OSHA comments from the January 19, 1989 Final Rule on Air Contaminants Project extracted from 54FR2332 et. seq. This rule was remanded by the U.S. Circuit Court of Appeals and the limits are not currently in force.
CAS: 148-01-6; Chemical Formula: C8H7N3O5
OSHA previously had no limit for dinitolmide. The proposed 8-hour TWA PEL was 5 mg/m3, and the final rule adopts this limit. NIOSH (Ex. 8-47, Table N1) agreed with the selection of this PEL. The ACGIH has an 8-hour limit of 5 mg/m3 TWA for this yellowish solid.
In rats, the oral LD(50) for males is 560 mg/kg, and for females, 650 mg/kg; the ACGIH (1986/Ex. 1-3, p. 213) concludes that dinitolmide has moderate oral toxicity in rats. Two-year dietary studies of rats fed 62.5 ppm (or 3 mg/kg/day) dinitolmide reported no ill effects. Rats of both sexes fed 6 mg/kg/day showed slight fatty changes in the liver; female rats also exhibited slight liver weight increases. Dogs fed 10 mg/kg/day showed no effects after one year. A three-generational study of rats fed 3 or 6 mg/kg/day revealed no effects on fertility, gestation, viability, or lactation (Dow Chemical Company 1973e, as cited in ACGIH 1986/Ex. 1-3, p. 213). There are no inhalation data for dinitolmide.
OSHA is establishing an 8-hour TWA PEL for dinitolmide of 5mg/m3. The Agency concludes that this limit will protect workers from the significant risk of material impairment in the form of the hepatic changes that are potentially associated with exposure to this substance at levels above the new PEL.