Sulphur dioxide (SO2) is a chemical compound that is commonly found in the environment, particularly in areas where fossil fuels are burned. It is a colourless gas with a pungent, choking odor and is known to be harmful to both human health and the environment. SO2 is primarily produced through the combustion of fossil fuels, such as coal and oil, in industrial processes and transportation. It is also emitted naturally by volcanic activity and forest fires. Once released into the atmosphere, SO2 can react with other chemicals to form harmful particulate matter, including acid rain. Long-term exposure to SO2 can cause respiratory problems, such as asthma and chronic bronchitis, and can also contribute to the formation of smog. To mitigate its negative impacts, various measures are taken to reduce SO2 emissions, including the use of cleaner fuels, improved industrial processes, and the implementation of air pollution control technologies.