31 Jan
New review of impact of treatments is demanded as some products linked to increased mortality in two bird species.
Campaigners and academics have demanded a fresh review of the environmental impact of parasiticide treatments after new fears were raised about their potential consequences.
Supporters of tighter regulations said research led by the University of Sussex, which linked the products to increased chick mortality in two bird species, “adds another level of urgency” to the issue.
While the BVA called for further studies, the body that represents product manufacturers, insisted environmental considerations were already part of the regulatory process.
But the VMD said it was backing plans for a review of international guidelines for environmental impact assessments.
The study, published in the Science of the Total Environment journal, analysed fur samples from 103 blue and great tit nests for the presence of 20 substances, including those most commonly used for parasiticide treatments.
Two of them, fipronil and imidacloprid, were detected in 100% and 89% of samples, respectively. All of the nests contained at least two chemicals, with a maximum of 11 recorded in some individual samples, while 17 of the 20 substances tested for were detected in all.
The paper also reported a “significant interaction” between total concentrations and both dead offspring in urban areas and unhatched eggs across all samples.
Although the study, which was funded by the charity SongBird Survival, acknowledged the possibility of some products being used illegally in agriculture and called for further research, it argued fipronil concentrations within the range found on dogs four weeks after treatments confirmed they were “the most likely source” of contamination.
Lead author Cannelle Tassin de Montaigu also warned the situation could be even worse, as the analysis was undertaken at the end of the breeding season for safety reasons.
She said: “This raises questions about the environmental impact of veterinary drugs and calls for a comprehensive environmental risk assessment of veterinary treatments.”
SongBird Survival chief executive Sue Morgan said the research showed the need for urgent steps to address the “crisis” among songbird species, while the call for action was also backed by Pesticide Action Network UK, which has previously led demands for tougher regulation.
Policy manager Nick Mole urged the VMD and Defra to make products containing fipronil and imidacloprid available only via prescription, adding: “This latest research adds another level of urgency to the issue.
“It seems absurd that active substances banned from use in agriculture due to their potential to cause harm to the environment are allowed in pet treatments, where, as this and other research shows, they are causing harm to the environment.”
The VMD said it was aware of “emerging evidence” about the effect on birds’ nests but argued further research was needed to draw firm conclusions.
But while it also highlighted its work to develop a new strategy, a spokesperson added: “The VMD follows internationally recognised guidelines for the environmental assessment of companion animal parasiticides.
“In light of new evidence, a review of these guidelines has been proposed, with the VMD’s full support.”
Meanwhile, NOAH said VMD assessments already considered the safety of products “for pets, people and the environment” and parasiticides were “essential” both to protect animals and reduce the spread of zoonotic diseases.
A spokesperson added: “NOAH urges pet owners to always read the packaging and follow the information provided with a pet’s medicine to ensure it is used correctly and we are active in promoting this message through Paws to Protect and our other campaigns.”
BVA president Elizabeth Mullineaux also agreed that parasiticides still had an important role, but said the study had shown the need for further analysis.
She added: “Rather than blanket use, we strongly encourage vets and owners to take a risk-based approach to prescribing or recommending these medicines, reflecting an animal’s exposure to parasites.
“Owners should speak with their vet about their animal’s needs and how to responsibly use and dispose of these medicines to minimise environmental contamination.”