A NEW British study has revealed that chemicals commonly found in spot-on flea treatments for dogs have been found in concentrations shown to have a negative impact on the environment in water where treated animals have been swimming up to 28 days after application. This data goes against current guidelines that typically suggest not allowing dogs to swim for 2-4 days following application.

Medicines widely used for the prevention or treatment of parasites, such as fleas, ticks and worms, in cats and dogs, are typically applied as a monthly spot-on treatment on the back of the animal’s neck.

Despite being important tools to protect human and animal health from parasites, there are increasing concerns about the negative impact these chemicals have on the environment.

The study found the chemicals in water samples tested during a 28-day period after treatment, despite the guidelines suggesting it was safe for dogs to swim.

In addition to encouraging more research, the study also echoes long-standing calls from the British Veterinary Association for a move to risk-based treatment, based on the individual circumstance of the animal and owner, rather than blanket, monthly treatments, to mitigate the impact and promote more sustainable parasite control.