Sodium Benzoate is a preservative used most prevalently in acidic foods such as salad dressings (vinegar), carbonated drinks (carbonic acid), jams and fruit juices (citric acid), pickles (vinegar), and Chinese food sauces (soy, mustard, and duck).

 

There have been some health concerns about the combination of sodium benzoate and ascorbic acid or vitamin C. When the two are mixed, they can form the chemical benzene, which is carcinogenic so be wary of drinks that contain both ingredients. However, sodium benzoate on its own is not considered a carcinogen.