In most cases, recovery occurs in a few days. Contact of the eyes with concentrated solutions of this substance can cause severe damage and possible blindness. Inhalation can cause headache, coughing, dizziness, lung damage, and difficult breathing and may be fatal. Contact of the vapor with skin can cause dermatitis, and direct contact with the solid can lead to severe irritation and burns. Exposure to osmium tetroxide via inhalation, skin contact, or ingestion can lead to systemic toxic effects involving liver and kidney damage.
Osmium tetroxide is regarded as a substance with poor warning properties.
Chronic exposure to osmium tetroxide can result in an accumulation of osmium compounds in the liver and kidney and damage to these organs. Flammability and Explosibility Noncombustible Reactivity and Incompatibility Osmium tetroxide reacts with hydrochloric acid to form chlorine gas. 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. In the event of skin contact, immediately wash with soap and water and remove contaminated clothing.