May 1994

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

2-Nitropropane

CAS number: 79–46–9

NIOSH REL: None established; NIOSH considers 2-nitropropane to be a potential occupational carcinogen as defined by the OSHA carcinogen policy [29 CFR 1990].

Current OSHA PEL: 25 ppm (90 mg/m³) TWA

1989 OSHA PEL: 10 ppm (35 mg/m³) TWA

1993-1994 ACGIH TLV: 10 ppm (36 mg/m³) TWA, A2

Description of substance: Colorless liquid with a pleasant, fruity odor.

LEL: . . 2.6% (10% LEL, 2,600 ppm)

Original (SCP) IDLH: 2,300 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] that the lowest lethal concentration for the cat for a 1-hour exposure was found to be 2,353 ppm; the response of different species to 2-nitropropane varies considerably, but the cat was the most sensitive species in this investigation [Treon and Dutra 1952].

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

Mouse

Rat

Cat

Rabbit

G. pig

Cat

Izmerov et al. 1982

Lewis et al. 1979

Treon & Dutra 1952

2,703

400

-----

714

2,381

4,622

2,353

2 hr

6 hr

5 hr

1 hr

4,324 ppm (1.6)

920 ppm (2.3)

1,535 ppm (2.15)

5,119 ppm (2.15)

9,937 ppm (2.15)

2,941 ppm (1.25)

432 ppm

92 ppm

154 ppm

512 ppm

994 ppm

294 ppm

Human data: Nausea, vomiting, diarrhea, anorexia, and severe headache have been reported in workers exposed to daily concentrations of 20 to 45 ppm [Skinner 1947].

Revised IDLH: 100 ppm

Basis for revised IDLH: The revised IDLH for 2-nitropropane is 100 ppm based on acute inhalation toxicity data in animals [Lewis et al. 1979]. This may be a conservative value due to the lack of relevant acute toxicity data for workers exposed to concentrations above 45 ppm. [Note: NIOSH recommends as part of its carcinogen policy that the "most protective" respirators be worn for 2-nitropropane at any detectable concentration.]

REFERENCES:

1. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 94.

2. Lewis TR, Ulrich CE, Busey WM [1979]. Subchronic inhalation toxicity of nitromethane and 2-nitropropane in rats. J Environ Pathol Toxicol 2(5):233-249.

3. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., pp. 2077-2078.

4. Skinner JB [1947]. The toxicity of 2-nitropropane. Ind Med 16(9):441-443.

5. Treon JF, Dutra FR [1952]. Physiological response of experimental animals to the vapor of 2-nitropropane. AMA Arch Ind Hyg Occup Med 5:52-61.