Permethrin is one of the leading tick prevention products on the market, but as with all chemicals, it is a cause for concern with some people who are worried about the potentially negative effects of this chemical on their health or that of their loved ones, including their pets.
What is Permethrin?
Permethrin is a synthetic insecticide which is used to control insects in livestock and in pets, as well as in crops, ornamental gardens, and even restaurants. It is also used in clothing to repel insects.
It is often used in flea and tick prevention, such as flea and tick collars and spot treatments for pets. In humans, it is used to treat scabies and other conditions caused by mites, and to get rid of lice.
Permethrin affects insects if they eat or touch it. It targets their nervous system and causes muscle spasms, paralysis and death. Permethrin is more toxic to insects than it is to people and dogs because insects can’t metabolize it as quickly. Cats are more sensitive to it because it takes them longer to break it down, but it is still considered safe.
Safety Considerations
It is generally considered safe. However, an increasing number of people have reported allergic reactions in themselves and their pets. It is highly toxic to fish and even small amounts will pollute the water supply, which is why those who use it on their pets are told not to wash them for several days after they have given them a treatment.
Permethrin All Around
Permethrin is so commonly used now that it is easy to be exposed to them on food you eat, like fruits and vegetables, and coming into contact with your pet’s flea and tick treatments.
It is also used as a fogger to treat crops and cut down on mosquito populations, such as in areas with standing bodies of water, where mosquitoes will typically breed. This means it is possible to breathe it in, or even get it in your eyes.
You might also eat it if you touch a product with permethrin on it, don’t wash your hands, and then prepare food and/or eat with your fingers.
The Safety Profile
The FDA has studied permethrin and concluded that it is likely to cause cancer if eaten. It will usually trigger nausea and vomiting.
People who have breathed in permethrin report irritation in the nose, throat and lungs, difficulty breathing, headaches, dizziness, nausea and vomiting.
Cats who have accidentally licked a solution with a high percentage of permethrin have experienced drooling, spasms and even death in some cases. Dogs and cats have also been reported as twitching, rolling on the ground, and shaking their paws. They might drools, smack their lips, or generally act as if they have tasted something bad.
In lab animals such as rats, permethrin was shown to be eliminated in the urine within a few hours. Dogs and mice fed it regularly in experiments over a period of 2 years were more prone to fatty livers and tremors or spasms.
Rabbits got skin irritation from topical treatments, but did not suffer any other ill effects. Pregnant rats and rabbits fed permethrin were more prone to have offspring with birth defects, and miscarriages.
Other Safety Concerns
Permethrin is broken down by microorganisms in the soil, and by sunlight to a certain degree, but it does not mix well with water and tends to stick to sediment, such as on a river bed, accumulating over time and still active a year later.
If permethrin is applied to plants, it may stay on the leaves for between 1 and 3 weeks.
As with all products, it is a case of buyer beware, and making sure the rewards outweigh the risks. If you are considering using it for flea and tick protection for your pets, for example, be sure to use it exactly as instructed, wash your hands afterwards, and keep an eye out for any unusual behavior after applying it.
To learn more, see: http://npic.orst.edu/factsheets/PermGen.html
