ABSTRACT
Release of disulfoton to the environment probably occurs primarily during its use as an insecticide in crops of tobacco and edible foods including carrots, cucumbers, parsley, peas, and potatoes. The amount of disulfoton used annually in the US prior to 1983 was estimated in 1985 to be greater than 2.1 million pounds. If released to water, disulfoton will be oxidized to its corresponding sulfoxide and sulfone by reaction with photochemically generated singlet oxygen and possibly hydroxyl radicals. Disulfoton may be susceptible to biodegradation in natural waters based upon apparent observation of biodegradation in some soil studies; however, studies in sterilized and nonsterilized soils have led to somewhat conflicting conclusions with regards to differentiation between chemical and biological degradation of disulfoton in soil. Disulfoton was rapidly oxidized to its sulfoxide and sulfone in upland soil and was oxidized even faster in flooded soil, but transformation was very slight in sterile soil suggesting biodegradation was significant in unsterilized soils.
