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National Recommended Water Quality Criteria - Organoleptic Effects

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 to establish water quality standards and ultimately provide a basis for controlling discharges or releases of pollutants.

Organoleptic Effects (e.g., taste and odor)
Pollutant CAS Number Organoleptic Effect Criteria (µg/L)
Acenaphthene 83329 20
Color NP
Iron 7439896 300
Monochlorobenzene 108907 20
Tainting Substance NP
3-Chlorophenol 0.1
4-Chlorophenol 106489 0.1
2,3-Dichlorophenol 0.04
2,5-Dichlorophenol 0.5
2,6-Dichlorophenol 0.2
3,4-Dichlorophenol 0.3
2,4,5-Trichlorophenol 95954 1
2,4,6-Trichlorophenol 88062 2
2,3,4,6-Tetrachlorophenol 1
2-Methyl-4-Chlorophenol 1800
3-Methyl-4-Chlorophenol 59507 3000
3-Methyl-6-Chlorophenol 20
2-Chlorophenol 95578 0.1
Copper 7440508 1000
2,4-Dichlorophenol 120832 0.3
2,4-Dimethylphenol 105679 400
Hexachlorocyclopentadiene 77474 1
Manganese 7439965  
Nitrobenzene 98953 30
Pentachlorophenol 87865 30
Phenol 108952 300
Zinc 7440666 5000

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 (PDF) (9 pp, 222 K, About PDF)

Source: Quality Criteria for Water, 1986 ("Gold Book") 

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