The permethrin problem

With the number of Lyme disease cases increasing each year, a pressing question looms: are Canadian outdoorspeople being shortchanged by not having access to permethrin as a protective tool? Permethrin is a synthetic insecticide modeled after pyrethrins, which are naturally derived from chrysanthemum flowers. It targets the nervous system of ticks that come into contact with treated fabric, causing paralysis and eventual death. Permethrin spray has been approved in the US for tick-repellent use on clothing for more than 30 years. Since 2003, clothing pre-treated with permethrin has also been available and widely used, remaining effective through dozens of washes. Research suggests that the chemical binds well to fabric and is not easily dislodged. “Permethrin is one of several options for tick-bite prevention and while it would definitely be helpful to have it approved in Canada, it is also important to be aware of its proper use and its potential for harm to animals and small children,” said Dr. Sarah Keating, a board member of CanLyme — a national, volunteer-based organization dedicated to promoting research, education, diagnosis, and treatment for Lyme disease and related illnesses. In Canada, permethrin is already used in lice treatments, pet and livestock products, and various pesticides. However, only one product — Mark’s No Fly Zone pre-treated clothing — has been approved for human use in tick prevention. That approval process took 12 years, and notably, the clothing is not available in camouflage. In the US, testing of permethrin-treated clothing even included assessments of children mouthing the fabric, which was deemed safe. However, the Environmental Protection Agency also raised concerns that permethrin could be carcinogenic if ingested. To be approved for use in Canada, any chemical must be registered through the Pest Management Regulatory Agency (PMRA), which requires the manufacturer to submit comprehensive scientific data to evaluate potential risks to human health and the environment. While Health Canada states that new approvals can take up to two years, this contradicts the 12-year timeline reported by Mark’s. When asked why Canadian approval is so rigorous even for products already assessed in the US, Health Canada spokesperson Anna Maddison said the PMRA monitors the status of chemicals in other countries and jurisdictions but has to conduct its own assessment. “All pesticides used in Canada must meet the Pest Control Products Act requirements and its regulations,” she said. “Before a pesticide is registered for use or sale in Canada,