Dioxathion, systematically known as p-dioxane-2,3-diyl ethyl phosphorodithioate, is an organophosphate pesticide. It is used as an insecticide on livestock and as an acaricide on citrus fruits, deciduous fruits and nuts.
Under the trade name Delnav, it can be used to control insects and mites on apples, pears, quince, grapes, and walnuts, and finds use in the control of ticks, horn flies, lice and sheep keds in various livestock, either as a spray or as a dip. Under the trade name Deltic, it is a restricted use pesticide for exterior control of fleas, ticks and mites, in kennels, dog houses, yards, and other recreational areas.
Dioxathion is an Extremely Hazardous Substance, as defined by Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act, and is no longer allowed to be sold in the United States. However, it continues to see use in some other countries. It has been known to cause inhibition of the enzyme cholinesterase in rats, and it is recommended that people who have exposure to dioxathion regularly get their plasma and red blood cell cholinesterase levels assessed. Persons exposed to other chemicals which affect cholinesterase levels, e.g. other organophosphates or carbamates, may be at an increased risk. There are no known carcinogenic or reproductive effects, but long term exposure may result in nerve damage, poor motor coordination, and personality changes of anxiety, depression or irritability.