National Recommended Water Quality Criteria - Aquatic Life Criteria Table

This table contains the most up to date criteria for aquatic life ambient water quality criteria. Aquatic life criteria for toxic chemicals are the highest concentration of specific pollutants or parameters in water that are not expected to pose a significant risk to the majority of species in a given environment or a narrative description of the desired conditions of a water body being "free from" certain negative conditions. The table lists the U.S. Environmental Protection Agency's recommended aquatic life criteria. State and Tribal governments may use these criteria or use them as guidance in developing their own.

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National Recommended Aquatic Life Criteria Table
Appendix A - Conversion Factors for Dissolved Metals
Appendix B - Parameters for Calculating Freshwater Dissolved Metals Criteria That Are Hardness-Dependent

National Recommended Aquatic Life Criteria table

Pollutant (P = Priority Pollutant)	CAS Number	Freshwater CMC¹ (acute) (µg/L)	Freshwater CCC² (chronic) (µg/L)	Saltwater CMC¹ (acute) (µg/L)	Saltwater CCC² (chronic) (µg/L)	Publication Year	Notes
Acrolein (P)	107028	3ug/L	3ug/L	—	—	2009
Aesthetic Qualities	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Aldrin (P)	309002	3.0	—	1.3	—	1980	These criteria are based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.
Alkalinity	—	—	20000	—	—	1986	The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion is the natural alkalinity of the water in question. Where natural alkalinity is > 20 mg/L, the criterion cannot be lower than 25% of the natural level, or 20 mg/L whichever is higher.
alpha-Endosulfan (P)	959988	0.22	0.056	0.034	0.0087	1980	These criteria are based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines. This value was derived from data for endosulfan and is most appropriately applied to the sum of alpha-endosulfan and beta-endosulfan.
Aluminum pH 5.0 - 10.5	7429905	--	--	—	—	2018	The criteria is based on the water chemistry data (for pH, hardness and DOC) entered into the criteria calculator for a given location.
Ammonia	7664417	—	—	—	—	2013 (Freshwater), 1989 (Saltwater)	Freshwater criteria are ph, temperature and life-stage dependent. Saltwater criteria are pH and temperature dependent.
Arsenic	7440382	340	150	69	36	1995	This recommended water quality criterion was derived from data for arsenic (III), but is applied here to total arsenic. Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.
Atrazine	1912249
beta-Endosulfan (P)	33213659	0.22	0.056	0.034	0.0087	1980	These criteria are based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines. This value was derived from data for endosulfan and is most appropriately applied to the sum of alpha-endosulfan and beta-endosulfan.
Boron	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Cadmium (P)	7440439	1.8	vacated	33	7.9	2016	On August 18, 2023, the U.S. District Court for the District of Arizona issued an order vacating EPA’s 2016 national recommended chronic freshwater cadmium aquatic life criterion. EPA is continuing to evaluate the Order. But as a result of that Order, the current national recommended chronic freshwater cadmium aquatic life criterion can be found in EPA’s 2001 Update of Ambient Water Quality Criteria for Cadmium. Freshwater acute and chronic criteria are hardness-dependent and were normalized to a hardness of 100 mg/L as CaCO3 to allow the presentation of representative criteria values. . Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.
Carbaryl	63252	2.1	2.1	1.6	—	2012
Chlordane (P)	57749	2.4	0.0043	0.09	0.004	1980	These criteria are based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.
Chloride	16887006	860000	230000	—	—	1988
Chlorine	7782505	19	11	13	7.5	1986
Chlorpyrifos	2921882	0.083	0.041	0.011	0.0056	1986
Chromium (III) (P)	16065831	570	74	—	—	1995	Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria. The freshwater criterion for this metal is expressed as a function of hardness (mg/L). The value given here corresponds to a hardness of 100 mg/L.
Chromium (VI) (P)	18540299	16	11	1,100	50	1995	Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.
Color	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Copper (P)	7440508	—	—	4.8	3.1	2007	Freshwater criteria calculated using the Biotic Ligand Model. Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.
Cyanide (P)	57125	22	5.2	1	1	1985	These recommended water quality criteria are expressed as µg free cyanide (CN/L).
Demeton	8065483	—	0.1	—	0.1	1985
Diazinon	333415	0.17ug/L	0.17ug/L	0.82ug/L	0.82ug/L	2005
Dieldrin (P)	60571	0.24	0.056	0.71	0.0019	1995	The freshwater CCC criterion and both Saltwater criteria are based are based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.
Endrin (P)	72208	0.086	0.036	0.037	0.0023	1995	The derivation of the CCC for this pollutant did not consider exposure through the diet, which is probably important for aquatic life occupying upper trophic levels.
gamma-BHC (Lindane) (P)	58899	0.95	—	0.16	—	1995	The Saltwater CCC criterion is based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.
Gases, Total Dissolved	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Guthion	86500	—	0.01	—	0.01	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Hardness	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Heptachlor (P)	76448	0.52	0.0038	0.053	0.0036	1980	These criteria are based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.
Heptachlor Epoxide (P)	1024573	0.52	0.0038	0.053	0.0036	1981	These criteria are based on the 1980 criteria which used different Minimum Data Requirements and derivation procedures from the 1985 Guidelines. If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines. This value was derived from data for heptachlor and there was insufficient data to determine relative toxicities of heptachlor and heptachlor epoxide.
Iron	7439896	—	1000	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Lead (P)	7439921	65	2.5	210	8.1	1984	Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria. The freshwater criterion for this metal is expressed as a function of hardness (mg/L). The value given here corresponds to a hardness of 100 mg/L.
Malathion	121755	—	0.1	—	0.1	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Mercury * (P)	7439976 22967926	1.4	0.77	1.8	0.94	1995	Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.
Methoxychlor	72435	—	0.03	—	0.03	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Methyl Tertiary-Butyl Ether (MTBE)
Mirex	2385855	—	0.001	—	0.001	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Nickel (P)	7440020	470	52	74	8.2	1995	Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria. The freshwater criterion for this metal is expressed as a function of hardness (mg/L). The value given here corresponds to a hardness of 100 mg/L.
Nonylphenol	84852153	28 ug/L	6.6 ug/L	7 ug/L	1.7 ug/L	2005
Nutrients	—	—	—	—	—	—	Refer to EPA'S nutrient criteria by waterbody type.
Oil and Grease	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Oxygen, Dissolved Freshwater Oxygen, Dissolved Saltwater	7782447	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for freshwater. For saltwater, Refer to Aquatic Life Criteria for Dissolved Oxygen (Saltwater) Cape Cod to Cape Hatteras.
Parathion	56382	0.065	0.013	—	—	1995
Pentachlorophenol (P)	87865	19	15	13	7.9	1995	Freshwater aquatic life values for pentachlorophenol are expressed as a function of pH and values displayed in table correspond to a pH of 7.8.
Perfluorooctanoic Acid (PFOA)	45285-51-6; 335-67-1; 3825-26-1	3,100	100 in water 1.18 mg/kg Wet Weight in Invertebrate Whole-Body Tissue 6.49 mg/kg Wet Weight Fish Whole-Body Tissue 0.133 mg/kg Wet Weight Fish Muscle Tissue	7000	—	2024	The chronic freshwater-based and chronic tissue-based criteria are independently applicable and no one criterion takes primacy. The value listed as the saltwater CMC represents a benchmark value, not a criterion. Data limitations precluded the development of a CCC in saltwater.
Perfluorooctane Sulfonate (PFOS)	45298-90-6; 1763-23-1; 2795-39-3; 56773-42-3; 4021-47-0; 29457-72-5	71	0.25 in water 0.028 mg/kg Wet Weight in Invertebrate Whole-Body Tissue 0.201 mg/kg Wet Weight in Fish Whole-Body Tissues 0.087 mg/kg Wet Weight in Fish Muscle Tissue	550	—	2024	The chronic freshwater-based and chronic tissue-based criteria are independently applicable and no one criterion takes primacy. The value listed as the saltwater CMC represents a benchmark value, not a criterion. Data limitations precluded the development of a CCC in saltwater.
pH	—	—	6.5 – 9	—	6.5 – 8.5	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement. For open ocean waters where the depth is substantially greater than the euphotic zone, the pH should not be changed more than 0.2 units from the naturally occurring variation or any case outside the range of 6.5 to 8.5. For shallow, highly productive coastal and estuarine areas where naturally occurring pH variations approach the lethal limits of some species, changes in pH should be avoided but in any case should not exceed the limits established for fresh water, i.e., 6.5-9.0.
Phosphorus Elemental	7723140	—	—	—	—	1986
Polychlorinated Biphenyls (PCBs) (P)	—	—	0.014	—	0.03	—	This criterion applies to total PCBs, (e.g., the sum of all congener or all isomer or homolog or Aroclor analyses.)
Selenium (P)	7782492	—	---	290	71	2016 Freshwater 1999 Saltwater	Refer to Aquatic Life Ambient Water Quality Criterion for Selenium - Freshwater 2016 for narrative statement.
Silver (P)	7440224	3.2	—	1.9	—	1980	If evaluation is to be done using an averaging period, the acute criteria values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.
Solids Suspended and Turbidity	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Sulfide-Hydrogen Sulfide	7783064	—	2.0	—	2.0	1986
Tainting Substances	—	—	—	—	—	1986	Refer to Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Temperature	—	—	—	—	—	1986	Criteria is species dependent. Refer to Quality Criteria for Water, 1986 ("Gold Book").
Toxaphene (P)	8001352	0.73	0.0002	0.21	0.0002	1986
Tributyltin (TBT)	—	0.46	0.072	0.42	0.0074	2004
Zinc (P)	7440666	120	120	90	81	1995	Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. Refer to Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria. The freshwater criterion for this metal is expressed as a function of hardness (mg/L). The value given here corresponds to a hardness of 100 mg/L.
4,4'-DDT (P)	50293	1.1	0.001	0.13	0.001	1980

* It is important to note that the mercury aquatic life criterion includes a caution that it might not be adequately protective of such important fishes as the rainbow trout, coho salmon and bluegill. The criterion was derived from data for inorganic mercury (II), but is applied to total mercury and may be under-protective if a substantial portion of the mercury in the water column is methylmercury. Also, even though inorganic mercury is converted to methylmercury and methylmercury bioaccumulates to a great extent, this criterion does not account for uptake via the food chain because sufficient data were not available when the criterion was derived. In light of these issues, EPA is working on an update to the mercury criterion.

Appendix A

Conversion Factors for Dissolved Metals
Metal	Freshwater CMC	Freshwater CCC	Saltwater CMC	Saltwater CCC
Arsenic	1.000	1.000	1.000	1.000
Cadmium	1.136672-[(ln hardness)(0.041838)]	1.101672-[(ln hardness)(0.041838)]	0.994	0.994
Chromium III	0.316	0.860	—	—
Chromium VI	0.982	0.962	0.993	0.993
Copper	0.960	0.960	0.83	0.83
Lead	1.46203-[(ln hardness)(0.145712)]	1.46203-[(ln hardness)(0.145712)]	0.951	0.951
Mercury	0.85	0.85	0.85	0.85
Nickel	0.998	0.997	0.990	0.990
Selenium	—	—	0.998	0.998
Silver	0.85	—	0.85	—
Zinc	0.978	0.986	0.946	0.946

Appendix B

Parameters for Calculating Freshwater Dissolved Metals Criteria That Are Hardness-Dependent
Chemical	mA	bA	mC	bC	Freshwater Conversion Factors (CF)
Chemical	mA	bA	mC	bC	CMC	CCC
Cadmium³	0.9789	-3.866	—	—	1.136672-[(lnhardness)(0.041838)]	—
Chromium III	0.8190	3.7256	0.8190	0.6848	0.316	0.860
Lead	1.273	-1.460	1.273	-4.705	1.46203-[(lnhardness)(0.145712)]	1.46203-[(lnhardness)(0.145712)]
Nickel	0.8460	2.255	0.8460	0.0584	0.998	0.997
Silver	1.72	-6.59	—	—	0.85	—
Zinc	0.8473	0.884	0.8473	0.884	0.978	0.986

Hardness-dependent metals' criteria may be calculated from the following:

CMC (dissolved) = exp{mA [ln(hardness)]+ bA} (CF)

CCC (dissolved) = exp{mC [ln(hardness)]+ bC} (CF)

1/ CMC: Criterion Maximum Concentration
2/ CCC: Criterion Continuous Concentration
3/ On August 18, 2023, the U.S. District Court for the District of Arizona issued an order vacating EPA’s 2016 national recommended chronic freshwater cadmium aquatic life criterion. EPA is continuing to evaluate the Order. But as a result of that Order, the current national recommended chronic freshwater cadmium aquatic life criterion can be found in EPA’s 2001 Update of Ambient Water Quality Criteria for Cadmium.