Osmium precautions

CAUTION This preparation involving the toxic osmium tetroxide must be carried out in a fume cupboard. For the precautions to be followed when using 30 per cent hydrogen peroxide see Section 4.2.41, p. 439. 

Orthotelluric acid, 3 145,147 Osmium compounds, nitrido, 6 204 Osmium (IV) oxide, formation of black, by ammonium hexa-bromoosmate(IV), 5 206 Osmium(VIII) oxide, precautions in using, 5 205... 

Osmium and compounds Osmium tetroxide is a colorless to pale yellow crystalline solid with an odor that has been described as pungent or chlo-rine-like. Students and workers must take precautions in the use of osmium tetroxide. Prolonged periods of inhalation exposure to osmium tetroxide cause insomnia, digestive disturbance, and distress to the pharynx and larynx. ... 

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. 

Because of its high acute toxicity, osmium tetroxide should be handled in the laboratory using the "basic prudent practices" of Chapter 5.C, supplemented by the additional precautions for work with compounds of high toxicity (Chapter 5.D). In particular, all work with osmium tetroxide should be conducted in a fume hood to prevent exposure by inhalation, and splash goggles and impermeable gloves should be worn at all times to prevent eye and skin contact. Osmium tetroxide as solid or solutions should be stored in tightly sealed containers, and these should be placed in secondary containers. 

Osmium metal and most of its compounds are probably safe to handle with proper precautions, but OSO4 and OsFg are highly toxic. The compound OSO4 is a hazard to the eyes, nose, and throat and readily oxidizes organic matter. It can cause dermatitis and ulceration of the skin on contact, as well as cause conjunctivitis, corneal irritation, halo effects, and temporary blindness. 

Caution Employ the standard precautions outlined in the introduction to this chapter for this reaction. Osmium tetraoxide, formed in situ in this reaction, is volatile and highly toxic and so an efficient hood must be used. 

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