Methylene chloride is used as a solvent, especially where high volatility is required. It is a good solvent for oils, fats, waxes, resins, bitumen, rubber and cellulose acetate and is a useful paint stripper and degreaser. It is used in paint removers, in propellant mixtures for aerosol containers, as a solvent for plastics, as a degreasing agent, as an extracting agent in the pharmaceutical industry, and as a blowing agent in polyurethane foams. Its solvent property is sometimes increased by mixing with methanol, petroleum naphtha, or tetrachloroethylene. The Occupational Safety and Health Administration (OSHA) estimates that approximately 35,000 workers are exposed to methylene chloride.

Studies indicate that there is suggestive, but not absolute evidence that methylene chloride is a human carcinogen. Long-term respiratory exposure in excess of 25 parts per million (ppm) is reported to be associated with an increased risk of cancer of the bile duct and brain.

Short term (acute) airborne exposures to high concentrations more than 125 ppm may cause mental confusion, light-headedness, nausea, vomiting, and headache. Continued exposure may also cause eye and respiratory tract irritation. Exposure to methylene chloride may make symptoms of angina (chest pain) worse. Skin exposure to liquid methylene chloride may cause irritation. Liquid methylene chloride placed on the skin may cause chemical burns.

Activities where exposure to methylene chloride is possible is in using paint strippers, working in laboratories, and parts degreasing. These areas should be initially and periodically assessed for exposures.

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