Sulfites or sulphites are compounds that contain the sulfite ion (or the sulfate(IV) ion, from its correct systematic name), SO2−
3. The sulfite ion is the conjugate base of bisulfite. Although its acid (sulfurous acid) is elusive,[1] its salts are widely used.
Sulfites are substances that naturally occur in some foods and the human body. They are also used as regulated food additives.[2] When in food or drink, sulfites are often lumped together with sulfur dioxide.[3]