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Marine Environmental Update Bulletin

September 27, 2001: EPA Drafts Aquatic Life Criteria, Ecorisk Assessment for Atrazine

On September 26, 2001, the Environmental Protection Agency announced the availability if its draft aquatic life criteria document for atrazine developed under Section 304(a)(1) of the Clean Water Act (CWA). The EPA is soliciting views from the public on issues of science pertaining to the information used in deriving the draft criteria. The EPA is also soliciting input from the public on harmonizing risk assesssment methods used by the Office of Water (OW) in its draft aquatic life criteria document for atrazine and by the Office of Pesticide Programs (OPP) in its Preliminary Ecological Fate and Effects Risk Assessment for Atrazine, released simultaneously.

Atrazine is moderately volatile and soluble in water, and resistant to natural degradation in water. Because of atrazine's chemical properties and widespread use as an herbicide, concerns have been raised over the potential risks posed by exposure of aquatic organisms to it. The EPA has developed the following water quality criteria:

Freshwater

• One-hour average concentration not to exceed 350 µg/l more than once every three years on the average (Acute Criterion); and
• Four-day average concentration not to exceed 12 µg/l more than once every three years on the average (Chronic Criterion).

Saltwater

• One hour average concentration not to exceed 760 µg/l more than once every three years on the average (Acute Criterion); and
• Four-day average concentration not to exceed 26 µg/l more than once every three years on the average (Chronic Criterion).

The preliminary risk assessment was developed as part of the EPA's process for making reregistration eligibility decisions for the organophosphate and other pesticides and for tolerance reassessments consistent with the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 1996 (FQPA). The EPA's preliminary ecological fate and effects risk assessment and other related documents for atrazine are available in the individual pesticide dockets. On February 14, 2001 (66 FR 10287) (FRL-6765-3), the EPA released the preliminary human health risk assessment and related documents for atrazine through the docket. As additional comments, reviews, and risk assessment modifications become available, these will also be docketed for atrazine.

Comments on either document are due within 60 days of the Federal Register notice publication date. The complete texts of the notices, including points of contact, deadlines, and information on obtaining the draft documents, are available from MESO.

Federal Register, Volume 66, Number 187, Wednesday, September 26, 2001, pp. 49186-49188 (text only, 43.1 KB Adobe™ Acrobat™ file).

Federal Register, Volume 66, Number 187, Wednesday, September 26, 2001, pp. 49180–49182 (text only, 42.1 KB Adobe™ Acrobat™ file).