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EPA says no to ban on flea collars

Agency requires warning label on Seresto collars linked to pet deaths

by Britt E. Erickson
July 20, 2023 | A version of this story appeared in Volume 101, Issue 24


The US Environmental Protection Agency has denied a legal petition from the Center for Biological Diversity, an environmental group, to ban flea and tick collars linked to thousands of pet deaths and over 100,000 pet injuries. At issue are collars that contain two active insecticide ingredients—the neonicotinoid imidacloprid and the pyrethroid flumethrin. Made by Elanco, the collars are marketed under the brand Seresto.

A small dog wearing a plastic flea and tick collar.
Credit: Shutterstock
The US Environmental Protection Agency will soon require warning labels on Seresto flea and tick collars for pets.

The EPA says the collars can remain on the market, but within 12 months they must include warning labels that describe common adverse effects and include instructions for reporting harmful incidents.

The EPA could not determine a cause for many of the deaths. Those related to the collars were associated with strangulation, often because of a faulty release mechanism, the agency says. But nonlethal incidents, such as neurological effects, have been reported; in some cases, removal of the collar alleviated those symptoms. Because of those findings, the EPA is requiring warning labels and more robust data collection related to incidents, including information on pets’ preexisting conditions.

“We’re disappointed the EPA didn’t cancel Seresto collars, but it’s heartening that they’re alerting pet owners to the troubling risks linked to the product,” Nathan Donley, environmental health science director at the Center for Biological Diversity, says in a statement. “These actions wouldn’t be necessary if due diligence was done seven years ago when concerns about this product were first brought to light, but better late than never.”

The EPA has shortened the approval period for Seresto collars to 5 years from 15 and says it will continue to monitor incident reports during that period.

Earlier this year, the EPA proposed transferring oversight of flea and tick products to the Food and Drug Administration. The FDA currently has jurisdiction over such products if the chemical is absorbed into the blood; if the chemical remains on the skin, the EPA has oversight. That approach isn’t working, because the agencies now realize that many topical products regulated by the EPA are also absorbed into the blood.



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