area ratios than in large, deep
lakes. Organisms that live, reproduce, and feed in the surface of water bodies experience much
different exposures than those that live, reproduce, and feed on seston and detritus in the water
column. Exposure of species that inhabit the benthic zone will also differ. Thus, additional
information on volume and depth of the aquatic system (e.g., river, small stream, lake) from
which fish samples were taken, as well as information on the sampling depth or feeding habitats,
may be useful.
Lake Classification: Improved descriptions of whether a water body is a seepage lake or a
drainage lake may be useful in examining mercury concentrations in fish. Mercury
concentrations in seepage lakes, which lack surface inflows, are generally not as high as mercury
concentrations in drainage lakes. In addition to direct influxes of mercury through wet and dry
deposition, drainage lakes also receive indirect contributions of mercury from runoff in the
watershed. Runoff enhances the amount of mercury entering a lake either by directly supplying
mercury from watershed soils or by supplying organic material to which mercury is bound. The
transport of organically bound mercury from the watershed thus increases the supply of mercury
available to fish (Zillioux et al., 1993). More definitive lake classification may therefore
enhance the understanding of mercury concentrations in fish tissue.
Wetlands: Concentrations of methylmercury tend to be higher in surface waters that drain
wetlands than in other waters. Wetlands, which may direct and supply discharges of mercury
wastes or runoff from mercuriferous sources, can confound interpretations of atmospheric
mercury deposition. The Florida Everglades and Davis Creek Reservoir in California provide
examples of the importance of wetlands and watershed runoff as sources of mercury. Although
Lindqvist et al. (1991) state that mercury runoff from watersheds is reduced when wetlands are
present, wetland transport of mercury from watersheds can occur because of the strong
association of mercury species with organic matter. Wetland disturbance and the creation of
new reservoirs increase the mobility of organic matter, suggesting that mercury may be
mobilized and thus become available to fish from both natural and anthropogenic sources.
Nutrient Conditions: Incorporating nutrient conditions or trophic status of the aquatic system
into the data base would be informative. Akielaszek and Haines (1981) reported higher levels
of mercury in trout from oligiotrophic (nutrient-poor) waters than in trout from eutrophic
(nutrient-rich) waters in unpolluted areas in Maine. Position in the trophic food web and
difference in available foods are important factors influencing the degree of bioaccumulation of
mercury in fish, but complexation and precipitation reactions that normally decrease the
availability of trace elements can also be important determinants. Such reactions are less
predominant in oligotrophic waters. Therefore, the mercuric ion (Hg+2 ) and methylmercury,
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National Mercury Survey
which both have a strong affinity for organic substances, are methylated in sediments or in the
water column and subsequently are accumulated in fish in oligiotrophic lakes in greater
concentrations than in fish in eutrophic lakes.
4.4.2 Fish Parameters
Diet: The trophic structure of a water body influences mercury concentrations in fish,
particularly for piscivorous fish species. Thus, information in the data base regarding feeding
habits and food-chain structure would be useful for analyzing the dietary influence of
methylmercury uptake in fish. Studies show that lake trout, Salvelinus namaycush, have higher
mercury concentrations when forage fish, such as rainbow smelt, Osmorius mordax, are present
(Akileaszek and Haines, 1981). Similarly, mercury concentrations in northern pike in a Finnish
lake lacking forage fish are approximately one-fourth those in northern pike in a nearby, similar
lake with forage fish (Weiner and Spry, 1994).
Age: Field studies indicate that most fish accumulate mercury throughout their lives. Thus,
age—and consequently size—of the fish are variables that impact the bioaccumulation of
mercury. In addition to increasing with age, mercury concentrations in fish tissue changes as the
diet of the maturing fish changes. The rate of methylmercury accumulation in lake trout, for
example, increases when the trout becomes large enough to switch from a diet of invertebrates
to a diet of forage fish. Age would be an important variable to examine in fish that become
completely piscivorous as adults. While very few states collect age data, many states record
length and weight, which may be used as indicators offish age. With this information, future
analyses can more carefully examine the relationship between fish species, age, and mercury
concentration.
Mercury Intoxication: Recording symptoms of methylmercury intoxication in laboratory
toxicity can be useful. Symptoms of acute mercury poisoning offish include increased secretion
of mucous, flaring of gill covers, increased rate of respiration, loss of equilibrium, and
sluggishness. Signs of chronic poisoning include emaciation (due to reduced food intake), brain
lesions, cataracts, inability to capture food, abnormal motor coordination, and various erratic
behaviors. Although it may be difficult to discern in field settings, the presence of such
symptoms, coincident with high concentrations of mercury in fish tissue, would serve to
strengthen any diagnoses of methylmercury toxicity.
4.5 PREDICTIVE STATISTICAL ANALYSIS
Many researchers have examined fish parameters, source parameters, environmental parameters, and
location parameters and performed studies to relate these parameters to the associated mercury
concentration in fish. The goals of these studies are to understand the factors causing or contributing
to mercury accumulation and to gain the ability to predict mercury accumulation both in the present
and in the future. Two general types of approaches have been used in these studies. Mechanistic
approaches aim to express chemical, physical, and biological processes mathematically, whereas
empirical approaches aim to explain relationships quantitatively using statistics, regardless of the
specifics of the underlying natural processes. These approaches are complementary and, when both
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National Mercury Survey
approaches are fully developed and produce the same results, the greatest level of understanding and
verification is achieved. Empirical approaches are quite useful for addressing problems such as
mercury accumulation in fish where the underlying natural processes are highly complex, are poorly
understood or described, and require basic research to fully express in mathematical terms. Both
approaches require high-quality data, assembled and organized in an accurate and logical manner.
Making use of the data compiled, EPA has initiated an empirical study of the fish parameters and
location parameters contained in this data base with additional source parameters and environmental
parameters that have been linked to mercury accumulation in fish from past mechanistic and
empirical studies. EPA's initial efforts have focused on a region in the southeastern United States
(Alabama, Arkansas, Louisiana, and Mississippi), where sufficient data are available, to demonstrate
a statistical approach for building a predictive model. This exercise involves conducting a three-part
statistical analysis, performed sequentially in a hierarchical fashion. EPA anticipates that this
approach, once fully developed and reviewed, can produce reasonable predictions of mercury
concentrations in fish from a subset offish parameters, environmental parameters, and location
parameters.
The objective of this statistical analysis is to explain the variability of mercury concentrations
associated with various contributing factors (such as water body pH, proximity to sources of
mercury, fish species, and fish size), as well as the inherent spatial variability, using established
advanced statistical methods. The first step in this analysis is to apply classification and regression
tree (CART) modeling to identify important variables in explaining the variance of mercury
concentrations. CART is a particularly useful technique to apply to non-continuous category
variables. For example, CART modeling could reveal a split in the data based on State (presumably
reflecting the variability inherent in different state sampling and analysis methods, as well as
geographic variability) or a split by Genus of fish (presumably reflecting differences primarily in
feeding behavior). The remaining variance in the data is analyzed using generalized additive
modeling (GAM), a nonparametric regression technique for revealing nonlinear relationships. The
GAM analysis can help reveal statistically significant predictor variables such as pH of the water
body (higher mercury concentrations would be expected in waters with lower pH) or fish Weight
(higher mercury concentrations would be expected in heavier fish, reflecting greater exposure
duration). Once large-scale trends have been removed, the final step of the analysis is to apply
universal kriging (a second-order polynomial function of spatial Latitude andLongitude coordinates)
to account for spatial trends in the data.
The resulting predictive model has great promise for application to this and other data compilation
efforts. Predictive models using the same general approach of CART, GAM, and kriging could be
constructed for various regions of the country and could result in different sets of predictor variables.
The predictive model can also be refined to better account for important variables that can be added
to the analysis as they become available. The model approach may be useful for predicting mercury
concentrations in fish for waters within a particular study region that have not yet been sampled, and
thus has conceivable utility for a variety of potential management applications. EPA intends to
continue these efforts and anticipates posting additional information and a description of an example
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predictive model for the southeastern U.S. study area on the Agency web site at www.epa.gov/ost
in the future as it becomes available.
4.6 POTENTIAL FUTURE USES OF THE DATA BASE
The national mercury data base may be used in the future to examine trends in mercury
concentrations across ecoregions. Using the data base across a multi-state region, perhaps by
ecoregion or watersheds, would be informative for several reasons. Examining the data by
ecoregions would provide a more holistic picture of the issues relevant to different geographical
areas. Mercury concentrations tend to vary across states. For example, in the Southeast, mercury
concentrations in fish tissue from the coastal plain are generally higher than those found in the
Piedmont or the montane regions.
Future analysis by ecoregion may enhance the understanding of the relationships among mercury
concentration, geographic location, and environmental characteristics particular to a type of aquatic
system. For example, acidic, organic-rich black waters commonly found in the southeastern coastal
plain will methylate mercury, making toxic forms of mercury more available to fish. Analyzing the
data by ecoregions may provide additional insight on potential sources of mercury. For example,
mercury may originate from non-localized sources such as incinerators or from localized land-use
modifications, such as mining operations, that liberate mercury from the crust of the earth.
Addressing mercury concentrations by ecoregion would require state geologic survey groups to
assist with assigning appropriate mapping coordinates. Mapping mercury concentrations in fish
tissue by ecoregions, particularly showing the relationship between concentration and elevation,
provides a useful means of presenting the data. Geographic Information System (GIS) mapping
software packages, which allow the integration and layering of data, could be used to examine the
impacts that pH, alkalinity, hardness, dissolved organic carbon, and other water quality
characteristics have on mercury speciation, solubility, and complexation. Also, mapping that allows
data integration would be useful for identifying the contribution of mercury from localized and non-
localized sources.
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SECTION 5
REFERENCES
Akileaszek, J., and T. Haines. 1981. Mercury in the muscle tissue offish from three northern
Maine lakes. Bull. Environ. Contam. Toxicol. 27:201-208.
Andren, A. and J. Nriagu. 1979. The global cycle of mercury. In: The Biogeochemistry of Mercury
in the Environment. J.O. Nriagu, ed. Elsevier/North Holland. Biomedical Press, New York. pgs.
1-21.
B.C. Environment. 1998. Metal concentrations in fish tissue from uncontaminated B.C. Lakes.
B.C. Ministry of the Environment, Water Management Division. Appendix I.
Bevelheimer, M.S., J.J. Beauchamp, B.E. Sample and G.R. Southworth. 1997. Estimation of
Whole-Fish Contamination Concentrations from Fish Fillet Data. Prepared by the Risk Assessment
Program, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831. Prepared for the U.S.
Department of Energy, Office of Environmental Management.
Birge, W., J. Black, A. Westerman, P. Francis, and J. Hudson. 1977. Embryopathic effects of
waterborne and sediment-accumulated cadmium, mercury and zinc on reproduction and survival of
fish and amphibian populations in Kentucky. University of Kentucky Water Resources Research
Institute, Lexington, Kentucky. Research Report 100, Project Number: A-061-KY.
Clarkson, T.W. 1992. Mercury: major issues in environmental health. Environ. Health Perspect.
100:31-38.
Fagerstrom, T., and A. Jernelov. 1972. Some aspects of the quantitative ecology of mercury.
Water Research 6:1193.
Fitzgerald, W. 1989. Atmospheric and oceanic cycling of mercury. In: Chemical Oceanography.
R.A. Duce, guest ed., J.P. Riley and R. Chester, eds. Academic Press, New York, NY. V10:pgs.
152-185.
Fitzgerald, W., and T. Clarkson. 1991. Mercury and monomethylmercury: Present and future
concerns. Environ. Health Perspectives. 96:159-166.
Hanten, R.P., Jr., R.M. Neumann, S.M. Ward, R.J. Carley, C.R. Perkins, and R. Pirrie. 1997
Relationships Between Largemouth Bass, Mercury Levels, and Environmental Characteristics of
Connecticut Lakes. ERI/97-01.
Huckabee, J., J. Elwood, and S. Hildebrand. 1979. Accumulation of mercury in freshwater biota.
In: The biogeochemistry of mercury in the environment. J.O. Nriagu, ed. Elsevier/North-Holland
Biomedical Press, New York. pgs. 277-302.
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Lindqvist, O., K. Johansson, M. Asstrup, A. Anderson, L. Bringmark, G. Hovsenius, A.
Iverfeldt, M. Mieli and B. Timm. 1991. Mercury in the Swedish environment - recent research on
causes, consequences and corrective methods. Water Air SoilPollut. 55: i-261.
Matida, Y., H. Kumada, S. Kimura, Y. Saiga, T. Nose, M. Yokote, and H. Kawatsu. 1971
Toxicity of mercury compounds to aquatic organisms and accumulation of the compounds by the
organisms. Bull. Freshwater Fish. Res. Lab. (Tokyo) 21:197-227'.
McDonald, D.D., M.G. Ikonomou, A-L Rantalaine, LH. Rogers, D. Sutherland, and J. Van
Oostdam. 1997. Contaminants in white sturgeon (Acipenser transmontanus) from the Upper Fraser
River, B.C. Canada. ETC 16(3):479-490.
NESCAUM. 1998. Northeast States andEastern Canadian Provinces Mercury Study, AFramework
for Action. Northeast States for Coordinated Air Use Management.
NJDEP. 1994. Preliminary Assessment of Total Mercury Concentrations in Fishes from Rivers,
Lakes and Reservoirs of New Jersey. New Jersey Department of Environmental Protection. Report
No. 93-15F.
Rose, J., M.S. Hutcheson, C.R. West, O.Pancorbo, et al. 1999. Fish mercury distribution in
Massachusetts, USA lakes. Environ. Toxicol. Chem. 7:1370-1379.
Roseijadi, G. 1992. Metallothioneins in metal regulation and toxicity in aquatic animals. Aquat.
Toxicol 22:81-114.
Rudd, J., A. Furutani, and M. Turner. 1980. Mercury methylation by fish intestinal contents.
Appl. Environ. Microbiol. 40:777-782.
Ruohtula, M., and J. Miettinen. 1971. Retention and excretion of 203Hg labeled methyl mercury
in rainbow trout. Oikos 26:385-390.
Spry, D., C. Wood, and P. Hodson. 1981. The effect of environmental acid on freshwater fish with
particular reference to the softwater lakes in Ontario and the modifying effects of heavy metals. A
literature review. Can. Tech. Rep. Fish. Aquat. Sci. No. 999, 144 pgs.
Takeuchi, T. 1968. Pathology of Minamata disease. In: Minamata Disease. Kumamoto University,
Japan, pgs. 141-228.
U.S. Environmental Protection Agency (EPA). 1995. National Forum on Mercury in Fish
Proceedings. EPA 823-R-95-002.
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U.S. Environmental Protection Agency (EPA). 1995b. Guidance for Assessing Chemical
Contaminant Data for Use in Fish Advisories. Volume 1 Fish Sampling and Analysis. Second
Edition. EPA 823-R-95-007.
U.S. Environmental Protection Agency (EPA). 1997. The Incidence and Severity of Sediment
Contamination in Surface Waters of the United States, Volume 1: National Sediment Quality Survey.
EPA 823-R-97-006.
Wiener, J. 1987. Metal contamination of fish in low pH lakes and potential implication for
piscivorous wildlife. Trans. 5 2nd North American Wildlife & Natural Resources Conference, pgs.
645-657.
Wiener, J., and D. Spry. 1994. Toxicological significance of mercury in freshwater fish. In:
Interpreting Concentrations of Environmental Contaminants in Wildlife Tissues. G. Heinz and N.
Beyer, eds. Lewis Publishers, Chelsea, Michigan.
Winfrey, M., and J. Rudd. 1990. Review—environmental factors affecting the formation of
methylmercury in low pH lakes. Environ. Toxicol. Chem. 9:853-869.
Wren, C., and H. MacCrimmon. 1983. Mercury levels in the sunfish, Lepomis gibbosus, relative
to pH and other environmental variables of Precambrian Shield lakes. Can. J. Fish. Aquat. Sci.
40:1737-1744.
Zillioux, E., D. Porcella, and J. Benoit. 1993. Mercury cycling and effects in freshwater wetland
ecosystems. Environ. Toxicol. Chem. 12:2245-2264.
Zitko, V., and W. Carson. 1976. A mechanism of the effects of water hardness on the lethality of
heavy metals to fish. Chemospheres 5:299-303.
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THE NATIONAL SURVEY OF
MERCURY CONCENTRATIONS IN FISH
DATA BASE SUMMARY
1990 -1995
APPENDIX
REQUEST FOR MERCURY CONCENTRATIONS IN FISH TISSUE DATA
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PROTECTION AGENCY
WASHINGTON, D.C,
W' -----
OFFICE Of
WAT6R
Mr. Srtan Farkus
?ublic Information Officer
wV Division of Environmental Prc
10 Mc.Jur.kia Road
Nitre-, West Virginia 25143-2506
We 3re. Writing CO reC!U€:£-t VOUr 3SSlSt8nCe On 311 XSSU€i Ol"
continuing concern to many Stares and the U. S, Environmental
Fret-action Agency -!S?A) - - the widespread occurrence of mercury
in frsh tissues. Because of this concern, EPA has begun a
orejace tc orDcect human health by developing a more detailed
Section 3G5 !b* (1) cf Che Clean Water Act: requires each
State tc isrec33re and submit a wa~er qua 1 icy assessraenc co ;he
E?A Adsiinistracer. As vcu are aware,, the 205 (b) report ccucains
a detailed description cf a State's wacar quality including an
evaluation of each State's attainment of "fish-able and
swirnmabie" goals of the Act. The fishabla goal is evaluated in
that cartion cf ths reoort devocad to fish consumption,
shell fishing, and aquatic life support uses.
EPA uses the 305ib: reports, in part, to target persistent
and emerging wacer -quality problems. Our review of r.he 305 !b)
reports, HPA's database of Stats-issued fish consumption
advisories, and ether references confirms that human exposure to
mercur/ ccntactiination in fish is an important public :iea_t:i
concern. For example, cur updated fish advisory dar.aoci.se
reveals that many States have _ssuad new or revised mercury-
advisories during the past several years. Unfortunately, the
advisory information that States provide to SPA usually does net
include the detailed fish tissue monitoring daua.
We are, therefore, writing to the £ish consumption advisory
rcntact for ea~h State. We are requesting your help in gathering
copies of existing fish tissue monitoring data for mercury thac
Tiay have been collected during the la.s~ five /ears (7Y31-951 . We
v/C'U^cL aocrscrats an e^fectroiij^c cooy o£ VOUJT o^ate 3 cistci ~n
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National Mercury Survey
whatever format Is In, especially if it be
converted Imported into a DB-B.SE-compatible We are
not asking you to duplicate any information that in
national such as STOEET; If your State's is In a
simply Identify
we will it. We of
written reports on in fish tissue that your State may
completed within last to five years. Other
available, closely-related technical would be
helpful. We to offer technical assistance
to to this request.
This compiled Information will two primary uses. One
is to SPA technical to with fish
advisories. Many States together to
Regional "mercury forces" which to
information mercury-related fish consumption advisories.
of our objectives is to compile and fish tissue
In an interim database, If feasible. this electronic
"library" available, It be a valuable to
mercury forces it will help
their .
EPA will also develop a preliminary national
characterization of the mercury issue. We will develop a
qualitative overview at as: availability
of data ongoing efforts, fish concentrations,
factors that might influence tissue concentrations (sources,
with particular methylating environments or
ecoregxons, etc.). Since several States have intensive research
efforts underway, EPS. will consult wlch States individually as
with coalitions. We national review will
provide a valuable perspective to agencies. Eventually,
Office of Water will compiled Information to improve
its overall quality process, including a
detailed "snapshot" of the mercury In che 305(b)
.
above-requested Information to: Mr, Rick
(4305); 401 M St., S.W.; Washington, D.C, 20460.
We would receiving the Information no later
February 23, 1996, so we can begin compiling the Information as
as possible. If you questions this project
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National Mercury Survey
or you technical In responding to
Information, feel to call Mr. at
(202) 260-0642. you for your in
.
Elizabeth Southerland
Acting Director
Applied
Division
Office of Technology
State 305(b) Coordinators
305(b)
Fish Contracts
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National Mercury Survey
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