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EPA Draft Malathion Human Health Assessment Available

For Release: September 15, 2016

Updated November 18, 2016 -- The comment period will be open until December 21, 2016.

Read the Federal Register Notice

EPA is making the draft malathion human health risk assessment available. For this draft risk assessment, EPA considered exposures from all sources, including food, drinking water, and insect sprays.  In addition, EPA considered all populations including infants, children, and women of child-bearing age.

The public comment period for the draft human health risk assessment will open as soon as the Federal Register Notice publishes in the weeks ahead. View the draft assessment. Once the comment period opens, EPA invites the public and stakeholders to comment on the draft human health risk assessment, which can be found at: in the “Supporting Documents” Section of docket EPA-HQ-OPP-2009-0317.

Malathion is an organophosphate insecticide used on a large variety of agricultural (food and feed crops) and non-agricultural sites. Some products are available to consumers for outdoor residential uses, including vegetable gardens and ornamentals. Malathion is used in the United States Department of Agriculture’s Cotton Boll Weevil Eradication Program and Fruit Fly (Medfly) Control Program, and by mosquito control districts around the United States for mosquito-borne disease control. Less than 1% of spraying for mosquitoes is malathion aerial spray.

Given the current importance of mosquito control to minimize transmission of the Zika virus and other mosquito-borne diseases, EPA has provided mosquito control professionals in local governments and mosquito control districts with advice on malathion aerial spraying based on the draft risk assessment results. While EPA would normally not make risk management recommendations based on a draft risk assessment, EPA has provided this information to mosquito control districts in the interim so they can be confident in the safety of malathion aerial spraying applications.  Learn about malathion’s use as a mosquito adulticide.

It is important to note that EPA’s assessments are intentionally conservative in order to be protective of the most sensitive populations who may also experience the highest possible exposure. EPA is currently seeking public comment on this draft risk assessment and will update the assessment as appropriate.