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Benzene, o-dichloro-

RTECS #
CZ4500000
CAS #
95-50-1
See: NMAM or OSHA Methods
Updated
June 2018
Molecular Weight
147.00
Molecular Formula
C6H4Cl2
Synonyms
1,2-Dichlorobenzene
Benzene, 1,2-dichloro-
Chloroben
Dilatin DB
Dizene
Dowtherm E
NCI-C54944
o-Dichlor benzol
o-Dichlorbenzene
o-Dichlorobenzene
o-Dichlorobenzene (ACGIH:OSHA)
Orthodichlorobenzene
Orthodichlorobenzol
Special termite fluid
Termitkil

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
eye /rabbit 100 mg/30S rinse mildAMIHAB 17,180,1958

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
gene conversion and mitotic recombination/Saccharomyes cerevisiae1 mmol/LMUREAV 413,205,1998
micronucleus testintraperitoneal/mouse187 mg/kgHPV173 -,-,2002
micronucleus testintraperitoneal/mouse187 mg/kg/24HMUTAEX 2,111,1987
mutation in microorganismslymphocyte/mouse6500 µg/L (+enzymatic activation step)SCIEAS 236,933,1987
sister chromatid exchangeovary/hamster59 mg/LSCIEAS 236,933,1987
specific locus testinhalation/mouse68 µmol/LMUREAV 608,29,2006
sperm morphologyintraperitoneal/rat250 mg/kgJACTDZ 4(2),224,1985

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
inhalation/rat 50 ppm (multigeneration)Reproductive: Other effects on male

Reproductive: Other effects on female
HPV173 -,-,2002
inhalation/rat 150 ppm (multigeneration)Reproductive: Other effects on male

Reproductive: Other effects on female

Reproductive: Effects on newborn: Viability index (e.g., # alive at day 4 per # born alive)
HPV173 -,-,2002
inhalation/rat 100 ppm (6-15D pregnant)Reproductive: Other effects on femaleHPV173 -,-,2002
inhalation/rat 400 ppm (6-15D pregnant)Reproductive: Other effects on female

Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)

Reproductive: Specific developmental abnormalities: Musculoskeletal system
HPV173 -,-,2002
inhalation/rabbit 100 ppm (6-18D pregnant)Reproductive: Other effects on femaleHPV173 -,-,2002
inhalation/rat 200 ppm/6H (6-15D pregnant)Reproductive: Specific developmental abnormalities: Musculoskeletal systemFAATDF 5,190,1985
inhalation/rat 500 ppm/6H (6-15D pregnant)Reproductive: Other effects on female

Reproductive: Effects on embryo or fetus: Fetal death
NTIS** OTS0535228
intraperitoneal/rat 50 mg/kg (1D male)Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)JACTDZ 4(1),224,1985

Tumorigenic Data and References

Route/OrganismDoseEffectReference
oral/rat lowest published toxic dose: 30900 mg/kg/103W- intermittentTumorigenic: Neoplastic by RTECS criteria

Endocrine: Adrenal cortex tumors
NTIS** PB86-144888/AS

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, melanoma Inhibitor Concentration (50 percent kill): >2500 mg/L/48HIn Vitro Toxicity Studies: Cell viability (lysosomal damage): neutral red assay etc.FCTOD7 50,2084,2012
In Vitro/Mouse, fibroblast Inhibitor Concentration (50 percent kill): >17.0 mmol/L/48HIn Vitro Toxicity Studies: Cell viability (lysosomal damage): neutral red assay etc.TIVIEQ 27,1357,2013
In Vitro/paaInhibitor Concentration Low: 185 µmol/L/44HIn Vitro Toxicity Studies: Other assaysTIVIEQ 27,1416,2013
inhalation/guinea pig Lowest published lethal concentration: 800 ppm/24HLiver: Hepatitis (hepatocellular necrosis), diffuseJPBAA7 44,281,1937
inhalation/mouse lethal concentration (50 percent kill): 1236 ppm/6HHPV173 -,-,2002
inhalation/rat lethal concentration (50 percent kill): 8150 mg/m3/4HPeripheral Nerve and Sensation: Flaccid paralysis without anesthesia (usually neuromuscular blockage)

Behavioral: General anesthetic

Behavioral: Muscle contraction or spasticity
VCVGK* -,24,1984
inhalation/rat lethal concentration (50 percent kill): 1532 ppm/6HHPV173 -,-,2002
inhalation/rat Lowest published lethal concentration: 821 ppm/7HBehavioral: General anesthetic

Liver: Hepatitis (hepatocellular necrosis), zonal

Eye: Lacrimation
AMIHAB 17,180,1958
intraperitoneal/mouse lethal dose (50 percent kill): 1228 mg/kgMUTAEX 2,111,1987
intraperitoneal/rat lethal dose (50 percent kill): 840 mg/kgMEPAAX 20,519,1969
intraperitoneal/rat lowest published toxic dose: 735 mg/kgVCVGK* -,24,1984
intraperitoneal/rat lowest published toxic dose: 1 mg/kgLiver: Other changes

Liver: Changes in liver weight

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
TXAPA9 111,69,1991
intraperitoneal/rat lowest published toxic dose: 735 mg/kgGastrointestinal: Changes in structure or function of exocrine pancreas

Gastrointestinal: Other changes
VCVGK* -,24,1984
intravenous/mouse lowest published lethal dose: 400 mg/kgJPBAA7 44,281,1937
intravenous/rabbit lowest published lethal dose: 250 mg/kgJPBAA7 44,281,1937
oral/guinea pig lowest published lethal dose: 2000 mg/kgHPV173 -,-,2002
oral/mouse lethal dose (50 percent kill): 4386 mg/kgYKYUA6 32,471,1981
oral/rabbit lethal dose (50 percent kill): 500 mg/kg85ARAE 3,32,1976/1977
oral/rat lethal dose (50 percent kill): 500 mg/kgWRPCA2 9,119,1970
skin/rabbit lethal dose (50 percent kill): >10 gm/kgNTIS** OTS0521597
subcutaneous/rat lethal dose (50 percent kill): 5 gm/kgTSCAT* OTS 205976

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/rat lowest published toxic concentration: 290 mg/m3/7H/26W- intermittentLiver: Other changesVCVGK* -,24,1994
inhalation/rat lowest published toxic concentration: 200 mg/m3/4H/17W- intermittentBrain and Coverings: Other degenerative changes

Blood: Changes in cell count (unspecified)
VCVGK* -,24,1994
inhalation/rat lowest published toxic concentration: 93 ppm/24W- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainHPV173 -,-,2002
oral/mouse lowest published toxic dose: 16250 mg/kg/13W- intermittentLiver: Hepatitis (hepatocellular necrosis), diffuse

Blood: Changes in leukocyte (WBC) count
HPV173 -,-,2002
oral/mouse lowest published toxic dose: 32500 mg/kg/13W- intermittentLiver: Hepatitis (hepatocellular necrosis), diffuse

Blood: Changes in leukocyte (WBC) count

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
HPV173 -,-,2002
oral/mouse lowest published toxic dose: 7 gm/kg/14D- intermittentLiver: Fatty liver degeneration

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
NTPTR* NTP-TR-255,1985
oral/mouse lowest published toxic dose: 32500 mg/kg/13W- intermittentLiver: Changes in liver weight

Endocrine: Changes in spleen weight
NTPTR* NTP-TR-255,1985
oral/rat lowest published toxic dose: 27300 µg/kg/39W- intermittentKidney, Ureter, and Bladder: Other changes in urine composition

Blood: Angranulocytosis

Blood: Changes in erythrocyte (RBC) count
GISAAA 33(10),15,1968
oral/rat lowest published toxic dose: 3 gm/kg/10D- intermittentLiver: Changes in liver weight

Endocrine: Changes in spleen weight

Blood: Changes in leukocyte (WBC) count
DCTODJ 14,83,1991
oral/rat lowest published toxic dose: 32500 mg/kg/13W- intermittentLiver: Changes in liver weight

Endocrine: Changes in spleen weight

Blood: Changes in erythrocyte (RBC) count
NTPTR* NTP-TR-255,1985
oral/rat lowest published toxic dose: 9000 mg/kg/90D- intermittentLiver: Changes in liver weight

Kidney, Ureter, and Bladder: Changes in kidney weight

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Transaminases
HPV173 -,-,2002
oral/rat lowest published toxic dose: 36000 mg/kg/90D- intermittentLiver: Hepatitis (hepatocellular necrosis), diffuse

Kidney, Ureter, and Bladder: Changes in kidney weight

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Transaminases
HPV173 -,-,2002
oral/rat lowest published toxic dose: 8125 mg/kg/13W- intermittentLiver: Hepatitis (hepatocellular necrosis), diffuse

Liver: Changes in liver weight

Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)
HPV173 -,-,2002
oral/rat lowest published toxic dose: 32500 mg/kg/13W- intermittentLiver: Hepatitis (hepatocellular necrosis), diffuse

Liver: Changes in liver weight

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
HPV173 -,-,2002

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 25 ppm;short term exposure limit 50 ppmDTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 7,231,1974
International Agency for Research on Cancer (IARC)Cancer Review:Animal Inadequate EvidenceIMEMDT 7,231,1974
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 29,213,1982
International Agency for Research on Cancer (IARC)Cancer Review:Animal Inadequate EvidenceIMEMDT 29,213,1982
International Agency for Research on Cancer (IARC)Cancer Review:Animal No Cancer EvidenceIMEMDT 73,223,1999
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 73,223,1999
International Agency for Research on Cancer (IARC)Cancer Review:Group 3IMEMDT 73,223,1999
TOXICOLOGY REVIEWENTOX* -,5,2005
TOXICOLOGY REVIEWMUREAV 584,1,2005
TOXICOLOGY REVIEWMUREAV 682,94,2009
TOXICOLOGY REVIEWMUREAV 741,32,2012
TOXICOLOGY REVIEWMUREAV 721,27,2011
TOXICOLOGY REVIEWMUREAV 763,36,2014
TOXICOLOGY REVIEWFCTOD7 55,596,2013
TOXICOLOGY REVIEWMUTAEX 32,491,2017

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 PESTICIDESCancelledRBREV* -,249,1998
Mine Safety and Health Administration (MSHA) STANDARDair-ceiling concentration 50 ppm (300 mg/m3)DTLVS* 3,76,1971
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 25 ppm (150 mg/m3), short term exposure limit 50 ppm (301 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 20 ppm (122 mg/m3);KZW 50 ppm (306 mg/m3), skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 20 ppm (122 mg/m3), MAR2002
Occupational Exposure Limit-BELGIUMshort term exposure limit 50 ppm (306 mg/m3), Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 20 ppm (122 mg/m3), skin, MAY2011
Occupational Exposure Limit-ECtime-weighted average 122 mg/m3 (20 ppm);short term exposure limit 306 mg/m3 (50 ppm), skin, JUN2000
Occupational Exposure Limit-FINLANDtime-weighted average 10 ppm (61 mg/m3), short term exposure limit 50 ppm (300 mg/m3), skin, NOV2011
Occupational Exposure Limit-FRANCEVME 20 ppm (122 mg/m3), VLE 50 ppm (306 mg/m3), Skin, FEB2006
Occupational Exposure Limit-GERMANYMAK 10 ppm (61 mg/m3), skin, 2011
Occupational Exposure Limit-HUNGARYtime-weighted average 122 mg/m3, short term exposure limit 306 mg/m3, Skin, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 20 ppm (122 mg/m3), short term exposure limit 50 ppm (306 mg/m3), skin, NOV2011
Occupational Exposure Limit-JAPANOccupational Exposure Limit 25 ppm (150 mg/m3), MAY2012
Occupational Exposure Limit-KOREAceiling concentration 50 ppm (300 mg/m3), 2006
Occupational Exposure Limit-MEXICOtime-weighted average 50 ppm (300 mg/m3), 2004
Occupational Exposure Limit-NEW ZEALANDceiling concentration 50 ppm (301 mg/m3), skin, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 25 ppm (150 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 25 ppm (150 mg/m3); short term exposure limit 50 ppm (301 mg/m3), JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 20 mg/m3, MAC(CEILING) 300 mg/m3, JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 50 mg/m3, JUN2003
Occupational Exposure Limit-SWEDENtime-weighted average 25 ppm (150 mg/m3), ceiling concentration 50 ppm (300 mg/m3), JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 10 ppm (61 mg/m3), KZG-week 20 ppm (122 mg/m3), skin, JAN2011
Occupational Exposure Limit-THAILANDtime-weighted average 50 ppm (300 mg/m3), JAN1993
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 122 mg/m3, 2003
Occupational Exposure Limit-THE PHILIPPINEStime-weighted average 50 ppm (300 mg/m3), JAN1993
Occupational Exposure Limit-TURKEYtime-weighted average 50 ppm (300 mg/m3), JAN1993
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 25 ppm (153 mg/m3);short term exposure limit 50 ppm (306 mg/m3), skin, OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)ceiling concentration 50 ppm (300 mg/m3)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)ceiling concentration 50 ppm (300 mg/m3)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)ceiling concentration 50 ppm (300 mg/m3)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)ceiling concentration 50 ppm (300 mg/m3)CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO o-DICHLOROBENZENE-airceiling concentration 50 ppmNIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code 24003; Number of Industries 59; Total Number of Facilities 10577; Number of Occupations 59; Total Number of Employees Exposed 92246; Total Number of Female Employees Exposed 12686
National Occupational Hazard Survey 1974Hazard Code 24003; Number of Industries 83; Total Number of Facilities 8838; Number of Occupations 69; Total Number of Employees Exposed 72149

Status in Federal Agencies

OrganizationReference
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 (gavage);no evidence:mouse,rat
NIOSH Analytical Method, 1994: Hydrocarbons, halogenated, 1003
NIOSH Analytical Method, 1996: Volatile organic compound, 2549
On EPA IRIS database
Page last reviewed: November 16, 2018