Seresto Pet Collar Poisoning May Have Caused Nearly 1,700 Pet Deaths, Hundreds of Human Injuries

A popular flea and tick pet collar may have caused hundreds of animal deaths and nearly 1,000 adverse health reactions in humans, according to an investigative report, which calls on federal regulators to take action and remove Seresto pet collars from store shelves to prevent additional injuries and deaths.

In findings published this week by USA Today, investigators indicate Bayer’s Seresto flea and tick collars have caused more than 75,000 adverse health reactions among humans and pets since they were first introduced to the market in 2012.

The flea and tick collars are designed to release small amounts of pesticide onto the skin of cats and dogs for months at a time to kill fleas, ticks and other pests. However, the side effects of Seresto collars may include a serious poisoning risk for pets and humans.

According to federal documents retained through a public records request by the nonprofit organization the Center for Biological Diversity, officials at the Environmental Protection Agency (EPA) know of more than 75,000 incident reports involving problems with Seresto collars, including 1,698 related pet deaths and nearly 1,000 incidents involving harmful human exposures to the pesticides. However, the agency took no actions to address the problem and has not issued any warning, which investigators from USA Today claim is a failure in their regulatory obligations.

In addition to the regulatory oversight, investigators noted numerous complaints filed on, where Seresto is the top-selling collar. The investigation found  complaints from consumers indicating the collars caused pets to develop painful rashes, while some claimed the pesticides caused their pets to suffer neurological issues.

The investigation highlights one report from Rhonda Bomwell, a New Jersey resident who used a Seresto flea and tick collar on her 9-year old papillon service dog, as recommended by the veterinarian. Bomwell reported she purchased the Seresto collar at her local pet store, and within a day of her papillon wearing it, the dog collapsed and began having seizures. The papillon, named Pierre, stopped breathing and died shortly after being rushed to the animal hospital.

Within the thousands of incidents submitted to the EPA, investigators found a series of reports of pesticide exposures which harmed humans as well. One incident involved a 12 year old boy who had to be hospitalized after having seizures and vomiting from exposure to the Seresto collar his dog was wearing.

Another incident involved a 43-year-old man who put Seresto collars on eight of his dogs and slept in the same bed as four of the dogs. Within a week he developed ear drainage and nasal and throat irritation and was told by a doctor that he had a hole in his ear drum. After removing the Seresto collars from his dogs the symptoms went away. He later reapplied the collars and the symptoms returned.

Investigators indicate that under the Federal Insecticide, Fungicide and Rodenticide Act, the EPA is tasked with regulating products that contain pesticides, yet appear to have turned a blind eye to the tens of thousands of human and animal incidents reported over the last seven years.

The Midwest Center for Investigative Reporting, which cosponsored the investigation, said the EPA did not respond to a request about how Seresto compared to other flea and tick collars in terms of incidents. The organization has since filed a Freedom of Information request for the incident database related to Seresto pesticide collars, but says that request has not yet been filled.

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  1. Taylor Reply

    I believe seresto flea collar is causing CKD in my cat. I had blood test to prove it. When on she failed her test months later off collar A’ced her test then on collar again failed BUN. I believe there is a connection between her kidneys and the collar. Bayer is evil, they don’t pay enough money to do thorough testing important tests. they look at a couple results and go okay, money will do the rest.

  2. Betty Reply

    We have been using this collar for years. When this notice came out we removed the collar and Harley was no longer lethargic. Now my sweet boy has hard lumps under his skin that are popping up all over him. I don’t know if it related… yet

  3. Ron Reply

    I believe Seresto caused the deaths of both of my Italian Greyhounds. I bought the collars in March, 2020. My 5 year old was diagnosed with a Spleen tumor in July 2020 and died in September. The vet told me the tumor was extremely rare in that breed, especially a dog that young. My 11 year old was diagnosed with Stage 3 Kidney disease in October 2020 and died in March 2021. Both dogs were healthy otherwise with consistent vet visits and a healthy diet. I still have the containers the collars came in, and the last photos I have of both dogs show them wearing the collars.

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