By Josh Loeb
High concentrations of toxins assumed to have originated from the use of flea and tick treatments for pets have been found in rivers across England, prompting fresh concern about the impact veterinary ectoparasiticides have on the environment.
As part of a Veterinary Medicines Directorate (VMD)-funded project, a team led by Dave Goulson and Rosemary Perkins from the University of Sussex examined the occurrence of fipronil, fipronil metabolites and the neonicotinoid imidacloprid in 20 English rivers from 2016 to 2018 using water samples collected by the Environment Agency.
There is no record of these chemicals being used in agriculture since 2016 and they are now banned for agricultural use. However, they are still allowed to be used in some horticultural settings and in products for cats and dogs.
Researchers found there was widespread contamination of rivers with these chemicals, with concentrations well above ‘safe’ thresholds.