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Nitrogen monoxide

RTECS #
QX0525000
CAS #
10102-43-9; 51005-21-1; 90452-29-2; 90880-94-7
See: NMAM or OSHA Methods
Updated
March 2019
Molecular Weight
30.01
Molecular Formula
NO
Synonyms
Amidogen, oxo-
Bioxyde d'azote (French)
Nitric oxide
Nitric oxide (ACGIH:OSHA)
Nitric oxide trimer
Nitrosyl radical
Oxyde nitrique (French)
RCRA waste number P076
Stickmonoxyd (German)

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
mutation in mammalian somatic cellsinhalation/rat27 ppm/3H-continuousMUREAV 136,119,1984
mutation in mammalian somatic cellsfibroblast/hamster10 ppmMUREAV 136,119,1984
mutation in microorganisms/Salmonella typhimurium30 ppm (+enzymatic activation step)MUREAV 136,119,1984

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/Dog Lowest published lethal concentration: 5000 ppm/25MLung, Thorax, or Respiration: Acute pulmonary edema

Blood: Methemoglobinemia- Carboxhemoglobinemia
BJANAD 39,393,1967
inhalation/Dog lowest published toxic concentration: 20 ppm/6HLung, Thorax, or Respiration: Other changesCYLPDN 23,278,2002
inhalation/human lowest published toxic concentration: 76 mg/m3Behavioral: Muscle weaknessVCVN5* -,32,1993
inhalation/mouse Lowest published lethal concentration: 320 ppmBehavioral: Convulsions or effect on seizure threshold

Lung, Thorax, or Respiration: Cyanosis

Blood: Methemoglobinemia- Carboxhemoglobinemia
AEPPAE 181,145,1936
inhalation/mouse lowest published toxic concentration: 6000 mg/m3/4MBehavioral: Alteration of classical conditioningVCVN5* -,32,1993
inhalation/mouse Lowest published lethal concentration: 6000 mg/m3/6MVCVN5* -,32,1993
inhalation/mouse lowest published toxic concentration: 3000 mg/m3/6MBehavioral: Alteration of classical conditioningVCVN5* -,32,1993
inhalation/mouse Lowest published lethal concentration: 3000 mg/m3/12MVCVN5* -,32,1993
inhalation/mouse Lowest published lethal concentration: 320 ppm/1HTXCYAC 208,177,2005
inhalation/rabbit Lowest published lethal concentration: 315 ppm/15MTXCYAC 208,177,2005
inhalation/rabbit lowest published toxic concentration: 90 ppm/8HEye: Corneal damageTXCYAC 208,177,2005
inhalation/rabbit lowest published toxic concentration: 10 pph/20MBlood: Other changes

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other enzymes
CEXPB9 27,95,2000
inhalation/rat lowest published toxic concentration: 140 mg/m3Blood: Methemoglobinemia- CarboxhemoglobinemiaVCVN5* -,32,1993
inhalation/rat lethal concentration (50 percent kill): 160 mg/m3VCVN5* -,32,1993
inhalation/rat Lowest published lethal concentration: 797 ppm/15MTXCYAC 208,177,2005
inhalation/rat lethal concentration (50 percent kill): 1068 mg/kgENTOX* -,230,2005
inhalation/rat lowest published toxic concentration: 10 ppm/5HVascular: Structural changes in vessels

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: Other enzymes
TOXID9 -,437,2009

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/infant lowest published toxic concentration: 20 ppm/5D- continuousLung, Thorax, or Respiration: Other changesNEJMAG 342,469,2000
inhalation/mammal (species unspecified) lowest published toxic concentration: 50 mg/m3/6H/7W- intermittentBlood: Normocytic anemiaVCVN5* -,33,1989
inhalation/mouse lowest published toxic concentration: 10 ppm/2H/30W- intermittentLung, Thorax, or Respiration: Emphysema

Blood: Pigmented or nucleated red blood cells

Blood: Changes in leukocyte (WBC) count
ENVRAL 19,154,1979
inhalation/rabbit lowest published toxic concentration: 14 mg/m3/24H/17W- continuousCardiac: EKG changes not diagnostic of above

Blood: Changes in erythrocyte (RBC) count
VCVN5* -,33,1989
inhalation/rat lowest published toxic concentration: 1 mg/m3/3240H-continuousLung, Thorax, or Respiration: Emphysema

Liver: Fatty liver degeneration

Kidney, Ureter, and Bladder: Changes primarily in glomeruli
VCVN5* -,33,1989
inhalation/rat lowest published toxic concentration: 14 mg/m3/24H/17W- continuousCardiac: EKG changes not diagnostic of above

Blood: Changes in erythrocyte (RBC) count
VCVN5* -,33,1989
inhalation/rat lowest published toxic concentration: 200 ppm/6H/7D- intermittentLung, Thorax, or Respiration: Acute pulmonary edema

Blood: Methemoglobinemia- Carboxhemoglobinemia
TOXID9 42,253,1998
inhalation/rat lowest published toxic concentration: 50 mg/m3/6H/7W- intermittentLung, Thorax, or Respiration: Changes in lung weight

Liver: Changes in liver weight

Nutritional and Gross Metabolic: Weight loss or decreased weight gain
GTPZAB 19(4),52,1975
inhalation/rat lowest published toxic concentration: 3 mg/m3/24H/16D- continuousBrain and Coverings: Recordings from specific areas of CNS

Blood: Methemoglobinemia- Carboxhemoglobinemia

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
GISAAA 48(9),69,1983
inhalation/rat lowest published toxic concentration: 160 ppm/6H/4W- intermittentBlood: Methemoglobinemia- CarboxhemoglobinemiaTOXID9 42,253,1998
inhalation/rat lowest published toxic concentration: 9.8 ppm/72W- intermittentLung, Thorax, or Respiration: EmphysemaTXCYAC 208,177,2005

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 25 ppmDTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWCTOXAO 7,145,1974
TOXICOLOGY REVIEWXPHBAO 272,1,1941
TOXICOLOGY REVIEWTOLED5 139,163,2003
TOXICOLOGY REVIEWTPHSDY 23,406,2002
TOXICOLOGY REVIEWTPHSDY 24,560,2003
TOXICOLOGY REVIEWTPHSDY 24,609,2003
TOXICOLOGY REVIEWTPHSDY 24,389,2003
TOXICOLOGY REVIEWENTOX* -,230,2005
TOXICOLOGY REVIEWMUREAV 533,65,2003
TOXICOLOGY REVIEWMUREAV 533,173,2003
TOXICOLOGY REVIEWMUTAEX 19,169,2004
TOXICOLOGY REVIEWMUTAEX 19,423,2004
TOXICOLOGY REVIEWPAREAQ 57,217,2005
TOXICOLOGY REVIEWMUREAV 659,15,2008
TOXICOLOGY REVIEWJTPAE7 20,77,2007
TOXICOLOGY REVIEWMUREAV 658,68,2008
TOXICOLOGY REVIEWHUTOX* -,661,1996
TOXICOLOGY REVIEWHTOPA* 1,501,2002
TOXICOLOGY REVIEWTPHSDY 29,402,2008
TOXICOLOGY REVIEWMUREAV 674,3,2009
TOXICOLOGY REVIEWMUREAV 636,144,2007
TOXICOLOGY REVIEWMUREAV 667,142,2009
TOXICOLOGY REVIEWCEXPB9 34,933,2007
TOXICOLOGY REVIEWMUREAV 704,152,2010
TOXICOLOGY REVIEWMUREAV 705,40,2010
TOXICOLOGY REVIEWMUREAV 690,3,2010
TOXICOLOGY REVIEWEMMUEG 50,68,2009
TOXICOLOGY REVIEWMUREAV 751,15,2012
TOXICOLOGY REVIEWMUREAV 751,77,2012
TOXICOLOGY REVIEWMUREAV 752,153,2012
TOXICOLOGY REVIEWMUREAV 753,131,2013
TOXICOLOGY REVIEWEMMUEG 55,231,2014
TOXICOLOGY REVIEWMUREAV 764-765,72,2014
TOXICOLOGY REVIEWMUREAV 762,76,2014
TOXICOLOGY REVIEWMUREAV 764,64,2015
TOXICOLOGY REVIEWMUREAV 733,92,2012
TOXICOLOGY REVIEWMUREAV 767,8,2016
TOXICOLOGY REVIEWFCTOD7 94,93,2016
TOXICOLOGY REVIEWMUREAV 774,46,2017
TOXICOLOGY REVIEWREPTED 73,105,2017
TOXICOLOGY REVIEWMUREAV 776,32,2018
TOXICOLOGY REVIEWTOLED5 265,106,2017
TOXICOLOGY REVIEWMUREAV 777,64,2018
TOXICOLOGY REVIEWRTOPDW 54,247,2009
TOXICOLOGY REVIEWMUREAV 778,13,2018

Standards and Regulations

OrganizationStandardReference
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 25 ppm (30 mg/m3)DTLVS* 3,182,1971
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 (31 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 25 ppm (30 mg/m3), 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 25 ppm (31 mg/m3), MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 25 ppm (30 mg/m3), MAY2011
Occupational Exposure Limit-FINLANDtime-weighted average 25 ppm (31 mg/m3), NOV2011
Occupational Exposure Limit-FRANCEVME 25 ppm (30 mg/m3), FEB2006
Occupational Exposure Limit-GERMANYMAK 0.5 ppm (0.63 mg/m3), 2011
Occupational Exposure Limit-HUNGARYtime-weighted average 30 mg/m3, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 25 ppm (30 mg/m3), NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 25 ppm (30 mg/m3), 2006
Occupational Exposure Limit-MEXICOtime-weighted average 25 ppm (30 mg/m3);short term exposure limit 35 ppm (45 mg/m3), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 25 ppm (31 mg/m3), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 25 ppm (30 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 25 ppm (31 mg/m3), JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) 5 mg/m3, MAC(short term exposure limit) 10 mg/m3, JAN1999
Occupational Exposure Limit-SWEDENtime-weighted average 25 ppm (30 mg/m3);short term exposure limit 50 ppm (60 mg/m3), JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 25 ppm (30 mg/m3), JAN2011
Occupational Exposure Limit-THAILANDtime-weighted average 25 ppm (30 mg/m3), JAN1993
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 30 mg/m3, 2003
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 25 ppm (30 mg/m3)CFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)8H time-weighted average 25 ppm (30 mg/m3)CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 25 ppm (30 mg/m3)CFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 25 ppm (30 mg/m3)CFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO NITRIC OXIDE-air10H time-weighted average 25 ppmNIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code 50745; Number of Industries 3; Total Number of Facilities 59; Number of Occupations 16; Total Number of Employees Exposed 14332; Total Number of Female Employees Exposed 6183
National Occupational Hazard Survey 1974Hazard Code 50745; Number of Industries 11; Total Number of Facilities 276; Number of Occupations 11; Total Number of Employees Exposed 1354

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
NIOSH Analytical Method, 1994: Nitric oxide and nitrogen dioxide, 6014
On EPA IRIS database
OSHA ANALYTICAL METHOD #ID-109
Page last reviewed: November 16, 2018