Pet Pesticide Pollution in UK Rivers Mostly Comes from Wastewater Sewage Treatment After Handwashing Pets [Study]

Pet pesticide pollution has affected some rivers in the United Kingdom for many years, affecting freshwater habitats and animals. Now, a new study suggests that the major source of this environmental issue is chemicals used against fleas and ticks during pet handwashing. The residue used in this procedure then ends up in UK rivers through wastewater from sewage treatment.

The study is led by researchers from the University of Sussex and Imperial College London. They found that pet pesticides like fipronil and imidacloprid are highly toxic and are no longer approved by authorities to be used in outdoor agriculture.

However, these pesticides are still widely used in pet flea treatments. Authorities warn the pesticide pollution in UK rivers could harm aquatic life.

Pest pesticides, as in the case of the UK, are part of the multiple causes of river pollution, including untreated sewage, agriculture fertilizer, and industrial pollution. The findings of the study shed light on the topic of river pollution caused by pest pesticides, it can also occur in different river systems in the world.

In this context, the pollution is expected to occur more in urban areas.

Pet Pesticide Pollution

The UK authors of the study published their findings on the impact of pet pesticide pollution and pet handwashing in UK rivers in the journal Science of the Total Environment. The new research paper explores the dangers posed by spot-on parasiticides like fipronil and imidacloprid to dogs. It implies that the outlet of these toxic chemicals is down the drain through handwashing.

The research team concludes that wastewater is a "major entry pathway" for fipronil and imidacloprid to UK surface water, accounting to an estimated 20% to 40% of wastewater pollution. This result was determined possible by quantifying pesticide emissions from bathing, bed, and handwash emissions from dog pest treatments, according to the 2024 study.

Furthermore, the team collected samples from 98 pet dogs that were treated using the said 'highly toxic pet pesticides.' They also examined the contribution of various factors to UK river pollution, including owner handwashing, dog bathing, and dog bedding washing, as well as household sewage and subsequent wastewater pollution.

Pet Handwashing

Pet handwashing or washing one's hands following contact with pets is the most recommended practice by health authorities to maintain hygiene and prevent diseases, including those from parasites and bacteria. Besides pet flea treatments, washing your hands is necessary after touching or feeding your pets, according to the Centers for Disease Control and Prevention (CDC).

The CDC adds that despite contact with animals has many beneficial effects for humans, our beloved pets can carry harmful germs with the potential to make people sick. This scenario can happen in spite of the fact that the animal looks healthy and clean on the outside. The US health body also recommends using soap and water in areas where the animals live or roam.