Source of Permethrin
In nature, the chrysanthemum plant, Chrysanthemum cinerariifolium, contains a natural insect-repelling component known as pyrethrin. Pyrethrin has been used in insecticidal products for over a century. However, due to high extraction costs, low storage stability, and susceptibility to photodegradation, it was challenging to use extensively. Scientists later synthesized a chemical compound with higher chemical and photo stability by mimicking and modifying the structure of pyrethrin, known as permethrin. Permethrin was synthesized in the UK as early as 1973 and registered as an insecticide by the US EPA in 1979. It is a safe and effective insect-repelling ingredient. Permethrin, being more resistant to sunlight degradation than natural pyrethrin, is well-suited for outdoor use. Its lower synthesis cost and easier control over yield and quality have led to its widespread application in the insecticidal products market, gradually replacing pyrethrin.
Mechanism of Action
Once absorbed by insects, permethrin tightly binds to sodium channels in their nerve cells, disrupting the transmission of nerve signals, leading to paralysis, immobilization, and death in insects. Most insects have developed defense mechanisms against permethrin to protect themselves, making permethrin highly effective in repelling mosquitoes and other insects.
Applications
Permethrin has diverse applications. In agriculture, it can be extensively sprayed in farmlands as a broad-spectrum pesticide to protect crops from pest infestation. It is also applied in livestock farming to combat parasite infestations. In the medical field, permethrin is commonly used to eliminate head lice and treat scabies. In 2017, it was included in the World Health Organization’s Essential Medicines List, recognized internationally as a drug against parasites and insects.
Furthermore, permethrin is currently the only insecticide approved by the US EPA for textiles treatment. It has been used in US military uniforms since the 1990s and is now commonly found in various textile products. Clothing treated with permethrin effectively prevents insect bites from mosquitoes, ticks, ants, fleas, midges, and others, thus preventing transmission of various diseases such as malaria, dengue fever, West Nile virus, and Japanese encephalitis. Additionally, permethrin protects clothing like woolen garments from fiber-eating insects, extending the lifespan of clothing.
Safety of Permethrin
Permethrin is safe for humans. Humans and most mammalian species naturally produce monooxygenases within the cytochrome P450 system, enzymes crucial for permethrin degradation, facilitating its breakdown in the body. Therefore, even if permethrin is inadvertently absorbed by the human body, there are mechanisms to break it down into non-toxic substances. Research indicates that when permethrin is topically applied to treat scabies, less than 0.5% of the total permethrin dose is absorbed, with complete breakdown and excretion within 48 hours. Hence, permethrin does not have a significant impact on human health and is considered safe.
Regarding textiles treated with permethrin, due to the low content of permethrin on fabrics and minimal absorption by the body, clothing treated with permethrin is considered very safe for humans. Many internationally recognized organizations such as the World Health Organization (WHO), the US Environmental Protection Agency (EPA), the Centers for Disease Control and Prevention (CDC), the Public Health Agency of Canada (PHAC), and the National Pesticide Information Center (NPIC) recommend wearing clothing containing permethrin to prevent insect-borne diseases.
Hansk New Materials boasts over 20 years of experience in applying permethrin to textiles. We have successfully addressed numerous technical challenges, achieving consistent high-quality results. Our EPA-registered products Vital Protection® ensure the safety and efficacy of treated articles. Through continuous research and improvements over the years, Hansk’s anti-insect treatment have become increasingly mature. In terms of durability, even after 70 washes, the insect-repelling effect of Hansk-treated products remains impressive, providing users with long-lasting insect protection.