Flea in the ointment
THE toxic insecticides we use on our pets to treat fleas are polluting our rivers and poisoning water insects, which fish and birds depend on for food. The PDSA estimates that some 80% of the UK’S 21 million dogs and cats are regularly treated for fleas, usually monthly, whether the animal needs it or not, and researchers would like vets to be discouraged from recommending this and regulation enforced.
The ingredient fipronil is the main culprit, found in 99% of samples gathered by the Environment Agency from 20 rivers—from the Test in Hampshire to the Eden in Cumbria—and imidacloprid was found in 67% of samples, with an average concentration up to 38 times higher than chronic toxicity limits. Both have been banned from use on farms for a few years, but are still commonly used to treat fleas and, as the highest levels were found downstream from water-treatment plants, scientists believe people washing their pets in urban areas are the main source; dogs swimming in rivers contribute, too.
Fipronil actually ‘degrades to compounds that are more toxic to most insects than fipronil itself,’ says Rosemary Perkins of the University of Sussex, who led the study. ‘Our results are extremely concerning.’
Prof Dave Goulson explains that one flea treatment of a medium-sized dog with imidacloprid contains enough pesticide to kill 60 million bees. ‘We would expect them to be having significant impacts on insect life in rivers… There isn’t a regulatory process for this particular risk and clearly there needs to be.’