Sodium Sulfite
The short version
A sulfite preservative and antioxidant that releases SO2 to stop browning — a declared allergen above 10 mg/kg.
A sulfite preservative. It's effective, but sulfites can set off asthma and other reactions in sensitive people, so they must be declared on labels. That's why we flag it.
Safety profile
JECFA's group ADI is 0–0.7 mg/kg body weight as SO2 (shared by the sulfites). In 2022 EFSA withdrew its temporary group ADI because the available toxicity data were inadequate to derive an ADI, and concluded that estimated dietary exposures raise a safety concern. Sulfites can trigger asthma and reactions in sensitive people; declaration is mandatory above 10 mg/kg.
Sources
- EFSA FAF Panel — Follow-up of the re-evaluation of sulfur dioxide (E 220), sodium sulfite (E 221), ... calcium sulfite (E 226), calcium bisulfite (E 227) and potassium bisulfite (E 228) (2022) — European Food Safety Authority (EFSA Journal 2022;20(11):7594), 2022. Safety: EFSA withdrew the temporary group ADI and found a safety concern
- WHO JECFA database — Sodium sulfite (INS 221) — Joint FAO/WHO Expert Committee on Food Additives (WHO), 1998. Safety: JECFA group ADI 0-0.7 mg/kg bw as SO2
- 21 CFR 182.3798 — Sodium sulfite (eCFR, current as of 13 Oct 2026) — US eCFR / Office of the Federal Register, 2026. Regulation: GRAS in the US with use restrictions
- Regulation (EU) No 1169/2011 on the provision of food information to consumers (OJ L 304, 22.11.2011), Annex II — Publications Office of the EU — Publications Office of the European Union, 2011. Safety/regulation: mandatory sulphite declaration above 10 mg/kg
Checked against these sources on .
Educational information only. Not medical, dietary or veterinary advice. Spotted an error? Tell us.