What are the Safest Flea Treatments for Pets?

#EcoAdvice from our expert

Dear Dr. Donley,

I recently found out my dog’s flea collar contains a toxic neonicotinoid pesticide. Aren’t neonicotinoids the pesticides that are driving declines of bees and other pollinators? Are there any safe flea treatments out there for pets?


Itching to Know

Dear I2K,

Yes, unfortunately, those are the bee-toxic pesticides. So kudos to you for looking for ways to keep our bees safe at the same time as you keep your dog free of pesky fleas.

Deciding on a flea or tick treatment can be tough. Fortunately many pets go through their whole lives without any major problems with these pests. Preventative measures, such as keeping your house clean of hair and dust, regularly bathing your pet, and ensuring that he or she gets a healthy diet and plenty of exercise can go a long way in preventing infestations, and these measures should always be taken regardless.

But some pets, like my dear old dog, have extreme allergies to fleas, and others are prone to infestations. Also, if your pet is regularly outdoors — where there are large populations of disease-carrying ticks — a regular flea/tick treatment may be a necessary precaution to maintain your pet’s quality of life (and your sanity). Some ingredients in flea and tick treatments stand out as worse than others, but none should be considered completely harmless.

Unfortunately the EPA, which regulates pesticides, has long had systemic problems that result in dangerous products making it to store shelves. This is true for pesticides used on our food as well as pesticides used on our furry friends. Neonicotinoids like imidacloprid and dinetofuran are present in some flea and tick treatments. When you bathe your pet after a topical treatment, the chemical gets washed down the drain to wastewater treatment facilities where, it has been shown, nearly 100 percent of it makes it through the filtration process and gets dumped into our streams, rivers and oceans. Increasingly scientists are discovering that neonicotinoids aren’t just dangerous for bees — they also pose an extreme threat to aquatic invertebrates and the ecosystems that rely on them. So giving your dog a bath isn’t just misery for your dog (and you), but also can cause real harm to nearby ecosystems when the dog has been treated with a neonicotinoid.

In addition to affecting the outside environment, pesticide residue from treated pets can rub off on your hands after petting and will likely be perpetually present in the dust in your home. Ingredients in some flea treatments, like tetrachlorvinphos, propoxur, fenoxycarb and carbaryl, are potent neurotoxins that can harm the development of young children. Since children are often low to the ground and put their hands in their mouths often, this can lead to a high level of exposure.

Other ingredients, like amitraz, fipronil, permethrin, tetramethrin, cypermethrin and bifenthrin, have been classified as likely or possible carcinogens by the EPA. I would recommend not using any of the ingredients mentioned above on your pet. Just check out the ingredient list on the back of the box.

But not to worry, you don’t have to live with an itchy dog. You’ve still got plenty of options. Ask your vet about oral medications for fleas. In general, oral medications are preferable to topical treatments or flea collars. And do not treat your cat, or any dog that lives with a cat, with any pyrethroid or pyrethrin compound as they are extremely toxic to felines. Always double-check with your veterinarian.

And, of course, to channel my inner Bob Barker — be sure to get your pet spayed or neutered!

Stay wild,

Dr. Donley

Dr. Nathan Donley is a scientist at the Center for Biological Diversity who answers questions about how environmental toxins affect people, wildlife and the environment. Send him your questions at AskDrDonley@biologicaldiversity.org

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