Potassium benzoate
Benzoate preservative; same benzene/vitamin C concern.
- Category
- Preservatives
- Acceptable daily intake
- 5 mg/kg body weight/day (EFSA)
- Vegan
- Yes
- Vegetarian
- Yes
What it is
Potassium benzoate (E212) is a synthetic preservative. It is highly soluble and works best in acidic environments to stop yeast and mould growth.
How it is used in food
Effective against yeasts in acidic drinks, chosen for low-sodium recipes.
Commonly found in- Diet sodas and fruit juices
- Syrups and cordials
- Pickles
Health and safety
Same benzene-formation caution when combined with vitamin C.
Like all benzoates (including E211), the primary hazard is the potential for benzene formation.
Can form benzene in vitamin C drinks
In acidic drinks that also contain ascorbic acid, benzoates can break down under heat or light to form benzene, a Group 1 carcinogen. FDA testing found most beverages at or below the 5 ppb drinking-water limit and the reaction is now designed around, so the exposure risk is low — but it is the reason to prefer sorbates in vitamin C products.
Questions and Answers on the Occurrence of Benzene in Soft Drinks and Other Beverages
Shares the general benzoate family concerns.
Regulatory status
| Region | Status | Notes |
|---|---|---|
| Australia & New Zealand FSANZ |
Permitted | Permitted. |
| European Union EFSA / European Commission |
Permitted | Authorised for food use under EU regulations (Annex II). |
| United States FDA (Food and Drug Administration) |
Permitted | Listed by FDA as an antimicrobial agent, but with no direct food additive listing — 21 CFR 184 affirms benzoic acid and sodium benzoate, and the only regulation citing potassium benzoate is for food-contact gaskets. Its use in US foods rests on independent GRAS determinations. |
Identification on labels
- E-number
- E212
Alternatives to this additive
- E202: Potassium sorbate — Does not form benzene and is widely considered much safer.
How it is made
Produced industrially through the oxidation of toluene (a petrochemical) or by neutralizing benzoic acid.
- Synthesis — Toluene is oxidized to benzoic acid, which is then neutralized if forming a salt.
Worth knowing
The potassium form of sodium benzoate.
Conclusion
The concern with benzoates is a specific reaction, not the preservative itself: combined with vitamin C in an acidic drink and left in heat or light, they can form benzene, a Group 1 carcinogen. FDA's survey found most beverages at or below the 5 ppb drinking-water limit, and formulators now avoid the combination — but it is why sorbates are preferred in vitamin C products.
References
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Open the appEntry last reviewed 2026-07-28.
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