Handwashing is the main cause of pet pesticide contamination in UK rivers, study finds

A new study reveals that hand washing for several weeks after spotting fleas and ticks is the biggest cause of pet pesticide contamination in rivers.

The paper will be published in a magazine Total environmental science.

Study authors from the University of Sussex and Imperial College London are calling for a review of regulatory frameworks and prescribing practices to tackle toxic pet pesticides entering rivers.

Although fipronil and imidacloprid are highly toxic insecticides and are not currently approved for use in outdoor agriculture, they are still widely used to control fleas on pets and are usually applied to the back of your pet's neck. (also known as spot-on).

Researchers found that wastewater from sewage treatment plants is a major source of fipronil and imidacloprid contamination in rivers. They concluded that pesticides used in household pet flea treatments are being flushed into household drains at concentrations that exceed safe standards for wildlife.

significant source of pollution

Researchers collected samples from 98 dogs treated spot-on with fipronil or imidacloprid to assess the effects of owner handwashing, dog bathing, and dog bedding washing on household sewage and subsequent wastewater contamination. did. The study found that pesticide washout occurs in all three of her pathways.

Owner handwashing was the largest source of fipronil or imidacloprid detected in all tests on pet owners for at least 28 days after direct application to the pet. Although current guidelines recommend that owners not touch their pets for 24 hours after administering the product, this study shows that contamination continues to occur throughout the product's period of action.

First author Dr. Rosemary Perkins. The University of Sussex student and veterinarian said: “This study confirms that fipronil and imidacloprid, which are used in flea control agents, are important surface water pollutants.'' “We have dogs and cats and we urgently need to rethink how we contaminate them.” These products are regulated and used. ”

Co-author Professor Guy Woodward, from Imperial University's School of Life Sciences, said: “Despite these chemicals having been banned for outdoor agricultural use for several years, they continue to affect aquatic life in UK freshwater. “Potentially harmful levels of chemicals have been found.” This shows how a largely overlooked but potentially significant source of contamination, flea and tick repellents from household pets, can be contaminating our waterways. Masu. ”

Review of practice

The study builds on a previous study carried out by researchers in Sussex, which found fipronil was detected in 98% of freshwater samples and imidacloprid in 66%. It is also based on a paper by Imperial researchers showing that these chemicals reach urban rivers in concentrations that: Known to be harmful to aquatic life.

Researchers are now calling for a review of regulations and prescribing practices, as current pet flea products do not take into account the extent of river pollution from drain flushing before regulatory approval. This study demonstrated that even when product instructions are followed, significant emissions to the aquatic environment still occur.

The British Veterinary Association recently recommended that veterinarians should avoid comprehensive year-round parasite treatment policies and instead empower individual vets to have informed discussions with their clients. A policy statement was released.

Professor Dave Golson from the University of Sussex, who oversaw the study, said: “These two chemicals are very powerful neurotoxic insecticides and dog owners can get these chemicals into their hands through continued contact with their pets. “It's very worrying that it's being deposited on a daily basis, pet owners.” They would also be outraged if they found out that they were accidentally polluting our rivers using these products. ”