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Chlorine

RTECS #
FO2100000
CAS #
7782-50-5
See: NMAM or OSHA Methods
Updated
March 2019
Molecular Weight
70.90
Molecular Formula
Cl2
Synonyms
Bertholite
Chloor (Dutch)
Chlor (German)
Chlore (French)
Chlorinated water
Chlorine (ACGIH:OSHA)
Chlorine mol.
Cloro (Italian)
Molecular chlorine

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic Analysislymphocyte/human20 ppmCBINA8 6,375,1973
mutation in microorganisms/Salmonella typhimurium1800 µg/L (-enzymatic activation step)OZSEDS 8,217,1986
sperm morphologyoral/mouse20 mg/kg/5D-continuousENMUDM 7,201,1985

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
oral/rat 565 mg/kg (8W male/2W pre-3W after birth)Reproductive: Effects on newborn: Biochemical and metabolicTJADAB 35,43A,1987

Tumorigenic Data and References

Route/OrganismDoseEffectReference
inhalation/monkey lowest published toxic concentration: 2300 ppb/6H/1Y- intermittentTumorigenic: Neoplastic by RTECS criteria

Lung, Thorax, or Respiration: Tumors
NTIS** OTS0571476
oral/rat lowest published toxic dose: 5047 mg/kg/103W- continuousTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Blood: Leukemia
NTIS** PB92-191659
oral/rat lowest published toxic dose: 5096 mg/kg/2Y- continuousTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Blood: Leukemia
NTPTR* NTP-TR-392,1992

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/cat lowest published toxic concentration: 870 mg/m3/1HLung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Respiratory obstruction

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/cat lowest published toxic concentration: 29 mg/m3Lung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Other changes

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/Dog Lowest published lethal concentration: 800 ppm/30MBehavioral: Muscle weakness

Gastrointestinal: Nausea or vomiting

Lung, Thorax, or Respiration: Dyspnea
JPETAB 14,65,1919
inhalation/Dog lowest published toxic concentration: 145 mg/m3/30MLung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Respiratory obstruction

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/domestic animal lowest published toxic concentration: 60 ppm/30MLung, Thorax, or Respiration: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects
TOXID9 12,404,2008
inhalation/domestic animal lowest published toxic concentration: 90 ppm/30MCardiac: Other changes

Liver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects
TOXID9 12,404,2008
inhalation/guinea pig Lowest published lethal concentration: 3200 ppm/3HAHYGAJ 7,231,1887
inhalation/guinea pig lowest published toxic concentration: 870 mg/m3/1HLung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Respiratory obstruction

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/guinea pig lowest published toxic concentration: 29 mg/m3Lung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Other changes

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/horse, donkey Lowest published lethal concentration: 2900 mg/m3/35MLung, Thorax, or Respiration: Emphysema

Lung, Thorax, or Respiration: Acute pulmonary edema

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/human Lowest published lethal concentration: 2900 mg/m3/5MVCVN5* -,373,1989
inhalation/human Lowest published lethal concentration: 100 mg/m3/30MVCVN5* -,373,1989
inhalation/human lowest published toxic concentration: 0.9 mg/m3Lung, Thorax, or Respiration: CoughVCVN5* -,373,1989
inhalation/human lowest published toxic concentration: 500 ppb/2D- intermittentBehavioral: ToleranceJAPYAA 54,1120,1983
inhalation/human Lowest published lethal concentration: 2530 mg/m3/30MLung, Thorax, or Respiration: Structural or functional change in trachea or bronchi

Lung, Thorax, or Respiration: Emphysema

Lung, Thorax, or Respiration: Chronic pulmonary edema or congestion
28ZOAH -,150,1937
inhalation/human Lowest published lethal concentration: 500 ppm/5MTABIA2 3,231,1933
inhalation/human lowest published toxic concentration: 66 ppm/1HBehavioral: Headache

Lung, Thorax, or Respiration: Cough

Lung, Thorax, or Respiration: Dyspnea
DICYE7 4,28,1988
inhalation/mammal (species unspecified) Lowest published lethal concentration: 500 ppm/5MAEPPAE 138,65,1928
inhalation/mouse Lowest published lethal concentration: 1100 mg/m3/10MLung, Thorax, or Respiration: Emphysema

Lung, Thorax, or Respiration: Acute pulmonary edema

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/mouse lethal concentration (50 percent kill): 368 mg/m3/30MLung, Thorax, or Respiration: Emphysema

Lung, Thorax, or Respiration: Acute pulmonary edema

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/mouse lethal concentration (50 percent kill): 137 ppm/1HAMRL** TR-72-62,1972
inhalation/mouse lowest published toxic concentration: 50 ppm/15MBehavioral: Sleep

Nutritional and Gross Metabolic: Body temperature decrease

Lung, Thorax, or Respiration: Acute pulmonary edema
TXCYAC 303,34,2013
inhalation/mouse lowest published toxic concentration: 200 ppm/15MLung, Thorax, or Respiration: Fibrosis, focal (pneumoconiosis)TXCYAC 303,34,2013
inhalation/mouse lowest published toxic concentration: 228 ppm/1HLung, Thorax, or Respiration: Acute pulmonary edemaTXAPA9 263,251,2012
inhalation/mouse lowest published toxic concentration: 60 ppm/1HLung, Thorax, or Respiration: Other changes

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TXAPA9 278,53,2015
inhalation/mouse lowest published toxic concentration: 200 ppm/15MLung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Other changes

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TXAPA9 271,168,2013
inhalation/mouse lowest published toxic concentration: 0.6 ppm/15MOlfaction: Other olfaction effects

Lung, Thorax, or Respiration: Respiratory obstruction

Lung, Thorax, or Respiration: Respiratory stimulation
TOXID9 78,439,2004
inhalation/mouse lowest published toxic concentration: 50 ppm/15MLung, Thorax, or Respiration: Other changes

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TOLED5 282,1,2018
inhalation/rabbit lowest published toxic concentration: 400 ppm/8MLung, Thorax, or Respiration: Other changesTXAPA9 315,1,2017
inhalation/rabbit lowest published toxic concentration: 29 mg/m3Lung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Other changes

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/rabbit lowest published toxic concentration: 870 mg/m3/1HLung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Respiratory obstruction

Nutritional and Gross Metabolic: Body temperature decrease
VCVN5* -,373,1989
inhalation/rat lethal concentration (50 percent kill): 293 ppm/1HAMRL** TR-72-62,1972
inhalation/rat lowest published toxic concentration: 3 mg/m3Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects
VCVN5* -,375,1989
inhalation/rat lowest published toxic concentration: 10 mg/m3Lung, Thorax, or Respiration: CoughVCVN5* -,375,1989
inhalation/rat lowest published toxic concentration: 400 ppm/30MNutritional and Gross Metabolic: Body temperature decrease

Lung, Thorax, or Respiration: Respiratory depression

Lung, Thorax, or Respiration: Other changes
TXCYAC 310,104,2013
inhalation/rat lowest published toxic dose: 1330 ppm/15MLung, Thorax, or Respiration: Fibrosis (interstitial)

Lung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Pleural thickening
INHTE5 16,911,2004
inhalation/rat lowest published toxic concentration: 1330 ppm/15MLung, Thorax, or Respiration: Fibrosis (interstitial)

Lung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Pleural thickening
INHTE5 16,911,2004
inhalation/rat lowest published toxic concentration: 413 ppm/30MLung, Thorax, or Respiration: Respiratory depression

Cardiac: Change in rate

Lung, Thorax, or Respiration: Changes in lung weight
TXCYAC 326,109,2014
inhalation/rat Lowest published lethal concentration: 413 ppm/30MTXCYAC 326,109,2014
inhalation/rat lowest published toxic concentration: 400 ppm/30MVascular: Contraction (isolated tissue)

Lung, Thorax, or Respiration: Respiratory depression

Vascular: Other changes
TXCYAC 321,96,2014
multiple/rabbit lowest published lethal dose: 600 ppm/45MLung, Thorax, or Respiration: Other changes

Biochemical: Metabolism (intermediary): Other proteins

Biochemical: Metabolism (intermediary): Effect on inflammation or mediation of inflammation
TOLED5 271,20,2017
oral/human lowest published toxic dose: 2.9 mg/kgSkin: After topical application: Primary irritationVCVN5* -,374,1989

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/monkey lowest published toxic concentration: 2300 ppb/6H/1Y- intermittentOlfaction: Other olfaction effects

Eye: Conjunctiva irritation

Lung, Thorax, or Respiration: Other changes
FAATDF 9,557,1987
inhalation/mouse lowest published toxic concentration: 9100 ppb/6H/5D- intermittentOlfaction: Other olfaction effects

Lung, Thorax, or Respiration: Structural or functional change in trachea or bronchi

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
TXAPA9 71,225,1983
inhalation/mouse lowest published toxic concentration: 400 ppb/6H/2Y- intermittentOlfaction: Other olfaction effectsNTIS** OTS0538318
inhalation/rabbit lowest published toxic concentration: 1.7 mg/m3/5H/38W- intermittentLung, Thorax, or Respiration: Emphysema

Liver: Other changes

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
VCVN5* -,375,1989
inhalation/rat lowest published toxic concentration: 3 mg/m3/24H/5D- continuousNutritional and Gross Metabolic: Weight loss or decreased weight gain

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Multiple enzyme effects
VCVN5* -,375,1989
inhalation/rat lowest published toxic concentration: 10 mg/m3/24H/5D- continuousLung, Thorax, or Respiration: CoughVCVN5* -,375,1989
inhalation/rat lowest published toxic concentration: 26 mg/m3/6H/6W- intermittentLung, Thorax, or Respiration: Structural or functional change in trachea or bronchiVCVN5* -,375,1989
inhalation/rat lowest published toxic concentration: 2.9 mg/m3/6H/6W- intermittentOlfaction: Other olfaction effectsVCVN5* -,375,1989
inhalation/rat lowest published toxic concentration: 9100 ppb/6H/5D- intermittentOlfaction: Other olfaction effects

Lung, Thorax, or Respiration: Structural or functional change in trachea or bronchi

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
TXAPA9 71,225,1983
inhalation/rat lowest published toxic concentration: 400 ppb/6H/2Y- intermittentOlfaction: Other olfaction effectsNTIS** OTS0538318
inhalation/rat lowest published toxic concentration: 9 ppm/6H/6W- intermittentKidney, Ureter, and Bladder: Other changes

Blood: Changes in leukocyte (WBC) count

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Phosphatases
TXAPA9 49,77,1979
oral/mouse lowest published toxic dose: 153 gm/kg/73W- continuousCardiac: Changes in heart weight

Kidney, Ureter, and Bladder: Changes in bladder weight

Related to Chronic Data: Changes in ovarian weight
FCTOD7 21,435,1983
oral/rat lowest published toxic dose: 7568 mg/kg/28D- continuousBehavioral: Food intake (animal)

Liver: Changes in liver weight

Kidney, Ureter, and Bladder: Changes in bladder weight
FCTOD7 21,423,1983
oral/rat lowest published toxic dose: 42 gm/kg/2W- continuousBrain and Coverings: Changes in brain weight

Liver: Changes in liver weight

Kidney, Ureter, and Bladder: Changes in bladder weight
JTEHD6 2,1161,1977
oral/rat lowest published toxic dose: 3312 mg/kg/92D- continuousBlood: Change in clotting factorsJTEHD6 20,401,1987
oral/rat lowest published toxic dose: 109 gm/kg/2Y- continuousEndocrine: Changes in spleen weight

Blood: Changes in other cell count (unspecified)

Biochemical: Metabolism (intermediary): Plasma proteins not involving coagulation
FCTOD7 21,427,1983
oral/rat lowest published toxic dose: 136.5 mg/kg/13W- continuousLung, Thorax, or Respiration: Other changes

Liver: Other changes
VCVN5* -,375,1989
oral/rat lowest published toxic dose: 36.2 gm/kg/69W- continuousBlood: Normocytic anemiaVCVN5* -,375,1989
oral/rat lowest published toxic dose: 30.2 gm/kg/69W- continuousBlood: Changes in platelet countVCVN5* -,375,1989

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 0.5 ppm;short term exposure limit 1 ppmDTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWCPEMM* 3,239,2002
TOXICOLOGY REVIEWCHHSA* 9,24,2002
TOXICOLOGY REVIEWDIMON* 46,551,2000
TOXICOLOGY REVIEWENTOX* -,553,2005
TOXICOLOGY REVIEWHUTOX* -,661,1996
TOXICOLOGY REVIEWHUTOX* -,671,1996
TOXICOLOGY REVIEWHUTOX* -,683,1996
TOXICOLOGY REVIEWHTCWA* 2,313,
TOXICOLOGY REVIEWCCACL* 21,719,2005
TOXICOLOGY REVIEWTOLED5 198,297,2010
TOXICOLOGY REVIEWTOLED5 204,148,2011
TOXICOLOGY REVIEWRTOPDW 54,247,2009
TOXICOLOGY REVIEWRTOPDW 54,294,2009
TOXICOLOGY REVIEWVETODR ,215,2018

Standards and Regulations

OrganizationStandardReference
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1988 PESTICIDE SUBJECT TO REGISTRATION OR RE-REGISTRATIONFEREAC 54,7740,1989
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1998 STATUS OF PESTICIDESRED CompletedRBREV* -,301,1998
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 1 ppm (3 mg/m3)DTLVS* 3,46,1971
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-ARAB Republic of Egypttime-weighted average 1 ppm (3 mg/m3), JAN1993
Occupational Exposure Limit-AUSTRALIAceiling concentration 1 ppm (3 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-KZW 0.5 ppm (1.5 mg/m3), 2007
Occupational Exposure Limit-BELGIUMshort term exposure limit 0.5 ppm (1.5 mg/m3), MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 0.5 ppm (1.5 mg/m3), MAY2011
Occupational Exposure Limit-ECshort term exposure limit 1.5 mg/m3 (0.5 ppm), FEB2006
Occupational Exposure Limit-FINLANDshort term exposure limit 0.5 ppm (1.5 mg/m3), NOV2011
Occupational Exposure Limit-FRANCEVLE 1 ppm (3 mg/m3), FEB2006
Occupational Exposure Limit-GERMANYMAK 0.5 ppm (1.5 mg/m3), 2011
Occupational Exposure Limit-HUNGARYtime-weighted average 1.5 mg/m3, short term exposure limit 1.5 mg/m3, SEP2000
Occupational Exposure Limit-ICELANDshort term exposure limit 0.5 ppm (1.5 mg/m3), NOV2011
Occupational Exposure Limit-INDIAtime-weighted average 1 ppm (3 mg/m3), short term exposure limit 3 ppm (9 mg/m3), JAN1993
Occupational Exposure Limit-JAPANceiling concentration 0.5 ppm (1.5 mg/m3), MAY2012
Occupational Exposure Limit-KOREAtime-weighted average 1 ppm (3 mg/m3), short term exposure limit 3 ppm (9 mg/m3), 2006
Occupational Exposure Limit-MEXICOtime-weighted average 1 ppm (3 mg/m3);short term exposure limit 3 ppm (9 mg/m3), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 0.5 ppm (1.5 mg/m3); short term exposure limit 1 ppm (2.9 mg/m3), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 0.5 ppm (1.5 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 0.5 ppm (1.45 mg/m3); short term exposure limit 1 ppm (3 mg/m3), JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 1.5 mg/m3, short term exposure limit 9 mg/m3, JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 1 mg/m3, Skin, JUN2003
Occupational Exposure Limit-SWEDENtime-weighted average 0.5 ppm (1.5 mg/m3), ceiling concentration 1 ppm (3 mg/m3), JUN2005
Occupational Exposure Limit-SWITZERLANDceiling concentration 0.5 ppm (1.5 mg/m3), JAN2011
Occupational Exposure Limit-THAILANDtime-weighted average 1 ppm (3 mg/m3), JAN1993
Occupational Exposure Limit-THE NETHERLANDSMAC-C 3 mg/m3, 2003
Occupational Exposure Limit-THE PHILIPPINEStime-weighted average 1 ppm (3 mg/m3), JAN1993
Occupational Exposure Limit-TURKEYtime-weighted average 1 ppm (3 mg/m3), JAN1993
Occupational Exposure Limit-UNITED KINGDOMshort term exposure limit 0.5 ppm (1.5 mg/m3), OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)ceiling concentration 1 ppm (3 mg/m3)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)ceiling concentration 1 ppm (3 mg/m3)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)ceiling concentration 1 ppm (3 mg/m3)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)ceiling concentration 1 ppm (3 mg/m3)CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO CHLORINE-air10H time-weighted average 0.5 ppm;short term exposure limit 1 ppmNIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code X9656; Number of Industries 3; Total Number of Facilities 338; Number of Occupations 6; Total Number of Employees Exposed 4768; Total Number of Female Employees Exposed 1862
National Occupational Exposure Survey 1983Hazard Code 18040; Number of Industries 70; Total Number of Facilities 5343; Number of Occupations 75; Total Number of Employees Exposed 178105; Total Number of Female Employees Exposed 20221
National Occupational Hazard Survey 1974Hazard Code 18040; Number of Industries 169; Total Number of Facilities 21429; Number of Occupations 86; Total Number of Employees Exposed 220544

Status in Federal Agencies

OrganizationReference
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 (water);equivocal evidence:rat
NCI Carcinogenesis Studies (water);no evidence:mouse
NIOSH Analytical Method, 1994: Bromine and chlorine, 6011
On EPA IRIS database
OSHA ANALYTICAL METHOD #ID-101
Page last reviewed: November 16, 2018