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

CAS number: 121–69–7

NIOSH REL: 5 ppm (25 mg/m3) TWA, 10 ppm (50 mg/m3) STEL [skin]

Current OSHA PEL: 5 ppm (25 mg/m3) TWA [skin]

1989 OSHA PEL: 5 ppm (25 mg/m3) TWA, 10 ppm (50 mg/m3) STEL [skin]

1993-1994 ACGIH TLV: 5 ppm (25 mg/m3) TWA, 10 ppm (50 mg/m3) STEL [skin]

Description of Substance: Pale yellow, oily liquid with an amine-like odor.

LEL:. . Unknown

Original (SCP) IDLH: 100 ppm

Basis for original (SCP) IDLH: No quantitative data on acute inhalation toxicity are available for dimethylaniline. Because the TLV for dimethylaniline is based on an analogy with aniline [ACGIH 1971], the chosen IDLH is also based on an analogy with aniline, which has an IDLH of 100 ppm.

Short-term exposure guidelines: None developed


Lethal concentration data:






Adjusted 0.5-hr




Rat Slusar et al. 1972 ----- 50 4 hr 100 ppm (2.0) 10 ppm

Lethal dose data:







Adjusted LD

Derived value
Rat Smyth et al. 1962 oral 1,410 ----- 1,958 ppm 196 ppm

Human data: N,N-Dimethylaniline has been reported to be quantitatively less toxic than aniline but produces a very similar effect -- notably, methemoglobinemia [Clayton and Clayton 1981]. It has been reported that 50 mg/kg is the lethal oral dose [Hall 1969]. [Note: An oral dose of 50 mg/kg is equivalent to a 70-kg worker being exposed to 2,333 mg/m3 (463 ppm) for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]

Revised IDLH: 100 ppm [Unchanged]

Basis for revised IDLH: Based on an analogy with aniline [Clayton and Clayton 1981] which has an IDLH of 100 ppm and to acute oral toxicity data in humans [Hall 1969], the original IDLH for N,N-dimethylaniline (100 ppm) is not being revised for at this time.


1. ACGIH [1971]. Dimethylaniline (n-dimethylaniline). In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 89.

2. Clayton GD, Clayton FE, eds. [1981]. Patty's industrial hygiene and toxicology. 3rd rev. ed. Vol. 2A. Toxicology. New York: John Wiley & Sons, Inc., pp. 2416-2454.

3. Hall R [1969]. Adhesives. Washington DC: National Clearinghouse for Poison Control Centers Bulletin, p. 5. Jan/Feb, 1969.

4. Slusar MP, Zvezday VI, Kolodub FA [1972]. Hygienic standardization of N,N-dimethylaniline in the air of industrial premises. Gig Sanit 37(4):35-37 (in Russian).

5. Smyth HF, Carpenter CP, Weil CS, Pozzani UC, Striegel JA [1962]. Range-finding toxicity data: list VI. Am Ind Hyg Assoc J 23:95-107.