/ ˈsəlfər daˈjɑːkˌsaɪd /
A toxic gas (SO2) that occurs in the gases from volcanoes; used in many manufacturing processes.
SO2 a pungent gas, produced by burning sulfur in air or oxygen.
It is used widely for disinfecting food vessels and equipment, and as a preservative in some food products. It occurs in industrial flue gases and is a major cause of acid rain.