Toxaphene

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Toxaphene is a pesticide that was widely used on cotton in the southern United States during the 1960s and 1970s. It isn’t a single chemical but a mixture of more than 670 different compounds created by chlorinating camphene. It typically appears as a yellow to amber, waxy solid and does not dissolve well in water, but dissolves in organic solvents. Toxaphene is very persistent in the environment and can remain in soil, air, and water for years, traveling long distances through the air.

Most of the use in the U.S. was on cotton, with smaller amounts used on other crops and livestock pests. Production and use peaked in the mid-1970s; after environmental concerns and regulatory action, usage fell sharply in the early 1980s. The United States banned all uses of toxaphene in 1990, and many other countries banned it as well. Under the Stockholm Convention on Persistent Organic Pollutants, toxaphene was listed as one of the “dirty dozen” chemicals to be eliminated or restricted, with the treaty taking effect in 2004.

People are mainly exposed to toxaphene through contaminated food, drinking water, air, and soil, with seafood being a common source. It builds up in fatty tissues in the body and can be found in blood, urine, breast milk, and tissues after exposure. Health effects observed in animals include liver and kidney damage; in humans, exposure can irritate the lungs and nervous system and, at high levels, may cause death. Toxaphene is considered a probable human carcinogen by major health agencies.

In the environment, toxaphene degrades slowly and can persist for years, especially in soil, sediment, and fatty tissues of wildlife. Regulations set low limits for drinking water and bottled water, and its transport and handling are tightly controlled because it is classified as an extremely hazardous substance in the U.S. Today, some limited uses remain in certain places, but overall toxaphene is largely banned and controlled worldwide.