Petco pest products

VIN News Service photo

The U.S. Environmental Protection Agency regulates about 600 topically administered pet pesticide products, including these displayed at a Petco store. The EPA and the U.S. Food and Drug Administration have proposed that the FDA take over this responsibility.

Oversight of roughly 600 parasite prevention products used on pets would be handed off from one federal regulatory agency to another under a joint proposal by the U.S. Environmental Protection Agency and U.S. Food and Drug Administration.

The EPA, which has authority over flea and tick products applied to the skin or worn externally, indicated in a new report that it lacks the resources of its sister agency, the FDA, to efficiently and most effectively evaluate and monitor pet parasiticides. The report, dated Feb. 17, was developed by both agencies. 

The proposal to shift pet parasiticide oversight to the FDA comes as the EPA is immersed in an internal review of how it responded to tens of thousands of adverse-incident reports associated with Seresto flea and tick collars for dogs and cats.

The collars, which are made by Elanco Animal Health, have been the subject of public scrutiny since USA Today reported in March 2021 that they were implicated in hundreds of pet deaths. Last year, federal lawmakers called for the collars to be taken off the market, based on what they called an unacceptably high number of adverse-incident reports, internal emails from EPA scientists revealing stifled concerns and the decision by Canadian regulators not to allow the sale of the collars in that country. 

At the time of the hearing in June, some veterinarians, including veterinary toxicologists, told the VIN News Service that the evidence thus far didn't present a consistent or coherent picture of heightened risk for a collar that is effective at protecting pets against fleas and ticks.

Discussions about changing the approach to oversight predate the current Seresto review by years, according to a statement provided to VIN News by EPA spokesperson Cathy Milbourn.

"But EPA's ongoing review of Seresto pet-related incident reports has indeed highlighted that, as compared to FDA, EPA has fewer resources (e.g., staff, expertise, infrastructure, and funding) to evaluate animal safety and conduct ongoing monitoring of marketed products," the statement said. "This challenge has highlighted the importance of developing an enduring solution that improves oversight of the safety of pet collars."

The proposal would upend a 50-year-old approach to regulation. Executing the shift requires changes in law. As it stands now, pet parasite control products overseen by the EPA are registered as pesticides. The EPA and FDA agree that they would be more appropriately regulated as animal drugs, which is the FDA's domain.

The agencies are co-hosting a virtual public meeting on March 22 on "modernizing their approach to oversight on certain products." Those who wish to attend must register by 11:59 pm Eastern time tomorrow, March 15. The proposal is also open for public comment through April 24. 

Also under consideration is how the EPA and FDA can improve the regulatory process for biotechnology as a pest control tool — such as the use of genetically engineered animals like mosquitoes — something that wasn’t on the radar when the existing framework was established.

Revising product oversight

In the 1970s, oversight for products topically administered to animals to treat fleas and ticks was divvied between the newly established EPA and the FDA based on whether the chemicals were absorbed into the bloodstream, according to the white paper on the proposed reshuffle. The EPA became responsible for those products that were believed to remain on the skin; the FDA got those that were systemic. 

The agencies say in the white paper that they now understand that many of these topically administered products — such as spot-on treatments and collars — are, in fact, absorbed in the bloodstream.

"This improved scientific understanding combined with the development of novel ingredients, long-lasting products, and other technological advances, has highlighted additional potential animal safety concerns (supported by new toxicological data and reported adverse incidents)," the paper says, adding later: "Both agencies agree that FDA's animal safety evaluation process is best equipped to evaluate and monitor products topically administered to animals."

The report cites the fact that the EPA has fewer resources for this type of work compared with the FDA. The proposal says the cost of expanding oversight at the FDA will be significant but less than bolstering efforts at the EPA because so many resources are already in place at the FDA's Center for Veterinary Medicine.

Meanwhile, what about Seresto?

To pet owners and veterinarians seeking conclusions about Seresto incident reports, the proposal to shift oversight may be small comfort because the change, if it happens, is likely to take some time.

Seresto cat and dog collars are designed to slowly release small amounts of the active ingredients flumethrin and imidacloprid for months at a time. The collars were brought to market in 2012 by Bayer Animal Health, which was acquired by Elanco Animal Health in 2020. More than 33 million collars have been sold, Elanco President and CEO Jeffrey Simmons said during last year's congressional hearing.

"No product is without risk," Simmons told the committee in a prepared statement. "What matters is whether those risks are reasonable, in light of the benefits. Numerous studies and the incident report data for Seresto demonstrate the product does not pose an unreasonable risk."

Several veterinary toxicologists have told VIN News that whether the collar is the true cause of reported harms is unclear. Adverse-event reports are unverified and anecdotal, they said, and drawing conclusions from that raw data is imprudent.

The EPA told VIN News last summer that it expected to finish a review of incident data in the fall to determine whether the collars "can still be used safely according to the instructions on the label or if additional safety measures or cancellations are needed for these products."

A representative of the EPA reportedly told USA Today last week that the agency's re-evaluation of incident reports should be complete in a few months.