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o-Xylene

RTECS #
ZE2450000
CAS #
95-47-6
See: NMAM or OSHA Methods
Updated
March 2019
Molecular Weight
106.18
Molecular Formula
C8H10
Synonyms
1,2-Dimethylbenzene
1,2-Xylene
o-Dimethylbenzene
o-Methyltoluene
o-Xylene (ACGIH:OSHA)
o-Xylol

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
inhalation/rat 150 mg/m3/24H (7-14D pregnant)Reproductive: Effects on embryo or fetus: Extra embryonic structures (e.g., placenta, umbilical cord)TXCYAC 18,61,1980
inhalation/rat 1500 mg/m3/24H (7-14D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)TXCYAC 18,61,1980
inhalation/rat 3000 mg/m3/24H (7-14D pregnant)Reproductive: Specific developmental abnormalities: Musculoskeletal systemTXCYAC 18,61,1980
inhalation/mouse 500 mg/m3/12H (6-15D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)

Reproductive: Specific developmental abnormalities: Musculoskeletal system
ATSUDG 8,425,1985
intraperitoneal/rat 500 mg/kg (2D male)Reproductive: Paternal effects: Spermatogenesis (including genetic material, sperm morphology, motility, and count)ARANDR 11,233,1983

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, leukemia cells Inhibitor Concentration (20 percent kill): 0.36 mmol/L/3HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.

In Vitro Toxicity Studies: Other assays
TXCYAC 271,122,2010
In Vitro/Human, leukemia cells Inhibitor Concentration (50 percent kill): 0.84 mmol/L/3HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.

In Vitro Toxicity Studies: Other assays
TXCYAC 271,122,2010
In Vitro/Human, leukemia cells Inhibitor Concentration (20 percent kill): 0.51 mmol/L/3HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TXCYAC 271,122,2010
In Vitro/Human, leukemia cells Inhibitor Concentration (50 percent kill): 1.17 mmol/L/3HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TXCYAC 271,122,2010
In Vitro/jvxInhibitor Concentration (20 percent kill): 0.37 mmol/L/3HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TXCYAC 271,122,2010
In Vitro/jvxInhibitor Concentration (50 percent kill): 1.35 mmol/L/3HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TXCYAC 271,122,2010
inhalation/human Lowest published lethal concentration: 6125 ppm/12HYAKUD5 22,883,1980
inhalation/mouse Lowest published lethal concentration: 30 gm/m3Behavioral: General anesthetic

Lung, Thorax, or Respiration: Respiratory depression

Cardiac: Other changes
AEPPAE 143,223,1929
inhalation/mouse lowest published toxic concentration: 1000 ppm/6MLung, Thorax, or Respiration: Respiratory depressionTOLED5 9,137,1981
inhalation/mouse lethal concentration (50 percent kill): 4595 ppm/6HVCVGH* -,159,1990
inhalation/rat Lowest published lethal concentration: 6125 ppm/12HJPBAA7 46,95,1938
inhalation/rat lowest published toxic concentration: 300 ppm/6HLiver: Changes in liver weight

Nutritional and Gross Metabolic: Weight loss or decreased weight gain

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Hepatic microsomal mixed oxidase (dealkylation, hydroxylation, etc.)
TOXID9 60,427,2001
intraperitoneal/mammal (species unspecified) lowest published lethal dose: 1500 mg/kgJPBAA7 46,95,1938
intraperitoneal/mouse lethal dose (50 percent kill): 1550 µL/kgARTODN 58,106,1985
oral/rat lowest published lethal dose: 5 gm/kgYAKUD5 22,883,1980
oral/rat lethal dose (50 percent kill): 3567 mg/kgVCVGH* -,160,1990
subcutaneous/mammal (species unspecified) lowest published lethal dose: 2500 mg/kgJPBAA7 46,95,1938

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/rat lowest published toxic concentration: 1800 ppm/11W- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainPHTOEH 89,6,2001
inhalation/rat lowest published toxic concentration: 3500 ppm/6H/6W- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gainVCVGH* -,162,1990
inhalation/rat lowest published toxic concentration: 1000 ppm/6H/8D- intermittentNutritional and Gross Metabolic: Weight loss or decreased weight gain

Behavioral: Food intake (animal)
FCTOD7 41,415,2003

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 100 ppm;short term exposure limit 150 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:Animal Inadequate EvidenceIMEMDT 71,1189,1999
International Agency for Research on Cancer (IARC)Cancer Review:Human Inadequate EvidenceIMEMDT 71,1189,1999
International Agency for Research on Cancer (IARC)Cancer Review:Group 3IMEMDT 71,1189,1999
TOXICOLOGY REVIEWMUREAV 47,75,1978
TOXICOLOGY REVIEWTOLED5 127,111,2002
TOXICOLOGY REVIEWENTOX* -,470,2005
TOXICOLOGY REVIEWTXAPA9 243,167,2010
TOXICOLOGY REVIEWREPTED 58,252,2015
TOXICOLOGY REVIEWRTOPDW 60,120,2011

Standards and Regulations

OrganizationStandardReference
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 100 ppm (440 mg/m3) (skin)DTLVS* 3,281,1971
Occupational Exposure Limit-AUSTRALIAtime-weighted average 80 ppm (350 mg/m3), short term exposure limit 150 ppm (655 mg/m3), JUL2008
Occupational Exposure Limit-BELGIUMtime-weighted average 50 ppm (221 mg/m3), MAR2002
Occupational Exposure Limit-BELGIUMshort term exposure limit 100 ppm (442 mg/m3), Skin, MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 25 ppm (109 mg/m3), skin, MAY2011
Occupational Exposure Limit-ECtime-weighted average 221 mg/m3 (50 ppm);short term exposure limit 442 mg/m3 (100 ppm), skin, JUN2000
Occupational Exposure Limit-FINLANDtime-weighted average 50 ppm (220 mg/m3), short term exposure limit 100 ppm (440 mg/m3), skin, NOV2011
Occupational Exposure Limit-FRANCEVME 50 ppm (221 mg/m3), VLE 100 ppm (442 mg/m3), Skin, FEB2006
Occupational Exposure Limit-HUNGARYtime-weighted average 221 mg/m3, short term exposure limit 442 mg/m3, Skin, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 25 ppm (109 mg/m3), short term exposure limit 100 ppm (442 mg/m3), skin, NOV2011
Occupational Exposure Limit-JAPANOccupational Exposure Limit 50 ppm (217 mg/m3), MAY2012
Occupational Exposure Limit-MEXICOtime-weighted average 100 ppm (435 mg/m3);short term exposure limit 150 ppm (655 mg/m3), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 50 ppm (217 mg/m3), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 25 ppm (108 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 100 ppm (434 mg/m3); short term exposure limit 150 ppm (651 mg/m3), JUL2005
Occupational Exposure Limit-SWEDENtime-weighted average 50 ppm (200 mg/m3);short term exposure limit 100 ppm (450 mg/m3), Skin, JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 100 ppm (435 mg/m3), KZG-week 200 ppm (870 mg/m3), skin, JAN2011
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 50 ppm (220 mg/m3);short term exposure limit 100 ppm (441 mg/m3), skin, OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 100 ppm (435 mg/m3)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)8H time-weighted average 100 ppm (435 mg/m3)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 100 ppm (435 mg/m3)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 100 ppm (435 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-XYLENE-air10H time-weighted average 100 ppm;short term exposure limit 150 ppmNIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code M1026; Number of Industries 30; Total Number of Facilities 2608; Number of Occupations 28; Total Number of Employees Exposed 25994; Total Number of Female Employees Exposed 5812
National Occupational Hazard Survey 1974Hazard Code M1026; Number of Industries 9; Total Number of Facilities 179; Number of Occupations 25; Total Number of Employees Exposed 5778

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
OSHA ANALYTICAL METHOD #1002
Page last reviewed: November 16, 2018