Sulfur dioxide appears as a colorless gas with a choking or suffocating odor. Boiling point -10°C. Heavier than air. Very toxic by inhalation and may irritate the eyes and mucous membranes. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. Used to manufacture chemicals, in paper pulping, in metal and food processing. Rate of onset: Immediate & Delayed Persistence: Minutes to hours Odor threshold: 1 ppm Source/use/other hazard: Disinfectant and preserving in breweries and food/canning; textile industry; batteries.

1. Used as an organic solvent and refrigerant, and for the refining of various lubricating oils.

2. Mainly used in the production of sulfur trioxide, sulfuric acid, sulfites and thiosulfates; also used as a fumigant, preservative, disinfectant, reducing agent, etc.

3. Sulfur dioxide is a reducing bleaching agent permitted in China. It bleaches food and strongly inhibits oxidases in plant-based foods. China stipulates that it can be used in wine and fruit wine, with a maximum usage level of 0.25 g/kg and a residue limit not exceeding 0.05 g/kg.

4. Used in the industrial sectors of pesticides, man-made fibers, dyes, etc.

5. Used in the production of sulfur, as well as an insecticide and fungicide.

6. According to Claude Ribbe in his book Napoleon's Crimes, sulfur dioxide was used as a poison by some rulers in Haiti in the early 19th century to suppress slave uprisings.