A3.2.1 Sulphur
Sulphur Dioxide
Sulphur Dioxide is a chemical compound (more than one atom joined together), with the chemical formula SO2 [This means it is one atom of Sulphur joined to 2 atoms of Oxygen]. It is a colourless gas, which is soluble in water. It may also be oxidised within airborne water droplets. If this occurs in the presence of Nitrogen Oxide, it can form Sulphuric Acid (H2SO4), which is a cause of acid rain.
SO2 is produced naturally by volcanoes and is also emitted by man through industrial processes. For example, coal and petroleum often contain sulphur compounds; their combustion generates sulphur dioxide. The burning of coal is said to be the source of half of annual SO2 emissions globally.
According to http://www.airquality.co.uk, even moderate concentrations may result in a fall in lung function in asthmatics. At higher levels tightness in the chest and coughing occur.
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