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

CAS number: 121–44–8

NIOSH REL: The 1989 OSHA PEL may not be protective to workers.

Current OSHA PEL: 25 ppm (100 mg/m3) TWA

1989 OSHA PEL: 10 ppm (40 mg/m3) TWA, 15 ppm (60 mg/m3) STEL

1993-1994 ACGIH TLV: 5 ppm (12 mg/m3) TWA, 15 ppm (36 mg/m3) STEL

Description of substance: Colorless liquid with a strong, ammonia-like odor.

LEL: . . 1.2% (10% LEL, 1,200 ppm)

Original (SCP) IDLH: 1,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the UCC [1970] report that a 4-hour exposure to 1,000 ppm killed 1 of 6 rats.

Short-term exposure guidelines: None developed


Lethal concentration data:

Species Reference LC50




Time Adjusted 0.5-hr


Derived value
G. pig



Carpenter et al. 1948

Izmerov et al. 1982

Smyth et al. 1951

LC33: 1,000


LC17: 1,000




4 hr

2 hr

4 hr

2,000 ppm (2.0)

2,280 ppm (1.6)

2,000 ppm (2.0)

200 ppm

228 ppm

200 ppm

Other animal data: RD50 (mouse), 184 ppm [Nielsen and Yamagiwa 1989].

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

Revised IDLH: 200 ppm

Basis for revised IDLH: The revised IDLH for triethylamine is 200 ppm based on acute inhalation toxicity data in animals [Carpenter et al. 1948; Izmerov et al. 1982; Nielsen and Yamagiwa 1989; Smyth et al. 1951]. This may be a conservative value due to the lack of acute inhalation toxicity data for workers.


1. Carpenter CP, Smyth HF Jr, Shaffer CB [1948]. The acute toxicity of ethylene imine to small animals. J Ind Hyg Toxicol 30:2-6.

2. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 115.

3. Nielsen GD, Yamagiwa M [1989]. Structure-activity relationships of airway irritating aliphatic amines. Receptor activation mechanisms and predicted industrial exposure limits. Chem Biol Interact 71(2-3):223-244.

4. Smyth HF Jr, Carpenter CP, Weil CS [1951]. Range-finding toxicity data: list IV. AMA Arch Ind Hyg Occup Med 4:119-122.

5. UCC [1970]. Toxicology studies: triethylamine. New York, NY: Union Carbide Corporation.