Osmium oxide, caution

Caution. Carbon monooxide and osmium compounds are highly toxic. These reactions should be carried out in well ventilated fume hood. Potassium reacts violently with water care should be taken to ensure anhydrous conditions. Furthermore, potassium oxides can be explosive, so that only fresh samples with little or no surface oxide should be cut as described here. 

Caution. Osmium(VIII) oxide is extremely toxic. The yellow solid melts at 31° and has an appreciable vapor pressure even at room temperature. The compound is often liberated when solutions of osmium compounds are treated with oxidizing agents. Ample precautions to protect eyes, nose, and mouth are essential. 

Osmium melts at 3045°C. It is a hard, heavy element that is easily oxidized in air to toxic OSO4. The ease with which this oxide is formed demands caution. Osmium is difficult to work with because of its hardness at low temperatures and the possible formation of OSO4 at elevated temperatures. It is very resistant to rubbing wear, resistant to H2SO4 and 40% HF at ambient temperatures, and 36% HCl at 100°C but is easily attacked by oxygen, HNO3, and aqua regia. 

CAUTION acetone, CaCl, cacodylic acid, ethanol, glutaraldehyde, KCl, lead citrate, MgCl, NaOH, osmium tetraoxide, paraformaldehyde, propylene oxide, resins, uranyl acetate (see Appendix 4)... 

Caution. The tetraoxide of osmium, which is involved in the transport process, is more stable, volatile, and toxic than that of ruthenium. It is recommended that the operations described here, which involve the handling of the metal and the oxide at elevated temperatures, be carried out in an efficient... 

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