Sodium Benzoate: Preservative or Carcinogen?
Sodium benzoate is a preservative, a bacteriostatic and fungistatic which is used in acidic products, as it requires a pH level of less than 3.6 in order to be effective. It is the most common preservative found in soft drinks, and while considered safe at levels of 0.1% by weight, excessive consumption of things such as processed foods and soft drinks or secondary exposures may not have been fully considered.
Preservatives are good, you might say. They keep processed foods safe for consumption by retarding bacterial growth, which must be a good thing, right? Of course, but consider this: this particular preservative is also used in fireworks and rocket fuel. Appetizing, no?
Unfortunately, increasing the safety of processed foods and drinks is only one part of the story. Studies have linked sodium benzoate to damage to mitochondria in cells and a cause of cell death; there are many diseases now believed to be due to this damage, including many neurodegenerative diseases, such as Alzheimers and Parkinson's disease.
It has also been linked, although not proven definitively, to hyperactivity in children, but is currently believed that it is only when in combination with some artificial colorings that it has this effect.
“However, parents should not think that simply taking these additives out of food will prevent all hyperactive disorders. We know that many other influences are at work but this, at least, is one a child can avoid,” says Professor Jim Stevenson of Southampton University, who led the study and authored the 2007 report.
Benzene, which is formed when sodium benzoate is combined with ascorbic acid, or vitamin C, is an established carcinogen, of which low level exposure can cause sleepiness, light-headedness, increased heart rate, and tremors. As exposure increases, the effects can be vomiting, convulsions and, in extreme cases, death. Certainly “acceptable” levels of this, stated by the FDA to be 5ppm or less, would not cause the more extreme effects in the average person, but when one considers the prevalence of soft drinks in our culture, and the increased exposure, the picture may become more grim.
The formation of benzene in such drinks is, of course, rare. It requires a certain combination of ingredients, specific storage conditions, and time, however, in 2006, the British Food Standards Agency conducted a study of 150 brands of soft drinks, finding that four contained benzene levels which were above acceptable levels.
The true problem, of course, lies not in using such chemicals as preservatives in food manufacturing; chemical preservatives are nearly unavoidable and, indeed, are highly desireable, as opposed to the effects of say, botulism poisoning, but it's another case of “everything in moderation”. Soft drinks are not meant to be consumed at the levels that they currently are in our culture. In Canada, in 2002, the average consumption was 119.8 litres per person per annum; in the US, that figure was nearly doubled. If that is the average, consider that many people don't drink soft drinks at all, and that changes the picture remarkably.
Again, it comes down to being aware of what you're putting into your body, and making wise decisions. Learn how to read nutritional labels, which have been required on all prepackaged food in Canada since December of 2007. Get into the habit of reading the ingredient list on processed food products which you consume regularly, and question which chemicals are present in your food and why. Making wise decisions may not totally safeguard your long-term health, but it will certainly lessen your risk factors, and in this world we live in, where cancer, neurological disorders, and heart disease are so common, any advantage is a good thing.