Flea Treatments in Dogs Found to Contaminate Water with Pesticides for Weeks

Speedy Summary

• Dogs treated with spot-on flea products release harmful pesticides (e.g., fipronil and imidacloprid) into water when they swim, affecting aquatic wildlife and birds.
• Research shows that even 28 days after treatment, pesticide levels released by a dog can exceed safe environmental limits for water bodies.
• Regulators initially assumed spot treatments had minimal environmental impact; guidelines recommending dogs avoid water for 48 hours lacked experimental evidence.
• Researchers at the University of Sussex found unexpectedly high levels of pesticides in UK rivers, prompting further inquiry using controlled tests on treated dogs submerged in tubs of water.
• Current guidelines don’t adequately consider such risks. Dog owners are advised to use thes treatments only sparingly and keep their pets out of water for a month post-treatment.
• Oral alternatives exist but may also pose risks to soils due to chemical excretion. Their exact environmental impacts remain unclear.

Image Caption: Dogs treated for fleas release insect-killing chemicals into water when they swim.
Photo Credit: Natalya Maisheva/Shutterstock