Magnesium oxide, insoluble (Sintermagnesite) (respirable fraction)

The German Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area has reevaluated magnesium oxide. Magnesium oxide, sintermagnesite [1309‐48‐4], is a biopersistent granular dust. Therefore, the respirable fraction of magnesium oxide dust has been classified in Carcinogen Category 4 and a MAK value of 0.3 mg/m3 × material density was established for the respirable fraction in analogy to the other biopersistent granular dusts. Additionally for this fraction the Peak Limitation Category II with an excursion factor of 8 was established. Since magnesium oxide is not systemically distributed and accumulates only locally in the lungs, no developmental effects due to this dust are expected to occur at the MAK value of 0.3 mg/m3 × material density (respirable, R‐fraction). Magnesium oxide has accordingly been classified in Pregnancy Risk Group C. Magnesium oxide is not designated with either “Sa” or “Sh” or “H”.