The majority of dogs and cats routinely receive flea and worm treatments containing toxic chemicals – the ‘active ingredients’. Many worm and flea treatments now come together in a single treatment either as a (easy to administer and ever growing in popularity) ‘spot-on’ or as orally administered treatments. Spot-on treatments are finding their way into watercourses, polluting rivers and poisoning aquatic life and orally administered treatments are killing soil organisms when they pass into the environment along with the faeces.
Until I started to research this article I thought that residue of flea and worm treatments from companion animals would literally be a drop in the ocean when compared with parasite treatments used in agriculture. Unfortunately, this is not what I have found and the negative environmental impact of companion animal parasite treatments is more significant than I’d imagined. Parasite treatments for livestock are regulated and according to the ‘agriculture and horticulture development board’, there is detailed guidance for efficient and targeted parasite treatments meaning that residues are kept to a minimum. It has to be said that these stringent safeguards were brought in to limit resistance to the chemicals by the parasites rather than to protect the environment but we have to take our wins where we find them! As part of the licensing process, manufacturers are required to provide detailed information on the environmental impacts of veterinary medicines for use on livestock. Companion animal treatments are exempt from this level of scrutiny, ostensibly because they are used as individual treatments and usually in much smaller quantities. However, because in small animal medicine parasiticides are used prophylactically for prevention as well as treatment and because they are being widely used on a growing population, the quantities are very significant. In contrast with livestock treatments, companion animal parasite treatments are prophylactic and broad spectrum, not targeted.
There 10 million dogs and 11 and half million cats in the UK and that’s a hell of a lot of worm and flea treatments, some of which are ending up in the biosphere, causing harm.
I checked the ‘active ingredients’ in the ‘advocate’ spot-on I had in the cupboard. Advocate cat and dog use the same active ingredients, imidacloprid and moxidectin. It turns out that imidacloprid is a neonicotinoid and in case you don’t know, neonicotinoids are responsible for the collapse of bee populations amongst other ecocides. I had thought neonicotinoids to be totally banned in the EU (and still at the moment the UK), but it turns out that they are ‘restricted’ rather than banned. In this case, ‘restricted’ means they are completely banned in farming (flowering crops in 2013 and all outdoor crops in 2018) and they are now only permitted for inside use – or on companion animals!
Spot on treatments are designed to sit within the lipid layer of the skin – essentially within the fat. The Advocate data sheet explains that after ‘spotting-on’, imidacloprid is rapidly distributed over the animal’s skin and from here, it gets into the plasma.
I checked the ‘active ingredients’ in the ‘advocate’ spot-on I had in the cupboard. Advocate cat and dog use the same active ingredients, imidacloprid and moxidectin. It turns out that imidacloprid is a neonicotinoid and in case you don’t know, neonicotinoids are responsible for the collapse of bee populations amongst other ecocides. I had thought neonicotinoids to be totally banned in the EU (and still at the moment the UK), but it turns out that they are ‘restricted’ rather than banned. In this case, ‘restricted’ means they are completely banned in farming (flowering crops in 2013 and all outdoor crops in 2018) and they are now only permitted for inside use – or on companion animals! Spot on treatments are designed to sit within the lipid layer of the skin – essentially within the fat. The Advocate data sheet explains that after ‘spotting-on’, imidacloprid is rapidly distributed over the animal’s skin and from here, it gets into the plasma. Within one day of application, imidacloprid can be found on the body surface throughout the treatment interval. (All licensed medications have datasheets. For UK medications, the datasheets should be accessible using the NOAH compendium, https://www.noahcompendium.co.uk/home. Unfortunately you have to access them here. Surely they should be included inside the medication packaging too?). Moxidectin is also absorbed through the skin, reaching maximum plasma concentrations approximately 1 to 2 days after treatment in cats and approximately 4 to 9 days after treatment in dogs. Following absorption from the skin, moxidectin is distributed systemically throughout the body tissues, but because it’s fat soluble, its concentrated mainly in the fat. It is slowly eliminated from the plasma as manifested by detectable moxidectin concentrations in plasma throughout the treatment interval of one month. Presumably from here it will enter the environment through urine and faeces.
Within one day of application, imidocloprid can be found on the body surface throughout the treatment interval. Moxidectin is also absorbed through the skin, reaching maximum plasma concentrations approximately 1 to 2 days after treatment in cats and approximately 4 to 9 days after treatment in dogs. Following absorption from the skin, moxidectin is distributed systemically throughout the body tissues, but because it’s fat soluble, its concentrated mainly in the fat. It is slowly eliminated from the plasma as manifested by detectable moxidectin concentrations in plasma throughout the treatment interval of one month. Presumably from here it will enter the environment through urine and faeces.
Meanwhile, Jade Urquhart-Gilmore of vet sustain tells me it is important to not wash pets or let them go out in the rain or in water for approximately a week after treating with a spot-on to avoid the worst contamination of water courses. Unfortunately, she believes there to be little research on residue from spot-on or orally administered parasiticide treatment in faeces, making it difficult to know how long to bin faeces rather than compost it. As an aside, because of the potential for not just parasitcide residues in pet faeces but also parasites themselves pet keepers should always pick up, even if on agricultural land or in the middle of nowhere see ‘environmentally friendly disposal of pet waste’ article. Clearing up after cats that go outside and clearing up urine are more difficult considerations.
Whilst my research started with advocate, after discovering the full horror of imidacloprid, I realised that whilst there are an alarming array of active ingredients it might be best to focus on the worst offenders in terms of damage to the biosphere as the scope of this article is obviously limited. Further research rapidly indicated that along with imidacloprid, fipronil is probably the other most toxic chemical currently used in companion animal parasiticides in the UK. They are both particularly damaging to water courses. Both fipronil and imidacloprid are widely used in spot-ons which means that, in turn, the article is focused on the spot-ons rather than orally administered parasiticides. In managing the excesses of the worst offenders it is perfectly possible to manage the worst excesses of the other active ingredients, both the spot-on and orally administered types (and hopefully cocktails of them all too). There has been growing public awareness around fipronil over the last year or so, I was circulated a petition in the summer of 2021 by a friend. Unfortunately, despite my recirculating it, it only got 2,817 signatures, falling way short of the 1000 required for a parliamentary question.
A recent study cited in the bva-bsava-and-bvzs-policy-position (37), found fipronil and imidacloprid at levels exceeding chronic toxicity in English rivers. The study postulated that these chemicals were likely to have come from household drains because of people washing pets they have recently treated with spot-on.
I think we need that parliamentary question asked more than ever!
- one spot on treatment for a medium sized dog contains enough pesticide to kill 60 million bees! (BVA report)
- Total sales data from the Veterinary Medicines Directorate (VMD) shows that 27,471 kg of fipronil and 33,036 kg of imidacloprid have been sold as flea treatments since the products were first authorised as veterinary medicines in 1994 and 1997, respectively 54,55.
- imidacloprid is 7000x more toxic than DDT (BVA and webinar vet).
Companion animal parasiticides are broad spectrum:
- Advocate cat ‘protects’ against fleas, hookworm, round worm, heart worms, otodectes, eucoleous, notoedres, aelurostrongylus, and thelazia (and everything else in soil and water).
- Advocate dog ‘protects’ against fleas, hookworm, whipworm, round worm, heart worms, angiostrongylus, creneosoma, otodectes, thelazia, sarcoptes, demodex, louse, skinworms, microfilaria, spirocerca and eucoleous
I’ve no idea what half of these are and whether we and our pets need ‘protection’ or not, they are so ‘broad spectrum’ that their ‘friendly fire’ kills pretty much anything without a back bone!
At the same time, we need to keep our pets parasite free – flea infestations (and I speak from personal experience) are not much fun and worm infestations are not very pleasant either. Worm infections can cause health problems in people too (and are spread by fleas…).
Although I have always used these nasties, it’s always seemed sensible to me to only use them as and when the need has arisen. We have used spot-ons for fleas only when we have seen signs of fleas and wormers every 3-6 months. I can’t say that this is because I’d considered their impact on the environment though, I don’t think anyones been thinking about that – until now. Writing this article has made me reappraise the way we do things – that’s for sure.
If we are going to use these chemicals then we need to use them sparingly and in a targeted way.
However, many vets and corporate veterinary practices promote monthly pet care clubs whereby you buy in to treating your pets for fleas and worms every month, whether or not they are infected. Treatments are meant to be tailored to each individual and their risk, for example, indoors vs outdoor cat – but are they?
Parasite treatments advertising seems to rely on generating fear to sell them. The posters for parasite control up in vet waiting rooms are frankly frightening. When still very young, my daughter was frightened that our pets would get lung worm after reading all about it in the vets. I would rather take an educated approach rather than scare people including children.
Subscribers get discount on the products, however, discount on something you don’t need isn’t really discount at all. The larger proportion of veterinary practices are now corporates, making the priority shareholders dividends above human or animal welfare and the environment. Non corporate vet practices find themselves having to compete. Many vets I speak to don’t agree with the monthly pet health clubs. Dr Jane Gray, Head Vet, SPCA, HK described them as ‘a bit of overkill—we normally recommend every 3-4 months to twice a year’
Monthly pet clubs are bad news for life, particularly aquatic life
However, they have been widely taken up by the public, one of my questions in my behaviour questionnaire asks for frequency of parasite treatments and many answer monthly.
The situation is code red urgent but, on the bright side, with decisive swift action it could be immediately drastically improved and ultimately made better.
I’ve been comforted by how seriously the veterinary bodies are taking this issue. The problem has been widely disseminated in the veterinary press since the publication of the BVA, BSAVA and BVZS September 2021 policy position on responsible use of parasiticides for cats and dogs.
What Government can do:
It would also make sense to me to ban at least the very most damaging ‘active ingredients’. However, this would require regulation and we have a Government who is deregulating left right and centre so we can’t rely on that.
What vets can do:
It makes sense in every way that if we are going to use these products we must use them efficiently as much of the damage these chemicals do can be controlled through correct usage.
Current advice from bva, bsava on using treatments includes:
• ensuring clients use the correct dosage, can apply a product correctly, and avoid hand contamination and spillage.
BVA, BSAVA and BVZS now recognise that they need to do better and have demonstrated how with their recent, hard hitting ‘policy position on responsible use of parasiticides for cats and dogs’ published in September 2021.
Here is my summary of the main recommendations (click here for full report)
- The ‘policy position’ emphasises the need for more research, more research, more research! The policy statement strongly suggests that not enough is known about these chemicals and how they interact in the environment and with each other as potentially even more lethal cocktails. They advocate assessing the actual risk each parasite poses to humans. This research could highlight if any compounds should be restricted or phased out. the policy statement advises that data on the annual sales of parasiticide products and actual frequency of use on companion animals should be collected, and sales data published annually, as the VMD does for antimicrobials.
- The VMD should review the requirements for environmental impact assessment of companion animal parasiticide products.
- the policy statement strongly suggests being mindful of the potential for serious harm to natural invertebrate populations requires a proportionate and targeted approach to treatment with parasiticides. The policy statement strongly suggests treating only when infected.
- the policy statement strongly suggests that the treatments need clearer instructions. Recommends clearer data sheet so that owners know how to use the treatment and reduce contamination. I’d describe the ‘advocate’ instructions on the packet in the cupboard as barely accessible at all. There is no mentions effect on water courses and no advice as to how long to lay off swimming/washing. As to how to dispose of residue, the leaflet advises to look up local guidance!
- the policy statement strongly suggests much greater personalisation of plan:
- Products that are administered topically should not be selected if pets frequently swim, are having hydrotherapy, or are bathed frequently
- Specialist flea/worm treatment consultations with maybe specialist vet nurses drawing up targeted plans for each client.
- Detailed instructions about disposing of unused products, packaging, faeces and used cat litter trays responsibly.
- Advice to refrain from washing an animal or allowing them to swim for a certain number of days after treatment need to be clearly accessible form the data sheet.
- the policy statement strongly suggests that treatments are too broad spectrum and that this is damaging. Wherever possible, veterinary professionals should use targeted and specific treatments. Recommends an increased range of individual products to enable more appropriate treatment of each parasite without the need to overuse another medication. This principle is already in use for grazing animals through the Sustainable Control of Parasites in Sheep (SCOPS) and Control Of Worms Sustainably (COWS) initiatives.
- the policy statement moots reclassification of treatments so that they are better controlled – maybe just on prescription not over the counter
The report acknowledges that prophylactic treatment for parasites often forms part of veterinary practice health plans for small animals, which provide important income for veterinary practices whilst providing clients with peace of mind. It goes on top acknowledge that moving away from blanket treatment will pose challenges to veterinary practices, but goes on to suggest that if the monthly clubs were adjusted they could be pet, vet, client and planet friendly. Not doing blanket parasiticide treatments may help to ensure affordability, as clients are not buying so much in the way of parasiticide products. In-clinic risk assessments and laboratory testing would be helpful for practices working to adapt their health plans. In this way, health plans can be restructured to ensure costs continue to be spread out and affordable over time, customer loyalty can be maintained and vet practices can still makes money..
Use evidence-based infection control measures and minimise ecotoxic chemicals
The policy statement acknowledges that all this will also add to workloads for already stretched veterinary teams, and the additional time needed could have cost implications for clients, however, the report isn’t down hearted, rather it highlights how this challenge that has been successfully overcome in the large animal sector. In the policy statement the BVA, BSAVA and BVZS offered to support vets through this process as they did for the livestock vets in the past.
What can we do? If you are going to use the treatments, be targeted and effective in their use:
- Talk to your vet. Share this article with them
- Keep your furry friends in tip top shape so that their natural immune system shuffles parasites off. Think, diet, exercise and mental health.
- Only treat them if they have a fleas or worm infestation not prophylactically
- Do regular worm counts (Wormcount.com recommend every 3 months). If you know your pet has worms you will then be in a position to choose how to treat them. Worm counts are expensive relative to the cost of a wormer but still probably work out cheaper than a monthly pet club along with an over the counter wormer – see safe disposal of pet waste
- When treating, use gloves, soak up spillages with tissue paper and bin. Here in Shrewsbury we have an incinerator. This has to be pretty safe.
- If you wash your dog (or cat!) or they swim, don’t use a spot-on, use and orally administered treatment
- Find out how long these chemicals take to leave our pets bodies so that we know how long to be careful about their exposure to the biosphere. For this you have to contact the manufacturer. I’d say this info ought to be readily available from the data sheet.
- Don’t wash or allow your pet to swim in this time if you’ve used a spot-on
- Pick up all poo and ensure it goes in the rubbish bin for municipal disposal until it’s safe for the environment
- Many of us have pet poo composters (see environmentally disposal of disposal of pet waste). We need to know when it is safe to start putting poo back on. Many people will unwittingly kill the micro organisms and worms in their wormery’s and composters.
Vet sustain: Greener Veterinary Practice Checklist point 3 states:
- practice responsible antimicrobial and parasiticide use
- Avoid drug wastage through good stocking pro=inciples
- Dispose of drugs correctly (avoid ecotoxicity)
The soil association advises that where five or more horses are kept, the use of avermectin-based products for the control of worms must be limited. No restrictions apply where less than five animals are kept but in all cases animals must be housed or dung removed from the pasture for 48 hours after treatment with avermectin products.
There are alternatives: Nick Thompson https://holisticvet.co.uk/ is, like me, totally against monthly flea and worm treatments. He is confident that the alternatives listed below work, but that owners must be totally ‘on it’ when defleaing and worming ecologically. He would like to see spot-ons only used for infestations.
Nick Thompson says, to treat holistically, you have to be TOTALLY ‘on it’.
- Do worm count and only treat as needs be.
- Educate yourselves as to the early signs of a flea infection – I’ve always noticed flea dirt at the base of the tail black under my finger nails
- Diatomaceous earth. kill fleas can put it on pet and in carpets and sofa. The tiny, sharp particles break down insect skin and kills them. Only use the ‘food grade’ stuff as there is a risk that if the poor quality stuff is inhaled it can do the same as it does to insects to lungs! It’s a bit messy.
- ‘Cedarcide’ spray and ‘billy no mates’ both work as a deterrent and once fleas are present.
- Ticks. Have a tick tool, check for ticks after walks and remove them
Verm-x is a product for dogs and cats containing a blend of herbs to help dogs and cats deter parasites by boosting condition and immunity. It aims at helping to promote skin and coat condition thus deflecting fleas and tick. Your dog will be able to run free with the confidence that they aren’t picking up any extra passengers. Our dogs love ‘em as treats.
Frankie, her mum and litter mates had fleas in the litter. My friend, Penny, who bred them combed all the pups through with claggy coconut oil which puts the fleas out of action and kills them. Every time Penny set out to flea the whole litter, something always came up just as she was getting to the last pup thus, the process become like painting the forth road bridge! When Frankie came to us, I found a flea or two and we treated her bedding with diatomaceous earth and no chemicals and they were immediately and effectively dealt with.
Conclusion: I have always treated minimally. I don’t like putting horrid chemicals on our pets, it’s cheaper and better for the environment. It’s all very well for me to go all righteous indignation, I remember having a conversation with a holistic vet about 10 or so years ago about Daisy and her proclivity to swim and I asked the vet which product to use and she recommended ‘advocate’ as she thought it was more stable in water. Neither she nor I thought about the implications for the environment. She is now a regenerative farmer as well as holistic vet and I’m writing this.
However, once I did know I became compelled to do something about it – hence this article.
Treating pets monthly for fleas and worms is a problem for the biosphere;
If we are going to use chemical agents then we need to use them sparingly:
- keeping your pets in tip top health so that their immune system is strong will help prevent infestation.
- Only treat if have parasites:
- Flea/tick check
- Worm count
- If going to treat prophylactically, assess risk if running around all day in bracken and scrub where sheep and deer abide, a dog will be more likely to pick up ticks for example, whilst and indoor cat might not have the strongest immune system but will be sheltered from infection.
- Read instructions, apply properly and dispose of safely
- Don’t wash or let your dog swim after a treatment
- Don’t leave treated faeces in the environment or in your dog poo composter. Bag it bin it in your municipal bin (and ideally incinerate it – unless incineration then turns into something even more toxic aarrrhhh…)
So whilst this is an emergency, we can do something about it immediately ourselves in changing the way that we care for our own pets and communicating this desire to our vets. I expect that vets should be able to adapt if their parent companies are willing. I’m not so sure about the big pharmaceutical companies!
It’s great that the vets are up for change and it’s great that there is vet activists on this vetsustain but won’t be fast government aren’t going to ban any time soon so it’s up to us, guys. But this is good as this is empowering for us!
https://vetsustain.org/resources/the-environmental-fate-of-pet-flea-products