Chemicals and dogs

Modern-day life puts all of us (dogs and humans) in direct contact with hundreds of chemicals each day. And it’s not good. Possibly the most common source of pesticide exposure –and overexposure—for dogs are flea, tick, and heartworm preparations. In some cases these chemicals are a blessing, ridding the dog and house of tormenting pests. But we’ve been taught to apply these chemicals to our pets every month of the year. Is it necessary? Below is an excerpt from my book, Canine Epilepsy. At the end are some more wholesome options for pest-control.

Chemicals, Pesticides, and Wormers

Increasing evidence suggests that environmental chemicals contribute to neurological, endocrine, and immune system dysfunction. Many chemicals break down into free radical molecules. They steal electrons from normal molecules in the body. This causes damage in various forms. Free radicals fuse the fatty acids in cell membranes, making them less permeable. They break off identification proteins in cell membranes and damage cells of the immune system, both of which may contribute to autoimmune disease. Free radicals damage cell nuclei, disrupting the DNA material found there.

It is common practice to use powerful pesticides on or near our pets. Some, such as flea bombs, carpet powders, weed killers, and garden pesticides, saturate the dog’s environment. We place others directly on our pets: Flea collars, shampoos, and drop-on repellents that are so potent they persist for many months. And some, including heartworm medications, we give our pets internally. Keep in mind that the product labels instruct humans to wear gloves and wash their hands thoroughly after contact with these chemicals.

Phenols are a class of industrial chemicals used as a flavor enhancer in pet foods and found in aromatic cedar products and pine cleaners. Phenols, as well as a number of yard and garden herbicides and insecticides, are classified as endocrine disrupters. Researchers have found that phenols attach to brain cells instead of appropriate hormones such as thyroid hormone. This disrupts normal endocrine (hormone) activity.

The federal Environmental Protection Agency (FDA) has identified roughly 140 pesticides as neurotoxins. Included in this classification are a number of the chemicals commonly used to kill fleas, ticks, and heartworms. These chemicals act upon the brains of pests in order to kill them. Some chemicals act on the nervous system of mammals in exactly the same way they act upon insects. They interfere with biochemical brain activity, resulting in hyper-excitability and seizures.

Pet owners believe these preparations must be safe if they are sold in grocery stores or recommended by veterinary professionals. The law that regulates pesticide use — the Federal Insecticide, Fungicide, and Rodenticide Act — does not use safety as the measure for allowing a pesticide on the market. Instead, a risk-benefit standard is used. If the pesticide has potential benefits, it may be approved for use regardless of the hazards.

It is both fascinating and disturbing to note the relationship between pesticides and kindling, the phenomenon in which the brain’s electrical pathways become increasingly established with each seizure. The more developed the pathways, the greater the likelihood that seizures will recur. Laboratory animals are exposed to low-level pesticides in order to test and initiate the kindling response. Many pesticides, including pyrethroids, increase seizure activity.

Look around your house and examine your daily routines. Are there other house and garden chemicals that can be reduced or eliminated? Try to minimize the general load of chemical insults: Fabric softeners, dryer sheets, floor polishes, air fresheners, carpet-cleaner powders, spray on/brush out pet shampoos, insect repellant, weed killers, and furniture stain repellants. Living a more chemical-free life is beneficial for both you and your pets.

Store bottles and boxes of chemicals and poisons up off the floor and out of reach. This is especially important for curious puppies in their developmental stages. Prevent your dog from accessing areas sprayed with agricultural chemicals–pesticides, fungicides, and herbicides– for at least 24 hours and 48 hours is better. 

Heartworm Prevention

In certain parts of the world, the threat of heartworm infestation is very real. Warm climates provide the right environment for mosquito populations, the carriers of heartworm larvae. If you do not live in a high risk area, or wish to reduce the chemical insult to your dog, there are other methods of preventing serious injury or death from heartworms.

Transmission of heartworm is dependent upon the lifecycle of the mosquito. Studies indicate that daily, average temperatures must exceed 64 F (18 C) for approximately one month, in order to support the mosquito lifecycle. Another source suggests that temperatures must exceed 80 F (27 C) for at least two weeks. If temperatures fall below 57 F (14 C), the lifecycle is interrupted. Using these guidelines, it may not be necessary to treat for heartworms year round, in all locales.

Heartworm medications are treatments not preventatives. They slowly kill circulating larvae. They do not prevent the dog from contracting an infestation in the first place. With that in mind, some dog owners begin treatment one month after temperatures reach 64 F and continue until one month after temperatures drop below 57 F.

Other owners don’t use any medications and simply test twice yearly. However, routine testing is crucial to prevent infestation. Without these twice-yearly checks an infestation can become uncontrolled and life-threatening. If the test results are positive, your veterinarian will likely take an x-ray to determine the level of infestation. Mild infestations caught early are often treated with the same medications used on a monthly or daily basis. These are sometimes termed “slow kill” medications. Advanced infestations are much more serious, requiring treatment in the veterinary hospital. This may include “fast kill” medications and IV fluids.

Flea and Tick Control

There are many options for more wholesome flea and tick control. Vacuum one to three times, weekly. Wash the dog’s bedding frequently. Use a flea comb regularly, dipping the comb into a bowl of soapy water to drown any fleas you find. Most soaps will kill fleas. Ticks can be held in a tweezer and lit with a match or lighter.

Bathe your dog regularly but avoid shampoos that contain pyrethrins. Although these are specifically designed to kill fleas they do so by interfering with neurological function. There are ever-increasing numbers of herbal repellants and natural shampoos available. Try a few drops of peppermint, rosemary, or lavender oil on a towel. Quickly swiped it over the dog’s coat before you go into wooded areas to repel ticks.

Control flea populations by keeping lawns short and leaves raked. Apply predatory nematodes (simple roundworms that devour insects) or diatomaceous earth (a calcium dust that acts as a natural insecticide) to lawns. These are available at many garden centers.

Cedar chips should be used with some caution. Cedar, like pine, contains phenols ­— chemicals known to disrupt endocrine function and lower the seizure threshold. Be alert for the presence of cedar chips in commercial kennels and pet beds. Be sure to evaluate your dog’s physical condition if you introduce cedar chips to the environment. Certain sensitive individuals may exhibit increased seizures, and young puppies may exhibit allergic symptoms to cedar.

Certain dietary supplements may be helpful in discouraging fleas. These include B vitamin complex and small amounts of garlic. And don’t forget the basic benefits of a more-natural diet. Pests tend to infest animals that have diminished resistance. Dogs are compromised when fed difficult-to-digest commercial food. It weakens their immune system. Owners treat the resultant infestations with chemicals that likely worsen their immune system and neural function. Many owners report reduced flea problems after a switch to fresh food.

If you absolutely must use pesticide flea treatments on your dog, try to prolong the period between applications. It may be possible to apply a product only several times yearly rather than every thirty days. 

Here is a good article on pesticide exposure in case you think your dog has been poisoned: