Sulfites (sulfiting agents; SO2 equivalents)

What this is

Sulfites sit in a middle zone: useful and permitted, but not invisible from a safety perspective. U.S., EU, Canadian, and Australian/New Zealand rules all require special disclosure around a 10 ppm or 10 mg/kg threshold, because sensitive consumers can have reactions. The main practical issue is not a broad population ban; it is acute intolerance or hypersensitivity, especially asthma-like reactions in susceptible people. FDA still allows several sulfiting agents as food ingredients under good manufacturing practice, but excludes uses in meats, foods recognized as vitamin B1 sources, and raw or fresh fruits and vegetables. EFSA's 2022 reassessment was more cautious than older ADI-based framing: it withdrew the temporary group ADI because the toxicity database was inadequate and used a margin-of-exposure approach. EFSA found possible concerns for high consumers and called out data gaps, including hypersensitivity and toxic-element specifications. JECFA's database likewise notes that high regular consumers of sulfite-containing foods or wine may exceed the older ADI, depending on national diets.

Safety Review

The critical endpoints experts review in safety assessments. This is not a prediction of harm.

The main consumer-facing toxicology note is acute sensitivity: susceptible people, especially some asthmatics, can react and need labels to avoid sulfites. EFSA's 2022 follow-up used a margin-of-exposure approach after withdrawing the temporary ADI, flagged high-consumer concerns and data gaps, and FDA excludes use in vitamin B1-source foods because sulfites can destroy thiamine.