Veterinary Products in Waterways

Debate between Rachel Gilmour and Jayne Kirkham

Tuesday 25th March 2025 Commons Chamber

[Rachel Gilmour (Tiverton and Minehead) (LD)]

I am delighted to secure my first Adjournment debate, and for it to be about veterinary products in waterways, specifically neonicotinoids such as fipronil and imidacloprid. From now on, for your sake and mine, Madam Deputy Speaker, I shall be referring to these neonicotinoids as neonics.

I have been extremely keen to secure a debate on this matter for some time now, having had it raised with me before the general election by a constituent, Ueli Zellweger, who is a vet. It is high time that we gave this topic the scrutiny that it so desperately needs.

We are a nation of pet lovers. It is estimated that there are around 25 million cats and dogs in the UK. I speak as a doting dog and cat owner myself and I know that our furry friends are an integral part of millions of British families. And so when fleas and ticks come biting, bringing discomfort and annoyance to our beloved pets, we of course want to act swiftly and efficiently to alleviate their suffering.

Flea treatment products containing fipronil and imidacloprid are seen as a highly convenient and effective way of dealing with the problems caused by fleas and ticks. In the UK, Imperial College London claims that fipronil is an ingredient in 396 different pet anti-flea and tick treatments, with imidacloprid authorised in some 138 veterinary products. However, this convenience comes at a cost to our waterways and associated ecosystems. Popular though these products are, safe they are not. These two ingredients are extremely toxic. They are very powerful killers indeed and the picture is not pretty. In fact, so powerful are these chemicals that just one drop of fipronil has the potency to wipe out 30,000 bees as well as causing serious neurological damage and hampering the mobility of thousands upon thousands more.

As well as this, according to extensive research conducted by Imperial College London, one monthly flea treatment for a large dog contains enough imidacloprid to kill a staggering 25 million bees. The decline in pollinator populations, which in part can be attributed to the use of imidacloprid, threatens agricultural productivity and has very serious long-term implications for our national food security. This is not simply a mere triviality to be neglected.

Authorities have recognised the toxicity levels and the hideous harm that these chemicals can cause on the natural world. Since 2017, fipronil has been banned in agricultural use, and imidacloprid has been banned since 2018. But given the unregulated nature of these chemicals in relation to flea products, we are allowing these products into our environment through the back door, and our aquatic and nearby ecosystems are paying the price.

There is not just one route for these neonics to enter our British waterways. It is important to be aware of all the various pathways towards this pollution. The most obvious, and most direct, is simply the contact of pets with water bodies themselves. If a dog goes swimming in a river after receiving their course of treatment, the product is then introduced into the waterways, allowing it to enter our rivers, lakes and streams and go wherever the water takes it, wreaking havoc as it travels. Dissemination can also occur because of rainwater run-off, with residual product washing off from treated animals into drainage systems and ending up in our waterways. Equally, the washing of pet bedding and even pet owners’ hands are thought to be common ways in which these dangerous products enter our waterways.

There are some less direct pathways that still pose a problem—and at this point I must apologise to those currently eating their supper. These products are generally harmless to our dogs and cats, but they can be absorbed by our four-legged friends. Once absorbed, the products can be excreted, and even when responsible owners clean up after their pets—something that is not universal, unfortunately—the traces of fipronil and imidacloprid left behind can still prove incredibly damaging once washed into our waterways.

Studies have revealed that imidacloprid is one of the most frequently detected pesticides in dogs’ urine, but the level is still comparatively low, with the National Office of Animal Health finding that only around 11% of topically applied fipronil is systematically absorbed. The shedding of treated hair or skin can also lead to a pathway being created.

Once these products are in our waterways, not only are they utterly deadly for the thousands of native aquatic organisms in the UK, but they are highly toxic to sea and freshwater fish. Even at low concentrations, fipronil can be disruptive to aquatic life cycles. River sample data gathered by the UK Environment Agency over the course of a two-year period between 2016 and 2018 from 20 different waterways in England discovered fipronil residue in 98% of freshwater samples and traces of imidacloprid in 66% of all samples.

Beyond the effect on our waterways, other studies have found fipronil to be incredibly toxic to birds. It brings me no joy to report that this is not just an aquatic problem. Indeed, through a process of collecting 103 different bird nests, researchers found that every single one without exception contained fipronil, and an overwhelming majority had significant remnants of imidacloprid.

The truth is that the decline in aquatic insects that emanates from the flowing of these products in our waterways affects fish populations, who rely on these insects as a primary food source. This in turn impacts bird species that prey on fish, producing a dangerous snowball effect that reverberates throughout the ecosystem. This deterioration of biodiversity greatly diminishes the overall resilience of our ecosystems, exposing a vulnerability to factors of climate change and invasive species.

One of the most troubling aspects of the likes of fipronil and imidacloprid is their persistence in the environment. The chemicals disintegrate slowly and can remain in soils and waterways for extensive periods of time. In the case of imidacloprid, scientists say that the residual effect lasts in soil for months, sometimes even years, and the breakdown product of these chemicals is understood to be even more toxic than the parent compound.

[Jayne Kirkham (Truro and Falmouth) (Lab/Co-op)]

Does the hon. Member agree that some pet owners may not be aware of how bad this issue is, and so packaging, usage guidance and point-of-sale advice for pet treatments should give some warning of the danger that the product could affect aquatic life if it ever entered watercourses?