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Nitrogen oxide

RTECS #
QX1350000
CAS #
10024-97-2
See: NMAM or OSHA Methods
Updated
December 2018
Molecular Weight
44.02
Molecular Formula
N2O
Synonyms
Dinitrogen monoxide
Factitious air
Hyponitrous acid anhydride
Laughing gas
Nitrous oxide
Nitrous oxide (ACGIH:OSHA)

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
DNA inhibitioninhalation/human50 pph/24HLANCAO 2,339,1978
DNA inhibitioninhalation/rat75000 ppm/24HAACRAT 62,738,1983
micronucleus testinhalation/human1000 µg/L/18Y- intermittentMUREAV 581,1,2005
other mutation test systemsinhalation/rat50 pph/2D-continuousTCMUD8 8,107,1988
sex chromosome loss and nondisjunctioninhalation/Drosophila melanogaster99 pph/6M-continuousENVRAL 7,286,1974

Reproductive Effects Data and References

Route/OrganismDoseEffectReference
inhalation/rat 5 pph/4H (6-15D pregnant)Reproductive: Effects on newborn: BehavioralTJADAB 31,6B,1985
inhalation/rat 20 pph/8H (28D male)Reproductive: Paternal effects: Testes, epididymis, sperm ductANESAV 44,104,1976
inhalation/rat 50 pph/24H (8-11D pregnant)Reproductive: Specific developmental abnormalities: Central nervous system

Reproductive: Specific developmental abnormalities: Cardiovascular (circulatory) system

Reproductive: Specific developmental abnormalities: Urogenital system
NATUAS 214,146,1967
inhalation/rat 50 ppm/6H (30D male)Reproductive: Effects on newborn: Live birth index (Litter size (e.g., # fetuses per litter; measured after birth)

Reproductive: Effects on newborn: Growth statistics (e.g., reduced weight gain)
ANASAB 38,319,1983
inhalation/rat 1 pph/8H (1-21D pregnant)Reproductive: Effects on embryo or fetus: Extra embryonic structures (e.g., placenta, umbilical cord)

Reproductive: Effects on embryo or fetus: Fetal death
ANESAV 48,11,1978
inhalation/rat 50 pph/4H (14D pregnant)Reproductive: Effects on newborn: Biochemical and metabolicDPTHDL 8,43,1985
inhalation/mouse 75 pph/6H (14D pregnant)Reproductive: Effects on embryo or fetus: Cytological changes (including somatic cell genetic material)TJADAB 32,26A,1985
inhalation/mouse 5000 ppm/4H (14D pregnant)Reproductive: Effects on newborn: BehavioralNTOTDY 8,189,1986
inhalation/hamster 90 pph/24H (10D pregnant)Reproductive: Effects on fertility: Post- implantation mortality (e.g., dead and/or resorbed implants per total number of implants)CJPPA3 57,1229,1979
inhalation/hamster 95 pph/24H (7D pregnant)Reproductive: Effects on embryo or fetus: Fetotoxicity (except death, e.g., stunted fetus)CJPPA3 57,1229,1979
inhalation/rat 0.1 pph (1-19D pregnant)Reproductive: Effects on embryo or fetus: Fetal death

Reproductive: Other developmental abnormalities
VCVN5* -,31,1989
subcutaneous/rat 3 gm/kg (8D pregnant)Reproductive: Effects on fertility: Post- implantation mortality (e.g., dead and/or resorbed implants per total number of implants)

Reproductive: Other effects to embryo or fetus

Reproductive: Specific developmental abnormalities: Musculoskeletal system
TJADAB 43,151,1991
subcutaneous/rat 3 gm/kg (8D pregnant)Reproductive: Specific developmental abnormalities: Cardiovascular (circulatory) systemTJADAB 43,151,1991

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/Dog lowest published toxic concentration: 47 pph/1HBlood: Other changesAANEAB 46,699,2002
inhalation/human lowest published toxic concentration: 24 mg/kg/2HBehavioral: General anesthetic

Cardiac: Pulse rate decreased with fall in BP

Nutritional and Gross Metabolic: Body temperature decrease
BJANAD 35,631,1963
inhalation/mouse lowest published toxic concentration: 25 pph/5MBehavioral: AnalgesiaJPETAB 306,484,2003
inhalation/rat lowest published toxic concentration: 60 pph/90MNutritional and Gross Metabolic: Body temperature decreasePSCHDL 191,233,2007
inhalation/rat lowest published toxic concentration: 60 mg/m3Liver: Multiple effectsVCVN5* -,31,1993

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/hamster lowest published toxic concentration: 90 mg/m3/24H/10W- continuousLung, Thorax, or Respiration: Acute pulmonary edema

Lung, Thorax, or Respiration: Changes in lung weight

Related to Chronic Data: Death in the "MULTIPLE DOSE" data type field
VCVN5* -,31,1989
inhalation/mouse lowest published toxic concentration: 50 ppm/6H/13W- intermittentLiver: Changes in liver weight

Blood: Changes in leukocyte (WBC) count
TIHEEC 6,57,1990
inhalation/rat lowest published toxic concentration: 60 pph/90M/4D- intermittentBehavioral: TolerancePSCHDL 191,233,2007
inhalation/rat lowest published toxic concentration: 60 pph/90M/5D- intermittentBehavioral: Tolerance

Nutritional and Gross Metabolic: Body temperature increase
PSCHDL 191,233,2007
inhalation/rat lowest published toxic concentration: 60 pph/90M/5D- intermittentBehavioral: TolerancePSCHDL 191,233,2007
inhalation/woman lowest published toxic concentration: 59 ppm/5Y- intermittentPeripheral Nerve and Sensation: Sensory syndrome diagnostic of central lesionNRTXDN 26,193,2005

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 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:Animal Inadequate EvidenceIMSUDL 7,93,1987
TOXICOLOGY REVIEWCLPTAT 8,91,1967
TOXICOLOGY REVIEWAACRAT 57,328,1978
TOXICOLOGY REVIEWXPHBAO 272,1,1941
TOXICOLOGY REVIEWTPHSDY 24,55,2003
TOXICOLOGY REVIEWTPHSDY 24,609,2003
TOXICOLOGY REVIEWENTOX* -,251,2005
TOXICOLOGY REVIEWHUTOX* -,661,1996
TOXICOLOGY REVIEWHUTOX* -,577,1996
TOXICOLOGY REVIEWMUREAV 674,62,2009
TOXICOLOGY REVIEWBLREV* 3,71,1989
TOXICOLOGY REVIEWNCLNA* 16,503,1998
TOXICOLOGY REVIEWNEUCL* 23,377,2005
TOXICOLOGY REVIEWNBREV* 5,1,1981
TOXICOLOGY REVIEWPRESR* 7,123,2006
TOXICOLOGY REVIEWNTAPM* -,617,1995
TOXICOLOGY REVIEWNTAPM* -,629,1995
TOXICOLOGY REVIEWMUTAEX 26,43,2011
TOXICOLOGY REVIEWMUREAV 717,46,2011
TOXICOLOGY REVIEWNRTXDN 33,605,2012
TOXICOLOGY REVIEWMUREAV 733,21,2012
TOXICOLOGY REVIEWMUTAEX 30,459,2015
TOXICOLOGY REVIEWMUREAV 770,26,2016
TOXICOLOGY REVIEWNETEEC 60,102,2017
TOXICOLOGY REVIEWNETEEC 60,95,2017

Standards and Regulations

OrganizationStandardReference
Mine Safety and Health Administration (MSHA) STANDARDASPHYXIANTS/GASESDTLWS* 3,25,1973
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 (45 mg/m3), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 100 ppm (180 mg/m3);KZW 400 ppm (720 mg/m3), 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 50 ppm (91 mg/m3), MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 50 ppm (90 mg/m3), MAY2011
Occupational Exposure Limit-FINLANDtime-weighted average 100 ppm (180 mg/m3), NOV2011
Occupational Exposure Limit-GERMANYMAK 100 ppm (180 mg/m3), 2011
Occupational Exposure Limit-HUNGARYtime-weighted average 180 mg/m3, short term exposure limit 720 mg/m3, SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 50 ppm (90 mg/m3), NOV2011
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 25 ppm (45 mg/m3), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 100 ppm (180 mg/m3), JAN1999
Occupational Exposure Limit-PERUtime-weighted average 50 ppm (90 mg/m3), JUL2005
Occupational Exposure Limit-SWEDENtime-weighted average 100 ppm (180 mg/m3);short term exposure limit 500 ppm (900 mg/m3), JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 100 ppm (182 mg/m3), KZG-week 200 ppm (364 mg/m3), JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 152 mg/m3, 2003
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 100 ppm (183 mg/m3), OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)simple asphyxiant-inert gases and vaporsCFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)Simple asphyxiant - inert gas and vaporCFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO NITROUS OXIDE-airtime-weighted average 25 ppm for duration of exposureNIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code 51118; Number of Industries 25; Total Number of Facilities 5145; Number of Occupations 34; Total Number of Employees Exposed 112585; Total Number of Female Employees Exposed 74465
National Occupational Hazard Survey 1974Hazard Code 51118; Number of Industries 45; Total Number of Facilities 5599; Number of Occupations 36; Total Number of Employees Exposed 113333

Status in Federal Agencies

OrganizationReference
EPA GENETOX PROGRAM 1988, Inconclusive: Carcinogenicity-mouse/rat
EPA GENETOX PROGRAM 1988, Negative: Sperm morphology-mouse
EPA GENETOX PROGRAM 1988, Positive: V79 cell culture-gene mutation
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: Nitrous oxide, 6600
OSHA ANALYTICAL METHOD #ID166
Page last reviewed: November 16, 2018