LP 1005 A

SECTION 2: Hazards identification

29 CFR 1910.1200) This material is classified as hazardous under

Medical Conditions Generally Aggravated by Exposure

Overexposure Preexisting conditions such as asthma, allergies, eczema, bronchitis, and other lung and skin disorders may be aggravated by exposure to the product. Results from a lifetime inhalation study in rats indicate that MDI aerosol was carcinogenic at 9 mg/m3, the highest dose tested. This is well above the recommended TLV of 5ppb (0.05 mg/m3). Only irritation was noted at the lower concentration of 0.2 and 1 mg/m3. No birth defects or teratogenic effects were reported in a teratology study with rats exposed to 1, 4, and 12 mg/m3 polymeric MDI for 6 hr/day on days 6-15 of gestation. Embryotoxicity and fetotoxicity was reported at the top dose in the presence of maternal toxicity. As a result of previous repeated overexposures or a single large dose, certain individuals will develop isocyanate sensitization (chemical asthma), which will cause them to react to a later exposure to isocyanate at levels well below the PEL/TVL. Those symptoms, which include chest tightness, wheezing, cough, shortness of breath, or asthmatic attack, could be immediate of delayed up to several hours after exposure. Similar to many non-specific asthmatic Individuals who are sensitized to isocyanates and those with preexisting lung diseases of conditions, including non- specific bronchial hyper reactivity or asthma, must avoid all exposure to isocyanates.

Response

there are reports that once sensitized an individual can experience these symptoms upon exposure to dust, cold air or other irritants. This increased lung sensitivity can persist for weeks and in severe cases for several years. Chronic overexposure to isocyanates has also been reported to cause lung damage, including a decrease in lung function, which may be permanent. Sensitization may e either temporary of permanent. Prolonged contact can cause reddening, swelling, rash, scaling, or blistering, in those who have developed a skin sensitization, these symptoms can develop as a result of contact with very small amount s of liquid material, or even as a result of vapor-only exposure. 2

Signal word

Danger

Hazard statements

Harmful if inhaled. Causes skin and eye irritation May Cause allergy or asthma symptoms or breathing difficulties if inhaled. May cause an allergic skin reaction. May cause respiratory irritation.