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Current

National Recommended Water Quality Criteria

EPA's compilation of national recommended water quality criteria is presented as a summary table containing recommended water quality criteria for the protection of aquatic life and human health in surface water for approximately 150 pollutants. These criteria are published pursuant to Section 304(a) of the Clean Water Act (CWA) and provide guidance for states and tribes to use in adopting water quality standards.


Priority Pollutants

    Freshwater Saltwater Human Health for the consumption of  
Priority Pollutant CAS Number CMC 1 
(acute)
(µg/L)
CCC 1 
(chronic)
(µg/L)
CMC 1 
(acute)
(µg/L)
CCC 1 
(chronic)
(µg/L)
Water + Organism
(µg/L)
Organism Only
(µg/L)
FR Cite/
Source
1 Antimony 7440360



5.6 B 640 B 65 FR 66443
2 Arsenic 7440382 340 A,D,K 150 A,D,K 69 A,D,bb 36 A,D,bb 0.018 C,M,S 0.14 C,M,S 65 FR 31682
57 FR 60848
3 Beryllium 7440417



Z   65 FR 31682
4 Cadmium 7440439 2.0 D,E,K,bb 0.25 D,E,K,bb 40 D,bb 8.8 D,bb Z   EPA 822-R-01-001
65 FR 31682
5a Chromium (III) 16065831 570 D,E,K 74 D,E,K     Z Total   EPA 820-B-96-001
65 FR 31682
5b Chromium (VI) 18540299 16 D,K 11 D,K 1,100 D,bb 50 D,bb Z Total   65 FR 31682
6 Copper 7440508 Freshwater criteria calculated using the BLM mm - See Document 4.8 D,cc,ff 3.1 D,cc,ff 1,300 U   EPA-822-R-07-001 (PDF)(204 pp, 910 K)
65 FR 31682
72 FR 7983
7 Lead 7439921 65 D,E,bb,gg 2.5 D,E,bb,gg 210 D,bb 8.1 D,bb     65 FR 31682
8a

8b

Mercury

Methylmercury

7439976

22967926

1.4 D,K,hh

 

0.77 D,K,hh

 

1.8 D,ee,hh

 

0.94 D,ee,hh

 


 

0.3 mg/kg J

62 FR 42160

EPA 823-R-01-001

9 Nickel 7440020 470 D,E,K 52 D,E,K 74 D,bb 8.2 D,bb 610 B 4,600 B 65 FR 31682
10 Selenium 7782492 L,R,T 5.0 T 290 D,bb,dd 71 D,bb,dd 170 Z 4200 62 FR 42160
65 FR 31682
65 FR 66443
11 Silver 7440224 3.2 D,E,G   1.9 D,G       65 FR 31682
12 Thallium 7440280         0.24 0.47 68 FR 75510
13 Zinc 7440666 120 D,E,K 120 D,E,K 90 D,bb 81 D,bb 7,400 U 26,000 U 65 FR 31682
65 FR 66443
14 Cyanide 57125 22 K,Q 5.2 K,Q 1 Q,bb 1 Q,bb 140 jj 140 jj EPA 820-B-96-001
57 FR 60848
68 FR 75510
15 Asbestos 1332214         7 million fibers/L I   57 FR 60848
16 2,3,7,8-TCDD (Dioxin) 1746016         5.0E-9 C 5.1E-9 C 65 FR 66443
17 Acrolein 107028 3ug/L 3ug/L     6 ll 9 ll 74 FR 27535
18 Acrylonitrile 107131         0.051 B,C 0.25 B,C 65 FR 66443
19 Benzene 71432         2.2 B,C 51 B,C IRIS 01/19/00
65 FR 66443
20 Bromoform 75252         4.3 B,C 140 B,C 65 FR 66443
21 Carbon Tetrachloride 56235         0.23 B,C 1.6 B,C 65 FR 66443
22 Chlorobenzene 108907         130 Z,U 1,600 U 68 FR 75510
23 Chlorodibromomethane 124481         0.40 B,C 13 B,C 65 FR 66443
24 Chloroethane 75003              
25 2-Chloroethylvinyl Ether 110758              
26 Chloroform 67663         5.7 C,P 470 C,P 62 FR 42160
27 Dichlorobromomethane 75274         0.55 B,C 17 B,C 65 FR 66443
28 1,1-Dichloroethane 75343              
29 1,2-Dichloroethane 107062         0.38 B,C 37 B,C 65 FR 66443
30 1,1-Dichloroethylene 75354         330 7,100 68 FR 75510
31 1,2-Dichloropropane 78875         0.50 B,C 15 B,C 65 FR 66443
32 1,3-Dichloropropene 542756         0.34 C 21 C 68 FR 75510
33 Ethylbenzene 100414         530 2,100 68 FR 75510
34 Methyl Bromide 74839         47 B 1,500 B 65 FR 66443
35 Methyl Chloride 74873          
65 FR 31682
36 Methylene Chloride 75092         4.6 B,C 590 B,C 65 FR 66443
37 1,1,2,2-Tetrachloroethane 79345         0.17 B,C 4.0 B,C 65 FR 66443
38 Tetrachloroethylene 127184         0.69 C 3.3 C 65 FR 66443
39 Toluene 108883         1,300 Z 15,000 68 FR 75510
40 1,2-Trans-Dichloroethylene 156605         140 Z 10,000 68 FR 75510
41 1,1,1-Trichloroethane 71556         Z   65 FR 31682
42 1,1,2-Trichloroethane 79005         0.59 B,C 16 B,C 65 FR 66443
43 Trichloroethylene 79016         2.5 C 30 C 65 FR 66443
44 Vinyl Chloride 75014         0.025 C,kk 2.4 C,kk 68 FR 75510
45 2-Chlorophenol 95578         81 B,U 150 B,U 65 FR 66443
46 2,4-Dichlorophenol 120832         77 B,U 290 B,U 65 FR 66443
47 2,4-Dimethylphenol 105679         380 B 850 B,U 65 FR 66443
48 2-Methyl-4,6-Dinitrophenol 534521         13 280 65 FR 66443
49 2,4-Dinitrophenol 51285         69 B 5,300 B 65 FR 66443
50 2-Nitrophenol 88755              
51 4-Nitrophenol 100027              
52 3-Methyl-4-Chlorophenol 59507         U U  
53 Pentachlorophenol 87865 19 F,K 15 F,K 13 bb 7.9 bb 0.27 B,C 3.0 B,C,H 65 FR 31682
65 FR 66443
54 Phenol 108952         10,000 ll,U 860,000 ll,U 74 FR 27535
55 2,4,6-Trichlorophenol 88062         1.4 B,C 2.4 B,C,U 65 FR 66443
56 Acenaphthene 83329         670 B,U 990 B,U 65 FR 66443
57 Acenaphthylene 208968              
58 Anthracene 120127         8,300 B 40,000 B 65 FR 66443
59 Benzidine 92875         0.000086 B,C 0.00020 B,C 65 FR 66443
60 Benzo(a) Anthracene 56553         0.0038 B,C 0.018 B,C 65 FR 66443
61 Benzo(a) Pyrene 50328         0.0038 B,C 0.018 B,C 65 FR 66443
62 Benzo(b) Fluoranthene 205992         0.0038 B,C 0.018 B,C 65 FR 66443
63 Benzo(ghi) Perylene 191242              
64 Benzo(k) Fluoranthene 207089         0.0038 B,C 0.018 B,C 65 FR 66443
65 Bis(2-Chloroethoxy) Methane 111911              
66 Bis(2-Chloroethyl) Ether 111444         0.030 B,C 0.53 B,C 65 FR 66443
67 Bis(2-Chloroisopropyl) Ether 108601         1,400 B 65,000 B 65 FR 66443
68 Bis(2-Ethylhexyl) PhthalateX 117817         1.2 B,C 2.2 B,C 65 FR 66443
69 4-Bromophenyl Phenyl Ether 101553              
70 Butylbenzyl PhthalateW 85687         1,500 B 1,900 B 65 FR 66443
71 2-Chloronaphthalene 91587         1,000 B 1,600 B 65 FR 66443
72 4-Chlorophenyl Phenyl Ether 7005723              
73 Chrysene 218019         0.0038 B,C 0.018 B,C 65 FR 66443
74 Dibenzo(a,h)Anthracene 53703         0.0038 B,C 0.018 B,C 65 FR 66443
75 1,2-Dichlorobenzene 95501         420 1,300 68 FR 75510
76 1,3-Dichlorobenzene 541731         320 960 65 FR 66443
77 1,4-Dichlorobenzene 106467         63 190 68 FR 75510
78 3,3'-Dichlorobenzidine 91941         0.021 B,C 0.028 B,C 65 FR 66443
79 Diethyl PhthalateW 84662         17,000 B 44,000 B 65 FR 66443
80 Dimethyl PhthalateW 131113         270,000 1,100,000 65 FR 66443
81 Di-n-Butyl PhthalateW 84742         2,000 B 4,500 B 65 FR 66443
82 2,4-Dinitrotoluene 121142         0.11 C 3.4 C 65 FR 66443
83 2,6-Dinitrotoluene 606202              
84 Di-n-Octyl Phthalate 117840              
85 1,2-Diphenylhydrazine 122667         0.036 B,C 0.20 B,C 65 FR 66443
86 Fluoranthene 206440         130 B 140 B 65 FR 66443
87 Fluorene 86737         1,100 B 5,300 B 65 FR 66443
88 Hexachlorobenzene 118741         0.00028 B,C 0.00029 B,C 65 FR 66443
89 Hexachlorobutadiene 87683         0.44 B,C 18 B,C 65 FR 66443
90 Hexachlorocyclopentadiene 77474         40 U 1,100 U 68 FR 75510
91 Hexachloroethane 67721         1.4 B,C 3.3 B,C 65 FR 66443
92 Ideno(1,2,3-cd)Pyrene 193395         0.0038 B,C 0.018 B,C 65 FR 66443
93 Isophorone 78591         35 B,C 960 B,C 65 FR 66443
94 Naphthalene 91203              
95 Nitrobenzene 98953         17 B 690 B,H,U 65 FR 66443
96 N-Nitrosodimethylamine 62759         0.00069 B,C 3.0 B,C 65 FR 66443
97 N-Nitrosodi-n-Propylamine 621647         0.0050 B,C 0.51 B,C 65 FR 66443
98 N-Nitrosodiphenylamine 86306         3.3 B,C 6.0 B,C 65 FR 66443
99 Phenanthrene 85018              
100 Pyrene 129000         830 B 4,000 B 65 FR 66443
101 1,2,4-Trichlorobenzene 120821         35 70 68 FR 75510
102 Aldrin 309002 3.0 G   1.3 G   0.000049
B,C
0.000050 B,C 65 FR 31682
65 FR 66443
103 alpha-BHC 319846         0.0026 B,C 0.0049 B,C 65 FR 66443
104 beta-BHC 319857         0.0091 B,C 0.017 B,C 65 FR 66443
105 gamma-BHC (Lindane) 58899 0.95 K   0.16 G   0.98 1.8 65 FR 31682
68 FR 75510
106 delta-BHC 319868              
107 Chlordane 57749 2.4 G 0.0043 G,aa 0.09 G 0.004 G,aa 0.00080 B,C 0.00081 B,C 65 FR 31682
65 FR 66443
108 4,4'-DDT 50293 1.1 G,ii 0.001 G,aa,ii 0.13 G,ii 0.001 G,aa,ii 0.00022 B,C 0.00022 B,C 65 FR 31682
65 FR 66443
109 4,4'-DDE 72559         0.00022 B,C 0.00022 B,C 65 FR 66443
110 4,4'-DDD 72548         0.00031 B,C 0.00031 B,C 65 FR 66443
111 Dieldrin 60571 0.24 K 0.056 K,O 0.71 G 0.0019 G,aa 0.000052 B,C 0.000054 B,C 65 FR 31682
65 FR 66443
112 alpha-Endosulfan 959988 0.22 G,Y 0.056 G,Y 0.034 G,Y 0.0087 G,Y 62 B 89 B 65 FR 31682
65 FR 66443
113 beta-Endosulfan 33213659 0.22 G,Y 0.056 G,Y 0.034 G,Y 0.0087 G,Y 62 B 89 B 65 FR 31682
65 FR 66443
114 Endosulfan Sulfate 1031078         62 B 89 B 65 FR 66443
115 Endrin 72208 0.086 K 0.036 K,O 0.037 G 0.0023 G,aa 0.059 0.060 65 FR 31682
68 FR 75510
116 Endrin Aldehyde 7421934         0.29 B 0.30 B,H 65 FR 66443
117 Heptachlor 76448 0.52 G 0.0038 G,aa 0.053 G 0.0036 G,aa 0.000079 B,C 0.000079 B,C 65 FR 31682
65 FR 66443
118 Heptachlor Epoxide 1024573 0.52 G,V 0.0038 G,V,aa 0.053 G,V 0.0036 G,V,aa 0.000039 B,C 0.000039 B,C 65 FR 31682
65 FR 66443
119 Polychlorinated Biphenyls (PCBs)     0.014 N,aa   0.03 N,aa 0.000064 B,C,N 0.000064 B,C,N 65 FR 31682
65 FR 66443
120 Toxaphene 8001352 0.73 0.0002 aa 0.21 0.0002 aa 0.00028 B,C 0.00028 B,C 65 FR 31682
65 FR 66443

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Footnotes

A This recommended water quality criterion was derived from data for arsenic (III), but is applied here to total arsenic, which might imply that arsenic (III) and arsenic (V) are equally toxic to aquatic life and that their toxicities are additive. In the arsenic criteria document (PDF) (74 pp, 3.2 MB) (EPA 440/5-84-033, January 1985), Species Mean Acute Values are given for both arsenic (III) and arsenic (V) for five species and the ratios of the SMAVs for each species range from 0.6 to 1.7. Chronic values are available for both arsenic (III) and arsenic (V) for one species; for the fathead minnow, the chronic value for arsenic (V) is 0.29 times the chronic value for arsenic (III). No data are known to be available concerning whether the toxicities of the forms of arsenic to aquatic organisms are additive.

B This criterion has been revised to reflect The Environmental Protection Agency's q1* or RfD, as contained in the Integrated Risk Information System (IRIS) as of May 17, 2002. The fish tissue bioconcentration factor (BCF) from the 1980 Ambient Water Quality Criteria document was retained in each case.

C This criterion is based on carcinogenicity of 10-6 risk. Alternate risk levels may be obtained by moving the decimal point (e.g., for a risk level of 10-5, move the decimal point in the recommended criterion one place to the right).

D Freshwater and saltwater criteria for metals are expressed in terms of the dissolved metal in the water column. The recommended water quality criteria value was calculated by using the previous 304(a) aquatic life criteria expressed in terms of total recoverable metal, and multiplying it by a conversion factor (CF). The term "Conversion Factor" (CF) represents the recommended conversion factor for converting a metal criterion expressed as the total recoverable fraction in the water column to a criterion expressed as the dissolved fraction in the water column. (Conversion Factors for saltwater CCCs are not currently available. Conversion factors derived for saltwater CMCs have been used for both saltwater CMCs and CCCs). See "Office of Water Policy and Technical Guidance on Interpretation and Implementation of Aquatic Life Metals Criteria (PDF)," (49 pp, 3MB) October 1, 1993, by Martha G. Prothro, Acting Assistant Administrator for Water, available from the Water Resource center and 40CFR§131.36(b)(1). Conversion Factors applied in the table can be found in Appendix A to the Preamble- Conversion Factors for Dissolved Metals.

E The freshwater criterion for this metal is expressed as a function of hardness (mg/L) in the water column. The value given here corresponds to a hardness of 100 mg/L. Criteria values for other hardness may be calculated from the following: CMC (dissolved) = exp{mA [ln(hardness)]+ bA} (CF), or CCC (dissolved) = exp{mC [ln (hardness)]+ bC} (CF) and the parameters specified in Appendix B- Parameters for Calculating Freshwater Dissolved Metals Criteria That Are Hardness-Dependent.

F Freshwater aquatic life values for pentachlorophenol are expressed as a function of pH, and are calculated as follows: CMC = exp(1.005(pH)-4.869); CCC = exp(1.005(pH)-5.134). Values displayed in table correspond to a pH of 7.8.

G This Criterion is based on 304(a) aquatic life criterion issued in 1980, and was issued in one of the following documents: Aldrin/Dieldrin (PDF) (153 pp, 7.3 MB) (EPA 440/5-80-019), Chlordane (PDF) (68 pp, 3.1 MB) (EPA 440/5-80-027), DDT (PDF) (175 pp, 8.3 MB) (EPA 440/5-80-038), Endosulfan (PDF) (155 pp, 7.3 MB) (EPA 440/5-80-046), Endrin (PDF) (103 pp, 4.6 MB) (EPA 440/5-80-047), Heptachlor (PDF) (114 pp, 5.4 MB) (EPA 440/5-80-052), Hexachlorocyclohexane (PDF) (109 pp, 4.8 MB) (EPA 440/5-80-054), Silver (EPA 440/5-80-071). The Minimum Data Requirements and derivation procedures were different in the 1980 Guidelines than in the 1985 Guidelines (PDF) (104 pp, 3.3 MB) . For example, a "CMC" derived using the 1980 Guidelines was derived to be used as an instantaneous maximum. If assessment is to be done using an averaging period, the values given should be divided by 2 to obtain a value that is more comparable to a CMC derived using the 1985 Guidelines.

H No criterion for protection of human health from consumption of aquatic organisms excluding water was presented in the 1980 criteria document or in the 1986 Quality Criteria for Water. Nevertheless, sufficient information was presented in the 1980 document to allow the calculation of a criterion, even though the results of such a calculation were not shown in the document.

I This criterion for asbestos is the Maximum Contaminant Level (MCL) developed under the Safe Drinking Water Act (SDWA).

J This fish tissue residue criterion for methylmercury is based on a total fish consumption rate of 0.0175 kg/day.

K This recommended criterion is based on a 304(a) aquatic life criterion that was issued in the 1995 Updates: Water Quality Criteria Documents for the Protection of Aquatic Life in Ambient Water, (EPA 820-B-96-001, September 1996). This value was derived using the GLI Guidelines (60 FR 15393-15399, March 23, 1995; 40CFR132 Appendix A); the difference between the 1985 Guidelines and the GLI Guidelines are explained on page iv of the 1995 Updates. None of the decisions concerning the derivation of this criterion were affected by any considerations that are specific to the Great Lakes.

L The CMC = 1/[(f1/CMC1) + (f2/CMC2)] where f1 and f2 are the fractions of total selenium that are treated as selenite and selenate, respectively, and CMC1 and CMC2 are 185.9 g/l and 12.82 g/l, respectively.

M EPA is currently reassessing the criteria for arsenic.

N This criterion applies to total pcbs, (e.g., the sum of all congener or all isomer or homolog or Aroclor analyses.)

O The derivation of the CCC for this pollutant (Endrin) did not consider exposure through the diet, which is probably important for aquatic life occupying upper trophic levels.

P Although a new RfD is available in IRIS, the surface water criteria will not be revised until the National Primary Drinking Water Regulations: Stage 2 Disinfectants and Disinfection Byproducts Rule (Stage 2 DBPR) is completed, since public comment on the relative source contribution (RSC) for chloroform is anticipated.

Q This recommended water quality criterion is expressed as g free cyanide (as CN)/L.

R This value for selenium was announced (61 FR 58444-58449, November 14, 1996) as a proposed GLI 303(c) aquatic life criterion. EPA is currently working on this criterion and so this value might change substantially in the near future.

S This recommended water quality criterion for arsenic refers to the inorganic form only.

T This recommended water quality criterion for selenium is expressed in terms of total recoverable metal in the water column. It is scientifically acceptable to use the conversion factor (0.996- CMC or 0.922- CCC) that was used in the GLI to convert this to a value that is expressed in terms of dissolved metal.

U The organoleptic effect criterion is more stringent than the value for priority toxic pollutants.

V This value was derived from data for heptachlor and the criteria document provides insufficient data to estimate the relative toxicities of heptachlor and heptachlor epoxide.

W Although EPA has not published a completed criteria document for butylbenzyl phthalate it is EPA's understanding that sufficient data exist to allow calculation of aquatic criteria. It is anticipated that industry intends to publish in the peer reviewed literature draft aquatic life criteria generated in accordance with EPA Guidelines. EPA will review such criteria for possible issuance as national WQC.

X There is a full set of aquatic life toxicity data that show that DEHP is not toxic to aquatic organisms at or below its solubility limit.

Y This value was derived from data for endosulfan and is most appropriately applied to the sum of alpha-endosulfan and beta-endosulfan.

Z A more stringent MCL has been issued by EPA. Refer to drinking water regulations (40 CFR 141) or Safe Drinking Water Hotline (1-800-426-4791) for values.

aa This criterion is based on a 304(a) aquatic life criterion issued in 1980 or 1986, and was issued in one of the following documents: Aldrin/Dieldrin (PDF) (153 pp, 7.3 MB) (EPA 440/5-80-019), Chlordane (PDF) (68 pp, 3.1 MB) (EPA 440/5-80-027), DDT (PDF) (175 pp, 8.3 MB) (EPA 440/5-80-038), Endrin (PDF) (103 pp, 4.6 MB) (EPA 440/5-80-047), Heptachlor (PDF) (114 pp, 5.4 MB) (EPA 440/5-80-052), Polychlorinated biphenyls (EPA 440/5-80-068), Toxaphene (EPA 440/5-86-006). This CCC is currently based on the Final Residue Value (FRV) procedure. Since the publication of the Great Lakes Aquatic Life Criteria Guidelines in 1995 (60 FR 15393-15399, March 23, 1995), the Agency no longer uses the Final Residue Value procedure for deriving CCCs for new or revised 304(a) aquatic life criteria. Therefore, the Agency anticipates that future revisions of this CCC will not be based on the FRV procedure.

bb This water quality criterion is based on a 304(a) aquatic life criterion that was derived using the 1985 Guidelines (PDF) (104 pp, 3.3 MB) (Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses, PB85-227049, January 1985) and was issued in one of the following criteria documents: Arsenic (PDF) (74 pp, 3.2 MB) (EPA 440/5-84-033), Cadmium (EPA 822-R-01-001), Chromium (EPA 440/5-84-029), Copper (PDF) (150 pp, 6.2 MB) (EPA 440/5-84-031), Cyanide (PDF) (67 pp, 2.7 MB) (EPA 440/5- 84-028), Lead (EPA 440/5-84-027), Nickel (EPA 440/5-86-004), Pentachlorophenol (EPA 440/5-86-009), Toxaphene, (EPA 440/5-86-006), Zinc (EPA 440/5-87- 003).

cc When the concentration of dissolved organic carbon is elevated, copper is substantially less toxic and use of Water-Effect Ratios might be appropriate.

dd The selenium criteria document (EPA 440/5-87-006, September 1987) provides that if selenium is as toxic to saltwater fishes in the field as it is to freshwater fishes in the field, the status of the fish community should be monitored whenever the concentration of selenium exceeds 5.0 g/L in salt water because the saltwater CCC does not take into account uptake via the food chain.

ee This recommended water quality criterion was derived on page 43 of the mercury criteria document (PDF) (144 pp, 6.4 MB) (EPA 440/5-84-026, January 1985). The saltwater CCC of 0.025 ug/L given on page 23 of the criteria document is based on the Final Residue Value procedure in the 1985 Guidelines. Since the publication of the Great Lakes Aquatic Life Criteria Guidelines in 1995 (60 FR 15393-15399, March 23, 1995), the Agency no longer uses the Final Residue Value procedure for deriving CCCs for new or revised 304(a) aquatic life criteria.

ff This recommended water quality criterion was derived in Ambient Water Quality Criteria Saltwater Copper Addendum (Draft, April 14, 1995) and was promulgated in the Interim final National Toxics Rule (60 FR 22228-222237, May 4, 1995).

gg EPA is actively working on this criterion and so this recommended water quality criterion may change substantially in the near future.

hh This recommended water quality criterion was derived from data for inorganic mercury (II), but is applied here to total mercury. If a substantial portion of the mercury in the water column is methylmercury, this criterion will probably be under protective. In addition, 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.

ii This criterion applies to DDT and its metabolites (i.e., the total concentration of DDT and its metabolites should not exceed this value).

jj This recommended water quality criterion is expressed as total cyanide, even though the IRIS RFD we used to derive the criterion is based on free cyanide. The multiple forms of cyanide that are present in ambient water have significant differences in toxicity due to their differing abilities to liberate the CN-moiety. Some complex cyanides require even more extreme conditions than refluxing with sulfuric acid to liberate the CN-moiety. Thus, these complex cyanides are expected to have little or no 'bioavailability' to humans. If a substantial fraction of the cyanide present in a water body is present in a complexed form (e.g., Fe4[Fe(CN)6]3), this criterion may be over conservative.

kk This recommended water quality criterion was derived using the cancer slope factor of 1.4 (LMS exposure from birth).

ll This criterion has been revised to reflect the Environmental Protection Agency's cancer slope factor (CSF) or reference dose (RfD), as contained in the Integrated Risk Information System (IRIS) as of (date of publication of Final FR Notice). The fish tissue bioconcentration factor (BCF) from the 1980 Ambient Water Quality Criteria document was retained in each case.

mm The available toxicity data, when evaluated using the procedures described in the “Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses” indicate that freshwater aquatic life should be protected if the 24-hour average and four-day average concentrations do not respectively exceed the acute and chronic criteria concentrations calculated by the Biotic Ligand Model.

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Non Priority Pollutants

    Freshwater Saltwater Human Health for the consumption of  
Non Priority Pollutant CAS Number CMC
(acute)
(µg/L)
CCC
(chronic)
(µg/L)
CMC
(acute)
(µg/L)
CCC
(chronic)
(µg/L)
Water + Organism
(µg/L)
Organism Only
(µg/L)
FR Cite/
Source
1 Alkalinity   20000 F         Gold Book
2 Aluminum pH 6.5 – 9.0 7429905 750 I 87 I,L         53 FR 33178
3 Ammonia 7664417 FRESHWATER CRITERIA ARE pH, Temperature and Life-stage DEPENDENT—SEE DOCUMENT D

SALTWATER CRITERIA ARE pH AND TEMPERATURE DEPENDENT

EPA 822-R-99-014
EPA 440-5-88-004 (PDF) (2.1 MB)
4 Aesthetic Qualities NARRATIVE STATEMENT—SEE DOCUMENT Gold Book
5 Bacteria FOR PRIMARY RECREATION AND SHELLFISH USES—SEE DOCUMENT Gold Book
6 Barium 7440393         1,000 A   Gold Book
7 Boron NARRATIVE STATEMENT—SEE DOCUMENT Gold Book
8 Chloride 16887006 860000 G 230000 G         53 FR 19028
9 Chlorine 7782505 19 11 13 7.5 C   Gold Book
10 Chlorophenoxy Herbicide (2,4,5,-TP) 93721         10 A   Gold Book
11 Chlorophenoxy Herbicide (2,4-D) 94757         100 C   Gold Book
12 Chloropyrifos 2921882 0.083 G 0.041 G 0.011 G 0.0056 G     Gold Book
13 Color NARRATIVE STATEMENT—SEE DOCUMENT Gold Book
14 Demeton 8065483   0.1 F   0.1 F     Gold Book
15 Ether, Bis( Chloromethyl) 542881         0.00010 H 0.00029 H 65 FR 66443
16 Gases, Total Dissolved NARRATIVE STATEMENT—SEE DOCUMENT F Gold Book
17 Guthion 86500   0.01 F   0.01 F     Gold Book
18 Hardness NARRATIVE STATEMENT—SEE DOCUMENT Gold Book
19 Hexachlorocyclo-hexane-Technical 608731         0.0123 H 0.0414 H Gold Book
20 Iron 7439896   1000 F     300 A   Gold Book
21 Malathion 121755   0.1 F   0.1 F     Gold Book
22 Manganese 7439965         50 O 100 A Gold Book
23 Methoxychlor 72435   0.03 F   0.03 F 100 A,C   Gold Book
24 Mirex 2385855   0.001 F   0.001 F     Gold Book
25 Nitrates 14797558         10,000 A   Gold Book
26 Nitrosamines         0.0008 1.24 Gold Book
27 Dinitrophenols 25550587         69 5300 65 FR 66443
28 Nonylphenol 84852153 28ug/L 6.6ug/L 7ug/L 1.7ug/L     71 FR 9337
29 Nitrosodibutylamine, N 924163         0.0063 H 0.22 H 65 FR 66443
30 Nitrosodiethylamine, N 55185         0.0008 H 1.24 H Gold Book
31 Nitrosopyrrolidine, N 930552         0.016 H 34 H 65 FR 66443
32 Oil and Grease NARRATIVE STATEMENT—SEE DOCUMENT F Gold Book
33 Oxygen, Dissolved Freshwater
Oxygen, Dissolved Saltwater
7782447 WARMWATER AND COLDWATER MATRIX—SEE DOCUMENT N
SALTWATER—SEE DOCUMENT
Gold Book
EPA 822-R-00-012
34 Diazinon 333415 0.17ug/L 0.17ug/L 0.82ug/L 0.82ug/L     71 FR 9336
35 Parathion 56382 0.065 J 0.013 J         Gold Book
36 Pentachlorobenzene 608935         1.4 E 1.5 E 65 FR 66443
37 pH   6.5 – 9 F   6.5 – 8.5 F,K 5 – 9   Gold Book
38 Phosphorus Elemental 7723140       0.1 F,K     Gold Book
39 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) P
40 Solids Dissolved and Salinity         250,000 A   Gold Book
41 Solids Suspended and Turbidity NARRATIVE STATEMENT—SEE DOCUMENT F Gold Book
42 Sulfide-Hydrogen Sulfide 7783064   2.0 F   2.0 F     Gold Book
43 Tainting Substances NARRATIVE STATEMENT—SEE DOCUMENT Gold Book
44 Temperature SPECIES DEPENDENT CRITERIA—SEE DOCUMENT M Gold Book
45 Tetrachlorobenzene,1,2,4,5- 95943         0.97 E 1.1 E 65 FR 66443
46 Tributyltin (TBT) 0.46 Q 0.072 Q 0.42 Q 0.0074 Q     69 FR 342
47 Trichlorophenol,2,4,5- 95954         1,800 E 3,600 E 65 FR 66443

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Footnotes

A This human health criterion is the same as originally published in the Red Book which predates the 1980 methodology and did not utilize the fish ingestion BCF approach. This same criterion value is now published in the Gold Book.

B The organoleptic effect criterion is more stringent than the value presented in the non priority pollutants table.

C A more stringent Maximum Contaminant Level (MCL) has been issued by EPA under the Safe Drinking Water Act. Refer to drinking water regulations 40CFR141 or Safe Drinking Water Hotline (1-800-426-4791) for values.

D According to the procedures described in the Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses, except possibly where a very sensitive species is important at a site, freshwater aquatic life should be protected if both conditions specified in Appendix C to the Preamble- Calculation of Freshwater Ammonia Criterion are satisfied.

E This criterion has been revised to reflect EPA's q1* or RfD, as contained in the Integrated Risk Information System (IRIS) as of May 17, 2002. The fish tissue bioconcentration factor (BCF) used to derive the original criterion was retained in each case.

F The derivation of this value is presented in the Red Book (EPA 440/9-76-023, July, 1976).

G This value is based on a 304(a) aquatic life criterion that was derived using the 1985 Guidelines (Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Uses, PB85-227049, January 1985) and was issued in one of the following criteria documents: Aluminum (EPA 440/5-86-008); Chloride (EPA 440/5-88-001); Chloropyrifos (EPA 440/5-86-005).

H This criterion is based on carcinogenicity of 10-6 risk. Alternate risk levels may be obtained by moving the decimal point (e.g., for a risk level of 10-5, move the decimal point in the recommended criterion one place to the right).

I This value for aluminum is expressed in terms of total recoverable metal in the water column.

J This value is based on a 304(a) aquatic life criterion that was issued in the 1995 Updates: Water Quality Criteria Documents for the Protection of Aquatic Life in Ambient Water (EPA 820-B-96-001). This value was derived using the GLI Guidelines (60 FR 15393-15399, March 23, 1995; 40CFR132 Appendix A); the differences between the 1985 Guidelines and the GLI Guidelines are explained on page iv of the 1995 Updates. No decision concerning this criterion was affected by any considerations that are specific to the Great Lakes.

K According to page 181 of the Red Book:

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.

L There are three major reasons why the use of Water-Effect Ratios might be appropriate.

  1. The value of 87 µg/l is based on a toxicity test with the striped bass in water with pH = 6.5–6.6 and hardness <10 mg/L. Data in "Aluminum Water-Effect Ratio for the 3M Plant Effluent Discharge, Middleway, West Virginia" (May 1994) indicate that aluminum is substantially less toxic at higher pH and hardness, but the effects of pH and hardness are not well quantified at this time.
  2. In tests with the brook trout at low pH and hardness, effects increased with increasing concentrations of total aluminum even though the concentration of dissolved aluminum was constant, indicating that total recoverable is a more appropriate measurement than dissolved, at least when particulate aluminum is primarily aluminum hydroxide particles. In surface waters, however, the total recoverable procedure might measure aluminum associated with clay particles, which might be less toxic than aluminum associated with aluminum hydroxide.
  3. EPA is aware of field data indicating that many high quality waters in the U.S. contain more than 87 g aluminum/L, when either total recoverable or dissolved is measured.

M U.S. EPA. 1973. Water Quality Criteria 1972. EPA-R3-73-033. National Technical Information Service, Springfield, VA.; U.S. EPA. 1977. Temperature Criteria for Freshwater Fish: Protocol and Procedures. EPA 600/3-77-061. National Technical Information Service, Springfield, VA.

N U.S. EPA. 1986. Ambient Water Quality Criteria for Dissolved Oxygen. EPA 440/5-86-003. National Technical Information Service, Springfield, VA.

O This criterion for manganese is not based on toxic effects, but rather is intended to minimize objectionable qualities such as laundry stains and objectionable tastes in beverages.

P Lakes and Reservoirs in Nutrient Ecoregion: II EPA 822-B-00-007, III EPA 822-B-01-008, IV EPA 822-B-01-009, V EPA 822-B-01-010, VI EPA 822-B-00-008 , VII EPA 822-B-00-009, VIII EPA 822-B-01-015, IX EPA 822-B-00-011, XI EPA 822-B-00-012, XII EPA 822-B-00-013, XIII EPA 822-B-00-014, XIV EPA 822-B-01-011; Rivers and Streams in Nutrient Ecoregion: I EPA 822-B-01-012, II EPA 822-B-00-015, III EPA 822-B-00-016, IV EPA 822-B-01-013, V EPA 822-B-01-014, VI EPA 822-B-00-017, VII EPA 822-B-00-018, VIII EPA 822-B-01-015, IX EPA 822-B-00-019, X EPA 822-B-01-016, XI EPA 822-B-00-020, XII EPA 822-B-00-021, XIV EPA 822-B-00-022; and Wetlands in Nutrient Ecoregion (PDF) (77 pp., 257 K) XIII EPA 822-B-00-023.

Q EPA announced the availability of a draft updated tributyltin (TBT) document on August 7, 1997 (62 FR 42554). The Agency has reevaluated this document and anticipates releasing an updated document for public comment in the near future.

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Organoleptic Effects (e.g., taste and odor)

Pollutant CAS Number Organoleptic Effect Criteria
(µg/L)
FR Cite/
Source
1 Acenaphthene 83329 20 Gold Book
2 Monochlorobenzene 108907 20 Gold Book
3 3-Chlorophenol 0.1 Gold Book
4 4-Chlorophenol 106489 0.1 Gold Book
5 2,3-Dichlorophenol 0.04 Gold Book
6 2,5-Dichlorophenol 0.5 Gold Book
7 2,6-Dichlorophenol 0.2 Gold Book
8 3,4-Dichlorophenol 0.3 Gold Book
9 2,4,5-Trichlorophenol 95954 1 Gold Book
10 2,4,6-Trichlorophenol 88062 2 Gold Book
11 2,3,4,6-Tetrachlorophenol 1 Gold Book
12 2-Methyl-4-Chlorophenol 1800 Gold Book
13 3-Methyl-4-Chlorophenol 59507 3000 Gold Book
14 3-Methyl-6-Chlorophenol 20 Gold Book
15 2-Chlorophenol 95578 0.1 Gold Book
16 Copper 7440508 1000 Gold Book
17 2,4-Dichlorophenol 120832 0.3 Gold Book
18 2,4-Dimethylphenol 105679 400 Gold Book
19 Hexachlorocyclopentadiene 77474 1 Gold Book
20 Nitrobenzene 98953 30 Gold Book
21 Pentachlorophenol 87865 30 Gold Book
22 Phenol 108952 300 Gold Book
23 Zinc 7440666 5000 45 FR79341

Notes:

1. These criteria are based on organoleptic (taste and odor) effects. Because of variations in chemical nomenclature systems, this listing of pollutants does not duplicate the listing in Appendix A of 40 CFR Part 423. Also listed are the Chemical Abstracts Service (CAS) registry numbers, which provide a unique identification for each chemical.

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Additional Notes

  1. Criteria Maximum Concentration and Criterion Continuous Concentration

    The Criteria Maximum Concentration (CMC) is an estimate of the highest concentration of a material in surface water to which an aquatic community can be exposed briefly without resulting in an unacceptable effect. The Criterion Continuous Concentration (CCC) is an estimate of the highest concentration of a material in surface water to which an aquatic community can be exposed indefinitely without resulting in an unacceptable effect. The CMC and CCC are just two of the six parts of an aquatic life criterion; the other four parts are the acute averaging period, chronic averaging period, acute frequency of allowed exceedence, and chronic frequency of allowed exceedence. Because 304(a) aquatic life criteria are national guidance, they are intended to be protective of the vast majority of the aquatic communities in the United States.

  2. Criteria Recommendations for Priority Pollutants, Non Priority Pollutants and Organoleptic Effects

    This compilation lists all priority toxic pollutants and some non priority toxic pollutants, and both human health effect and organoleptic effect criteria issued pursuant to CWA §304(a). Blank spaces indicate that EPA has no CWA §304(a) criteria recommendations. For a number of non-priority toxic pollutants not listed, CWA §304(a) "water + organism" human health criteria are not available, but EPA has published MCLs under the SDWA that may be used in establishing water quality standards to protect water supply designated uses. Because of variations in chemical nomenclature systems, this listing of toxic pollutants does not duplicate the listing in Appendix A of 40 CFR Part 423. Also listed are the Chemical Abstracts Service CAS registry numbers, which provide a unique identification for each chemical.

  3. Human Health Risk

    The human health criteria for the priority and non priority pollutants are based on carcinogenicity of 10-6 risk. Alternate risk levels may be obtained by moving the decimal point (e.g., for a risk level of 10-5, move the decimal point in the recommended criterion one place to the right).

  4. Water Quality Criteria published pursuant to Section 304(a) or Section 303(c) of the CWA

    Many of the values in the compilation were published in the California Toxics Rule. Although such values were published pursuant to Section 303(c) of the CWA, they represent the Agency's most recent calculation of water quality criteria and are thus the Agency's 304(a) criteria.

  5. Calculation of Dissolved Metals Criteria

    The 304(a) criteria for metals, shown as dissolved metals, are calculated in one of two ways. For freshwater metals criteria that are hardness-dependent, the dissolved metal criteria were calculated using a hardness of 100 mg/l as CaCO3 for illustrative purposes only. Saltwater and freshwater metals' criteria that are not hardness-dependent are calculated by multiplying the total recoverable criteria before rounding by the appropriate conversion factors. The final dissolved metals' criteria in the table are rounded to two significant figures. Information regarding the calculation of hardness dependent conversion factors are included in the footnotes.

  6. Maximum Contaminant Levels

    The compilation includes footnotes for pollutants with Maximum Contaminant Levels (MCLs) more stringent than the recommended water quality criteria in the compilation. MCLs for these pollutants are not included in the compilation, but can be found in the appropriate drinking water regulations (40 CFR 141.11-16 and 141.60-63), or can be accessed through the Safe Drinking Water Hotline (800-426-4791) or online.

  7. Organoleptic Effects

    The compilation contains 304(a) criteria for pollutants with toxicity-based criteria as well as non-toxicity based criteria. The basis for the non-toxicity based criteria are organoleptic effects (e.g., taste and odor) which would make water and edible aquatic life unpalatable but not toxic to humans. The table includes criteria for organoleptic effects for 23 pollutants. Pollutants with organoleptic effect criteria more stringent than the criteria based on toxicity (e.g., included in both the priority and non-priority pollutant tables) are footnoted as such.

  8. Gold Book

    The "Gold Book" is Quality Criteria for Water: 1986. EPA 440/5-86-001.

  9. Correction of Chemical Abstract Services Number

    The Chemical Abstract Services number (CAS) for Bis(2-Chlorisoprpyl) Ether, has been revised in IRIS and in the table. The correct CAS number for this chemical is 108-60-1. The previous CAS number for this pollutant was 39638-32-9.

  10. Contaminants with Blanks

    EPA has not calculated criteria for contaminants with blanks. However, permit authorities should address these contaminants in NPDES permit actions using the States' existing narrative criteria for toxics.

  11. Specific Chemical Calculations

    Selenium—Aquatic Life
    This compilation contains aquatic life criteria for selenium that are the same as those published in the proposed CTR. In the CTR, EPA proposed an acute criterion for selenium based on the criterion proposed for selenium in the Water Quality Guidance for the Great Lakes System (61 FR 58444). The GLI and CTR proposals take into account data showing that selenium's two prevalent oxidation states in water, selenite and selenate, present differing potentials for aquatic toxicity, as well as new data indicating that various forms of selenium are additive. The new approach produces a different selenium acute criterion concentration, or CMC, depending upon the relative proportions of selenite, selenate, and other forms of selenium that are present.
    EPA is currently undertaking a reassessment of selenium, and expects the 304(a) criteria for selenium will be revised based on the final reassessment (63 FR 26186). However, until such time as revised water quality criteria for selenium are published by the Agency, the recommended water quality criteria in this compilation are EPA's current 304(a) criteria.

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Appendix A—Conversion Factors for Dissolved Metals

Metal Conversion Factor
freshwater CMC freshwater CCC saltwater CMC saltwater CCC1
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

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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)

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Appendix C - Calculation of Freshwater Ammonia Criterion

  1. The one-hour average concentration of total ammonia nitrogen (in mg N/L) does not exceed, more than once every three years on the average, the CMC (acute criterion) calculated using the following equations:

    • Where salmonid fish are present:
      • CMC = (0.275/(1 + 107.204-pH)) + (39.0/(1 + 10pH-7.204))
    • Or where salmonid fish are not present:
      • CMC = (0.411/(1 + 107.204-pH)) + (58.4/(1 + 10pH-7.204))
    1. The thirty-day average concentration of total ammonia nitrogen (in mg N/L) does not exceed, more than once every three years on theaverage, the CCC (chronic criterion) calculated using the following equations:

      • When fish early life stages are present:
        • CCC = ((0.0577/(1 + 107.688-pH)) + (2.487/(1 + 10pH-7.688))) x MIN (2.85, 1.45·100.028·(25-T))
      • When fish early life stages are absent:
        • CCC = ((0.0577/(1 + 107.688-pH)) + (2.487/(1 + 10pH-7.688))) x 1.45·100.028·(25-MAX(T,7))
    2. In addition, the highest four-day average within the 30-day period should not exceed 2.5 times the CCC.

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The Gold Book

Quality Criteria for Water, 1986 (PDF) (477 pp., 4.6 MB) May 1986

The Red Book

Quality Criteria for Water, 1976 (PDF) (534 pp., 6.2 MB) July 1976

Chemical Specific Criteria Documents from the 1980s

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