A molecular biologist at the University of Sheffield in England has raised safety concerns over the use of the preservative sodium benzoate (additive number E211), which is permitted for use in soft drinks, jams, fruit juices and salad dressings across the European Union. Professor Peter Piper found benzoic acid, a precursor to sodium benzoate most commonly used to kill yeast, bacteria, and fungi in soft drinks and other liquids, could damage mitochondrial DNA in yeast cells and lead to neurodegenerative diseases such as Parkinson's, as well as liver damage and signs of ageing.
Sodium benzoate has been deemed safe in the US and Europe and other jurisdictions, but Professor Piper said the ingredient requires reassessment. "By the criteria of modern safety testing, the [original] safety tests were inadequate," he said. "Like all things, safety testing moves forward and you can conduct a much more rigorous safety test than you could 50 years ago. We are feeding vast amounts of [these preservatives] to children inadvertently. Is this a completely safe process?"
He called on the UK Food Standards Agency to investigate but the FSA questioned the relevance of Professor Piper's findings in relation to humans. It said it had considered Professor Piper's first paper on the subject, published in 1999, and deemed no action necessary.
"Food additives are only permitted for use after a long and careful process of evaluation," FSA said. "This includes rigorous assessments for safety, undertaken by independent scientific committees."
A British MP took up Piper's cause and said he would be writing to the FSA to investigate the substance. He also urged parents to limit the amount of benzoate-containing soft drinks their children consumed.
The British Soft Drinks Association defended the ingredient's use. "All ingredients used by the soft drinks industry are considered as safe to use by the FSA," a spokesperson said. "The agency has assured us that the apparent concerns regarding sodium benzoate have already been investigated and it sees no reason to change its view that sodium benzoate is safe. Consumers can continue to enjoy soft drinks in the full confidence that they are safe to drink."