As an organic grower, I very rarely put pesticides in my garden (exception made for wasp nests), and as an herbalist, I avoid putting pharmaceutical chemicals in my body. As a dog trainer who enjoys a snuggly dog or two in the bed, you might imagine I learned to tolerate fleas. Nope! We have modern day chemicals that are truly effective and non-toxic, that allow us to control fleas very effectively and easily, without too much poisoning of ourselves or our environment.
Like head lice on humans, the battle with flea must be won decisively. Not only because flea bites are itchy, and the sound of a dog scratching drives me up the wall, but because fleas (like ticks) host diseases that can be transmitted to humans. Most commonly in our neighborhood, fleas transmit tapeworm. The dogs get the tapeworm from eating a flea, and then the human baby could also get the tapeworm when she sucks on a toy that contaminated with tapeworm eggs off the dog. Icky as that is, it could be worse. In other regions of the world, fleas have transmitted plague, and ebola-like diseases.
But pesticides aren’t risk free either. Exposure to pyrethrin products and other neurotoxic chemicals has been strongly associated with later development of Parkinson’s disease. Organophosphates can penetrate the blood brain barrier and influence animal behavior, as well.
Topically applied pesticides are generally absorbed and then excreted in active form in a dog’s feces. Genetic deformities of frogs and other creatures in the great lakes regions has been associated with S-methoprene (in Frontline plus), and other hormone mimicking pesticides in the environment. Fipronil (also in Frontline Plus) breaks into components that are many times more toxic when exposed to sunlight, and although many of these flea and tick products are listed as “waterproof” that’s not entirely true. They are washed off and rubbed off when our dogs are petted, bathed, swimming.
The Natural Resource Defense Council recently produced a report on the dangers of these chemicals to human health (see resources) and they show that typically children carry the most dangerous loads of these unintended chemical exposures. And many of the effects and actions of these chemicals are unknown. While risk of cancer or neurological disease if used as directed might be slight, skin sensitivities, allergic reactions, autoimmune disease, behavioral and other risks related to exposures are not well understood.
To add insult to injuries, as bacteria become resistant to antibiotics, pests over time become resistant to pesticides. Take for example Frontline Plus (containing fipronil and S-methoprene,) or ProMeris. Companies which sell these products site studies found an initial 90-98% kill rate of the fleas and eggs, with reduced effectiveness over the course of a month as dogs swim or are bathed and the product wears off. That means more than 5-10% of fleas survive. Just one of these naturally more pesticide-resistant-fleas can lay 2000 eggs within two weeks. Each surviving generation is genetically more resistant to the chemicals. Some studies say it can take only six generations until a local strain of fleas is completely resistant to a pesticide.
In the Midwest, where farmers apply long-lasting pesticides to kill ticks on cattle, they are seeing pesticide resistant ticks. Here on the Maine island where I live, pesticides work against ticks, but we have a population of fleas which is not even nervous around Frontline.
Happily,lufenuron doesn’t work by killing, but you feed your dog a monthly lufenuron pill, and when fleas bite your dog, they can’t lay viable eggs. Completely non-toxic to humans and dogs, fleas also don’t become resistant to the action, and it can’t wash off. Lufenuron is sold as “Program,” and sold in combination with some heartworm medications such as Sentinel.
We give lufenuron year-round in Sentinel, which also treats to prevent heartworm, whipworm, roundworm, hookwoom. Bagging feces and disposing for incineration will help prevent any surviving parasitic worms (and flies) from reproducing in our environment, as well as collect any chemicals that might be excreted.
Typically, lufenuron is started in combination with a Capstar pill. Capstar kills the fleas on your dog within a couple of hours, and can’t rub off on you or your family. When the snow is gone, if I take my dogs into areas where they might run into ticks, I apply a topical poison for ticks, but otherwise, the monthly dose of Lufenuron, and the rare dose of Capstar (after a flea-infested play-date) provides us with a flea-free environment.
If you use pesticides on your pets and you don’t also use lufenuron, beware! Your surviving fleas are breeding a colony of pesticide resistant fleas.
At Whole Dog Camp, I now require all canine participants to be on a lufenuron treatment program. Even if that is the only chemical my clients use, it means fleas can’t breed here. If all islanders used lufenuron, within just a couple of years, island fleas would all be dying of old age.
Natural Resources Defense Council. David Wallinga, M.D., M.P.A., and Linda Greer, Ph.D. Poisons on Pets: Health Hazards from Flea and Tick Products, 2000
Kaplan, Melissa Pyrethroids: Not as safe as you think http://www.anapsid.org/pyrethroids.html 2007
BioControl and Biodiversity, Grasslands Division, AgResearch, Lincoln. Travis Glare and Maureen O’Callaghan Report for the Ministry of Health: Environmental and Health Impacts of the Juvenile Growth Analogue S-Methoprene, http://www.moh.govt.nz/moh.nsf/0/FF3B628D67E34963CC256BA3000D8476/$File/s-methoprene.pdf 1999