Parents were warned to limit their children's consumption of soft drinks amid fears over the safety of a commonly-used preservative. Research shows that E211 - found in drinks such as Fanta and Pepsi Max - can switch off vital parts of DNA, causing serious damage to cells. . . . Sodium benzoate has been used as a preservative for decades by the £74billion global carbonated drinks industry. It is used to kill yeast, bacteria, and fungi in soft drinks, jam, fruit juice and salad dressing. When mixed with vitamin C it forms benzene, a carcinogenic substance.