Sodium chlorite (NaClO2) + activator for chlorine dioxide production belongs to the group known as oxidizing biocides, that are capable, of preventing nutrient transport through the cell walls. Chlorine dioxide can be derived from sodium chlorite by adding a soft acid, such as citric acid, hydrochloric acid or lactic acid. Without the addition of an acid, sodium and chloride remain stable together. Only when an acid is added is the sodium released from the chloride, since acids have a greater affinity for these chloride groups. Important: Sodium chlorite should not be confused with sodium chloride. The latter is common table salt. Neither does sodium chlorite have anything to do with chlorine bleach.
Chlorine dioxide, i.e. the metabolite (CLO2) derived from the reaction of sodium chlorite and an acid, is also called acidified sodium chlorite (ASC) in the food industry. There it is used to disinfect food. This is, because ASC, which is nothing more than sodium chlorite with acid, is considered to be one of the most effective, cheapest and safest means of killing, bacteria, viruses, parasites and microbes.
How does it work? Chlorine dioxide, the product of the reaction of sodium chlorite and acid, is a very reactive electron hunter that immediately removes electrons from pathogenic viruses or other germs. Thus what we have here is an oxidation process. The germs do not survive this. Moreover, even the chlorine dioxide molecule (ClO2) does not survive this reaction and degrades into oxygen, which either combines with hydrogen to form water or with carbon to form carbon dioxide. The remaining chlorine ion then combines with available sodium to form NaCl (table salt). The short-term oxidative stress for the microbes kills them, while the degradation products of the reaction are quite harmless.
How come, chlorine dioxide, which is highly reactive, only kills pathogenic germs? Due to its pH value! This lies below 7, namely in the acidic range. So these pathogens do not survive on oxygen, but on fermentation. Germs gravitate towards an over-acidified milieu, so they settle, where the prevailing pH value is already below 7. There is now plenty of literature and there are internet forums discussing the exact application of sodium chlorite with acid. The quality of all the sodium chlorite preparations on offer should be taken into account. Only top quality is an indication of purity in the manufacturing process.