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

G. pig

Treon et al. 1949

von Oettingen 1941







439 ppm

1,883 ppm

44 ppm

188 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.

Revised IDLH: 100 ppm [Unchanged]

Basis for revised IDLH: Based on animal subchronic inhalation toxicity data [Treon et al. 1949] and an analogy to aniline which has a revised IDLH of 100 ppm, the original IDLH for monomethyl aniline (100 ppm) is not being revised at this time.


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.

Page last reviewed: December 4, 2014