Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 90-04-0
NIOSH REL: 0.5 mg/m3 TWA [skin]; NIOSH considers o-anisidine to be a potential occupational carcinogen as defined by the OSHA carcinogen policy [29 CFR 1990].
Current OSHA PEL: 0.5 mg/m3 TWA [skin]
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 0.1 ppm (0.5 mg/m3) TWA [skin]
Description of substance: Red or yellow, oily liquid with an amine-like odor.
Original (SCP) IDLH: 50 mg/m3
Basis for original (SCP) IDLH: Because no data on acute inhalation toxicity are available for anisidine (o-, p-isomers), the chosen IDLH is based on chronic data. ACGIH  reported that mice survived exposures to 10 to 30 mg/m3 for 2 hours/day, 6 days/week for 1 month; a decrease in the excitability of nerves was noted [Zaeva and Fedorova 1962]. Because mice survived 30 mg/m3, 2 hours/day, 6 days/week for 1 month, a worker should be able to escape from 50 mg/m3 without injury or irreversible health effects.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal dose data:
|Species||Reference||Route||LD50(mg/kg)||LDLo(mg/kg)||Adjusted LD||Derived Value|
|Rat||IARC 1982||oral||2,000||—–||14,000 mg/m3||1,400 mg/m3|
|Mouse||IARC 1982||oral||1,400||—–||9,800 mg/m3||980 mg/m3|
|Rabbit||IARC 1982||oral||870||—–||6,090 mg/m3||609 mg/m3|
Other animal data: Mice have survived exposures to concentrations of 10 to 30 mg/m3 for 2 hours/day, 6 days/week for 1 month with only a decrease in the excitability of nerves noted [Zaeva and Fedorova 1962].
Human data: None relevant for use in determining the revised IDLH.
Revised IDLH: 50 mg/m3 [Unchanged]
Basis for revised IDLH: Based on subchronic inhalation toxicity data in animals [Zaeva and Fedorova 1962], the original IDLH for o-anisidine (50 mg/m3) is not being revised at this time. [Note: NIOSH recommends as part of its carcinogen policy that the “most protective” respirators be worn for o-anisidine at concentrations above 0.5 mg/m3.]
- ACGIH . Anisidine (o-, p-isomers). In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 14.
- IARC . IARC monographs on the evaluation of carcinogenic risk of chemicals to humans. Vol. 27. Lyon, France: World Health Organization, International Agency for Research on Cancer, p. 63.
- Zaeva GN, Fedorova VI . Toxsikol Nov Prom Khim Vesh 4:91 (in Russian).