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Pyridine

RTECS #
UR8400000
CAS #
110-86-1
See: NMAM or OSHA Methods
Updated
December 2018
Molecular Weight
79.11
Molecular Formula
C5H5N
Synonyms
Azabenzene
Azine
NCI-C55301
Piridina (Italian)
Pirydyna (Polish)
Pyridin (German)
Pyridine (ACGIH:OSHA)
RCRA waste number U196

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
skin /rabbit 500 mg/24H mild85JCAE -,839,1986

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
mutation in microorganisms/Salmonella typhimurium6 mmol/L/2H (-enzymatic activation step)CNREA8 39,4152,1979
mutation in microorganisms/Salmonella typhimurium6 mmol/L/48HHPV361 -,-,2003
sex chromosome loss and nondisjunction/Saccharomyes cerevisiae10900 ppmMUREAV 163,23,1986
Unscheduled DNA Synthesisoral/mouse700 mg/kgJJATDK 20,389,2000

Tumorigenic Data and References

Route/OrganismDoseEffectReference
oral/mouse lowest published toxic dose: 25480 mg/kg/2Y- continuousTumorigenic: Carcinogenic by RTECS criteria

Liver: Tumors
NTPTR* NTP-TR-470,2000
oral/mouse lowest published toxic dose: 25480 mg/kg/104W- continuousTumorigenic: Carcinogenic by RTECS criteria

Liver: Tumors
NTIS** PB2000-106687
oral/mouse lowest published toxic dose: 11025 mg/kg/105W- continuousTumorigenic: Carcinogenic by RTECS criteria

Liver: Tumors
NTIS** PB2000-106687
oral/rat lowest published toxic dose: 24024 mg/kg/2Y- continuousTumorigenic: Neoplastic by RTECS criteria

Kidney, Ureter, and Bladder: Bladder tumors
NTPTR* NTP-TR-470,2000
oral/rat lowest published toxic dose: 17472 mg/kg/104W- continuousTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Kidney, Ureter, and Bladder: Kidney tumors
NTIS** PB2000-106687
oral/rat lowest published toxic dose: 7350 mg/kg/105W- continuousTumorigenic: Carcinogenic by RTECS criteria

Blood: Leukemia
NTIS** PB2000-106687
oral/rat lowest published toxic dose: 26208 mg/kg/104W- continuousTumorigenic: Neoplastic by RTECS criteria

Reproductive: Tumorigenic effects: Testicular tumors
NTIS** PB2000-106687

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, leukemia cells Inhibitor Concentration (25 percent kill): 4166.7 mg/L/24HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.TIVIEQ 26,1150,2012
In Vitro/Human, leukemia cells Inhibitor Concentration (50 percent kill): 2370 mg/L/24HIn Vitro Toxicity Studies: Other assaysTIVIEQ 26,1150,2012
In Vitro/Human, lymphocyte Inhibitor Concentration (30 percent kill): >200 mg/L/45HIn Vitro Toxicity Studies: Cell viability (dye exclusion): trypan blue assay etc.TIVIEQ 29,901,2015
In Vitro/Human, lymphocyte Inhibitor Concentration (50 percent kill): >200 mg/L/45HIn Vitro Toxicity Studies: Other assaysTIVIEQ 29,901,2015
In Vitro/Human, monocyte Inhibitor Concentration Low: 5000 mg/L/2HIn Vitro Toxicity Studies: Other assaysTIVIEQ 27,1233,2013
In Vitro/Rabbit, ocular Inhibitor Concentration Low: 5 pph/5MIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 27,1855,2013
inhalation/mammal (species unspecified) lethal concentration (50 percent kill): 10 gm/m3GTPZAB 32(10),25,1988
inhalation/rat lethal concentration (50 percent kill): 9010 ppm/1HHPV361 -,-,2003
inhalation/rat Lowest published lethal concentration: 4900 ppm/4HBehavioral: Somnolence (general depressed activity)

Lung, Thorax, or Respiration: Respiratory depression

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
HPV361 -,-,2003
intraperitoneal/guinea pig lowest published lethal dose: 870 mg/kgBehavioral: General anesthetic

Behavioral: Tremor

Lung, Thorax, or Respiration: Other changes
JPHYA7 17,272,1894
intraperitoneal/mouse lethal dose (50 percent kill): 950 mg/kgPBPHAW 1,542,1965
intraperitoneal/rabbit lowest published lethal dose: 15 mg/kgPeripheral Nerve and Sensation: Flaccid paralysis without anesthesia (usually neuromuscular blockage)

Behavioral: General anesthetic
JIDIAQ 42,473,1928
intraperitoneal/rat lethal dose (50 percent kill): 866 mg/kgNTIS** PB195-158
intravenous/Dog lethal dose (50 percent kill): 880 mg/kgCardiac: Change in rate

Vascular: BP lowering not characterized in autonomic section

Lung, Thorax, or Respiration: Respiratory depression
TXCYAC 4,165,1975
intravenous/mouse lethal dose (50 percent kill): 420 mg/kgBehavioral: Sleep

Behavioral: Somnolence (general depressed activity)

Lung, Thorax, or Respiration: Dyspnea
PLRCAT 5,341,1973
intravenous/rat lethal dose (50 percent kill): 360 mg/kgBehavioral: Sleep

Behavioral: Somnolence (general depressed activity)

Lung, Thorax, or Respiration: Dyspnea
PLRCAT 5,341,1973
oral/guinea pig lowest published lethal dose: 4 gm/kgBehavioral: General anesthetic

Behavioral: Tremor

Lung, Thorax, or Respiration: Other changes
JPHYA7 17,272,1894
oral/mammal (species unspecified) lethal dose (50 percent kill): 1500 mg/kgGTPZAB 32(10),25,1988
oral/mouse lowest published toxic dose: 500 mg/kgBehavioral: Somnolence (general depressed activity)

Behavioral: Coma
JJATDK 20,389,2000
oral/mouse lowest published lethal dose: 1000 mg/kgLiver: Hepatitis (hepatocellular necrosis), diffuse

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Transaminases
JJATDK 20,389,2000
oral/mouse lethal dose (50 percent kill): 1500 mg/kgBehavioral: Sleep

Behavioral: Somnolence (general depressed activity)

Lung, Thorax, or Respiration: Dyspnea
PLRCAT 5,341,1973
parenteral/frog lowest published lethal dose: 870 mg/kg85IXA4 -,695,1948
skin/guinea pig lethal dose (50 percent kill): 1 gm/kg85JCAE -,839,1986
skin/rabbit lowest published lethal dose: 2000 mg/kgSkin: After topical application: Primary irritationHPV361 -,-,2003
subcutaneous/mouse lethal dose (50 percent kill): 1250 mg/kgBehavioral: Sleep

Behavioral: Somnolence (general depressed activity)

Lung, Thorax, or Respiration: Dyspnea
PLRCAT 5,341,1973
subcutaneous/rabbit lowest published lethal dose: 800 mg/kg85IXA4 -,695,1948
subcutaneous/rat lethal dose (50 percent kill): 866 mg/kgCTOXAO 4,185,1971

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/rat lowest published toxic concentration: 1 mg/m3/24H/60D- continuousBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase

Biochemical: Metabolism (intermediary): Other proteins
GISAAA 31(11),3,1966
inhalation/rat lowest published toxic concentration: 5 ppm/4D- continuousOlfaction: Other olfaction effectsHPV361 -,,2003
intraperitoneal/mouse lowest published toxic dose: 500 mg/kg/5D- intermittentBrain and Coverings: Other degenerative changes

Cardiac: Other changes

Biochemical: Metabolism (intermediary): Lipids including transport
CRTOEC 21,583,2008
intraperitoneal/rat lowest published toxic dose: 494 mg/kg/5D- intermittentBlood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other enzymes
TOLED5 85,173,1996
intraperitoneal/rat lowest published toxic dose: 1329 ng/kg/3D- intermittentLiver: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Cytochrome oxidases (indlucing oxidative phosphrylation)
TOLED5 144,55,2003
oral/mouse lowest published toxic dose: 420 mg/kg/13W- continuousLiver: Changes in liver weightNTPTR* NTP-TR-470,2000
oral/mouse lowest published toxic dose: 2275 mg/kg/13W- continuousNutritional and Gross Metabolic: Weight loss or decreased weight gainHPV361 -,,2003
oral/mouse lowest published toxic dose: 11200 mg/kg/8W- continuousLiver: Fatty liver degeneration

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
HPV361 -,,2003
oral/rat lowest published toxic dose: 812.5 mg/kg/13W- continuousNutritional and Gross Metabolic: Weight loss or decreased weight gainHPV361 -,,2003
oral/rat lowest published toxic dose: 4000 mg/kg/8W- continuousLiver: Hepatitis (hepatocellular necrosis), diffuse

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
HPV361 -,,2003
oral/rat lowest published toxic dose: 5768 mg/kg/103W- continuousNutritional and Gross Metabolic: Weight loss or decreased weight gainHPV361 -,,2003
oral/rat lowest published toxic dose: 12257 mg/kg/103W- continuousLiver: 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
HPV361 -,,2003
oral/rat lowest published toxic dose: 890 mg/kg/89D- continuousNutritional and Gross Metabolic: Weight loss or decreased weight gainHPV361 -,,2003
oral/rat lowest published toxic dose: 2225 mg/kg/89D- continuousLiver: Changes in liver weight

Blood: Changes in serum composition (e.g. TP, bilirubin, cholesterol)

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
HPV361 -,,2003
oral/rat lowest published toxic dose: 25 mg/kg/14W- intermittentBlood: Change in clotting factors

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
GISAAA 23(7),30,1958

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 1 ppmDTLVS* 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 Limited EvidenceIMEMDT 77,564,2000
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 77,564,2000
International Agency for Research on Cancer (IARC)Cancer Review:Group 3IMEMDT 77,564,2000
TOXICOLOGY REVIEWPAREAQ 4,1,1952
TOXICOLOGY REVIEWEMMUEG 39,69,2002
TOXICOLOGY REVIEWMUREAV 543,201,2003
TOXICOLOGY REVIEWMUREAV 584,1,2005
TOXICOLOGY REVIEWMUREAV 654,114,2008
TOXICOLOGY REVIEWMUREAV 566,49,2004
TOXICOLOGY REVIEWMUREAV 653,99,2008
TOXICOLOGY REVIEWFCTOD7 55,596,2013
TOXICOLOGY REVIEWMUREAV 795,7,2016
TOXICOLOGY REVIEWFCTOD7 94,93,2016
TOXICOLOGY REVIEWRTOPDW 55,43,2009
TOXICOLOGY REVIEWRTOPDW 56,54,2010
TOXICOLOGY REVIEWRTOPDW 59,364,2011

Standards and Regulations

OrganizationStandardReference
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 5 ppm (15 mg/m3)DTLVS* 3,220,1971
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 5 ppm (15 mg/m3), JAN1993
Occupational Exposure Limit-AUSTRALIAtime-weighted average 5 ppm (16 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 5 ppm (15 mg/m3);KZW 20 ppm (60 mg/m3), skin, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 5 ppm (16 mg/m3), MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 5 ppm (15 mg/m3), MAY2011
Occupational Exposure Limit-FRANCEVME 5 ppm (15 mg/m3), VLE 10 ppm (30 mg/m3), FEB2006
Occupational Exposure Limit-HUNGARYtime-weighted average 15 mg/m3, short term exposure limit 60 mg/m3, Skin, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 5 ppm (15 mg/m3), NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 5 ppm (15 mg/m3), 2006
Occupational Exposure Limit-MEXICOtime-weighted average 5 ppm (15 mg/m3);short term exposure limit 10 ppm (30 mg/m3), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 5 ppm (16 mg/m3), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 5 ppm (15 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 5 ppm (16 mg/m3), JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 5 mg/m3, MAC(short term exposure limit) 30 mg/me, JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 5 mg/m3, JUN2003
Occupational Exposure Limit-SWEDENtime-weighted average 2 ppm (7 mg/m3);short term exposure limit 3 ppm (10 mg/m3), JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 5 ppm (15 mg/m3), KZG-week 10 ppm (30 mg/m3), JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 0.9 mg/m3, 2003
Occupational Exposure Limit-THE PHILIPPINEStime-weighted average 5 mg/m3, JAN1993
Occupational Exposure Limit-TURKEYtime-weighted average 5 ppm (15 mg/m3), JAN1993
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 5 ppm (16 mg/m3);short term exposure limit 10 ppm (33 mg/m3), OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 5 ppm (15 mg/m3)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)8H time-weighted average 5 ppm (15 mg/m3)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 5 ppm (15 mg/m3)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 5 ppm (15 mg/m3)CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO PYRIDINE-air10H time-weighted average 5 ppmNIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code 65080; Number of Industries 32; Total Number of Facilities 1558; Number of Occupations 42; Total Number of Employees Exposed 42908; Total Number of Female Employees Exposed 10568
National Occupational Hazard Survey 1974Hazard Code 65080; Number of Industries 22; Total Number of Facilities 1103; Number of Occupations 18; Total Number of Employees Exposed 29286

Status in Federal Agencies

OrganizationReference
ATSDR TOXICOLOGY PROFILE (NTIS** PB/93/110831/AS)
EPA GENETOX PROGRAM 1988, Positive/dose response: In vitro SCE-nonhuman
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 (water);clear evidence:mouse
NCI Carcinogenesis Studies (water);equivocal evidence:rat
NIOSH Analytical Method, 1994: Pyridine, 1613
NIOSH Analytical Method, 1996: Pyridine, 1613
NTP Carcinogenesis studies (drinking water);some evidence:rat NTPTR* NTP-TR-470,2000
On EPA IRIS database
Page last reviewed: November 16, 2018