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EPA Protects Aquatic Ecosystems by Finalizing Irgarol Antifoulant Paint Cancellation

For Release: April 28, 2021

Today, the U.S Environmental Protection Agency (EPA) is releasing the interim decision for irgarol, which finalizes the cancelation of its use as an active ingredient in antifoulant paint in order to help preserve America’s diverse aquatic ecosystems. After completing an ecological risk assessment, EPA determined that irgarol, which is used in antifoulant paint and as a materials preservative in algicidal paints, is toxic to both freshwater and marine plants, including causing the bleaching of coral.

The interim decision will also protect Americans’ health by requiring irgarol powders—which are used to preserve sealants, vinyl roofing, cements, and other building materials—to be sold in packaging that reduces users’ exposure.

EPA’s action is in line with the International Maritime Organization’s Marine Environment Protection Committee session 75 proposal to ban the antifoulant paint use associated with irgarol. EPA has also worked with manufacturers to identify a number of alternatives to irgarol.

The Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) requires EPA to periodically review pesticides to ensure that risk assessments reflect the best available science. The interim decision is part of a multi-step process to identify risks as well as actions that can mitigate risks.

EPA uses interim decisions to finalize enforceable mitigation measures while conducting other longer-term assessments.  EPA will make a final registration review decision after completing an endangered species determination.

Upon publication of the Federal Register notice, the interim decision will be available in docket ID number EPA-HQ-OPP-2010-0003 at


Irgarol is an antimicrobial pesticide most commonly used as an active ingredient in antifoulant paints for boat hulls. Under EPA’s interim decision, revised labels must be submitted within 60 days after the interim decision is published, and the last use of existing stocks to occur before January 1, 2023. For products that are only registered with EPA for antifoulant paint uses, registrants must submit a voluntary cancellation request by January 1, 2023. EPA will actively work with registrants to make label amendments or product cancellations.