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Malathion; Revised Reregistration Eligibility Decision

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Information about this document as published in the Federal Register.

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Environmental Protection Agency (EPA).




This notice announces EPA's decision to modify certain risk mitigation measures that were specified in the 2006 Reregistration Eligibility Decision (RED) for the pesticide malathion. EPA conducted this reassessment of the malathion RED in response to public comments received during the comment period and to new data submitted by the technical registrant, Cheminova, Inc. Based on the new information received, and in a continuing effort to mitigate risk, the Agency has made certain modifications to the malathion RED.

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Eric Miederhoff, Special Review and Reregistration Division (7508P), Office of Pesticide Programs, Environmental Protection Agency, 1200 Pennsylvania Start Printed Page 30084Ave., NW., Washington, DC 20460-0001; telephone number: (703) 347-8028; fax number: (703) 308-7070; e-mail address:

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I. General Information

A. Does this Action Apply to Me?

This action is directed to the public in general, and may be of interest to a wide range of stakeholders including environmental, human health, farm worker and agricultural advocates; the chemical industry; pesticide users; and members of the public interested in the sale, distribution, or use of pesticides. Since others also may be interested, the Agency has not attempted to describe all the specific entities that may be affected by this action. If you have any questions regarding the applicability of this action to a particular entity, consult the person listed under FOR FURTHER INFORMATION CONTACT.

B. How Can I Get Copies of this Document and Other Related Information?

1. Docket. EPA has established a docket for this action under docket identification (ID) number EPA-HQ-OPP-2004-0348. Publicly available docket materials are available either in the electronic docket at, or, if only available in hard copy, at the Office of Pesticide Programs (OPP) Regulatory Public Docket in Rm. S-4400, One Potomac Yard (South Bldg.), 2777 S. Crystal Dr., Arlington, VA. The hours of operation of this Docket Facility are from 8:30 a.m. to 4 p.m., Monday through Friday, excluding legal holidays. The Docket Facility telephone number is (703) 305-5805.

2. Electronic access. You may access this Federal Register document electronically through the EPA Internet under the “Federal Register” listings at​fedrgstr.

II. Background

A. What Action is the Agency Taking?

Section 4 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) directs EPA to reevaluate existing pesticides to ensure that they meet current scientific and regulatory standards. In 2006, EPA issued a RED for malathion under section 4(g)(2)(A) of FIFRA. In response to a notice of availability published in the Federal Register of November 29, 2006 (71 FR 69114) (FRL-8104-2), the Agency received substantive public comments and new data from the technical registrant. The Agency's response to comments is available for viewing in the public docket. The revised malathion RED reflects changes resulting from Agency consideration of these comments and the new data received on provisions of the RED, as well as efforts by the Agency to appropriately mitigate overall risk. The revised RED for malathion concludes EPA's reregistration eligibility decision-making process for this pesticide.

In response to a Data Call-In issued in October 2004, the Agency received a special acute and repeat dose comparative cholinesterase (ChE) assay with malaoxon (the active ChE inhibiting metabolite of malathion) and malathion in March 2008. The study and post-RED comments have enabled the Agency to refine several toxicological assumptions for malathion. If these refined values were to be incorporated into the human health risk assessments for malathion, the estimate of risk from exposure to malathion would likely be reduced. Although the human health risk assessments have not been revised to include the new toxicity assumptions, the refinements from those used in the RED, which were sufficient to demonstrate a level of risk below the Agency's level of concern, confirm that conclusions in the human health risk assessments were adequately conservative to protect human health.

The revised malathion RED includes a revised label table that modifies label language for consumer products, ultra low volume applications, and the use patterns for a number of specific crops. Additional revisions include: Updates on the status of two endangered species assessments that include malathion; clarification of how the Boll Weevil Eradication Program was considered in the Agency's residential risk assessments; descriptions of recent studies examining isomalathion (an impurity present in malathion). A comparison of reassessed U.S. tolerances (listed in 40 CFR 180.111) relative to Canada, Mexico, and Codex maximum residue limits has also been added. Additionally, the Agency has revised the confirmatory data requirements for malathion, removing the requirement for an aerobic aquatic metabolism study with malathion and a comparative Che study with malathion and malaoxon.

After considering public comments submitted after the 2006 RED was issued, for a limited number of crops, the Agency has increased the allowed number of applications per crop cycle from what was proposed for these crops in the 2006 RED. In the 3 years since the RED was issued, several comments raised substantive concerns about whether the proposed use patterns would allow efficacious control of target pests. The Agency investigated these claims and found that in some cases, an adjustment to the allowed number of applications was justified. Although the Agency routinely evaluates the needs of pesticide users during the development of its REDs, new concerns arise during public comment periods, particularly for pesticides available for as wide a variety of applications as malathion. Recent endangered species assessments conducted both by the Agency and the National Marine and Fisheries Service which include malathion, are based on the highest use rates that appear on current, EPA-approved product labels. These labels have not yet been revised to implement use rate reductions specified by the malathion RED. The increases to the allowed number of applications of malathion to certain crops introduced in the revised RED remain, without exception, reduced from those rates which were utilized in recent endangered species assessments.

B. What is the Agency's Authority for Taking this Action?

Section 4(g)(2) of FIFRA, as amended, directs that, after submission of all data concerning a pesticide active ingredient, “the Administrator shall determine whether pesticides containing such active ingredient are eligible for reregistration,” before calling in product-specific data on individual end-use products and either reregistering products or taking other “appropriate regulatory action.”

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Dated: June 18, 2009.

Peter Caulkins,

Acting Director, Special Review and Reregistration Division, Office of Pesticide Programs.

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[FR Doc. E9-14864 Filed 6-23-09; 8:45 am]