Over the years, the lice have become resistant to many pesticides treatments. The 100% natural APSIRON products are the only effective solution against these new strains of lice. Studies in recent years suggest that up to 75% of the lice are now resistant to permethrin, and pyrethroids, the active ingredients which are currently on the market in many anti-lice products. The most important is that the treatment for head lice should be safe for your children. Unfortunately, the anti-lice products on the market today are anything but safe. The Environmental Protection Agency in 2009 classified permethrin as a "possible carcinogen to humans." The American Association lice, a nonprofit group that studies and analyzes lice issues in terms of addressing products on the market, has collected over 1,000 reports linking the use of insect repellent shampoo with seizures, behavioral problems, and leukemia. Protect their health! Eliminate lice & nits!