Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 126–99–8
NIOSH REL: 1 ppm (3.6 mg/m3) 15-minute CEILING; NIOSH considers ß-chloroprene 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 [skin]
1989 OSHA PEL: 10 ppm (35 mg/m3) TWA [skin]
1993-1994 ACGIH TLV: 10 ppm (36 mg/m3) TWA [skin]
Description of Substance: Colorless liquid with a pungent, ether-like odor.
LEL: . . 4.0% (10% LEL, 4,000 ppm)
Original (SCP) IDLH: 400 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty  that no mice died from a 1-hour exposure to 277 ppm, but all mice died from a 1-hour exposure to 829.2 ppm [von Oettingen et al. 1936].
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|
|Izmerov et al. 1982von Oettingen et al. 1936
von Oettingen et al. 1936
von Oettingen et al. 1936
|4 hr1 hr
|6,414 ppm (2.0)1,036 ppm (1.25)
2,629 ppm (2.5)
876 ppm (2.5)
|641 ppm104 ppm
Human data: Exposure to 973 ppm has resulted in nausea and giddiness in volunteers in 10 to 15 minutes [Nystrom 1948]. Extreme fatigue and unbearable chest pain has occurred following a month of exposure to concentrations ranging from 56 to 334 ppm [Nystrom 1948].
|Revised IDLH: 300 ppmBasis for revised IDLH: The revised IDLH for ß-chloroprene is 300 ppm based on acute inhalation toxicity data in humans [Nystrom 1948]. [Note: NIOSH recommends as part of its carcinogen policy that the “most protective” respirators be worn for ß-chloroprene at concentrations above 1 ppm.]|
1. Izmerov NF, Sanotsky IV, Sidorov KK . Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 38.
2. Nystrom AE . Health hazards in the chloroprene rubber industry and their prevention. A clinical and experimental study, with special reference to chloroprene and its oxidation and polymerization products. Acta Med Scand 123 (Suppl 219):5-125.
3. Patty FA, ed. . Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1320.
4. von Oettingen WF, Hueper WC, Deichmann-Grubler W, Wiley FH . 2-Chlorobutadiene (chloroprene): its toxicity and pathology and the mechanism of its action. J Ind Hyg Toxicol 18 (4):247-249.
- Page last reviewed: December 4, 2014
- Page last updated: December 4, 2014
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