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Monomethyl aniline

May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)

CAS number: 100–61–8

NIOSH REL: 0.5 ppm (2 mg/m3) TWA [skin]

Current OSHA PEL: 2 ppm (9 mg/m3) TWA [skin]

1989 OSHA PEL: 0.5 ppm (2 mg/m3) TWA [skin]

1993-1994 ACGIH TLV: 0.5 ppm (2.2 mg/m3) TWA [skin]

Description of substance: Yellow to light-brown liquid with a weak, ammonia-like odor.

LEL: . . . Unknown

Original (SCP) IDLH: 100 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on an analogy with aniline which has an IDLH of 100 ppm.

Short-term exposure guidelines: None developed


Lethal dose data:

Species Reference Route LD50 (mg/kg) LDLo (mg/kg) Adjusted LD Derived value
RabbitG. pig Treon et al. 1949von Oettingen 1941 oraloral ———- 2801,200 439 ppm1,883 ppm 44 ppm188 ppm

Other animal data: It has been reported that a dog survived 50 seven-hour exposures to 86 ppm [Treon et al. 1949].

Human data: None relevant for use in determining the revised IDLH.


1. Treon JF, Deichmann WB, Sigmon HE, Wright H, Witherup SO, Heyroth FF, Kitzmiller KV, Keenan C [1949]. The toxic properties of xylidine and monomethylaniline. I. The comparative toxicity of xylidine and monomethylaniline when administered orally or intravenously to animals or applied on their skin. J Ind Hyg Toxicol 31:1-20.

2. von Oettingen WF [1941]. The aromatic amino and nitro compounds, their toxicity and potential dangers. Public Health Bulletin 271:16.