beta-Chloroprene

Agent Name
beta-Chloroprene
Alternative Name
2-Chloro-1,3-butadiene
CAS Number
126-99-8
Formula
C4-H5-Cl
Major Category
Plastics & Rubber
beta-Chloroprene formula graphical representation
Synonyms
Chlorobutadiene; Chloroprene; 2-Chloro-1,3-butadiene; [NIOSH] UN1991;
Category
Other Monomers
Description
Colorless liquid with a pungent, ether-like odor; [NIOSH]
Sources/Uses
Used to manufacture synthetic rubber (neoprene and polychloroprene latex); [ACGIH]
Comments
Chloroprene was toxic to workers at 80 ppm and dangerous at 200 ppm causing respiratory irritation and respiratory depression. Acute animal studies show evidence of liver injury. TLV Basis is lung cancer, upper respiratory tract irritation, and eye irritation. A 2-year rodent bioassay found lung cancer as the most frequently occurring neoplastic lesion. A cohort of 5000 workers exposed to a mean concentration of 5.23 ppm for a median of 18 years had no increased deaths from lung cancer or other cancers over a 60-year follow-up. [ACGIH] A lachrymator; [HSDB] Can cause chemical burns; [NIOSH Guidelines for Chemical Hazards] In high-dose reproductive studies of animals, chloroprene or its metabolites can cause testicular damage. Increased spontaneous abortions were measured in one population study of exposed workers. [Frazier, p. 338-9] Chloroprene (UN1991) has warning of explosive polymerization; [ERG 2016]
Biomedical References

Exposure Assessment

Skin Designation (ACGIH)
Yes
TLV (ACGIH)
1 ppm
PEL (OSHA)
25 ppm
IDLH (NIOSH)
300 ppm
Excerpts from Documentation for IDLHs
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].
Vapor Pressure
215 mm Hg
Odor Threshold Low
0.11 ppm
Odor Threshold High
138 ppm
Lethal Concentration
LC50 (rat) = 3,270 ppm/4 hr
Explosive Polymerization
Yes
Explanatory Notes
Odor threshold from AIHA; Flash point = -4 deg F; [CHEMINFO] VP from HSDB;
Half Life
No reports found; [TDR, p. 334]
NFPA
may ignite at ambient temp

Adverse Effects

Lachrymator
Yes
Neurotoxin
Other CNS neurotoxin
Hepatotoxin
Hepatoxic (a) from occupational exposure (secondary effect) or (b) in animal studies or in humans after ingestion
Reproductive Toxin
Yes
Dermatotoxin
Skin burns
IARC Carcinogen
Possible (2b)
NTP Carcinogen
Anticipated human carcinogen
ACGIH Carcinogen
Suspected Human

Diseases, Processes, and Activities Linked to This Agent

Diseases

Occupational diseases associated with exposure to this agent: