International Chemical Safety Cards SELENIOUS ACID ICSC: 0945 Monohydrated selenium dioxide Selenous acid H2SeO3 Molecular mass: 129.0 ICSC #    0945 CAS #     7783-00-8 RTECS # VS7175000 UN #        3283 EC #         034-002-00-8 October 03, 2000 Peer reviewed TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Not combustible. Gives off irritating or toxic fumes (or gases) in a fire. In case of fire in the surroundings: all extinguishing agents allowed. EXPLOSION EXPOSURE PREVENT DISPERSION OF DUST! STRICT HYGIENE!  •INHALATION Burning sensation. Cough. Laboured breathing. Sore throat. Shortness of breath. Symptoms may be delayed (see Notes). Ventilation, local exhaust, or breathing protection. Fresh air, rest. Half-upright position. Artificial respiration if indicated. Refer for medical attention.  •SKIN Redness. Pain. Blisters. Skin burns. Protective gloves. Protective clothing. Remove contaminated clothes. Rinse skin with plenty of water or shower. Refer for medical attention.  •EYES Redness. Pain. Severe deep burns. Face shield, or eye protection in combination with breathing protection. First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then take to a doctor.  •INGESTION Abdominal pain. Burning sensation. Sore throat. Diarrhoea. Nausea. Vomiting. Shock or collapse. Do not eat, drink, or smoke during work. Wash hands before eating. Rinse mouth. Do NOT induce vomiting. Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Evacuate danger area! Consult an expert! Cover the spilled material with dry lime or soda ash. Carefully collect remainder, then remove to safe place. (Extra personal protection: complete protective clothing including self-contained breathing apparatus). Separated from food and feedstuffs . Dry. Keep in a well-ventilated room. Note: A T symbol N symbol R: 23/25-33-50/53 S: 1/2-20/21-28-45-60-61 UN Hazard Class: 6.1 UN Packing Group: II SEE IMPORTANT INFORMATION ON BACK ICSC: 0945 Prepared in the context of cooperation between the International Programme on Chemical Safety & the Commission of the European Communities (C) IPCS CEC 1994. No modifications to the International version have been made except to add the OSHA PELs, NIOSH RELs and NIOSH IDLH values.

International Chemical Safety Cards SELENIOUS ACID ICSC: 0945 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: COLOURLESS , HYGROSCOPIC CRYSTALS PHYSICAL DANGERS: CHEMICAL DANGERS: The substance decomposes on heating producing toxic fumes of selenium dioxide. OCCUPATIONAL EXPOSURE LIMITS: TLV (as Se): 0.2 mg/m3 (ACGIH 2000). MAK: (measured as respirable fraction) 0.05 mg/m3; II,1 (1999) ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation of its aerosol and by ingestion. INHALATION RISK: Evaporation at 20°C is negligible; a harmful concentration of airborne particles can, however, be reached quickly when dispersed . EFFECTS OF SHORT-TERM EXPOSURE: The substance is corrosive to the eyes, the skin and the respiratory tract. Inhalation of may cause lung oedema (see Notes). The substance may cause effects on the eyes , resulting in allergic-type reaction of the eyelids (rose-eye). Medical observation is indicated. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: Repeated or prolonged contact may cause skin sensitization. The substance may have effects on the respiratory tract and gastrointestinal tract , central nervous system and liver , resulting in nasal irritation, persistent garlic odour, stomach pain, nervousness and liver impairment . PHYSICAL PROPERTIES Melting point (decomposes): 70°C Density: 3.0 g/cm3 Solubility in water, g/100 ml at 20°C: 167 Vapour pressure, Pa at 15°C: 266 ENVIRONMENTAL DATA The substance is harmful to aquatic organisms. N O T E S The symptoms of lung oedema often do not become manifest until a few hours have passed and they are aggravated by physical effort. Rest and medical observation is therefore essential. Immediate administration of an appropriate spray, by a doctor or a person authorized by him/her, should be considered. Transport Emergency Card: TEC (R)-61G664 ADDITIONAL INFORMATION ICSC: 0945 SELENIOUS ACID (C) IPCS, CEC, 1994

IMPORTANT LEGAL NOTICE: Neither NIOSH, the CEC or the IPCS nor any person acting on behalf of NIOSH, the CEC or the IPCS is responsible for the use which might be made of this information. This card contains the collective views of the IPCS Peer Review Committee and may not reflect in all cases all the detailed requirements included in national legislation on the subject. The user should verify compliance of the cards with the relevant legislation in the country of use. The only modifications made to produce the U.S. version is inclusion of the OSHA PELs, NIOSH RELs and NIOSH IDLH values.