ATSDR | Toxicological Profile for Disulfoton

Disulfoton (o,o-diethyl s-[2-eththioethyl] phosphorodithioate, CAS No. 298-04-4, Di-syston) is a systemic organophosphate insecticide/acaricide. It is a manufactured substance and does not occur naturally. Disulfoton was canceled by the Environmental Protection Agency (EPA) in 2009 for use as a pesticide, as a result of its toxicity (EPA 2010). Remaining stocks were permitted to be sold until 2011, and its use in U.S. agriculture has been reported as recently as 2016 (USGS 2020). Previously, disulfoton had been used to protect many field and vegetable crops from a variety of harmful insects. As a result of its canceled use and rapid degradation in air, water, and soil, the potential for human exposure is low. Inhalation and dermal exposures to disulfoton are low for the general population, and exposure in drinking water is likely negligible. Levels of disulfoton in environmental media are also expected to be low. People who manufacture, handle, or apply disulfoton or who are involved in the disposal of disulfoton are at a higher risk of exposure than the general population, though occupational exposure is expected to be low to negligible in the U.S. since its cancellation. People who live near disulfoton manufacturing or processing sites, or hazardous waste sites containing disulfoton are also at higher risk of exposure.