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General Description

  • Synonyms: 2-Chloro-1,3-butadiene; Chlorobutadiene; Chloroprene
  • OSHA IMIS Code Number: 0680
  • IMIS Name History: Chloroprene prior to 5/30/07
  • Chemical Abstracts Service (CAS) Registry Number: 126-99-8
  • NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: EI9625000
  • Department of Transportation Regulation Number (49 CFR 172.101) and Emergency Response Guidebook: 1991 131P (inhibited)
  • NIOSH Pocket Guide to Chemical Hazards, beta-Chloroprene: chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

  • OSHA Permissible Exposure Limit (PEL):
  • American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 10 ppm, 36 mg/m3 TWA; Skin
  • National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): 1 ppm, 3.6 mg/m3 Ceiling (15 minutes); Appendix A - NIOSH Potential Occupational Carcinogens

Health Factors

  • Carcinogenic Classification:
  • NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 300 ppm
  • Potential Symptoms: Irritation of eyes, skin, respiratory system; cough, sore throat; headache, dizziness, drowsiness, anxiety, irritability; dermatitis, alopecia; reproductive effects; Skin Absorption: redness, pain; [potential occupational carcinogen]
  • Health Effects: Reproductive Hazard (HE5); Systemic Toxicity (HE3); Suspected human carcinogen, mutagen (HE2)
  • Affected Organs: Eyes, skin, respiratory system, reproductive system
  • Notes:
    1. Chloroprene is an OSHA Select Carcinogen.
    2. EPA's inhalation reference concentration (daily inhalational exposure likely to be without an appreciable risk of deleterious effects during a lifetime) for chloroprene is 7 µg/m3, and EPA's provisional reference dose (RfD) for chloroprene is 0.02 mg/kg/day.
    3. Chloroprene is metabolized by cytochrome P-450 2E1 to reactive epoxide intermediates, including enantiomers of (1-chloroethenyl)oxirane, which can form adducts with glutathione, hemoglobin, and DNA. No reports of using any of these adducts as markers for occupational exposure to chloroprene were found.
    4. Anemia has been reported to occur in Fischer 344 rats exposed subchronically to 200 ppm chloroprene, as well as in employees occupationally exposed to unreported levels of chloroprene.
  • Literature Basis:
    • NIOSH Pocket Guide to Chemical Hazards: beta-Chloroprene.
    • International Chemical Safety Cards (WHO/IPCS/ILO): Chloroprene.
    • EPA Technology Transfer Network Air Toxics Website: Chloroprene (2-Chloro-1,3-Butadiene).
    • Hurst, H.E. and Ali, M.Y.: Analyses of (1-chloroethenyl)oxirane headspace and hemoglobin N-valine adducts in erythrocytes indicate selective detoxification of (1-chloroethenyl)oxirane enantiomers. Chem. Biol. Interact. 166(1-3): 332-340, 2007.
    • Munter, T., Cottrell, L., Ghai, R., Golding, B.T. and Watson, W.P.: The metabolism and molecular toxicology of chloroprene. Chem. Biol. Interact. 166(1-3): 323-331, 2007.
    • No Author: Chloroprene (PDF). Report on Carcinogens (latest edition); U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program.
    • Pohanish, R.P. (editor): Chloroprene. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 1. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 591-593.
    • Sanotskii, I.V.: Aspects of the toxicology of chloroprene: immediate and long-term effects. Environ. Health Perspect. 17: 85-93, 1976.
    • Valentine, R. and Himmelstein, M.W.: Overview of the acute, subchronic, reproductive, developmental and genetic toxicology of beta-chloroprene. Chem. Biol. Interact. 135-136: 81-100, 2001.
  • Date Last Revised: 08/25/2006

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):
  • Chromosorb 106 (600/300 mg sections, 60/80 mesh)
  • maximum volume: 6 Liters
  • maximum flow rate: 0.05 L/min
  • current analytical method: Gas Chromatography; GC/ECD
  • analytical solvent: Toluene
  • method reference: OSHA Analytical Method (OSHA 112)
  • method classification: Fully Validated
Wipe Sampling Method:
  • charcoal pad
  • note: Seal in glass vial for shipment.

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