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Pyrocatechol

RTECS #
UX1050000
CAS #
120-80-9
See: NMAM or OSHA Methods
Updated
December 2018
Molecular Weight
110.12
Molecular Formula
C6H6O2
Synonyms
1,2-Benzenediol
1,2-Dihydroxybenzene
2-Hydroxyphenol
Benzene, o-dihydroxy-
C.I. 76500
C.I. Oxidation Base 26
Catechin (phenol)
Catechol
Catechol (ACGIH)
Catechol (phenol)
Durafur developer C
Fouramine PCH
Fourrine 68
Katechol (Czech)
NCI-C55856
o-Benzenediol
o-Dihydroxybenzene
o-Dioxybenzene
o-Diphenol
o-Hydroquinone
o-Hydroxyphenol
o-Phenylenediol
Oxyphenic acid
Pelagol Grey C
Phthalhydroquinone
Pyrocatechin
Pyrocatechine
Pyrokatechin (Czech)

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic Analysisembryo/hamster3 µmol/LMUREAV 373,113,1997
Cytogenetic Analysisovary/hamster50 mg/LCALEDQ 14,251,1981
Cytogenetic Analysisovary/hamster25 µmol/L/4HMUREAV 661,57,2009
Cytogenetic Analysislung/hamster60 µmol/L/2HMUREAV 540,29,2003
DNA Damageovary/hamster1 µmol/L/3HMUREAV 661,57,2009
DNA Damageother cell types/mouse0.25 mmol/L/3HJOETD7 155,599,2014
DNA Damagelymphocyte/human100 µmol/LEMMUEG 26,305,1995
DNA Damage/Other microorganisms10 mmol/LMUREAV 368,235,1996
DNA Damageliver/rat3 mmol/LCALEDQ 63,47,1992
DNA Damagelymphocyte/mouse500 µmol/LMUREAV 203,155,1988
DNA inhibitionlymphocyte/mouse250 µmol/LMOPMA3 28,560,1985
DNA inhibitionHeLa cell/human200 µmol/LMUREAV 92,427,1982
DNA repair/Bacillus subtilis500 mg/LESKGA2 32,171,1986
gene conversion and mitotic recombination/Saccharomyes cerevisiae300 mg/LMUREAV 135,109,1984
gene conversion and mitotic recombination/Aspergillus nidulans10 mmol/LMUTAEX 2,235,1987
micronucleus testoral/mouse40 mg/kgMUREAV 208,61,1988
micronucleus testintraperitoneal/mouse10 mg/kgMUREAV 341,29,1994
micronucleus testlung/hamster156 µmol/L/6H (+enzymatic activation step)MUTAEX 26,709,2011
micronucleus testlung/hamster78 µmol/L/6H (-enzymatic activation step)MUTAEX 26,709,2011
micronucleus testlung/hamster20 µmol/L/24H (-enzymatic activation step)MUTAEX 26,709,2011
micronucleus testlung/hamster4.7 µmol/L/48H (-enzymatic activation step)MUTAEX 26,709,2011
micronucleus testovary/hamster22.2 µmol/L/24H (-enzymatic activation step)MUREAV 751,1,2013
micronucleus testovary/hamster200 µmol/L/3H (+enzymatic activation step)MUREAV 751,1,2013
micronucleus testfibroblast/hamster20 µmol/L/48HMUREAV 770,37,2014
micronucleus testlung/hamster10 µmol/L/12HMUREAV 808,27,2016
micronucleus testlung/hamster25 µmol/LEVHPAZ 82,81,1989
micronucleus testlung/hamster20 µmol/L/6HMUREAV 808,27,2016
micronucleus testovary/hamster10 µmol/L/4HMUREAV 661,57,2009
morphological transformother cell types/mouse0.25 mg/L/12DMUREAV 557,191,2004
morphological transformembryo/hamster1 µmol/LMUREAV 373,113,1997
mutation in mammalian somatic cellsembryo/hamster10 µmol/LMUREAV 373,113,1997
mutation in mammalian somatic cellslymphocyte/mouse2500 µg/LEMMUEG 11,523,1988
mutation in microorganisms/Salmonella typhimurium15 µmol/plate (+enzymatic activation step)PAACA3 20,117,1979
mutation in microorganisms/Salmonella typhimurium4 µg/plate (-enzymatic activation step)ABCHA6 45,327,1981
mutation in microorganisms/Escherichia coli2 mg/plate (-enzymatic activation step)MUREAV 467,41,2000
mutation in microorganisms/Saccharomyes cerevisiae599 mg/L/16HMUTAEX 20,105,2004
other mutation test systemslymphocyte/human40 µmol/LCNREA8 40,1189,1980
other mutation test systemsbone marrow/rabbit2 mmol/LAJIMD8 7,485,1985
sex chromosome loss and nondisjunctionembryo/hamster30 µmol/LMUREAV 373,113,1997
sister chromatid exchangelung/hamster12500 nmol/LEVHPAZ 82,81,1989
sister chromatid exchangeembryo/hamster10 µmol/LMUREAV 373,113,1997
sister chromatid exchangelymphocyte/human40 µmol/LCNREA8 40,1189,1980
Unscheduled DNA Synthesisoral/rat1 gm/kgJJIND8 74,1283,1985
Unscheduled DNA Synthesisembryo/hamster1 µmol/LMUREAV 373,113,1997

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
oral/rat 1 gm/kg (11D pregnant)Reproductive: Effects on fertility: Litter size (e.g., # fetuses per litter; measured before birth)TJADAB 41,43,1990
subcutaneous/rat 5 mg/kg (1D prior to copulation)Reproductive: Maternal effects: Ovaries, fallopian tubesENDOAO 57,466,1955

Tumorigenic Data and References

Route/OrganismDoseEffectReference
oral/mouse lowest published toxic dose: 645 gm/kg/96W- continuousTumorigenic: Carcinogenic by RTECS criteria

Gastrointestinal: Tumors
JJCREP 81,207,1990
oral/mouse lowest published toxic dose: 3696 mg/kg/44W- continuousTumorigenic: Neoplastic by RTECS criteria

Tumorigenic: Facilitates action of known carcinogens

Gastrointestinal: Tumors
CALEDQ 139,167,1999
oral/rat lowest published toxic dose: 7854 mg/kg/34W- intermittentTumorigenic: Neoplastic by RTECS criteria

Gastrointestinal: Tumors
JTPAE7 29,180,2001
oral/rat lowest published toxic dose: 102648 mg/kg/104W- intermittentTumorigenic: Carcinogenic by RTECS criteria

Gastrointestinal: Tumors
JTPAE7 29,180,2001
oral/rat lowest published toxic dose: 437 gm/kg/2Y- continuousTumorigenic: Carcinogenic by RTECS criteria

Gastrointestinal: Tumors
JJCREP 81,207,1990
oral/rat toxic dose: 60640 mg/kg/24W- continuousTumorigenic: Neoplastic by RTECS criteria

Gastrointestinal: Tumors
JJCREP 77,854,1986
oral/rat toxic dose: 349 gm/kg/2Y- continuousTumorigenic: Carcinogenic by RTECS criteria

Gastrointestinal: Tumors
FCTOD7 33,93,1995
oral/rat lowest published toxic dose: 171 gm/kg/51W- continuousTumorigenic: Carcinogenic by RTECS criteria

Gastrointestinal: Tumors
JJCREP 85,17,1994

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, endothelium Inhibitor Concentration Low: 10 µmol/L/30MIn Vitro Toxicity Studies: Other assaysPYTOEY 19,245,2012
In Vitro/Human, erythrocytes Inhibitor Concentration Low: 100 mg/L/1HIn Vitro Toxicity Studies: Hemolysis in vitro

In Vitro Toxicity Studies: Other assays
FCTOD7 49,2202,2011
In Vitro/Human, melanoma Inhibitor Concentration Low: 100 mg/L/1HBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: CatalasesFCTOD7 50,2123,2012
In Vitro/jzxInhibitor Concentration Low: 150 µmol/L/24HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.

In Vitro Toxicity Studies: Apoptosis in vitro

In Vitro Toxicity Studies: Other assays
TXCYAC 271,107,2010
In Vitro/Rat, endocrine tumor Inhibitor Concentration Low: 5.32 µmol/LBiochemical: Neurotransmitters or modulators (putative): Dopamine at other sitesFCTOD7 50,390,2012
intraperitoneal/guinea pig lowest published lethal dose: 150 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
intraperitoneal/guinea pig lowest published lethal dose: 150 mg/kgHBTXAC 1,62,1955
intraperitoneal/mouse lethal dose (50 percent kill): 68 mg/kgPHTOEH 64,247,1989
intraperitoneal/mouse lethal dose (50 percent kill): 190 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
intravenous/cat lowest published lethal dose: 100 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
intravenous/Dog lowest published lethal dose: 40 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
intravenous/Dog lowest published lethal dose: 40 mg/kgHBTXAC 1,62,1955
oral/cat lethal dose (50 percent kill): 100 mg/kgIPSTB3 3,93,1976
oral/Dog lethal dose (50 percent kill): 130 mg/kgIPSTB3 3,93,1976
oral/Dog lowest published lethal dose: 130 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
oral/guinea pig lethal dose (50 percent kill): 210 mg/kgAFREAW 3,197,1951
oral/mammal (species unspecified) lethal dose (50 percent kill): 240 mg/kgBehavioral: Change in motor activity (specific assay)

Behavioral: Muscle contraction or spasticity

Lung, Thorax, or Respiration: Dyspnea
TPKVAL 15,136,1979
oral/mouse lethal dose (50 percent kill): 100 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
oral/mouse lethal dose (50 percent kill): 260 mg/kgAFREAW 3,197,1951
oral/rabbit lowest published lethal dose: 200 mg/kgBehavioral: Altered sleep time (including change in righting reflex)

Blood: Luekopenia

Blood: Methemoglobinemia- Carboxhemoglobinemia
38MKAJ 2A,2585,1981
oral/rabbit lowest published lethal dose: 1000 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
oral/rat lethal dose (50 percent kill): 3890 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
oral/rat lowest published toxic dose: 48 mg/kgPeripheral Nerve and Sensation: Recording from peripheral motor nerveTPKVAL 15,136,1979
oral/rat lethal dose (50 percent kill): 260 mg/kgAFREAW 3,197,1951
parenteral/frog lowest published lethal dose: 160 mg/kgPeripheral Nerve and Sensation: Spastic paralysis with/without sensory change

Behavioral: Convulsions or effect on seizure threshold
AEPPAE 166,437,1932
skin/rabbit lethal dose (50 percent kill): 800 mg/kgSkin: After topical application: Primary irritation

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
AIHAAP 37,596,1976
skin/rabbit lethal dose (50 percent kill): 800 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
subcutaneous/frog lowest published lethal dose: 160 mg/kgHBTXAC 1,62,1955
subcutaneous/guinea pig lowest published lethal dose: 200 mg/kgHBTXAC 1,62,1955
subcutaneous/guinea pig lowest published lethal dose: 200 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
subcutaneous/mouse lethal dose (50 percent kill): 247 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994
subcutaneous/mouse lethal dose (50 percent kill): 247 mg/kgINHEAO 5,143,1967
subcutaneous/rabbit lowest published lethal dose: 225 mg/kgJAFCAU 17,497,1969
subcutaneous/rat lowest published lethal dose: 110 mg/kgAIPTAK 176,193,1968
subcutaneous/rat lowest published lethal dose: 200 mg/kgBehavioral: Ataxia

Behavioral: Tetany

Lung, Thorax, or Respiration: Dyspnea
VCVGK* -,224,1994

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
intraperitoneal/mouse lowest published toxic dose: 450 mg/kg/3D- intermittentBlood: Changes in bone marrow not included in above

Blood: Changes in spleen
VCVGK* -,225,1994
intravenous/mouse lowest published toxic dose: 450 mg/kg/3D- intermittentBlood: Changes in bone marrow not included in above

Blood: Changes in spleen
VCVGK* -,225,1994
oral/chicken lowest published toxic dose: 98 gm/kg/4W- intermittentRelated to Chronic Data: Death in the "MULTIPLE DOSE" data type fieldFEPRA7 29,568,1970
oral/rat lowest published toxic dose: 15470 mg/kg/34W- intermittentBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)JTPAE7 29,180,2001
oral/rat lowest published toxic dose: 2226 mg/kg/7D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainJTPAE7 29,180,2001
oral/rat lowest published toxic dose: 360 mg/kg/5D- intermittentBiochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other oxidoreductases

Biochemical: Metabolism (intermediary): Lipids including transport
PHREP* 57,70,2005

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 5 ppm (skin)DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Confirmed animal carcinogenDTLVS* TLV/BEI,2013
International Agency for Research on Cancer (IARC)Cancer Review:Animal Sufficient EvidenceIMEMDT 71,433,1999
International Agency for Research on Cancer (IARC)Cancer Review:Animal Inadequate EvidenceIMEMDT 15,155,1977
International Agency for Research on Cancer (IARC)Cancer Review:Human No Adequate DataIMEMDT 15,155,1977
International Agency for Research on Cancer (IARC)Cancer Review:Human No Adequate DataIMEMDT 71,433,1999
International Agency for Research on Cancer (IARC)Cancer Review:Group 2BIMEMDT 71,433,1999
TOXICOLOGY REVIEWMUREAV 47,75,1978
TOXICOLOGY REVIEWMUREAV 566,99,2004
TOXICOLOGY REVIEWMUREAV 567,227,2004
TOXICOLOGY REVIEWMUREAV 567,109,2004
TOXICOLOGY REVIEWMUREAV 567,151,2004
TOXICOLOGY REVIEWMUREAV 627,10,2007
TOXICOLOGY REVIEWMUREAV 584,1,2005
TOXICOLOGY REVIEWBCLPT* 96,131,2005
TOXICOLOGY REVIEWMUREAV 682,94,2009
TOXICOLOGY REVIEWMUTAEX 23,271,2008
TOXICOLOGY REVIEWFITOT* 82,513,2011
TOXICOLOGY REVIEWMUREAV 721,27,2011
TOXICOLOGY REVIEWFCTOD7 55,596,2013
TOXICOLOGY REVIEWEMMUEG 55,679,2014
TOXICOLOGY REVIEWMUREAV 802,1,2016
TOXICOLOGY REVIEWFCTOD7 94,93,2016
TOXICOLOGY REVIEWRTOPDW 55,43,2009

Standards and Regulations

OrganizationStandardReference
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 5 ppm (23 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 4.5 ppm (20 mg/m3);KZW 9 ppm (40 mg/m3), inhal, skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 5 ppm (23 mg/m3), Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 5 ppm (20 mg/m3), carc, MAY2011
Occupational Exposure Limit-FINLANDtime-weighted average 5 ppm (22 mg/m3), short term exposure limit 10 ppm (45 mg/m3), skin, NOV2011
Occupational Exposure Limit-FRANCEVME 5 ppm (20 mg/m3), FEB2006
Occupational Exposure Limit-ICELANDtime-weighted average 5 ppm (20 mg/m3), NOV2011
Occupational Exposure Limit-JAPAN2B carc, MAY2012
Occupational Exposure Limit-KOREAtime-weighted average 5 ppm (20 mg/m3), 2006
Occupational Exposure Limit-MEXICOtime-weighted average 5 ppm (20 mg/m3) (skin), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 5 ppm (23 mg/m3), skin, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 5 ppm (20 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 5 ppm (23 mg/m3), JUL2005
Occupational Exposure Limit-RUSSIAshort term exposure limit 0.5 mg/m3, Skin, JUN2003
Occupational Exposure Limit-SWEDENtime-weighted average 5 ppm (20 mg/m3);short term exposure limit 10 ppm (40 mg/m3), Skin, JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 5 ppm (23 mg/m3), inhal, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 20 mg/m3, 2003
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 5 ppm (23 mg/m3), OCT2007

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO CATECHOL-air10H time-weighted average 5 ppm (Sk)NIOSH* DHHS #95-121,1995
National Occupational Exposure Survey 1983Hazard Code M1763; Number of Industries 8; Total Number of Facilities 700; Number of Occupations 15; Total Number of Employees Exposed 13516; Total Number of Female Employees Exposed 5799
National Occupational Hazard Survey 1974Hazard Code M1763; Number of Industries 4; Total Number of Facilities 147; Number of Occupations 6; Total Number of Employees Exposed 642

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
On EPA IRIS database
Page last reviewed: November 16, 2018