Dimethyl Sulfate is an odorless, corrosive, oily liquid with an onion-like odor that emits toxic fumes upon heating. Dimethyl sulfate is used in industry as a methylating agent in the manufacture of many organic chemicals. Inhalation exposure to its vapors is highly irritating to the eyes and lungs and may cause damage to the liver, kidney, heart and central nervous system, while dermal contact causes severe blistering. It is a possible mutagen and is reasonably anticipated to be a human carcinogen based on evidence of carcinogenicity in experimental animals. Exposure to dimethyl sulfate is primarily occupational. Acute (short-term) exposure of humans to the vapors of dimethyl sulfate may cause severe inflammation and necrosis of the eyes, mouth, and respiratory tract. Acute oral or inhalation exposure to dimethyl sulfate primarily damages the lungs but also injures the liver, kidneys, heart, and central nervous system (CNS), while dermal contact with dimethyl sulfate may produce severe blistering in humans. Human data on the carcinogenic effects of dimethyl sulfate are inadequate. 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.