A new scare over soft drinks is in the making following revelations that a common preservative found in such popular brands like Fanta and Pepsi Max has the ability to switch off vital parts of DNA. That would mean serious cell damage.
For when parts of DNA are disabled, as it were, it could eventually lead to cirrhosis of the liver and degenerative diseases such as Parkinson's.
Concerns centre on the safety of E211, known as sodium benzoate, a preservative used for decades by the Ģ74bn global carbonated drinks industry. Sodium benzoate derives from benzoic acid. It occurs naturally in berries, but is used in large quantities to prevent mould in soft drinks such as Sprite, Oasis and Dr Pepper. It is also added to pickles and sauces.
Sodium benzoate has already been the subject of concern about cancer because when mixed with the additive vitamin C in soft drinks, it causes benzene, a carcinogenic substance. A Food Standards Agency survey of benzene in drinks last year found high levels in four brands which were removed from sale.
Now, an expert in ageing at Sheffield University, who has been working on sodium benzoate since publishing a research paper in 1999, has decided to speak out about another danger. Professor Peter Piper, a professor of molecular biology and biotechnology, tested the impact of sodium benzoate on living yeast cells in his laboratory. What he found alarmed him: the benzoate was damaging an important area of DNA in the "power station" of cells known as the mitochondria.
He said, "These chemicals have the ability to cause severe damage to DNA in the mitochondria to the point that they totally inactivate it: they knock it out altogether. "The mitochondria consumes the oxygen to give you energy and if you damage it - as happens in a number if diseased states - then the cell starts to malfunction very seriously. And there is a whole array of diseases that are now being tied to damage to this DNA - Parkinson's and quite a lot of neuro-degenerative diseases, but above all the whole process of ageing."
But drinks manufacturers argue that sodium benzoate has been approved for use by regulators. A spokesman for Britvic, which makes Pepsi Max in the UK, said: "Obviously, like other soft-drinks manufacturers, we will only use additives that are thoroughly tested and approved for use in this country by both the FSA and the EU."
Coke contains no sodium benzoate, but it is found in many of Coca-Cola's other brands such as Oasis, Dr Pepper and Sprite. A spokesman for Coca-Cola said: "We use preservatives in some of our products - particularly those that include fruit - to ensure that they remain unspoiled throughout their shelf life, whether people are able to store them in a fridge or not.
"All our ingredients have been approved as safe by the food regulatory authorities in Britain and the EU and that is where we take our guidance from." The British Soft Drinks Association described the safety of additives as "an area" for the Food Standards Agency. The FSA said additives had been approved by the European Commission. "Sodium benzoate and benzoic acid are approved for food use," the FSA said in a statement. "Food additives are only permitted for use after a long and careful process of evaluation. This includes rigorous assessments for safety, undertaken by independent scientific committees."
Nonetheless, manufacturers and retailers have begun to remove additives from food and drinks. Sainsbury's will have removed almost all artificial colourings, flavourings and benzoate preservatives by the end of June. Marks & Spencer will phase out additives by the end of this year. And Asda will do the same for its own-brand products by the end of 2007.
Despite maintaining that there is no safety risk, the soft-drinks manufacturers are also responding to public and especially parental concern. Britvic, which issued the statement above, has taken sodium benzoate out of several drinks aimed at children, such as Fruit Shoots and some of its Robinson's range. Its website says it recognises parental concern about sodium benzoate, will not use it in new products and intends to remove it from other products "where possible".
A review of sodium benzoate by the World Health Organisation in 2000 concluded that it was safe, but it noted that the available science supporting its safety was "limited". Professor Piper, whose work has been funded by a government research council, said tests conducted by the US Food and Drug Administration were out of date. "The food industry will say these compounds have been tested and they are complete safe," he said. "By the criteria of modern safety testing, the safety tests were inadequate. Like all things, safety testing moves forward and you can conduct a much more rigorous safety test than you could 50 years ago."