Sodium hydrogen sulfite or sodium bisulfite is a chemical compound with the chemical formula NaHSO₃. Sodium bisulfite is a food additive with E number E222. Sodium bisulfite can be prepared by bubbling sulfur dioxide in a solution of sodium carbonate in water. Sodium bisulfite in contact with chlorine bleach (aqueous solution of sodium hypochlorite) will release harmful fumes

A composition or solution thereof for the removal of hydrogen sulphide contaminant which comprises a sulphite and or a bisulphite and one or more additives selected from the group comprising a metal sequestering agent, a pH modifier, a corrosion inhibitor and a scale inhibitor

Potassium hydrogen sulfite or potassium bisulfite is a chemical compound with the chemical formula KHSO₃. It is used during the production of alcoholic beverages as a sterilising agent.