Sodium benzoate (E211)
Want to stop a fruit juice, sauce, or fermented food from going bad? Add sodium benzoate—a salt that prevents spoilage. But, like with propylparaben (also on this list), sodium benzoate can produce benzene, a known carcinogen, when exposed to vitamin C. The FDA recognizes this risk, but believes the concentrations are too small to pose a health concern—thankfully, “sodium benzoate” or “E211” must be listed in ingredient labels.