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Magnesium oxide

RTECS #
OM3850000
CAS #
1309-48-4
See: NMAM or OSHA Methods
Updated
September 2013
Molecular Weight
40.31
Molecular Formula
MgO
Synonyms
Akro-mag
Animag
Calcined brucite
Calcined magnesia
Calcined magnesite
Granmag
Magcal
Magchem 100
Maglite
Magnesia
Magnesia USTA
Magnesium oxide fume
Magnesium oxide fume (ACGIH:OSHA)
Magnezu tlenek (Polish)
Magox
Magox 85
Magox 90
Magox 95
Magox 98
Magox OP
Marmag
Oxymag
Periclase
Seawater magnesia

Tumorigenic Data and References

Route/OrganismDoseEffectReference
intratracheal/hamster lowest published toxic dose: 480 mg/kg/30W- intermittentTumorigenic: Equivocal tumorigenic agent by RTECS criteria

Olfaction: Tumors

Lung, Thorax, or Respiration: Tumors
CNREA8 33,2209,1973

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
inhalation/human lowest published toxic concentration: 400 mg/m338MKAJ 2A,1745,1981
inhalation/mammal (species unspecified) lowest published toxic concentration: 4 mg/m3/12MNutritional and Gross Metabolic: Body temperature increaseVCVN1* -,104,1988

Other Multiple Dose Data and References

Route/OrganismDoseEffectReference
inhalation/rat lowest published toxic concentration: 1120 µg/m3/24H/29D- continuousBrain and Coverings: Recordings from specific areas of CNS

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

Biochemical: Enzyme inhibition, induction, or change in blood or tissue levels: True cholinesterase
GISAAA 49(11),82,1984
inhalation/rat lowest published toxic concentration: 1000 mg/m3/4H/50D- intermittentLung, Thorax, or Respiration: Other changes

Blood: Other hemolysis with or without anemia
VCVN1* -,105,1988

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-time-weighted average 10 mg/m3 (inhal)DTLVS* TLV/BEI,2013
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-Not classifiable as a human carcinogenDTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWNBREV* 5,1,1981

Standards and Regulations

OrganizationStandardReference
Mine Safety and Health Administration (MSHA) STANDARD-airtime-weighted average 10 mg/m3 (fume)DTLVS* 3,147,1971
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 10 mg/m3, JAN1993
Occupational Exposure Limit-AUSTRALIAtime-weighted average 10 mg/m3 (fume), JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 10 mg/m3;KZW 20 mg/m3, inhal, 2007
Occupational Exposure Limit-AUSTRIAMAK-TMW 5 mg/m3;KZW 10 mg/m3, resp, 2007
Occupational Exposure Limit-AUSTRIAMAK-TMW 5 mg/m3;KZW 20 mg/m3, smoke, 2007
Occupational Exposure Limit-BELGIUMtime-weighted average 10 mg/m3 (fume), MAR2002
Occupational Exposure Limit-DENMARKtime-weighted average 6 mg(Mg)/m3, MAY2011
Occupational Exposure Limit-FRANCEVME 10 mg/m3 (fume), FEB2006
Occupational Exposure Limit-GERMANYMAK 1.5 mg/m3, resp., 2011
Occupational Exposure Limit-GERMANYMAK 4 mg/m3, inhal, 2011
Occupational Exposure Limit-HUNGARYtime-weighted average 6 mg/m3 (resp), short term exposure limit 24 mg/m3 (resp), SEP2000
Occupational Exposure Limit-ICELANDtime-weighted average 6 mg(Mg)/m3, NOV2011
Occupational Exposure Limit-KOREAtime-weighted average 10 mg/m3, 2006
Occupational Exposure Limit-MEXICOtime-weighted average 10 mg(Mg)/m3 (fume), 2004
Occupational Exposure Limit-NEW ZEALANDtime-weighted average 10 mg/m3 (fume), JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 10 mg/m3, JAN1999
Occupational Exposure Limit-PERUtime-weighted average 10 mg/m3, JUL2005
Occupational Exposure Limit-POLANDMAC(time-weighted average) dust 10 mg/m3, JAN1999
Occupational Exposure Limit-POLANDMAC(time-weighted average) fume 5 mg/m3, JAN1999
Occupational Exposure Limit-RUSSIAshort term exposure limit 4 mg/m3, JUN2003
Occupational Exposure Limit-SWITZERLANDMAK-week 3 mg/m3, fume, resp, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-TGG 10 mg/m3, 2003
Occupational Exposure Limit-TURKEYtime-weighted average 15 mg/m3, JAN1993
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 10 mg(Mg)/m3 (inhal. dust), OCT2007
Occupational Exposure Limit-UNITED KINGDOMtime-weighted average 4 mg(Mg)/m3 (fume, resp. dust), OCT2007
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Construction)8H time-weighted average 15 ppm, total particulateCFRGBR 29,1926.55,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Federal Contractors)8H time-weighted average 15 mg/m3CFRGBR 41,50-204.50,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (General Industry)8H time-weighted average 15 mg/m3, total particulateCFRGBR 29,1910.1000,1994
Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (Shipyards)8H time-weighted average 15 ppm, total particulateCFRGBR 29,1915.1000,1993

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Occupational Exposure Survey 1983Hazard Code 80298; Number of Industries 258; Total Number of Facilities 42587; Number of Occupations 177; Total Number of Employees Exposed 765812; Total Number of Female Employees Exposed 149523
National Occupational Hazard Survey 1974Hazard Code 80298; Number of Industries 201; Total Number of Facilities 28931; Number of Occupations 134; Total Number of Employees Exposed 354380

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: Elements by ICP, 7300
OSHA ANALYTICAL METHOD #ID-125G
Page last reviewed: November 16, 2018