Chemicals that are banned for use as pesticides but still used in flea treatments are harming wildlife, according to a new study. The assessment, published on Thursday, reveals that toxic substances in pet flea treatments are devastating aquatic life, birds, and pollinators in rivers, parks, and conservation areas across the UK.
Study Highlights Environmental and Health Risks
The study by ecologist Matt Shardlow from Wildlife and Countryside Link found that flea treatment chemicals fipronil and imidacloprid are causing potentially irreversible damage. These chemicals have also been linked to lower cognitive and adaptive scores in children with autism. The Environment Agency ranks one of these chemicals as posing the highest risk to human health in English waters.
“The more you look at this, the worse it gets,” said Shardlow. “The level of new alarming information showing the scale of damage that is being done by these chemicals is stark.”
Widespread Contamination
Last month, the Guardian reported on calls for restrictions after research found songbird feathers widely contaminated with chemicals that can damage their brains and kill unborn chicks. A previous study showed chicks were being killed by high levels of pesticides in pet fur used by parents to line nests.
The analysis found irreparable damage may have already occurred to rivers, sites of special scientific interest, and National Parks. In the Broads, Norfolk, all main rivers entering the park are heavily contaminated with flea treatment toxins, and Natural England is concerned about a 90% decline in dragonfly numbers.
Impact on Aquatic and Bird Life
Average levels of fipronil and imidacloprid in English rivers are high enough to reduce aquatic life. In a fifth of cases, levels were sufficient to cause a 30% reduction in associated bird populations. “We are seeing not just impacts in rivers but in public parks where dandelions were so heavily polluted that it is likely to harm caterpillars and pollinators,” said Shardlow.
Main Source of Contamination
Flea and tick treatments, commonly used on dogs and cats, are the main route for these chemicals entering the environment. They enter the sewage system when treated animals or contaminated clothing are washed, and can also get into the environment when dogs swim, pets rub against vegetation, or shed fur outdoors.
Government Response
The government announced an eight-week consultation on banning over-the-counter sales of these treatments for cats and dogs. However, Shardlow said this does not go far enough, as products would still be widely available in pharmacies, supermarkets, vets, and online. He called for an urgent environmental risk assessment and urged the Veterinary Medicines Directorate to review, suspend, and ban flea treatments containing fipronil and imidacloprid.
A spokesperson for the Department for Environment, Food and Rural Affairs said the government is committed to restoring nature and cleaning up rivers while upholding animal welfare standards. The Veterinary Medicine Directorate acknowledged the benefits of these chemicals but recognized their environmental impact and encouraged responses to the consultation.
