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

CAS number: 118–96–7

NIOSH REL: 0.5 mg/m3 TWA [skin]

Current OSHA PEL: 1.5 mg/m3 TWA [skin]

1989 OSHA PEL: 0.5 mg/m3 TWA [skin]

1993-1994 ACGIH TLV: 0.5 mg/m3 TWA [skin]

Description of substance: Colorless to pale-yellow, odorless solid or crushed flakes.

LEL :. . Unknown

Original (SCP) IDLH*: No Evidence [*Note: “Effective” IDLH = 3,000 mg/m3 — see discussion below.]

Basis for original (SCP) IDLH: Most of the data reported in the literature about trinitrotoluene (TNT) poisoning concern the effects caused by chronic exposures. The available toxicological data contain no evidence that an acute exposure to a high concentration of TNT would impede escape or cause irreversible health effects within 30 minutes. AIHA [1964] reported that both the short exposure tolerance to TNT and the atmospheric concentration immediately hazardous to life are not important parameters. For this draft technical standard, therefore, respirators have been selected on the basis of the assigned protection factor afforded by each device up to 2,000 ´ the OSHA PEL of 1.5 mg/m3 (i.e., 3,000 mg/m3; only the “most protective” respirators are permitted for use in concentrations exceeding 3,000 mg/m3).

Short-term exposure guidelines: None developed


Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived value



Dilley et al. 1982Dilley et al. 1982

MRC 1921

MRC 1921










5,565 mg/m34,620 mg/m3

3,500 mg/m3

12,950 mg/m3

557 mg/m3462 mg/m3

350 mg/m3

1,295 mg/m3

Human data: The probable lethal dose has been reported to be 2 grams [Deichmann and Gerarde 1969]. [Note: An oral dose of 2 grams is equivalent to a worker being exposed to about 1,300 mg/m3 for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]


1. AIHA [1964]. 2,4,6-Trinitrotoluene (TNT). In: Hygienic guide series. Am Ind Hyg Assoc J 25:516-519.

2. Deichmann WB, Gerarde HW [1969]. Trinitrotoluene (TNT). In: Toxicity of drugs and chemicals. New York, NY: Academic Press, Inc., Inc., p. 610.

3. Dilley JV, Tyson CA, Spanggord RJ, Sasmore DP, Newell GW, Dacre JC [1982]. Short-term oral toxicity of 2,4,6-trinitrotoluene in mice, rats, and dogs. J Toxicol Environ Health 9:565-585.

4. MRC [1921]. Special report series. Medical Research Council, Special Report Series, 58:32.