oEPA

EPA 823-F-24-011

FACT SHEET

Contaminants to Monitor in Fish and Shellfish Advisory Programs

July 2024

Summary

Fish and shellfish advisory programs in states, Tribes, and territories monitor and analyze contaminants in fish
and shellfish in waterbodies within their jurisdictions. When contaminants occur in high enough concentrations
to potentially affect the health of people eating fish and shellfish from those waters, those programs issue
consumption advisories. To help state. Tribal, and territorial programs that issue fish and shellfish advisories, the
EPA recommends contaminants to monitor. The EPA has updated those recommendations. EPA added, among
other contaminants, a list of PFAS, thereby fulfilling the agency's commitment in the PFAS Strategic Roadmap to
finalize a list of PFAS for use in fish advisory programs. By issuing this factsheet, the EPA encourages advisory
programs to update the contaminants for which they monitor to protect people from eating potentially harmful
concentrations of contaminants.

Two Recommended Lists of Contaminants to Monitor

The EPA has established two lists of contaminants that advisory programs should consider monitoring in fish and
shellfish. Both lists contain substances that have been found to occur in the edible tissue offish and shellfish at
concentrations that may be of concern for human health.

1.	The first list, "Contaminants to monitor for advisories" (shown in Table 1), contains contaminants for
which the EPA or other federal agencies have released measures of oral toxicity in humans (e.g.,
reference dose, cancer slope factor). The EPA recommends that advisory programs use this list for
monitoring and issuing advisories with consumption limits.

2.	The second list, "Contaminants to monitor to watch" (shown in Table 2), contains contaminants for
which the EPA or other federal agencies have not yet released assessments of the effects on human
health. The EPA recommends that advisory programs monitor for compounds on this list to determine if
they are accumulating in fish in local waters. The advisory programs could calculate their own or use
another agency's scientifically based measures of oral toxicity in humans to calculate consumption
limits, or wait for such values to be released from a federal agency.

These lists of contaminants are not intended to be all-encompassing. Any time a fish and shellfish advisory
program deems a contaminant is of public health concern within its jurisdiction (e.g., there is a spill or known
discharge source, or it is found in high enough concentrations to potentially affect the health of people eating
fish and shellfish), they should include it in their contaminant monitoring program. In addition, inclusion of a
contaminant on these lists is not meant to imply that it is present in all waters nationwide. Inclusion indicates
the contaminant has been found to accumulate in fish or shellfish in ambient waters to a level that could be
deleterious to human health and is therefore capable of being problematic if released into local waters.
Furthermore, as part of this update effort the EPA did not conduct an extensive review of contaminants that
were already on the monitoring list to determine if any should be removed.

Contaminants to Monitor for Advisories

The EPA has updated its list of contaminants that it recommends fish and shellfish advisory programs include in
their contaminant monitoring program and issue consumption advisories for when needed. Table 1 contains the
complete updated list; new contaminants are in bold.

Page 1 of 4


-------
Table 1. Contaminants to monitor for fish and shellfish advisories

Group

Analyte



PFAS

Perfluorodecanoic acid (PFDA)





Perfluorohexane sulfonic acid (PFHxS)



Perfluorononanoic acid (PFNA)





Perfluorooctanoic acid (PFOA)





Perfluorooctane sulfonic acid (PFOS)



Cyanotoxins

Microcystes

Flame retardants

BDE-47

Pharmaceuticals

Amphetamine

Metals

Arsenic (inorganic)

Mercury (methylmercury)



Cadmium

Selenium



Lead

Tributyltin

Organochlorine pesticides

Chlordane, total (cis- and trans-

Endrin



chlordane, cis- and trans-nonachlor,

Heptachlor epoxide



oxychlordane)

Hexachlorobenzene



DDT, total (2,4' DDD, 4,4'-DDD, 2,4'-

Lindane (y-hexachlorocyclohexane;



DDE, 4,4'-DDE, 2,4'-DDT, 4,4'-DDT)

y-HCH)



Dicofol

Mi rex



Dieldrin

Toxaphene



Endosulfan (i and II)



Organophosphate

Chlorpyrifos



pesticides

Diazinon





Disulfoton





Ethion





Terbufos



Chlorophenoxy herbicides

Oxyfluorfen

Polycyclic aromatic

Dibenz[o,h]anthracene

Chrysene

hydrocarbons (PAHs)

Benzo[o]pyrene

Acenaphthene



Benz[a]anthracene

Acenaphthylene



Benzo[6]fluoranthene

Fluoranthene



Benzo[fc]fluoranthene

Fluorene



lndeno[l,2,3-cd]pyrene

Phenanthrene



Anthracene

Pyrene



BenzotgA'lperylene



Polychlorinated biphenyls

2,4' diCB 2,2',4,5,5' pentaCB 2,3',4,4',5,5' hexaCB

(PCBs)

2,2',5 triCB 2,3,3',4,4' pentaCB 2,3',4,4',5',6 hexaCB



2,4,4' triCB 2,3,4,4',5 pentaCB 3,3',4,4',5,5' hexaCB



3,4,4' triCB 2,3',4,4',5 pentaCB 2,2',3,3',4,4',5 heptaCB



2,2'3,5' tetraCB 2,3',4,4',6 pentaCB 2,2',3,4,4',5,5' heptaCB



2,2'4,5' tetraCB 2',3,4,4',5 pentaCB 2,2',3,4,4',5',6 heptaCB



2,2',5,5' tetraCB 3,3',4,4',5 pentaCB 2,2',3,4,4',6,6' heptaCB

Page 2 of 4


-------
Group

Analyte







2,3',4,4' tetraCB

2,2',3,3',4,4' hexaCB

2,2',3,4',5,5',6 heptaCB



2,3',4',5 tetraCB

2,2',3,4,4',5' hexaCB

2,3,3',4,4',5,5' heptaCB



2,4,4',5 tetraCB

2,2',3,5,5',6 hexaCB

2,2',3,3',4,4',5,6 octaCB



3,3',4,4' tetraCB

2,2',4,4',5,5' hexaCB

2,2',3,3',4,5',6,6' octaCB



3,4,4',5 tetraCB

2,3,3',4,4',5 hexaCB

2,2',3,3',4,4',5,5',6 nonaCB



2,2',3,4,5' pentaCB

2,3,3',4,4',5 hexaCB

2,2',3,3',4,4',5,5',6,6' decaCB



2,2',3,4',5 pentaCB

2,3,3',4,4',6 hexaCB



Dioxins

2,3,7,8-TCDD

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

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



1,2,3,7,8-PeCDD

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

OCDD



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





Furans

2,3,7,8-TCDF

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

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



1,2,3,7,8-PeCDF

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

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



2,3,4,7,8-PeCDF

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

OCDF



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





Contaminants to Monitor to Watch

The EPA also has created a new Contaminants to Monitor to Watch list that contains nine contaminants (two
cyanotoxins and seven PFAS compounds); these are shown in Table 2. These compounds were documented in
studies as occurring in edible tissue of consumed fish or shellfish species at a concentration that could be of
concern for human health, based on the EPA's analyses (described in Process section). These compounds do not
currently have measures of oral toxicity in humans (e.g., reference doses or cancer slope factors) issued by a
federal agency. After relevant toxicity values are developed for any of these contaminants, advisory programs
should evaluate the concentrations they have found in local fish and shellfish to determine if they need to issue
consumption advisories.

Table 2. Contaminants to monitor to watch

Group

Analyte

Cyanotoxins

BMAA (3-methylamino-L-alanine)

DABA (2,4-diaminobutyric acid dihydrochloride)

PFAS

Perfluorodecanesulfonic acid (PFDS)
Perfluorododecanoic acid (PFDoA)
Perfluoroheptanesulfonic acid (PFHpS)
Perfluorooctanesulfonamide (PFOSA)
Perfluorotetradecanoic acid (PFTeDA)
Perfluorotridecanoic acid (PFTrDA)
Perfluoroundecanoic acid (PFUdA, PFUnA, PFUnDA)

Process

The EPA developed the lists after a multi-year process that included review of the scientific literature for
contaminants measured in species of fish and shellfish that can be found in U.S., analysis of the data, and
external peer review.

Literature Search. The EPA performed a literature search to identify contaminants that bioaccumulate in fish
and shellfish and their corresponding concentrations. After searching multiple databases using a specified set of
search terms, the EPA screened articles to remove any that contained species not found in U.S. waters or

Page 3 of 4


-------
contained concentration data from dosing in laboratory studies. The EPA extracted concentrations of
contaminants in fish and shellfish from the papers and toxicity information (e.g., reference dose and cancer
slope factor) for contaminants from sources such as EPA's Integrated Risk Information System and DHHS' Agency
for Toxic Substances and Disease Registry.

Analysis of Data. A contaminant's presence in fish or shellfish does not necessarily indicate a human health risk
exists. The EPA used each contaminant's concentration and toxicity information in advisory equations found in
EPA's Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories to determine if the levels
found in fish or shellfish would exceed thresholds for safely eating eight ounces of seafood per week, as
recommended by the Dietary Guidelines for Americans, or thresholds for frequent eaters, who were assumed to
eat five ounces of seafood per day. Those contaminants whose levels were found to exceed the thresholds are
included in Table 1.

Not all the contaminants found in fish and shellfish had toxicity information available. For the contaminants
without toxicity values, the EPA calculated a generic screening level for each group of contaminants to capture
contaminants with fish tissue concentrations high enough to potentially be a human health concern. Those
contaminants whose levels potentially could exceed thresholds for safely eating eight ounces of seafood per
week are included in Table 2.

Peer Review. The EPA solicited external peer review of the literature review, analysis, and results by a set of
independent subject matter experts in toxicology and human health risk assessment. The EPA analyzed all the
peer reviewers' comments and recommendations and made some changes in response to their evaluations.

Where can I find more information?

Information on understanding fish advisories: https://www.epa.gov/choose-fish-and-shellfish-wiselv

Information on developing fish advisories: https://www.epa.gov/choose-fish-and-shellfish-wiselv/epa-guidance-
developing-fish-advisories

Information on what was submitted to peer review, peer reviewer comments, and actions taken in response to
the peer review: https://www.epa.gov/choose-fish-and-shellfish-wiselv/epa-guidance-developing-fish-advisories

Page 4 of 4


-------