DWQ-2025-004873

Methylmercury Criterion for the Protection of
Human Health: Criterion Support Document

Matt Smiley set the catch and release record for lake trout in 2019. The fish was caught at Flaming
Gorge and was 48 inches long. Photo credit: Matt Smiley.

June 12, 2025

UTAH DIVISION OF WATER QUALITY

Executive Summary
In 2001, the U.S. Environmental Protection Agency (EPA) issued a new recommended water quality criterion for
methylmercury to protect human health. The recommended methylmercury criterion is based on fish and shellfish
tissue because over 99% of the mercury exposures to the U.S. population are from eating fish and shellfish. The
main form of mercury in fish and shellfish is methylmercury. Methylmercury is made when bacteria methylate
mercury in the aquatic environment. The recommended criterion is 0.3 mg/kg wet weight methylmercury in fish
and shellfish tissues. Utah currently monitors mercury concentrations in fish and issues waterbody consumption
advisories when concentrations exceed 0.3 mg/kg.
The Utah Division of Water Quality recommends adoption of the 0.3 mg/kg wet weight methylmercury criterion to
Utah’s list of water quality criteria for human health in R317-2 Table 2.14.6. Adoption of the methylmercury
criterion may result in new impairment determinations for waters with existing fish consumption advisories. The
adoption of the methylmercury criterion is not expected to substantially impact the UDPES permitting program
because most waters affected by a consumption advisory are not impacted by permitted discharges. In addition,
mercury discharges in UPDES permits are already required to comply with a stringent mercury water quality
criterion of 0.000012 mg/l.

UTAH DIVISION OF WATER QUALITY

Contents
1.0 Introduction 1
1.1 Scope 1
1.2 Mercury in Utah Fish 1
1.3 Sources of Mercury in Utah. 2
1.4 EPA (2001) Methylmercury Criterion 2
2.0 Recommendations for Utah 4
2.1 Methylmercury Criterion 4
2.2 Implementation for Assessments and TMDLs 5
2.3 Implementation for UPDES Permits 5
2.4 Translators 6
2.5 Consumption Advisories 7
2.6 Recommended Rule Changes 7
3.0 References 8

UTAH DIVISION OF WATER QUALITY

1.0 Introduction
1.1 Scope
This criterion support document reviews the EPA (2001) recommended methylmercury criterion
for protection of human health and includes recommendations for adding a new statewide
methylmercury criterion for Utah. This criterion, if adopted, may be further modified based on
site-specific conditions (R317-2-7.1.c). Only the Utah Water Quality Board has the authority to
change Utah’s water quality standards by following Utah’s administrative rulemaking process. The
rulemaking process includes publication in the Utah Bulletin and opportunities for public
participation.
Excess mercury exposures can lead to adverse health effects in humans. ATSDR (1999) provides
the following information regarding mercury:
Mercury is a naturally occurring metal which has several forms. The metallic mercury is a shiny,
silver-white, odorless liquid. If heated, it is a colorless, odorless gas. Mercury combines with other
elements, such as chlorine, sulfur, or oxygen, to form inorganic mercury compounds or “salts,”
which are usually white powders or crystals. Mercury also combines with carbon to make organic
mercury compounds. The most common one, methylmercury, is produced mainly by microscopic
organisms in the water and soil
The nervous system is very sensitive to all forms of mercury. Methylmercury and metallic mercury
vapors are more harmful than other forms, because more mercury in these forms reaches the
brain. Very young children are more sensitive to mercury than adults. Mercury in the mother’s
body passes to the fetus and may accumulate there, possibly causing damage to the developing
nervous system.
Nearly all methylmercury exposures in the United States occur through eating fish and shellfish
(EPA, 2010; 2021). To protect human health, EPA (2001) recommends a criterion that is based on
methylmercury concentrations in fish tissue. This document discusses the EPA (2001)
methylmercury criterion, the available data on mercury in Utah fish, recommended criteria for
Utah, discussions of implementation of the proposed criterion, and proposed rule language.
1.2 Mercury in Utah Fish
For over 10 years, Utah has monitored the concentrations of mercury in thousands of game fish.
The concentrations of total mercury were measured and all of the mercury presumed to be
methylmercury. Most mercury in fish tissues (80-100%) is present as methylmercury (EPA, 2001).
When the average concentration of mercury in fish exceeds 0.3 mg/kg ww, the Utah Department
of Environmental Quality, Utah Department of Health, and Utah Division of Wildlife Resources
issue a joint consumption advisory. The public are notified of these advisories through press
releases, signs at the affected water bodies, and by publication on DWQ’s webpage. As of May
2024, Utah has issued fish consumption advisories due to mercury for 37 waterbodies in Utah.
1.3 Sources of Mercury in Utah.
In 2007, DEQ published the Mercury Strategic Plan that was prepared with the assistance of the
now inactive Mercury Workgroup. The Plan describes DEQs efforts to identify and address the
potential sources of mercury in air, water, and soil in Utah. A multi-media approach is necessary
because atmospheric deposition and multimedia cycling of mercury are significant in many
waterbodies (EPA, 2010).
Mercury emissions are global and disperse widely in the atmosphere. Therefore, even waterbodies
without obvious local mercury sources can have elevated mercury concentrations in water and
biota. There are both natural and anthropogenic sources of mercury. Natural sources of mercury

UTAH DIVISION OF WATER QUALITY 1

include geothermal emissions and geological sources. Anthropogenic sources can include
combustion, mining, and manufacturing. In particular, coal-fired power plants are the leading
source of atmospheric mercury emissions in the United States.
Mercury enters the aquatic food web when divalent mercury in water and sediments is converted
through microbial action to methylmercury. Methylmercury is retained in fish tissue and can
biomagnify up the food web. Methylation rates are generally higher under low oxygen conditions
and in the presence of organic matter.
Mercury detected in fish in U.S. surface waters is from both U.S. and international sources (EPA,
2005). EPA estimates that approximately 83 percent of the atmospheric mercury deposited on
land and water in the U.S. is from sources outside the United States and Canada, and from
natural and re-emitted sources. This mercury can be converted to methylmercury in aquatic
environments by microbial organisms.
EPA’s air quality modeling indicates that domestic sources influence mercury deposition much
more in the eastern United States, and international sources are a more significant contributor to
mercury deposition in the western United States, where relatively few domestic sources exist.
1.4 EPA (2001) Methylmercury Criterion
The EPA (2001) recommended methylmercury criterion is 0.3 mg/kg (wet weight) in edible fish
and shellfish tissue.
EPA (2010) determined that a fish tissue criterion was appropriate for methylmercury because:
● A criterion expressed as a fish tissue concentration is closely tied to the “fishable”
designated use goal for all waterbodies in the United States.
● A fish tissue concentration value is expressed in the same form (fish tissue) through
which humans are exposed to methylmercury.
● A fish tissue concentration value is more consistent with how fish advisories are issued.
● At environmentally relevant concentrations, methylmercury is currently easier to detect in
fish tissue than in water samples.
The recommended criterion considers methylmercury exposures to people from all sources
including air, drinking water, and food. Fish and shellfish consumption from recreational and
commercial sources account for over 99% of the general population’s exposure to methylmercury.
Of these exposures, the EPA (2001) estimated that 27% was from marine and estuarine species
obtained from commercial sources.The methylmercury from these other exposures are deducted
from the total allowable exposures from fish obtained recreationally and is called the relative
source contribution. Drinking water is not a significant source of exposure to methylmercury.
The methylmercury criterion is based on an assumed general population fish consumption intake
of 17.5 g/day for fish (about 14 lbs/year). This intake is based on national surveys for
recreationally-caught fish and reflects the 90th percentile of fish consumption rates from the
general public. This rate underestimates consumption rates for certain subpopulations, such as
subsistence fishers, who can consume significantly greater amounts of fish (EPA, 2016a). For the
sensitive subpopulations of “Women of Childbearing Age” and “Children”, EPA (2001) provides
higher consumption rates of 165 g/day and 156 g/day, respectively, that would result in a more
stringent criterion than 0.3 mg/kg.

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In the recommended criterion, methylmercury toxicity is estimated from the EPA Integrated Risk
Information System (IRIS) reference dose of 0.0001 mg/kg- day. The methylmercury reference
dose is based on the outcomes of epidemiological studies. The representativeness of the studied
populations for the overall U.S. population continues to be debated in scientific literature.
However, IRIS toxicity values are derived for use in all EPA programs and undergo rigorous
review. The Centers for Disease Control recommend a less stringent minimum risk level
(analogous to a reference dose) of 0.0003 mg/kg-day (ATSDR, 1999a) but do not recommend
this value for use in fish consumption advisories.
Consistent with other EPA human health criteria, the EPA methylmercury criterion does not
specify either an averaging time or exceedance frequency for the criterion. Although no exposure
duration is recommended, the human health criteria are intended to be protective for chronic
exposures (EPA 2000b). The EPA IRIS glossary defines chronic exposures as “Repeated
exposure by the oral, dermal, or inhalation route for more than approximately 10% of the life span
in humans.” The human lifespan recommended by the EPA (2014) Superfund program is 70
years and EPA (2011) recommends 78 years. Ten percent is 7 and 8 years, respectively. EPA
typically evaluates exposures over 7 years as chronic and less than 7 years as subchronic. This
information could support an averaging time of up to 7 years.
EPA (2001) does not explicitly recommend that the methylmercury criterion be expressed as an
average but averaging methods are described as possible implementation methods. For instance,
EPA (2010) discusses calculating average methylmercury concentrations for species and trophic
levels from individual fish samples within a waterbody and the use of composited fish samples.
Average concentrations and composite sampling are representative for chronic exposures.
Absent expressing the criterion as an average, the criterion would be interpreted as not-to-exceed
concentration in individual fish.

2.0 Recommendations for Utah
2.1 Methylmercury Criterion
DWQ recommends that Utah adopt the EPA (2001) water quality criterion of 0.3 mg/kg (ww) for
fish and shellfish tissue. The EPA IRIS reference dose 0.0001 mg/kg-bw/day is the best available
estimate of a “safe dose” for human consumption. No Utah-specific data are available for
consumption rates of recreationally-caught fish or shellfish and therefore, the EPA (2001) national
consumption rates are recommended. Likewise, no Utah-specific data are available for the
consumption rates or mercury concentrations for fish and shellfish from commercial sources. The
EPA (2001) relative source contribution is therefore presumed appropriate for Utah.
No specific averaging time or exceedance frequency are recommended consistent with EPA
(2001). In the absence of explicit designations, the averaging time will be instantaneous and the
exceedance frequency is never. Mercury concentrations in fish are less variable than water
concentrations (EPA, 2010). The fish tissue concentrations are a result of the fish exposures over
time and inherently integrate the variable water concentrations. When fish tissue can be assumed
to be in quasi-equilibrium with environmental concentrations, fish tissue concentrations are
representative of longer-term water concentrations which intrinsically is an averaging time for the
water. Similarly, no specific exceedance frequency is recommended because the fish tissue
concentrations already represent relatively long-term water concentrations and any adverse
human health effects are not acceptable.
2.2 Implementation for Advisories & Assessments
The implementation of methylmercury advisories and assessments in Utah is currently focused
on consumption of fish muscle tissue because that is presumed to be the primary route of
consumption and exposure for the general public. However, other routes of exposure are

UTAH DIVISION OF WATER QUALITY 3

possible. For example, some populations may also consume non-muscle fish tissue or catch and
consume crayfish. DWQ has not identified any quantitative data regarding specific populations or
waterbodies where this type of consumption may be more common or their consumption rates.
DWQ should continue to seek data and information regarding situations where the application of
methylmercury criteria to other types of tissue could be appropriate.
Adoption of a methylmercury criterion in Utah’s water quality standards is not expected to affect
the current process for issuing fish consumption advisories. Advisories are currently issued based
on the recommended 0.3 mg/kg criterion. Utah’s fish consumption advisories are issued jointly by
the Utah Department of Health, Utah Division of Wildlife Resources and the Utah Division of
Water Quality. The advisory process uses similar methods to those used by EPA to derive the
methylmercury criterion but the methods are not identical. Though advisories are based on the
same magnitude of mercury concentrations as the recommended criterion, the current advisories
were issued independent of a water quality criterion and the advisory process may deviate from
implementation of a methylmercury criterion for water quality assessments, TMDLs or permits.
Advisory methods and new consumption advisories are reviewed by the Utah Water Quality
Health Advisory Panel. Thirty seven waterbodies in Utah currently have fish consumption
advisories for mercury. Where adequate data are available, consumption advisories should
consider fish size, age, and trophic classes as well as any unique characteristics of the target
population of consumers for a waterbody such as rates of consumption, the types of tissue
consumed, and sensitivity to methylmercury.
Adoption of the new methylmercury criterion will require minor updates to assessment methods.
In particular, an updated criterion will result in lowering the threshold for impairment used in
assessments from 1 to 0.3 mg/kg. Current assessment methods rely on a t-test to determine if
species mean methylmercury concentrations exceed the assessment threshold. This approach is
consistent with recommendations in EPA (2010), and is appropriate to continue. Where analytical
resources are limited, the assessment may also choose to consider evaluating composite
samples (EPA 2010). EPA (2010) includes additional guidance regarding statistical methods,
sample sizes, and processes for evaluating methylmercury concentrations from composite fish
tissue samples.
Currently there are two waterbodies in Utah listed as impaired for mercury in fish tissue, Brough
Reservoir and Newcastle Reservoir. Lowering the threshold for impairment from 1 to 0.3 mg/kg is
expected to result in additional impairment listings for mercury in fish tissue, including potential
impairments for any of the waterbodies with current mercury fish tissue advisories. However,
some advisories are based on data that are over 10 years old and their representativeness of
current conditions should be evaluated when determining impairment status.
Assessment category decisions should also consider whether alternative assessment categories
may be appropriate depending on statistical uncertainty or where source investigations do not
identify water mercury sources. For example, the insufficient data category may be used when
there is uncertainty in comparing methylmercury concentrations to the water quality standard. The
‘impairment not caused by a pollutant’ (4C) category may also be appropriate where no water
sources of mercury are identified. For states that have a comprehensive mercury reduction
program, EPA has also recommended the use of a 5M category for waters impaired primarily by
atmospheric mercury sources (EPA 2007).
DWQ should continue to coordinate with and consult the Utah Department of Health and Human
Services, the Utah Division of Wildlife Resources, and the Water Quality Health Advisory Panel
when making decisions regarding the modification and application of methylmercury advisory and
assessment methods.
2.3 Implementation for TMDLS & UPDES Permits

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Implementation of a tissue-based criterion in total maximum daily load assessments (TMDLs) and
UPDES permits presents many challenges because TMDLs are typically based on water
concentrations (EPA, 2010). Whereas advisories and assessments are based on methylmercury
in tissues, reductions in mercury loads to waterbodies through TMDLS or permit limits would be
focused on total mercury concentrations. The determination of total mercury source reductions
necessary to meet methylmercury fish tissue criteria requires the development of site-specific
translators between water and tissue mercury concentrations (see Section 2.4). Where air
deposition is the primary source of mercury, variability in fish tissue concentrations within the
same airshed is likely attributable to site-specific factors affecting mercury methylation rates.
Where impairments are identified, preliminary investigations should focus on determining what
portion of the mercury is attributable to atmospheric sources versus water sources. Atmospheric
mercury is difficult to measure, so these investigations are anticipated to initially focus on
characterizing mercury concentrations in water. Where no apparent water sources of mercury
exist to an impaired waterbody, a low TMDL prioritization may be appropriate.
Permitted discharges are not expected to be the primary source of mercury for waters with
existing fish consumption advisories. Most of the Utah waters affected by fish consumption
advisories have no or very few permitted discharges upstream. Although some of these waters
may be impacted by historical mining activities, air deposition is expected to be a major
contributor of mercury to Utah waters.
The permitting impacts of adopting a methylmercury criterion are anticipated to be limited.
Currently, reasonable potential determinations for mercury are based on the existing 0.000012
mg/l mercury criterion, the likelihood of mercury being present in the effluent, and the
concentrations of mercury measured in the effluent. For publicly owned treatment works
(POTWs), mercury sources are also addressed by the pretreatment program. Reasonable
potential for mercury has only been identified in two Utah Pollution Elimination System (UPDES)
permits and these have been assigned a water quality-based effluent limit for mercury based on
the existing 0.000012 mg/l mercury criterion. More stringent mercury discharge limits are possible
in the future where methylmercury impairments downstream from point sources are identified, but
these would only occur after TMDL development which would include source determination and
translator development.
Utah’s current approach to regulating mercury discharges appears to be adequately protective for
methylmercury based on the lack of correlation between potential point sources of mercury and
fish observed consumption advisories. At locations where fish tissue concentrations indicate that
the Utah’s water-based criterion is not sufficiently protective, translators may need to be derived.
As discussed in Section 2.4, DWQ and EPA (2010) recommend that site-specific translators be
developed when translators are needed. EPA (2010) provides detailed recommendations for
evaluating and implementing reasonable potential analyses for methylmercury for discharge
permits.
2.4 Translators
Translators describe the relationship between methylmercury concentrations in fish tissues and
concentrations of mercury in water. This type of translator is also called a bioaccumulation factor
or biomagnification factor. With a translator, the concentration of mercury in water can be used to
predict the methylmercury concentration in fish tissue, or vice versa. When fish tissues exceed
the methylmercury criterion, a translator is used to determine how much the water concentrations
need to be reduced to achieve the fish tissue criterion. Once the water concentration is
established, a water quality-based effluent limit or TMDL can be derived. In these circumstances,
follow up monitoring to confirm the continued accuracy of site-specific translators is essential.
A translator is a simplified representation of complex and dynamic site-specific processes. As
presented in detail in EPA (2001, 2010), mercury is usually released to the environment in
inorganic forms. Once in the aquatic environment, mercury partitions between dissolved and

UTAH DIVISION OF WATER QUALITY 5

undissolved forms and between the water column and sediments. Methylmercury concentrations
are a result of methylation of mercury compounds by microbial organisms and demethylation by
microbial organisms and sunlight. Methylation rates are a function of organic carbon, sulfur, and
dissolved oxygen and anthropogenic perturbations of these constituents may also affect
methylmercury concentrations in fish. Methylmercury concentrations also tend to increase with
fish age and in higher trophic levels and therefore, species feeding characteristics and lifecycles
and the number of trophic levels at a site can influence the methylmercury concentrations
observed in fish.
Site-specific translators are developed by measuring mercury concentrations in both water and
fish tissue and calculating a relationship. For permitting applications, the total recoverable
mercury concentrations in water are compared to the edible fish tissue concentrations (EPA,
2010). A highly sensitive analytical method for the water is usually required along with special
sampling protocols to avoid sample contamination. However, even these methods may not be
sufficiently sensitive to quantify mercury concentrations in water.
For the translators to be valid, mercury concentrations in fish tissue should be at or near
equilibrium with the water. Fish tissues should be collected from fish most likely to be consumed
and to have the highest exposures (i.e., fish from upper trophic levels) and more than one
species may need to be sampled. EPA (2001, 2010, 2016) provides details on conducting
investigations to determine translators between water and tissue. If a permittee or other
interested parties intends to collect data to support a translator, DWQ pre-approval is strongly
recommended to ensure that the data will be appropriate to support the derivation. If site-specific
translators can’t be derived for e.g., a new discharge, EPA (2001) does provide draft national
translators (bioaccumulation factors). These translators are anticipated to be protective but may
be more stringent than necessary.
By default, all mercury detected in fish is assumed to be methylmercury (EPA, 2000a). In some
situations, verification of this assumption may be warranted. These situations include when a
small change to the assumption of 100 percent methylmercury would affect the regulatory
outcome (e.g., impairment determination or reasonable potential). Most mercury in fish tissues is
methylmercury but percentages as low as 80 percent have been observed (EPA, 2000a).
2.6 Recommended Rule Changes
A markup of the recommended changes to the standards in UAC R317-2-14 is shown below. The
proposed additions are underlined. The criterion is specified as a wet-weight concentration of
methylmercury in mg/kg in edible fish tissue.

TABLE 2.14.6
LIST OF HUMAN HEALTH CRITERIA (CONSUMPTION)

Chemical Parameter Water and Organism Organism Only
and CAS # (ug/L) (ug/L)

Class 1C Class
3A,3B,3C,3D

Antimony 7440-36-0 5.6 640
Arsenic 7440-38-2 A A
Beryllium 7440-41-7 C C
Chromium III 16065-83-1 C C
Chromium VI 18540-29-9 C C

UTAH DIVISION OF WATER QUALITY 6

Copper 7440-50-8 1,300
Mercury 7439-97-6 A A
Methylmercury 22967-92-6 0.3 E 0.3 E
Nickel 7440-02-0 610 4,600
Selenium 7782-49-2 170 4,200
Thallium 7440-28-0 0.24 0.47
Zinc 7440-66-6 7,400 26,000
Free Cyanide 57-12-5 4 400
Asbestos 1332-21-4 7 million
Fibers/L
2,3,7,8-TCDD Dioxin 1746-01-6 5.0 E -9 B 5.1 E-9
B
Acrolein 107-02-8 3 400
Acrylonitrile 107-13-1 0.061 7.0
Benzene 71-43-2 2.1 B 51 B
Bromoform 75-25-2 7.0 B 120 B
Carbon Tetrachloride 56-23-5 0.4 B 5 B
Chlorobenzene 108-90-7 100 MCL 800
Chlorodibromomethane 124-48-1 0.80 B 21 B
Chloroform 67-66-3 60 B 2,000 B
Dichlorobromomethane 75-27-4 0.95 B 27 B
1,2-Dichloroethane 107-06-2 9.9 B 2,000 B
1,1-Dichloroethylene 75-35-4 300 MCL 20,000
1,2-Dichloropropane 78-87-5 0.90 B 31 B
1,3-Dichloropropene 542-75-6 0.27 12
Ethylbenzene 100-41-4 68 130
Methyl Bromide 74-83-9 100 10,000
Methylene Chloride 75-09-2 20 B 1,000 B
1,1,2,2-Tetrachloroethane
79-34-5 0.2 B 3 B
Tetrachloroethylene 127-18-4 10 B 29 B
Toluene 108-88-3 57 520
1,2 -Trans-Dichloroethylene
156-60-5 100 MCL 4,000
1,1,1-Trichloroethane 71-55-6 10,000 MCL 200,000
1,1,2-Trichloroethane 79-00-5 0.55 B 8.9 B
Trichloroethylene 79-01-6 0.6 B 7 B
Vinyl Chloride 75-01-4 0.022 1.6
2-Chlorophenol 95-57-8 30 800
2,4-Dichlorophenol 120-83-2 10 60
2,4-Dimethylphenol 105-67-9 100 3,000
2-Methyl-4,6-Dinitrophenol
534-52-1 2 30
2,4-Dinitrophenol 51-28-5 10 300

UTAH DIVISION OF WATER QUALITY 7

3-Methyl-4-Chlorophenol
59-50-7 500 2,000
Pentachlorophenol 87-86-5 0.03 B 0.04 B
Phenol 108-95-2 4,000 300,000
2,4,5-Trichlorophenol 95-95-4 300 600
2,4,6-Trichlorophenol 88-06-2 1.5 B 2.8 B
Acenaphthene 83-32-9 70 90
Anthracene 120-12-7 300 400
Benzidine 92-87-5 0.00014 B 0.011 B
BenzoaAnthracene 56-55-3 0.0012 B 0.0013
B
BenzoaPyrene 50-32-8 0.00012 B 0.00013
B
BenzobFluoranthene 205-99-2 0.0012 B 0.0013
B
BenzokFluoranthene 207-08-9 0.012 B 0.013 B
Bis2-Chloro1methylether
542-88-1 0.00015 0.017
Bis2-Chloro1methylethylether
108-60-1 200 B 4000
Bis2-ChloroethylEther
111-44-4 0.030 B 2.2 B
Bis2-Chloroisopropy1Ether
39638-32-9 1,400 65,000
Bis2-EthylhexylPhthalate
117-81-7 0.32 B 0.37 B
Butylbenzyl Phthalate
85-68-7 0.10 0.10
2-Chloronaphthalene 91-58-7 800 1,000
Chrysene 218-01-9 0.12 B 0.13 B
Dibenzoa,hAnthracene 53-70-3 0.00012 B 0.00013
B
1,2-Dichlorobenzene 95-50-1 1,000 3,000
1,3-Dichlorobenzene 541-73-1 7 10
1,4-Dichlorobenzene 106-46-7 300 900
3,3-Dichlorobenzidine
91-94-1 0.049 B 0.15 B
Diethyl Phthalate 84-66-2 600 600
Dimethyl Phthalate 131-11-3 2,000 2,000
Di-n-Butyl Phthalate 84-74-2 20 30
2,4-Dinitrotoluene 121-14-2 0.049 B 1.7 B
Dinitrophenols 25550-58-7 10 1,000
1,2-Diphenylhydrazine
122-66-7 0.03 B 0.2 B

UTAH DIVISION OF WATER QUALITY 8

Fluoranthene 206-44-0 20 20
Fluorene 86-73-7 50 70
Hexachlorobenzene 118-74-1 0.000079 B
0.000079 B
Hexachlorobutadiene 87-68-3 0.01 B 0.01 B
Hexachloroethane 67-72-1 0.1 B 0.1 B
Hexachlorocyclopentadiene
77-47-4 4 4
Ideno 1,2,3-cdPyrene
193-39-5 0.0012 B 0.0013
B
Isophorone 78-59-1 34 B 1,800 B
Nitrobenzene 98-95-3 10 600
N-Nitrosodiethylamine 55-18-5 0.0008 B 1.24 B
N-Nitrosodimethylamine
62-75-9 0.00069 B 3.0 B
N-Nitrosodi-n-Propylamine
621-64-7 0.0050 B 0.51 B
N-Nitrosodiphenylamine
86-30-6 3.3 B 6.0 B
N-Nitrosopyrrolidine 930-55-2 0.016 B 34 B
Pentachlorobenzene 608-93-5 0.1 0.1
Pyrene 129-00-0 20 30
1,2,4-Trichlorobenzene
120-82-1 0.071 MCL 0.076
Aldrin 309-00-2 0.00000077 B
0.00000077 B
alpha-BHC 319-84-6 0.00036 B 0.00039
B
beta-BHC 319-85-7 0.0080 B 0.014 B
gamma-BHC (Lindane) 58-89-9 4.2 MCL 4.4
Hexachlorocyclohexane (HCH)
Technical 608-73-1 0.0066 0.010
Chlordane 57-74-9 0.00031 B 0.00032
B
4,4-DDT 50-29-3 0.000030 B
0.000030 B
4,4-DDE 72-55-9 0.000018 B
0.000018 B
4,4-DDD 72-54-8 0.00012 B 0.00012
B
Dieldrin 60-57-1 0.0000012 B
0.0000012 B
alpha-Endosulfan 959-98-8 20 30
beta-Endosulfan 33213-65-9 20 40

UTAH DIVISION OF WATER QUALITY 9

Endosulfan Sulfate 1031-07-8 20 40
Endrin 72-20-8 0.03 0.03
Endrin Aldehyde 7421-93-4 1 1
Heptachlor 76-44-8 0.0000059 B
0.0000059 B
Heptachlor Epoxide 1024-57-3 0.000032 B
0.000032 B
Methoxychlor 72-43-5 0.02 0.02
Polychlorinated Biphenyls
(PCBs) 1336-36-3 0.000064 B,D
0.000064 B,D
Toxaphene 8001-35-2 0.00070 B 0.00071
B
FOOTNOTES:
A. See Table 2.14.2
B. Based on carcinogenicity of 10-6 risk.
C. EPA has not calculated a human criterion for this
contaminant. However, permit authorities should address
this contaminant in NPDES permit actions using the State's
existing
narrative criteria for toxics
D. This standard applies to total PCBs.
E. mg/kg wet weight in edible fish and shellfish
tissue

3.0 References
Agency for Toxic Substances and Disease Registry (ATDSR), 1999. Mercury Tox FAQs.
https://www.atsdr.cdc.gov/toxfaqs/tfacts46.pdf
Agency for Toxic Substances and Disease Registry (ATDSR), 1999a. Toxicological Profile for
Mercury.
Environmental Protection Agency (EPA) 2021.
https://www.epa.gov/mercury/how-people-are-exposed-mercury. Accessed August, 2021
EPA (U.S. Environmental Protection Agency). 2000a. Guidance for Assessing Chemical
Contaminant Data for Use in Fish Advisories. Volume 1: Fish Sampling and Analysis, 3rd ed.
EPA/823/B-00/007. Washington, DC: U.S. Environmental Protection Agency, Office of Water.
http://www.epa.gov/ost/fishadvice/volume1/ index.html
EPA (U.S. Environmental Protection Agency). 2000b. Methodology for Deriving Ambient Water
Quality Criteria for the Protection of Human Health (2000). EPA-822-B-00-004
EPA (U.S. Environmental Protection Agency). 2001. Water Quality Criterion for the Protection of
Human Health: Methylmercury. Final. EPA-823-R-1-001

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EPA (U.S. Environmental Protection Agency). 2005. Technical Support Document, Revision of
December 2000 Regulatory Finding on the Emissions of Hazardous Air Pollutants From Electric
Utility Steam Generating Units and the Removal of Coal- and Oil-Fired Electric Utility Steam
EPA (U.S. Environmental Protection Agency). 2007. Memorandum: Listing Waters Impaired by
Atmospheric Mercury Under Clean Water Act Section 303(d): Voluntary Subcategory 5m for
States with Comprehensive Mercury Reduction Programs.
https://www.epa.gov/tmdl/listing-waters-impaired-atmospheric-mercury-voluntary-subcategory
-5m-states-comprehensive
EPA (U.S. Environmental Protection Agency). 2010. Guidance for Implementing the 2001
Methylmercury Criterion. EPA-823-10-001.
EPA (U.S. Environmental Protection Agency). 2011. Exposure Factors Handbook.
EPA (U.S. Environmental Protection Agency). 2014. Memorandum: Human Health Evaluation
Manual, Supplemental Guidance: Update of Standard Default Exposure Factors. OSWER
Directive 9200.1-120.
EPA (U.S. Environmental Protection Agency). 2016. Technical Support for Adopting and
Implementing EPA’s 2016 Selenium Criterion in Water Quality Standards. Draft. EPA-820-F-010
EPA (U.S. Environmental Protection Agency). 2016a. Guidance for Conducting Fish Consumption
Surveys. 823B16002
Utah Department of Health (UDOH). 2012. Utah Fish Advisories, Changes to Utah Fish
Consumption Values.

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