Sulfite oxidase deficiency: a high risk factor in SO2, sulfite, and bisulfite toxicity?

It has been hypothesized that sulfite oxidase deficient persons may be at increased risk to toxicity from SO2 and dietary sulfites widely used for food preservation. Sulfite oxidase is believed to be responsible for the detoxification of SO2 and/or sulfite to sulfate for excretion. Human and animal studies have shown that S-sulfonates, believed to transport sulfite in the blood, are formed in response to exposure to low levels of SO2. Besides its numerous toxic effects, e.g. respiratory impairment, interference with immunological response and oxygen transport and platelet aggregation inhibition, SO2 has the ability to alter DNA during replication causing T . A transitions, chromosome abnormalities and depression of DNA synthesis.