Document KGb3kaX30gBkry3eR91zXvdbr

POTENTIAL HEALTH EFFECTS Health & Environmental Sciences T.I.M.E. SYSTEM DR-0001-5849 METHYLENE CHLORIDE PAGE 2 01/19/93 rept h riCUTE INHALATION EFFECTS - In confined or poorly ventilated areas, vapors can readily accumulate and can cause unconsciousness and death. - Excessive exposure may cause irritation to upper respiratory tract. - Excessive exposure may cause carboxyhemoglobi-nemia, thereby impairing the blood's ability to transport oxygen. - Minimal anesthetic or narcotic effects may be seen in the range of 500-1000 ppm methylene chloride. Progressively higher levels over 1000 ppm can cause dizziness, drunkenness, and as low as 10,000 ppm, unconsciousness and death. - These high levels may also cause cardiac arrhythmias (irregular heartbeats). SUBCHRONIC EFFECTS - Signs and symptoms of excessive exposure may be central nervous system effects. - Excessive exposure may cause carboxyhemoglobinemia, thereby impairing the blood's ability to transport oxygen. - Observations in animals include liver and kidney effects. CHRONIC EFFECTS / CARCINOGENICITY - For hazard communication purposes under OSHA Standard 29 CFR Part 1910.1200, this chemical is listed as a potential carcinogen by IARC and NTP. - Methylene chloride has been shown to increase the rate of spontaneously ^ occurring malignant tumors in the B6C3F1 mouse and benign tumors in laboratory rats. - Other animal studies, as well as several human epidemiology studies, failed to show a tumorigenic response. Methylene chloride is not believed to pose a measurable carcinogenic risk to man when handled as recommended. TERATOGENIC EFFECTS - Birth defects are unlikely. Exposures having no effect on the mother should have no effect on the fetus. Did not cause birth defects in animals; other effects were seen in the fetus only at doses which caused toxic effects to the mother. REPRODUCTIVE EFFECTS - In animal studies, has been shown not to interfere with reproduction. MUTAGENICITY - Negative or equivocal results have been obtained in mutagenicity tests with methylene chloride using mammalian cells or animals. This is . consistent with the lack of interaction with DNA in rats and hamsters. - Although results of Ames bacterial tests have generally been positive, overall the data suggest that genotoxic potential does not appear to be a significant factor in the toxicity of methylene chloride. * TRADEMARK OF THE DOW CHEMICAL COMPANY RESTRICTED - DOW USE ONLY DO A 019503 CONFIDENTIAL