May 1994

Documentation for Immediately Dangerous To Life or Health Concentrations (IDLHs)

Dimethylamine

CAS number: 124–40–3

NIOSH REL: 10 ppm (18 mg/m³) TWA

Current OSHA PEL: 10 ppm (18 mg/m³) TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 5 ppm (9.2 mg/m³) TWA, 15 ppm (27.6 mg/m³) STEL

Description of Substance: Colorless gas with an ammonia- or fish-like odor.

LEL:. . 2.8% (10% LEL, 2,800 ppm)

Original (SCP) IDLH: 2,000 ppm

Basis for original (SCP) IDLH: No data on acute inhalation toxicity are available for dimethylamine. Therefore, the chosen IDLH is based on an analogy with diethylamine which has an IDLH of 2,000 ppm.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA

Lethal concentration data:

Species

Reference

LC₅₀

(ppm)

LC_Lo

(ppm)

Time

Adjusted 0.5-hr

LC (CF)

Derived

value

Rat

Mouse

Koch et al. 1980

Steinhagen et al. 1982

4,700

4,540

7,650

-----

4 hr

6 hr

2 hr

9,400 ppm (2.0)

10,442 ppm (2.3)

12,240 ppm (1.6)

940 ppm

1,044 ppm

1,224 ppm

Lethal dose data:

Species

Reference

Route

LD₅₀

(mg/kg)

LD_Lo

(mg/kg)

Adjusted LD

Derived value

Rat

Mouse

Rabbit

G. pig

Dzhanashvili 1967

oral

698

316

240

-----

2,613 ppm

1,183 ppm

898 ppm

261 ppm

118 ppm

90 ppm

Other animal data: RD₅₀ (mouse), 511 ppm [Steinhagen et al. 1982]; RD₅₀ (rat), 573 ppm [Steinhagen et al. 1982].

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

Revised IDLH: 500 ppm

Basis for revised IDLH: The revised IDLH for dimethylamine is 500 ppm based on acute inhalation toxicity data in animals [Steinhagen et al. 1982].

REFERENCES:

1. Dzhanashvili GD [1967]. Maximum permissible concentration of dimethylamine in water bodies. Gig Sanit 32(6):329-335 (translated).

2. Koch F, Guenter M, Kliche R, Lang R [1980]. Studies on the aerogenic intoxication of rats by means of methylamines. Wiss Z: Karl Marx University, Leipzig, Math-Naturwiss. Reihe 29:463-474. [From ACGIH [1991]. Dimethylamine. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 479-481.]

3. Steinhagen WH, Swenberg JA, Barrow CS [1982]. Acute inhalation toxicity and sensory irritation of dimethylamine. Am Ind Hyg Assoc J 43(6):411-417.