International Chemical Safety Cards DI-n-BUTYLTIN OXIDE ICSC: 0256 Dibutyltin oxide Dibutyloxostannane Dibutyloxotin C8H18OSn/(C4H9)2SnO Molecular mass: 248.9 ICSC #    0256 CAS #     818-08-6 RTECS # WH7175000 UN #        3146 April 22, 1994 Peer reviewed TYPES OF HAZARD/ EXPOSURE ACUTE HAZARDS/ SYMPTOMS PREVENTION FIRST AID/ FIRE FIGHTING FIRE Combustible. Gives off irritating or toxic fumes (or gases) in a fire. NO open flames. Water spray, powder, carbon dioxide. EXPLOSION Finely dispersed particles form explosive mixtures in air. Prevent deposition of dust; closed system, dust explosion-proof electrical equipment and lighting. Prevent build-up of electrostatic charges (e.g., by grounding). EXPOSURE PREVENT DISPERSION OF DUST! STRICT HYGIENE! AVOID EXPOSURE OF (PREGNANT) WOMEN! IN ALL CASES CONSULT A DOCTOR!  •INHALATION Headache. Ringing in the ears, memory loss, disorientation. Local exhaust or breathing protection. Fresh air, rest. Refer for medical attention.  •SKIN MAY BE ABSORBED! Skin burns. Pain (Further see Inhalation). Protective gloves. Remove contaminated clothes. Rinse and then wash skin with water and soap. Refer for medical attention.  •EYES Redness. Pain. 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 (further see Inhalation). Do not eat, drink, or smoke during work. Wash hands before eating. Rinse mouth. Give a slurry of activated charcoal in water to drink. Induce vomiting (ONLY IN CONSCIOUS PERSONS!). Refer for medical attention. SPILLAGE DISPOSAL STORAGE PACKAGING & LABELLING Do NOT wash away into sewer. Sweep spilled substance into containers; if appropriate, moisten first to prevent dusting. Carefully collect remainder, then remove to safe place (extra personal protection: P3 filter respirator for toxic particles). Separated from food and feedstuffs. Unbreakable packaging; put breakable packaging into closed unbreakable container. Do not transport with food and feedstuffs. R: S: UN Hazard Class: 6.1 SEE IMPORTANT INFORMATION ON BACK ICSC: 0256 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 DI-n-BUTYLTIN OXIDE ICSC: 0256 I M P O R T A N T D A T A PHYSICAL STATE; APPEARANCE: WHITE POWDER. PHYSICAL DANGERS: Dust explosion possible if in powder or granular form, mixed with air. If dry, it can be charged electrostatically by swirling, pneumatic transport, pouring, etc. CHEMICAL DANGERS: The substance decomposes on heating producing toxic fumes of tin, tin oxides. OCCUPATIONAL EXPOSURE LIMITS: TLV (as Sn): ppm; 0.1 mg/m3 (skin) (ACGIH 1992-1993). ROUTES OF EXPOSURE: The substance can be absorbed into the body by inhalation, through the skin 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 irritates the eyes, the skin and the respiratory tract. The substance may cause effects on the central nervous system , resulting in impaired functions. Exposure may result in death. The effects may be delayed. Medical observation is indicated. EFFECTS OF LONG-TERM OR REPEATED EXPOSURE: The substance may have effects on the liver , resulting in liver impairment. Animal tests show that this substance possibly causes malformations in human babies. PHYSICAL PROPERTIES Decomposes below melting point at 210°C (see Notes) Relative density (water = 1): 1.6 Solubility in water: none Auto-ignition temperature: 279°C ENVIRONMENTAL DATA This substance may be hazardous to the environment; special attention should be given to algae and crustacea. N O T E S Different values are found in literature. Depending on the degree of exposure, periodic medical examination is indicated. The symptoms of poisoning do not become manifest until days. Transport Emergency Card: TEC (R)-61G12b ADDITIONAL INFORMATION ICSC: 0256 DI-n-BUTYLTIN OXIDE (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.