Toxaphene is an insecticide which was primarily used on cotton and other crops, but was also used to control insects on livestock and to kill unwanted species of fish in freshwater lakes.
It is composed of over 670 different chemicals, and is a yellow-to-amber, waxy solid which smells like turpentine. It does not dissolve easily in water and cannot be burned. When dissolved (in nonpolar solvents), it vaporizes and can enter the atmosphere. It is not found naturally in the environment.
Toxaphene was banned from use in 1982 in the United States by the Environmental Protection Agency, except for limited use on livestock and in emergencies. Toxaphene exposure can cause damage to the lungs, nervous system, liver, and kidneys. Large doses can be fatal. It is also possible that toxaphene increases the risk of cancer and causes birth defects when pregnant women are exposed to it.
The information in this writeup was taken from the science dictionary at http://biotech.icmb.utexas.edu/; I oversaw the development of the dictionary (the website was mothballed in 1998) and I believe I wrote the entry this is based on.