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Chemical Sampling Information (CSI)
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General Description

Synonyms: Magnesia fume; Maglite; Magox

OSHA IMIS Code Number: 1610

IMIS Name History: Magnesium Oxide Fume prior to 9/1/89

Chemical Abstracts Service (CAS) Registry Number: 1309-48-4

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: OM3850000

NIOSH Pocket Guide to Chemical Hazards, Magnesium Oxide Fume: chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

OSHA Permissible Exposure Limit (PEL):
General Industry: 29 CFR 1910.1000 Table Z-1 -- 15 mg/m3 TWA

Construction Industry: 29 CFR 1926.55 Appendix A -- 15 mg/m3 TWA

Maritime: 29 CFR 1915.1000 Table Z-Shipyards -- 15 mg/m3 TWA
American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 10 mg/m3 TWA - Inhalable fraction; see Appendix C, paragraph A; Appendix A4 - Not Classifiable as a Human Carcinogen (TLV listed under Magnesium oxide)

National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): Appendix D - Substances With No Established RELs

Health Factors

NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 750 mg/m3

Potential Symptoms: Irritation of eyes, nose; metal fume fever (4-12 hours after exposure): headache, nausea, sweating, cough, chest pain, flu-like fever; INGES.: Diarrhea

Health Effects: Lung effect (Fume fever) (HE11)

Affected Organs: Eyes, respiratory system


  1. Inhalational exposure of human volunteers to respirable magnesium oxide fume at concentrations of 110-123 mg/m3 for 45 minutes (n=3), 210 mg/m3 for 20 min. (n=1), or 230 mg/m3 for 15 min. (n=1) did not elicit symptoms of metal fume fever, affect lung function, or affect proinflammatory cytokine or cell levels in bronchoalveolar lavage fluid.
  2. Magnesium oxide is affirmed by the FDA as a generally recognized as safe (GRAS) direct food substance (21 CFR 184.1431).

Literature Basis:

  • NIOSH Pocket Guide to Chemical Hazards: Magnesium Oxide Fume.
  • International Chemical Safety Cards (WHO/IPCS/ILO): Magnesium oxide.
  • Kuschner, W.G., Wong, H., D'Alessandro, A., Quinlan, P. and Blanc, P.D.: Human pulmonary responses to experimental inhalation of high concentration fine and ultrafine magnesium oxide particles. Environ. Health Perspect. 105(11): 1234-1237, 1997.
  • Pohanish, R.P. (editor): Magnesium Oxide (Fume). In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1426-1428.

Date Last Revised: 07/21/2006

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):

  • sampling media: Tared 37-mm diameter low-ash polyvinyl chloride filter
    maximum volume: 960 Liters
    minimum volume: 480 Liters
    maximum flow rate: 2.0 L/min
    current analytical method: Gravimetric
    method reference: OSHA Analytical Method (OSHA PV2121)
    method classification: Partially Validated
    note: OSHA personnel can obtain tared sampling media from the Salt Lake Technical Center.
    note: If the net weight of the sample yields a concentration below the standard for the substance, the Salt Lake Technical Center will perform no further work on that sample. If the net weight corresponds to an amount greater than the standard, the sample may be analyzed for the appropriate element and the result reported as the substance.
    current elemental analysis method: Atomic Absorption Spectroscopy; AAS
    method reference: OSHA Analytical Method (OSHA ID-121)
    method classification: Validated
    note: An elemental analysis is performed for total magnesium and reported as the compound.

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