As of March 2, 2021, at least 1,700 pet deaths (dogs & cats) have been attributed to a popular flea collar under the Seresto brand (developed by Bayer and now sold by Elanco). The variety of collars used for all sizes of dogs and cats works by releasing small amounts of two pesticides (imidacloprid and flumethrinphos) onto the animal for months at a time. The pesticides were developed to kill fleas, ticks and other pests while not harming the cats, dogs and human handlers.
However, thousands of reports of harmed pets have been obtained through a public records request from the Center for Biological Diversity, a nonprofit organization that watchdogs the Environmental Protection Agency (EPA) as part of its work to protect endangered species.
Since Seresto flea and tick collars were introduced in 2012, the EPA has received incident reports of at least 1,698 related pet deaths. Further, through June 2020, the agency has received more than 75,000 incident reports related to the collars, including nearly 1,000 involving human harm.
Even with these numerous and ongoing reports, the EPA has not issued a warning or recall for the flea collars. And even though Amazon.com has also received direct reports and complaints, they have continued to offer Seresto collars for sale on their site.
As a result, Seresto continues to be one of the most popular flea and tick collars in the country even after having been linked to hundreds of pet deaths, tens of thousands of injured animals and hundreds of harmed humans, according to the EPA’s own documents.
Yet the EPA has not been compelled to inform the public of these ongoing risks.
And 2013 and 2018, 907 incidents were reported with humans, according to a September 2019 EPA assessment of human health risk.
The assessment determined that there were 19 severe incidents, and of those, eight people had dermal symptoms (i.e. rash or hives) and seven had neurological symptoms, including numbness and headaches.
Incidents listed by the EPA included:
- A 12-year-old boy who slept in a bed with a dog wearing a collar when the boy began having seizures and vomiting. He had to be hospitalized.
- A 67-year-old woman who slept in a bed with a dog wearing a collar reported having heart arrhythmia and fatigue.
- A 43-year-old man put collars on eight dogs and slept in the same bed as four of them. A week later, he developed ear drainage, nasal and throat irritation, and was told by a doctor that he had developed a hole in his ear drum. He removed the dog collars and the symptoms vanished. When he reapplied the collars and the symptoms returned.
An October 2016 EPA bulletin responded to citizen concerns about children being exposed to Seresto, saying it had found exposure to the collars to be negligible.
“As stated in the precautions on the label, do not allow children to play with the collars. In addition, try to keep the pet away from young children for a day after putting on the collar to minimize exposure,” the bulletin said.