Malathion

8 hr Time Weighted Avg (TWA): 1 mg/cu m, skin, Inhalable fraction and vapor

Peak Exposure Recommendation: Transient increases in workers' exposure levels may exceed 3 times the value of the TLV-TWA level for no more than 15 minutes at a time, on no more than 4 occasions spaced 1 hour apart during a workday, and under no circumstances should they exceed 5 times the value of the TLV-TWA level. In addition, the 8-hour TWA is not to be exceeded for an 8-hour work period.

Biological Exposure Index (BEI): Determinant: cholinesterase activity in red blood cells; Sampling Time: discretionary; BEI: 70% of individual's baseline. The determinant is nonspecific, since it is also observed after exposure to other chemicals. /Acetylcholinesterase inhibiting pesticides/

A4; Not classifiable as a human carcinogen.