One of the most mind-boggling choices dog and cat owners face is how to safely guard against fleas and ticks. Those creepy crawlers aren’t just gross; they can transmit disease to both pets and people. Pets need protection, but many of the solutions on store shelves are loaded with chemicals that could be risky to their health—and yours.

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So what’s a responsible pet lover to do? The key is to stop the U.S. Environmental Protection Agency from allowing these harmful products to reach store shelves in the first place. Until the EPA does this, however, you can educate yourself about the risks and benefits of various treatment options, then bring that knowledge to the store. There are ways to keep all your family members, including the furry ones, safe from dangerous pests and the most toxic ingredients.

The perils of pest protection

Most conventional flea and tick products—including collars, topical treatments, sprays, and dusts—are registered as pesticides and regulated by the EPA. (Those given orally, like pills, must be approved by the U.S. Food and Drug Administration.) But here’s the ugly truth: Many of the pesticides allowed for use on pets are linked to serious health issues in people, such as cancer and neurological and respiratory problems. Pets can also suffer: Skin irritation, neurological problems, gastrointestinal disorders, and even organ failure have been reported as a result of pet poisonings.

The government has faced criticism from NRDC and other watchdog groups about insufficient safety standards for these products. Consumers, as well as some veterinarians, don’t know the whole story, says NRDC senior scientist Miriam Rotkin-Ellman. “Many vets count on the EPA to make sure that the products on the market are safe if used correctly.” Unfortunately, the ingredients in these products are still quite dangerous, and regular use can result in unsafe exposure, particularly for children and pregnant women.

For example, even low-level exposure to organophosphates and carbamates—two particularly dangerous families of pesticides found in some flea treatments as well as in agricultural and lawn products—have been linked to learning disabilities in children. For this reason, most household uses of these pesticides have already been banned. Unfortunately, kids can still be exposed to them from their furry siblings' flea collars or other products.

Going nontoxic. Fortunately for many families, fleas can be controlled without resorting to harmful chemicals. Always try the strategies below first before considering chemicals—safer chemicals—if additional protection is needed. Here’s what you can do:

Groom your pets regularly. Common soap and water will kill adult fleas. In addition, comb your animal’s fur with a fine-tooth flea comb, and dunk any critters into a container of sudsy water.

Clean, clean, clean. Wash your pet’s bedding weekly in hot, soapy water, and vacuum and wipe down pet-frequented surfaces often, including behind and underneath furniture and between couch cushions. If you’re the victim of a flea infestation, Karyn Bischoff, a toxicologist at the Cornell University College of Veterinary Medicine, recommends doing this daily. For severe cases, professional steam cleaning may be needed for your carpets.

Take preemptive steps in your yard and garden. It helps to put beneficial nematodes—worms that eat flea larvae—in the soil where your pet is likely to frolic. Find them in garden supply stores or online.

Diatomaceous earth is a less toxic option for the home and yard, says Rotkin-Ellman, “but it can be really damaging if it is inhaled or gets into your or your pet’s eyes.” Use caution and protective gear, and use it only in areas where pets and kids won’t be exposed. Look for products marketed to control pests, and avoid the kind used in swimming-pool systems.

Be wary of products marketed as “natural.” Sadly, there’s no magic nontoxic bullet to wipe out these pests. Natural products and herbal remedies should also be approached with caution. They may not work—and some aren’t safe, says Bischoff. Many of these contain peppermint, cinnamon, lemongrass, cedarwood, or rosemary oil. While these may be safer than some of the synthetic chemicals, they have also been linked to allergies in both pets and humans, and not much is known about how well they actually work. If you give these a try, monitor your pet and family closely for adverse reactions.

Considering chemicals

There are varying degrees of danger when it comes to these products and the chemicals they contain. Work with your vet to craft a custom plan for your pet, and keep some basic guidelines in mind to spot safer products:

Ask about oral flea-prevention treatments. Pills with the active ingredients lufenuron, nitenpyram, or spinosad can be a better option, for both animals and humans, than treatments that leave residue on fur that might get on hands or furniture. But oral meds need to be prescribed by a vet and are considerably more expensive, so they may not be a realistic option for all pet owners.

Identify safer ingredients. If chemical products are necessary for additional flea or tick control, NRDC recommends s-methoprene or pyriproxyfen, which are less toxic ingredients—but read the labels carefully because some products use them with other, more harmful pesticides. Avoid products that include synthetic neonicotinoids (like imidacloprid and dinotefuran), which are harmful to bees and may be toxic to the developing brain of young kids.

Be wary of flea collars. These products can contain some of the most dangerous insecticides, including tetrachlorvinphos, carbaryl, and propoxur. Some of the collars posing the greatest risk are already being phased out of production, and NRDC is suing the EPA to ban the rest. Until that happens (and until older products are off store shelves entirely), either avoid collars altogether or be vigilant about searching labels for those particular active ingredients.

Use extra caution with tick products. When it comes to tick prevention—or combination flea-and-tick products—the news is even grimmer. Most products designed to repel these buggers include possible carcinogens and nervous-system toxins like fipronil, permethrin, pyrethrins, or imidacloprid. “Our recommendation for ticks is to use the least toxic option available, at the lowest level, and only when you need it,” Rotkin-Ellman says. If you live in an area where ticks and Lyme disease are prevalent, you probably need protection—but talk to your vet about how much and how often. Pregnant women and young children should minimize their exposure.

Buy a species-specific product. Two common ingredients in flea-and-tick products, permethrin and pyrethrins, are very toxic to cats. Don’t put these ingredients on your dog, either, if you also have a cat that could snuggle up with or brush against it.

Choose the right formula for your pet’s weight. An EPA investigation showed that small dogs (10 to 20 pounds) were most likely to have reactions such as rashes, vomiting, diarrhea, and seizures from topical treatments. Dogs that are old, young, sick, or on meds are also at higher risk. (Flea and tick control can interfere with other medications, rendering them ineffective or even poisonous.) There are even breed-specific sensitivities, so a conversation with your vet is in order before you decide how to proceed.

Don’t rely on shampoos. Flea and tick shampoo may seem like a safer, more cost-effective option, but they often contain many of the same ingredients as topical treatments and can cause adverse reactions and allergies, Bischoff says. Moreover, they’re not meant to take the place of preventive options. “You’d use a shampoo for an animal with an infestation and then, usually, follow up with a topical treatment,” she says. Read labels, and take the same precautions with shampoos as you would with spot-on or collar products.

Report health issues immediately. If you or your pet reacts to a pet product containing pesticides, call your local poison control center, talk to your doctor, and, later, report it to the National Pesticide Information Center at 800-858-7378.