As warmer spring temperatures spread across much of the country, people and pets are spending more time outdoors, and fleas and ticks are becoming active again. Many pet owners rely on flea and tick treatments to keep their animals protected, but new research suggests that some of these medications may have unintended consequences.
One commonly used group of these medications is called isoxazolines, which are a relatively new class of antiparasitic drugs. Introduced in 2013, these medications quickly became popular because they were among the first oral treatments able to control both pests for a month or longer.
But according to a new study led by researchers from VetAgro Sup, a French public research institution, isoxazolines can enter the environment through pet waste. After a dog or cat takes the treatment, the active ingredients move through the animal’s body and are eventually excreted in feces, urine, and even shed hair.
In the study, which was recently published in the journal Environmental Toxicology and Chemistry, the research team found that even after the recommended treatment period had ended, two of the four commonly used active ingredients were still detectable in the animals’ waste.
Researchers warn that these chemical residues could threaten non-target insects, including flies and dung-feeding beetles. These species play an important role in ecosystems by recycling nutrients, improving soil health, and helping control pests.
Pet owners can help reduce the harmful environmental impacts of these medications by disposing of their pet waste in sealed bags, and by working with their veterinarian to choose the most targeted treatments for their pets.
