Lindane is an organo-chlorinated pesticide in the same chemical family as DDT. It has been listed by the U.S. Environmental Protection Agency as a Persistent, Bioaccumulative and Toxic Chemical, meaning that it lingers for a long period in the environment, moves up the food chain, and is toxic to humans and wildlife. Lindane is also a priority pollutant, a hazardous material, and a Bioaccumulative Chemical of Concern.

Lindane is used in a prescription shampoo, often called Kwell, to treat head lice. It is also used in a prescription cream to treat the skin mite scabies. In both of these applications, lindane is applied directly to the human body. Other uses of lindane have been highly restricted in California. It is used as an insecticide on seeds and some plants, but may only be applied by certified pesticide applicators. It may not be applied to animals.

Lindane is a highly potent nerve toxin that is readily absorbed through the skin. Even when used exactly as directed for head lice or scabies treatment, lindane can cause seizures. Labeling information on lindane indicates "Seizures and, in rare instances, death have been reported after excess dosage, over-exposure, frequent reapplications, and accidental and intentional ingestion of lindane." Because parents often panic when faced with cases of head lice or scabies in their children, instances of misuse are all too common. The U.S. Agency for Toxic Substances and Disease Registry reports that lindane can cause liver and kidney damage, immune system damage, toxicity to the central nervous system, and even death. Lindane is known to cause liver cancer in animals and is considered a possible human carcinogen.

The National Pediculosis Association, a non-profit organization dedicated to head lice and scabies education, has set up a database on head lice and scabies outbreaks and treatment. This database has collected over 500 adverse event reports related to the use of lindane in the 24 months it has been in existence. Reported injuries include seizures, brain damage, and birth defects.

Lindane shampoos and creams are rinsed off after use in the sink or shower. When lindane goes down the drain, it makes its way through the sewer to a wastewater treatment plant. Since lindane is not removed well in wastewater treatment plants, it passes through to downstream creeks, rivers, lakes, and the ocean. Lindane is so toxic that the allowable limit for lindane in drinking water sources is 19 parts per trillion. To put this number in perspective, a single treatment of lindane to kill head lice or scabies pollutes 6 million gallons of water.

Sewerage agencies that serve the City of Los Angeles, Los Angeles County, Sacramento County, Sonoma County, the Inland Empire, and the Cities of Woodland, Lodi, Merced, and Vacaville all have excessive amounts of lindane entering their systems. Together these agencies serve 11 million people, representing over 30% of California’s population. More sewerage agencies are expected to be impacted as new, more stringent water quality standards promulgated by the U.S. Environmental Protection Agency in May 2000 are implemented in wastewater discharge permits.

Since lindane usage is restricted, the treatment of head lice and scabies represents essentially the only source of lindane to sewerage systems. The only way to stop lindane from entering sewers and thus water bodies is to stop medical usage of lindane. Otherwise, very costly treatment will have to be installed to remove lindane. The average cost to remove lindane from a single head lice or scabies treatment out of wastewater at a treatment plant is estimated at $4000.

Safer substitutes for the treatment of head lice and scabies are readily available and widely used. For head lice, over-the-counter products based on permethrin and pyrethrins can be used, as well as a prescription product containing malathion. For scabies, prescription products based on permethrin and crotamiton are on the market. The California State Department of Health Services has stated that lindane is less effective and has more potential toxicity than the easily available alternatives. Therefore, there is no reason to continue prescribing lindane for use on humans in California.

AB 2318 will protect human health and the environment by prohibiting the use of lindane in products for the treatment of head lice and scabies, as of January 1, 2002.