Ethylene oxide is a raw material used as a base substance for the production of important derivatives, including di-, tri-, and poly(ethylene) glycols, cellulose and poly(propylene) glycol, ethylene glycol ethers, ethanol-amines, fatty alcohol products and fatty amines, and alkyl phenols. A very small part of the production of ethylene oxide is used directly in gaseous form as a sterilization agent, fumigant, and insecticide (alone or in a mixture with nitrogen, carbon dioxide, or dichlorofluoromethane). Ethylene oxide is used to sterilize drugs, hospital equipment, disposable and reusable medical items, packaging materials, food, books, museum objects, scientific equipment, clothing, furs, wagons, airplanes, and beehives. Additional nonoccupational sources of ethylene oxide exposure are tobacco, residues in spices, and skin care products, in very small amounts. Ethylene oxide is produced during the burning of fossil fuel. There is a causal relationship between exposure to ethylene oxide and the occurrence of lymphatic and hematopoietic cancers (non-Hodgkin’s lymphoma, multiple myeloma, and chronic lymphocytic leukemia) and breast cancer. Its urinary carcinogen indicators are S-(2-hydroxyethyl)glutathione and N-acetyl-S-(2-hydroxyethyl)-L-cysteine ​​(hydroxyethyl mercapturic acid [HEMA])—conjugates with glutathione, as well as ethylene glycol.