Chronic Toxicity to Freshwater Organisms
40 CFR 136.3, Table I–A.This manual describes four- to seven-day methods for estimating the chronic toxicity of effluents and receiving waters to three species. The methods are approved under Clean Water Act section 304(h) and specified at
The complete manual and individual method documents are provided. The individual methods are included in the manual.
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Whole Effluent Toxicity Methods Errata Sheet (PDF)(28 pp, 534 K,
Corrections and clarifications to three WET methods manuals; promulgated as part of the 2017 Clean Water Act Methods Update Rule (August 28, 2017).
- Errata for Chronic Freshwater WET Methods Manual (4th edition, 2002) (PDF)(1 pg, 124 K, 2010)
- Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms; 4th ed. (PDF)(350 pp, 5 MB, October 2002, 821-R-02-013)
- 1000.0: Fathead Minnow, Pimephales promelas, Larval Survival and Growth; Chronic Toxicity Test (PDF)(60 pp, 1 MB, October 2002)
- 1001.0: Fathead Minnow, Pimephales promelas, Larval Survival and Teratogenicity Test; Chronic Toxicity (PDF)(30 pp, 536 K, October 2002)
- 1002.0: Daphnid, Ceriodaphnia dubia, Survival and Reproduction Test; Chronic Toxicity (PDF)(57 pp, 911 K, October 2002)
- 1003.0: Green Alga, Selenastrum capricornutum, Growth Test; Chronic Toxicity (PDF)(35 pp, 614 K, October 2002)