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1,3-Butadiene, 2-chloro-

RTECS #
EI9625000
CAS #
126-99-8
See: NMAM or OSHA Methods
Updated
March 2018
Molecular Weight
88.54
Molecular Formula
C4H5Cl
Synonyms
2-Chloor-1,3-butadieen (Dutch)
2-Chlor-1,3-butadien (German)
2-Chloro-1,3-butadiene
2-Chloro-1,3-butadiene (OSHA)
2-Chlorobuta-1,3-diene
2-Cloro-1,3-butadiene (Italian)
beta-Chloroprene
beta-Chloroprene (ACGIH:OSHA)
Chlorobutadiene
Chloropreen (Dutch)
Chloropren (German, Polish)
Chloroprene
Cloroprene (Italian)

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
skin /rabbit 500 µL/24H severeNTIS** OTS0535986

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic Analysisunreported route/human1 mg/m3MUREAV 147,301,1985
Cytogenetic Analysisinhalation/rat1960 µg/m3/16WBZARAZ 27(6),102,1974
Cytogenetic Analysisinhalation/mouse320 µg/m3/4W-continuousGTPZAB 20(3),31,1976
DNA Damageinhalation/mouse32 ppm/104W- intermittentCBINA8 135-136,373,2001
Dominant Lethal Testinhalation/rat4 µg/L/48D- intermittentTNICS* 13,56,1973
host-mediated assaySalmonella typhimurium/mouse375 mg/kg/4HZKMAAX 16,41,1976
micronucleus testinhalation/mouse1480 µg/m3/2H/2D-continuousHYDXET 17,209,1986
morphological transformembryo/hamster125 mg/LAETODY 1,241,1980
mutation in microorganisms/Salmonella typhimurium70 µmol/L (+enzymatic activation step)NATUAS 255,641,1975
mutation in microorganisms/Salmonella typhimurium2 pph/4H (-enzymatic activation step)ARTODN 41,249,1979
sex chromosome loss and nondisjunctionoral/Drosophila melanogaster5700 µmol/L/3D- intermittent35WYAM -,63,1976

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
inhalation/rat 4 mg/m3/24H (3-4D pregnant)Reproductive: Effects on embryo or fetus: Fetal deathGTPZAB 19(3),30,1975
inhalation/rat 4 mg/m3/24H (11-12D pregnant)Reproductive: Specific developmental abnormalities: Central nervous systemGTPZAB 19(3),30,1975
inhalation/rat 10 ppm/4H (3-20D pregnant)Reproductive: Effects on fertility: Post- implantation mortality (e.g., dead and/or resorbed implants per total number of implants)TXAPA9 44,81,1978
inhalation/rat 150 µg/m3/24H (19W male)Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)EVHPAZ 17,85,1976
inhalation/rat 500 mg/m3/5H (17W prior to copulation)Reproductive: Maternal effects: Menstrual cycle changes or disordersBEBMAE 60(7),107,1965
inhalation/rat 500 mg/m3/5H (30W prior to copulation)Reproductive: Maternal effects: Ovaries, fallopian tubesBEBMAE 60(7),107,1965
inhalation/rat 0.15 mg/m3 (multigenerations)Reproductive: Effects on embryo or fetus: Fetal deathVCVGH* -,505,1990
inhalation/rat 0.0038 gm/m3 (48D male)Reproductive: Effects on fertility: Pre- implantation mortality (e.g., reduction in number of implants per female; total number of implants per corpora lutea)TPKVAL 13,58,1973
oral/rat 9100 µg/kg (26W male)Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)GISAAA 45(2),17,1980
oral/rat 1 mg/kg (11-12D pregnant)Reproductive: Specific developmental abnormalities: Central nervous systemGTPZAB 19(3),30,1975
oral/rat 1 mg/kg (11-12D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)GTPZAB 19(7),30,1975
oral/rat 1 mg/kg (9-10D pregnant)Reproductive: Other developmental abnormalitiesGTPZAB 19(7),30,1975

Tumorigenic Data and References

Route/OrganismDoseEffectReference
inhalation/mouse lowest published toxic concentration: 32 ppm/6H/2Y- intermittentTumorigenic: Carcinogenic by RTECS criteria

Liver: Tumors

Lung, Thorax, or Respiration: Tumors
NTPTR* NTP-TR-467,1998
inhalation/mouse lowest published toxic concentration: 32 ppm/6H/104W - intermittentTumorigenic: Neoplastic by RTECS criteria

Gastrointestinal: Tumors

Tumorigenic: Increased incidence of tumors in susceptible strains
CBINA8 135-136,373,2001
inhalation/mouse lowest published toxic concentration: 80 ppm/5H/104W - intermittentTumorigenic: Neoplastic by RTECS criteria

Gastrointestinal: Tumors

Tumorigenic: Increased incidence of tumors in susceptible strains
CBINA8 135-136,373,2001
inhalation/mouse lowest published toxic concentration: 791.04 mg/kg/103W- intermittentTumorigenic: Carcinogenic by RTECS criteria

Lung, Thorax, or Respiration: Tumors
NTIS** PB99-123671
inhalation/mouse lowest published toxic concentration: 1977.6 mg/kg/103W- intermittentTumorigenic: Carcinogenic by RTECS criteria

Skin and Appendages: Tumors

Liver: Tumors
NTIS** PB99-123671
inhalation/rat lowest published toxic concentration: 80 ppm/6H/2Y- intermittentTumorigenic: Carcinogenic by RTECS criteria

Olfaction: Tumors
NTPTR* NTP-TR-467,1998
inhalation/rat lowest published toxic concentration: 988.9 mg/kg/103W- intermittentTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Gastrointestinal: Tumors

Kidney, Ureter, and Bladder: Bladder tumors
NTIS** PB99-123671
inhalation/rat lowest published toxic concentration: 2060 mg/kg/103W- intermittentTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Gastrointestinal: Tumors

Endocrine: Thyroid tumors
NTIS** PB99-123671

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/cat Lowest published lethal concentration: 1290 mg/m3/8HJIHTAB 18,240,1936
inhalation/cat Lowest published lethal concentration: 3500 mg/m3/2HVCVGH* -,504,1990
inhalation/human lowest published toxic concentration: 100 mg/kg/5MEye: Lacrimation

Behavioral: Headache

Gastrointestinal: Nausea or vomiting
VCVGH* -,505,1990
inhalation/mouse lethal concentration (50 percent kill): 1600 mg/m3VCVGH* -,504,1990
inhalation/mouse Lowest published lethal concentration: 600 mg/m3/8HVCVGH* -,504,1990
inhalation/mouse lethal concentration (50 percent kill): 2300 mg/m3/2HVCVGH* -,504,1990
inhalation/rabbit Lowest published lethal concentration: 6000 mg/m3/2HVCVGH* -,504,1990
inhalation/rabbit Lowest published lethal concentration: 3870 mg/m3/8HJIHTAB 18,240,1936
inhalation/rat lethal concentration (50 percent kill): 11800 mg/m3/4H85GMAT -,38,1982
inhalation/rat lowest published toxic concentration: 17000 mg/kg/5HLung, Thorax, or Respiration: Acute pulmonary edemaVCVGH* -,504,1990
inhalation/rat lethal concentration (50 percent kill): 300 mg/m3VCVGH* -,504,1990
intravenous/rabbit lowest published lethal dose: 96 mg/kgBlood: Other changes

Skin: After systemic exposure: Dermatitis, other
SBLEA2 44,63,1942
oral/mouse lethal dose (50 percent kill): 146 mg/kg85GMAT -,38,1982
oral/rat lethal dose (50 percent kill): 450 mg/kg85GMAT -,38,1982
subcutaneous/cat lowest published lethal dose: 100 mg/kgJIHTAB 18,240,1936
subcutaneous/mouse lowest published lethal dose: 1 gm/kgBehavioral: Convulsions or effect on seizure threshold

Lung, Thorax, or Respiration: Dyspnea

Lung, Thorax, or Respiration: Cyanosis
JIHTAB 18,240,1936
subcutaneous/pigeon lowest published lethal dose: 13 gm/kgJIHTAB 18,240,1936
subcutaneous/rat lowest published lethal dose: 500 mg/kgBehavioral: Convulsions or effect on seizure threshold

Lung, Thorax, or Respiration: Dyspnea

Lung, Thorax, or Respiration: Cyanosis
JIHTAB 18,240,1936
unreported route/mouse lethal dose (50 percent kill): 146 mg/kgVCVGH* -,504,1990
unreported route/rat lethal dose (50 percent kill): 119 mg/kgVCVGH* -,504,1990

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/hamster lowest published toxic concentration: 162 ppm/6H/4W- intermittentLiver: Hepatitis (hepatocellular necrosis), zonal

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
TXAPA9 46,375,1978
inhalation/hamster lowest published toxic concentration: 50 ppm/6H/78W- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainINHTE5 10,443,1998
inhalation/mouse lowest published toxic concentration: 3 ppm/5D- intermittentLung, Thorax, or Respiration: Other changesTOXID9 -,207,2009
inhalation/mouse lowest published toxic dose: 1260 mg/m3/14D- intermittentEndocrine: Changes in thymus weight

Immunological Including Allergic: Decrease in cellular immune response

Immunological Including Allergic: Decrease in humoral immune response
ZYYZEW 3,125,1989
inhalation/mouse lowest published toxic concentration: 200 mg/m3/24H/91D- continuousGastrointestinal: Ulceration or bleeding from large intestine

Blood: Changes in spleen

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
JIHTAB 18,240,1936
inhalation/rat lowest published toxic concentration: 161 ppm/6H/4W- intermittentLiver: Changes in liver weight

Kidney, Ureter, and Bladder: Changes in bladder weight

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
TXAPA9 46,375,1978
inhalation/rat lowest published toxic concentration: 220 µg/m3/24H/60D- continuousBrain and Coverings: Other degenerative changes

Liver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Phosphatases
GISAAA 29(9),13,1964
inhalation/rat lowest published toxic concentration: 200 mg/m3/24H/91D- continuousBrain and Coverings: Other degenerative changes

Gastrointestinal: Ulceration or bleeding from large intestine

Blood: Changes in spleen
JIHTAB 18,240,1936
inhalation/rat lowest published toxic concentration: 50 ppm/6H/2Y- intermittentLung, Thorax, or Respiration: Changes in lung weight

Skin and Appendages: Other: Hair

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
INHTE5 10,443,1998
inhalation/rat lowest published toxic concentration: 32 ppm/6H/16D- intermittentOlfaction: Other olfaction effectsNTPTR* NTP-TR-467,1998
inhalation/rat lowest published toxic concentration: 0.039 gm/m3/48D- intermittentKidney, Ureter, and Bladder: Other changes in urine compositionTPKVAL 13,58,1973
intraperitoneal/rat lowest published toxic dose: 168 mg/kg/21D- intermittentBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Liver: Other changes

Blood: Other changes
WDZAEK 6,126,1992
oral/mouse lowest published toxic dose: 63 mg/m3/21D- intermittentImmunological Including Allergic: Decreased immune responseZYYZEW 2,57,1988
oral/rat lowest published toxic dose: 9100 µg/kg/26W- intermittentLiver: Changes in liver weight

Endocrine: Changes in spleen weight

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Dehydrogenases
GISAAA 45(2),17,1980
oral/rat lowest published toxic dose: 1680 mg/kg/3W- intermittentLiver: Hepatitis (hepatocellular necrosis), diffuse

Liver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Hepatic microsomal mixed oxidase (dealkylation, hydroxylation, etc.)
ZYYZEW 9,283,1995
subcutaneous/mouse lowest published toxic dose: 42 mg/kg/21D- intermittentImmunological Including Allergic: Decreased immune response

Biochemical: Metabolism (intermediary): Other proteins
ZYYZEW 2,57,1988

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 10 ppm (skin)DTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)Cancer Review:Animal Sufficient EvidenceIMEMDT 71,227,1999
International Agency for Research on Cancer (IARC)Cancer Review:Animal Inadequate EvidenceIMEMDT 19,131,1979
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 19,131,1979
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 71,227,1999
International Agency for Research on Cancer (IARC)Cancer Review:Group 2BIMEMDT 71,227,1999
TOXICOLOGY REVIEWCTOXAO 13,153,1978
TOXICOLOGY REVIEWCBINA8 135-136,81,2001
TOXICOLOGY REVIEWCBINA8 135-136,27,2001
TOXICOLOGY REVIEWMUREAV 543,201,2003
TOXICOLOGY REVIEWMUREAV 567,109,2004
TOXICOLOGY REVIEWMUREAV 567,347,2004
TOXICOLOGY REVIEWHETOEA 25,413,2006
TOXICOLOGY REVIEWREPTED 25,192,2008
TOXICOLOGY REVIEWMUREAV 566,49,2004
TOXICOLOGY REVIEWMUREAV 682,94,2009
TOXICOLOGY REVIEWNTAPM* -,629,1995
TOXICOLOGY REVIEWMUREAV 751,49,2012
TOXICOLOGY REVIEWTOLED5 204,148,2011

Standards and Regulations

OrganizationStandardReference
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 25 ppm (90 mg/m3) (skin)DTLVS* 3,54,1971
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-AUSTRALIAtime-weighted average 10 ppm (36 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 5 ppm (18 mg/m3);KZW 20 ppm (72 mg/m3), skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 10 ppm (37 mg/m3), Skin, MAR2002
Occupational Exposure Limit-DENMARKceiling concentration 1 ppm (3.6 mg/m3), skin, carc, MAY2011
Occupational Exposure Limit-FINLANDtime-weighted average 1 ppm (3.7 mg/m3), short term exposure limit 5 ppm (18 mg/m3), NOV2011
Occupational Exposure Limit-FRANCEVME 10 ppm (36 mg/m3), C2 Carcinogen, FEB2006
Occupational Exposure Limit-HUNGARYtime-weighted average 18 mg/m3, short term exposure limit 72 mg/m3, SEP2000
Occupational Exposure Limit-ICELANDshort term exposure limit 1 ppm (3.6 mg/m3), skin, NOV2011
Occupational Exposure Limit-JAPAN2B carc, MAY2012
Occupational Exposure Limit-KOREAtime-weighted average 10 ppm (35 mg/m3), skin, 2006
Occupational Exposure Limit-MEXICOtime-weighted average 10 ppm (45 mg/m3) (skin), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 10 ppm (36 mg/m3), skin, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 1 ppm (3.6 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 10 ppm (36 mg/m3), JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 2 mg/m3, short term exposure limit, 16 mg/m3, JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 2 mg/m3, JUN2003
Occupational Exposure Limit-SWEDENtime-weighted average 1 ppm (3.5 mg/m3);short term exposure limit 5 ppm (18 mg/m3), Skin, JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 5 ppm (18 mg/m3), carc 2, skin, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 18 mg/m3, Skin, 2003
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 25 ppm (90 mg/m3) (skin)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)8H time-weighted average 25 ppm (90 mg/m3) (skin)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 25 ppm (90 mg/m3) (skin)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 25 ppm (90 mg/m3) (skin)CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO beta-CHLOROPRENE-airCarcinogen ceiling concentration 1 ppmNIOSH* DHHS #95-121,1995
National Occupational Exposure Survey 1983Hazard Code 18260; Number of Industries 17; Total Number of Facilities 1864; Number of Occupations 21; Total Number of Employees Exposed 17750; Total Number of Female Employees Exposed 654
National Occupational Hazard Survey 1974Hazard Code 18260; Number of Industries 39; Total Number of Facilities 3538; Number of Occupations 26; Total Number of Employees Exposed 43712

Status in Federal Agencies

OrganizationReference
EPA GENETOX PROGRAM 1988, Positive: Cell transform.-SA7/SHE; Sperm morphology-rat
EPA GENETOX PROGRAM 1988, Positive: D melanogaster Sex-linked lethal
EPA TSCA 8(a) PRELIMINARY ASSESSMENT INFORMATION, FINAL RULEFEREAC 47,26992,82
EPA TSCA Section 8(b) CHEMICAL INVENTORY
EPA TSCA Section 8(d) unpublished health/safety studies
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
NCI Carcinogenesis Studies (inhal);clear evidence:mouse,rat
NIOSH Analytical Method, 1994: beta-Chloroprene, 1002
NIOSH CURRENT INTELLIGENCE BULLETIN 1, 1975
NTP 14th Report on Carcinogens,2016:Reasonably anticipated to be human carcinogen
On EPA IRIS database
OSHA ANALYTICAL METHOD #112
Page last reviewed: November 16, 2018