National Recommended Water Quality Criteria - Aquatic Life Criteria Table

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 below lists EPA'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

Aquatic Life Criteria
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 See 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 cannot be lower than 25% of the natural level.
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 6.5 – 9.0 7429905 750 87 1988 This value for aluminum is expressed in terms of total recoverable metal in the water column.
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.  See Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.

Atrazine 1912249            
Bacteria 1986 See Quality Criteria for Water, 1986 ("Gold Book") for narative statement.
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 See Quality Criteria for Water, 1986 ("Gold Book") for narative statement.
Cadmium (P) 7440439 1.8 0.72 33 7.9 2016

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.  See 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 1986  
Chlorine 7782505 19 11 13 7.5 1986  
Chloropyrifos 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.  See 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.  See Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.
Color 1986 See Quality Criteria for Water, 1986 ("Gold Book") for narative 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.  See 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 See Quality Criteria for Water, 1986 ("Gold Book") for narative statement.
Guthion 86500 0.01 0.01 1986 The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level.
Hardness 1986 See Quality Criteria for Water, 1986 ("Gold Book") for narative 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 The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level.
Lead (P) 7439921 65 2.5 210 8.1 1980

Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column.  See 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 The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level.
Mercury Methylmercury (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.  See Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria.

Methoxychlor 72435 0.03 0.03 1986 The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level.
Methyl Tertiary-Butyl Ether (MTBE)              
Mirex 2385855 0.001 0.001 1986 The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level.
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.  See 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 See EPA's Ecoregional criteria for Total Phosphorus, Total Nitrogen, Chlorophyll a and Water Clarity (Secchi depth for lakes; turbidity for streams and rivers) (& Level III Ecoregional criteria)
Oil and Grease 1986 See Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Oxygen, Dissolved Freshwater
Oxygen, Dissolved Saltwater
7782447 1986 See Quality Criteria for Water, 1986 ("Gold Book") for freshwater. For saltwater, see 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.
pH 6.5 – 9 6.5 – 8.5 1986

The CCC of 20mg/L is a minimum value except where alkalinity is naturally lower, in which case the criterion cannot be lower than 25% of the natural level.

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

See Aquatic Life Ambient Water Quality Criterion for Selenium -Freshwater 2016 for narrative statement.
Silver (P) 7440224 3.2 1.9 1980  
Solids Suspended and Turbidity 1986 See Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Sulfide-Hydrogen Sulfide 7783064 2.0 2.0 1986  
Tainting Substances 1986 See Quality Criteria for Water, 1986 ("Gold Book") for narrative statement.
Temperature 1986 Criteria is species dependent. See 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  
4,4'-DDT (P) 50293 1.1 0.001 0.13 0.001 1980  

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)
CMC CCC
Cadmium 1.0166 -3.924 0.7409 -4.719 1.136672-[(lnhardness)(0.041838)] 1.101672-[(lnhardness)(0.041838)]
Chromium III 0.8190 3.7256 0.8190 0.6848 0.316 0.860
Copper 0.9422 -1.700 0.8545 -1.702 0.960 0.960
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-dependant 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

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