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CASRN: 15972608

Update: March 1996

Current Massachusetts Regulatory Limit
MMCL = 0.002 mg/L. ORS has adopted the MCL published by the U.S. EPA. 

Federal Regulatory Limit
The MCL for alachlor is set at the PQL of 0.002 mg/L. FINAL 56 FR 3526 (1/30/91). The MCLG is set at zero (50 FR 46936 (11/13/85)). 

Basis for Criteria
The MCL for alachlor is set as close to the MCLG as possible, considering the ability of public water systems to detect and remove contaminants using suitable treatment technologies.

Critical Effects
An MCLG for alachlor is set at zero based on carcinogenic effects. Alachlor feeding studies have produced carcinogenic effects, including lung tumors in mice, and stomach, thyroid, and nasal turbinate tumors in rats (50 FR 46936 (11/13/85)). 

Cancer Assessment B2
The cancer risk assessment is currently under review by an U.S. EPA workgroup.

Drinking water concentration at 1 x 10-4 cancer risk = 0.04 mg/l (54 FR 22062 (5/22/89)).

Organochlorine Pesticide

Analytical Information
: The PQL used as the basis for the MCL is 0.002 mg/L.

Analytical Methods
U.S. EPA 505, 507 and 525

PQLs and analytical methods may have been updated since this guidance value was last revised. Updated analytical methods for drinking water and their associated PQLs may be found at

Other Regulatory Data
Any Health Advisories, Reference Doses (RfDs), cancer assessments or Cancer Potency Factors (CPFs) referenced in this document pertain to the derivation of the current guidance value. Updated information may be obtained from the following sources:

Health Advisories - The U.S. EPA provides guidance for shorter-term exposures for chemicals based on their non-cancer effects. Current health advisories may be more current than those used to derive MCLs and may be found at

RfDs, cancer assessments and CPFs - For specific information pertaining to derivation of drinking water criteria, consult the Federal Register notice that announces the availability of the most current guidance for that chemical. In addition, information on other current RfDs and CPFs as well as cancer assessments for specific chemicals may be found in the U.S. EPA Integrated Risk Information System (IRIS) at Please note that the information in IRIS may differ from that used in the derivation process as published in the Federal Register notice.

Federal Register. July 25, 1990. Part II. Environmental Protection Agency. 40 Federal Register. November 13, 1985.Part IV. 40 CFR Part 141. National Primary Drinking Water Regulations; Synthetic Organic Chemicals, Inorganic Chemicals and Microorganisms; Proposed Rule. (50 FR 46936).

Federal Register. May 22, 1989.40 CFR parts 141, 142 and 143.National Primary and Secondary Drinking Water Regulations; Proposed Rule.(54 FR 22062).

Federal Register. January 30, 1991. Part II. Environmental Protection Agency. 40 CFR Parts 141, 142, and 143. National Primary Drinking Water Regulations; Final Rule. (56 FR 3526).

Monsanto Company. 1984. MRID No. 00148923. This document is available from EPA.