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n-Heptane

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

CAS number: 142–82–5

NIOSH REL: 85 ppm (350 mg/m3) TWA,

440 ppm (1,800 mg/m3) 15-minute CEILING

Current OSHA PEL: 500 ppm (2,000 mg/m3) TWA

1989 OSHA PEL 400 ppm (1600 mg/m3) TWA, 500 ppm (2,000 mg/m3) STEL

1993-1994 ACGIH TLV: 400 ppm (1,640 mg/m3) TWA, 500 ppm (2,050 mg/m3) STEL

Description of Substance: Colorless liquid with a gasoline-like odor.

LEL:. . 1.05% (10% LEL, 1,050 ppm)

Original (SCP) IDLH: 5,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] that a 15-minute exposure to 5,000 ppm produced a state of intoxication characterized by uncontrolled hilarity in some individuals and in others a stupor lasting for 30 minutes after the exposure [Patty and Yant 1929]. According to Patty [1963], a 4-minute exposure to this same concentration produces vertigo and incoordination [Patty and Yant 1929]. These symptoms described by Patty [1963] could perhaps impede escape.

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA

Lethal concentration data:

Species Reference LC50(ppm) LCLo(ppm) Time Adjusted 0.5-hrLC (CF) Derivedvalue
HumanMouse

Mouse

 Flury and Zernik 1931Marhold 1986

Swann et al. 1974

 —–17,986

—–

 16,000—–

15,000

 ?2 hr

30 min

 ?28,778 ppm (1.6)

15,000 ppm (1.0)

 ?2,878 ppm

1,500 ppm

 

Other human data: Inhalation of 1,000 ppm for 6 minutes was associated with slight dizziness [Patty and Yant 1929]. Exposure to 5,000 ppm for 4 minutes produced complaints of nausea, a loss of appetite, vertigo, and incoordination [Patty and Yant 1929]. A 15-minute exposure to 5,000 ppm produced a state of intoxication characterized by uncontrolled hilarity in some individuals and in others a stupor lasting for 30 minutes after the exposure [Patty and Yant 1929].

 

REFERENCES:

1. Flury F, Zernik F [1931]. Schädliche gase dämpfe, nebel, rauch- und staubarten. Berlin, Germany: Verlag von Julius Springer, pp. 257-264 (in German).

2. Marhold J [1986]. Prehled Prumyslove Toxikologie, Organicke Latky. Prague, Czechoslovakia: Avicenum, p. 9 (in Czechoslovakian).

3. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., pp. 1198-1199.

4. Patty FA, Yant WP [1929]. Odor intensity and symptoms produced by commercial propane, butane, pentane, hexane, and heptane vapor. Pittsburgh, PA: Department of Commerce, U.S. Bureau of Mines, Report of Investigations, No. 2979, pp. 1-10.

5. Swann HE Jr, Kwon BK, Hogan GK, Snellings WM [1974]. Acute inhalation toxicity of volatile hydrocarbons. Am Ind Hyg Assoc J 35:511-518.