06/07/2021
VETERINARY FLEA PRODUCTS POTENTIALLY CAUSING WIDESPREAD CONTAMINATION OF ENGLISH RIVERS
A new study, due to be published in February 2021, has highlighted widespread contamination of English rivers with two toxic pesticides commonly used in flea and tick pet treatments - fipronil and imidacloprid. The concentrations of these products were often found to be at levels well above safety thresholds and likely to impact aquatic ecosystems. The use of both these chemicals in agriculture had been limited because of their toxic effects on insects, birds, fish, mammals and other creatures.
Fipronil and imidacloprid are commonly used, either alone or in combination with other parasiticides, in pet flea and tick control products including spot-on solutions, topical sprays and collars. Millions of dogs and cats are routinely treated in the UK multiple times per year.
The researchers examined the occurrence of fipronil, fipronil metabolites and imidacloprid in 20 English rivers from 2016 to 2018. The sites immediately downstream of wastewater treatment works had the highest levels of fipronil and imidacloprid, suggesting that significant quantities of the pesticides from veterinary flea products may go from household water to waste treatment plants and then enter rivers. It appears that after pets receive treatment, the chemicals can wash off into bathwater, or from washing hands, pet bedding or other surfaces that have come into contact with treated pets. They then leak from wastewater treatment plants into nearby waters, killing wildlife. Imidacloprid and other neonicotinoids are known to be associated with plummeting bee numbers around the world, causing brain damage that affects their ability to forage for nectar and pollen.
The research findings suggest the need for a re-evaluation of the environmental risks associated with the use of companion animal parasiticide products, and the environmental impact assessments that these products undergo prior to regulatory approval. A more judicious and risk-based approach, giving serious consideration to both the risks posed by parasites and the environmental risks associated with the use of these products, may be necessary if environmental harm is to be avoided. The introduction of stricter prescription-only regulations, and updated guidance for veterinary surgeons and sellers of flea and tick treatments on the provision of these products for pet owners, in which environmental risks are made explicit, might also be considered.
You can read the abstract here: https://www.sciencedirect.com/science/article/abs/pii/S0048969720370911