Primary methods of endrin disappearance from soil are volatilization and photodecomposition. These include&colon; aldrin, chlordane, DDT, dieldrin, endrin, heptachlor, mirex and toxaphene. In 1970, Japan imported 72,000 kilograms of endrin. Some of these pollutants are DDT, aldrin, chlordane, dieldrin, endrin, heptachlor, hexachlorobenzene, and toxaphene. The synthesis of endrin begins with the condensation of hexachlorocyclopentadiene with vinyl chloride. Endrin is a stereoisomer of dieldrin. Symptoms of endrin poisoning include headache, dizziness, nervousness, confusion, nausea, vomiting, and convulsions. Acute endrin poisoning in humans affects primarily the central nervous system. Insecticides like dieldrin and endrin have been shown to persist for decades in the environment. Endrin was used globally until the early 1970s. J. Hyman & Company first developed endrin in 1950. Endrin was manufactured as an emulsifiable solution known commercially as Endrex. In the United States, endrin has been regulated by the EPA. In addition, endrin has been employed as a rodenticide and avicide. Endrin was banned in the United States on October 10, 1984.