- Selenous acid
- Monohydrated selenium dioxide
Colorless solid, transparent, colorless crystals.
As reagent for alkaloids, as oxidizing agent.
Registry Numbers and Inventories.
R 23/25 33 50/53
S 20/21 28 45 60 61
Agricultural Chemical and Pesticide; Mutagen
Japan ENCS (MITI)
Melting point, °C
Boiling point, °C
Vapor pressure, mmHg
Solubility in water
Hazards and Protection.
Store in a cool, dry place. Store in a tightly closed container. Poison room locked.
Wash thoroughly after handling. Wash hands before eating. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Do not get in eyes, on skin, or on clothing. Do not ingest or inhale. Use only in a chemical fume hood.
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Vacuum or sweep up material and place into a suitable disposal container.
Stable under normal shipping and handling conditions.
Strong reducing agents - organic materials - finely powdered metals.
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Extinguishing media: For small fires, use dry chemical, carbon dioxide, water spray or alcohol-resistant foam.
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.
When heated to decomposition it emits toxic fumes of selenium. Avoid heating.
Fire may produce irritating, corrosive and/or toxic gases.
TLV (as Se): ppm; 0.2 mg/m3 (ACGIH 1990-1991). PDK (as Se): 0.1 mg/m3 (USSR 1978).
Prolonged or repeated skin contact may cause dermatitis. May cause liver and kidney damage. May cause reproductive and fetal effects. Chronic exposure to selenium may cause central nervous system effects, digestive tract disturbances, pallor, garlic breath,
May be fatal if swallowed. May cause severe gastrointestinal tract irritation with nausea, vomiting and possible burns. May cause liver and kidney damage. May cause a garlic odor on the breath along with pallor, nervousness, depression, digestive tract disturbances and possilbe death.
May cause severe irritation of the respiratory tract with sore throat, coughing, shortness of breath and delayed lung edema.
May cause severe skin irritation. Prolonged and/or repeated contact may cause irritation and/or dermatitis.
May cause severe eye irritation. May result in corneal injury.
If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. Get medical aid immediately.
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.
I; II; III
USCG CHRIS Code