Dichloromethane is used extensively in commercial and industrial solvent applications. The background atmospheric concentration is about 35 ppt. In surface water and drinking water, measured concentrations generally have been in the low parts per billion range. Available data suggest that DCM is biodegradable and has low aquatic toxicity to aquatic organisms. The weight of evidence from the available literature indicates that adverse toxicologic (non-genotoxic) effects in humans are unlikely to occur at ambient air or water levels found or expected in the general environment. Available evidence suggests that the teratogenic potential of DCM for humans is minimal. The weight of evidence with respect to mutagenic potential shows that DCM is capable of causing gene mutations and has the potential to cause such effects in exposed human cells. With regard to cancer, the weight of evidence from experimental animal studies is limited. When the absence of epidemiological evidence is considered with the limited animal evidence, the overall evaluation of DCM using the criteria of the International Agency for Research on Cancer is a Group 3 chemical in that it cannot be classified as to its carcinogenic potential for humans.

Distributed to depository libraries in microfiche. "February 1985." Includes bibliographical references. "EPA 600-8-82-004 F." Cover title.