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E228PreservativeModerate concern
Potassium Bisulfite
In plain words
The short version
A potassium sulfite used in winemaking and foods — releases SO2 and is a declared sulfite allergen.
Why we flag it amber
A sulfite preservative. Like other sulfites it can trigger asthma and reactions in sensitive people and must be declared on labels, which is why we flag it.
Safety profile
Sulfite group. JECFA's group ADI is 0–0.7 mg/kg body weight as SO2; in 2022 EFSA withdrew its temporary group ADI because the toxicity data were inadequate to set one, and concluded that estimated dietary exposure raises a safety concern. Triggers asthma and sensitivity reactions in some people; mandatory sulfite labelling above 10 mg/kg.
The detail
Potassium hydrogen sulfite, the potassium salt of sulfurous acid, usually handled in solution.
Preservative and antioxidant releasing sulfur dioxide — used in winemaking and to protect some foods and beverages against browning and spoilage.
White crystals or solution, water-soluble, with a sulfurous odor.
Permitted in the EU, the US, and globally with sulfite limits and labelling.
Sources
- EFSA FAF Panel — Follow-up of the re-evaluation of sulfur dioxide (E 220) to potassium bisulfite (E 228) (2022) — European Food Safety Authority (EFSA Journal), 2022. Safety: EFSA withdrew the temporary group ADI of 0.7 mg/kg and flagged a safety concern
- JECFA database — Potassium hydrogen sulfite (INS 228) — WHO / Joint FAO/WHO Expert Committee on Food Additives, 2026. JECFA group ADI 0–0.7 mg/kg bw as SO2 (re-listed at the 102nd meeting, 2026)
- 21 CFR 182.3616 — Potassium bisulfite — US eCFR (FDA). US: GRAS, with exclusions (meats, vitamin B1 sources, fresh fruit and vegetables)
- Regulation (EU) No 1169/2011 on food information to consumers, Annex II (allergens) — Publications Office of the EU (Official Journal), 2011. Mandatory sulfite labelling above 10 mg/kg
Checked against these sources on .
Educational information only. Not medical, dietary or veterinary advice. Spotted an error? Tell us.