Ingredient · Preservative
Sodium Benzoate
A preservative that suppresses mould and yeast in acidic products such as soft drinks, dressings, and pickles. Effective and inexpensive, and only works in an acidic environment, which is why it shows up alongside citric or phosphoric acid.
also known as E211, Benzoate of soda
Sodium benzoate is well studied on its own. The complication is a specific combination: together with ascorbic acid (vitamin C) it can form small amounts of benzene, a known carcinogen. This was documented in soft drinks in the 2000s and led manufacturers to reformulate.
That is why it is flagged here rather than treated as routine. Seeing sodium benzoate and vitamin C in the same list is the case worth noticing.
Why it’s classified this way
Classified Risky because it can form benzene in the presence of ascorbic acid, so the company it keeps on a label matters.
References
- EFSA re-evaluation of benzoic acid and its salts
- FDA guidance on benzene in soft drinks