Tests involving acute exposure of animals, such as the LC 50 and LD 50 tests in rats, mice, and guinea pigs, have demonstrated dimethyl sulfate to have high to extreme acute toxicity from inhalation and high acute toxicity from oral exposure. EPA has not established an RfC or an RfD for dimethyl sulfate. The first study did not report a statistically significant increase in cancer among workers exposed to dimethyl sulfate, and the second study lacked adequate exposure information. Tumors have been observed in the nasal passages, lungs, and thorax of animals exposed to dimethyl sulfate by inhalation. EPA has classified dimethyl sulfate as a Group B2, probable human carcinogen.
Dimethyl sulfate is a colorless, oily liquid that is slightly soluble in water.
Dimethyl sulfate is used as a methylating agent in the manufacture of many organic chemicals. It is also used in the manufacture of dyes and perfumes, for the separation of mineral oils, and for the analysis of auto fluids. Formerly, dimethyl sulfate was used as a war gas. U.S. Department of Health and Human Services. National Library of Medicine, National Toxicology Information Program, Bethesda, MD. 1993.