Sodium benzoate is a food additive used as a preservative in a variety of processed food products and drinks. When reacted with Vitamin C this substance forms benzene, a known carcinogen. Studies have also linked sodium benzoate with increasing hyperactivity in children and altering DNA structure.

Sodium benzoate derives from benzoic acid. It occurs naturally in berries, but is used in large quantities to prevent mould in many popular soft drinks. It is also added to pickles and sauces.

It has been found that sodium benzoate when mixed with the additive Vitamin C (ascorbic acid) in soft drinks forms benzene, a proven carcinogenic substance, as determined by The Department of health and Human Services (DHHS). Recent research has also linked sodium benzoate to cell damage. The study found that benzoate caused damage to an important area of DNA in the "power station" of cells known as the mitochondria.

"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." explained the study author.

Research paper details:

Piper PW Yeast superoxide dismutase mutants reveal a pro-oxidant action of weak organic acid food preservatives Free Radic Biol Med 1999 Dec;27(11-12):1219-27

A 2007 Lancet study that linked commonly used artificial food colorings with increased hyperactivity in children included the preservative sodium benzoate.

The study, performed at the University of Southampton in the U.K., consisted of 153 three-year-olds and 144 children between the ages of eight and nine. Each child was assigned to one of two groups drinking either juice spiked with a cocktail of artificial additives at levels ordinarily found in sweets, beverages, and other common foods or an unadulterated fruit juice acting as a placebo.

The additives used included sunset yellow (E110), ponceau 4R (E124), carmoisine (E122), tartazine (E102), quinoline yellow (E104), allura red (E129), and the common preservative sodium benzoate (E211).

After six weeks, the group on artificial additives showed significant measurable and cogent increase in hyperactivity. These findings "lend strong support for the case that food additives exacerbate hyperactive behaviors (inattention, impulsivity, and overactivity) in children at least up to middle childhood," wrote the authors.

"We now have clear evidence that mixtures of certain food colours and benzoate preservative can adversely influence the behaviour of children." said Dr. Jim Stevenson, lead author of the study.

Research paper details:

McCann D et al. Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial The Lancet, Volume 370, Issue 9598, Pages 1560 - 1567, 3 November 2007

Sodium benzoate is listed among the ingredients on a product label, sometimes as E211. Although some manufacturers and retailers have begun to remove sodium benzoate from food and drinks, it is still worth checking the labels.

Coverage in the Media

This issue has also been covered in news articles and we shall provide a few samples here:

Soft Drinks Found to Contain High Levels of Cancer-Causing Benzene
Soft Drinks Found to Have High Levels of cancer Chemical
by Rajeev SyalMarch 2, 2006 by the Times. UK

Traces of a carcinogenic chemical have been found in soft drinks at eight times the level permitted in drinking water, it was revealed last night.

Tests conducted on 230 drinks on sale in Britain and France have identified high levels of benzene, a compound known to cause cancer, according to the Food Standards Agency. There is a legal limit of one part per billion of benzene in British drinking water. The latest tests revealed levels of up to eight parts per billion in some soft drinks.

Benzene has been linked to leukaemia and other cancers of the blood. Traces found in Perrier water 15 years ago led to the withdrawal of more than 160 million bottles worldwide. The disclosure has prompted food safety campaigners to demand that the Government reveal which products contain benzene. At present, the drinks identities have not been revealed.

Richard Watts, of Sustain, a pressure group lobbying for better food standards, said that this should be done urgently because the drinks were being marketed to children. The scientific evidence is unclear about whether there is any safe level of benzene. We see no reason why it should be different from the designated safe level in drinking water. If it is unsafe in drinking water, why should it be safe in soft drinks? he said.

The Food Standards Agency, the government watchdog, said that the products did not pose an immediate health risk, but called for further investigation from the British drinks industry. "Let's have further investigations and regular discussions with the drinks industry to check what is happening. If levels are high then the FSA will take action to protect consumers", an agency spokesman said.

Food scientists believe that high levels of benzene may have been produced by the reaction of two commonly used ingredients, sodium benzoate, a preservative, and ascorbic acid (Vitamin C). Sodium benzoate is widely used in the drinks sector. In Britain, it is used in Britvic brands including Britvic 55 apple and orange flavours, Pennine Spring flavoured waters and Shandy Bass.It is not known if any of these products were included in the latest tests. A spokesman for Britvic has previously expressed confidence in its products.

A spokesman for the British soft drinks Association said yesterday that the industry was working to reduce the levels of benzene in soft drinks. "There is an obligation on the industry to have as low a level of benzene as possible and we are looking at ways of reducing the levels - and maybe even removing the preservative - if we can replace it with something else", he said.

When minuscule traces of benzene were discovered in Perrier water 15 years ago, it forced the French company to withdraw millions of bottles.

Tests have been carried out in Europe after US food watchdogs found benzene in juices and sodas. The Food and Drug Administration registered its concern about the possible long-term effects on health.

Professor Glenn Lawrence, of Long Island University, who first conducted tests for benzene in soft drinks 13 years ago, said that the combination of sodium benzoate and Vitamin C was commonly used in drinks in the early 1990s.

He said that drinks firms were now putting Vitamin C back into drinks to encourage consumers to buy the product. He said that this was being done to encourage parents to buy the drinks to improve their children's health but it might just be doing the opposite.

BENZENE FACTS

• Michael Faraday discovered benzene in 1825 when he isolated it from oil gas to form a chemical, six parts carbon, six parts hydrogen

• It is produced during incomplete combustion of carbon-rich substances: it is produced from petrochemicals, but occurs naturally in volcanoes, forest fires and in cigarette smoke

• In the 19th and early 20th centuries it was used in aftershave, for its pleasant smell, and to decaffinate coffee. It is now used as an anti-knock agent in petrol

• It is an aggressive carcinogen and may lead to leukaemia and other cancers of the blood

• In 1993, Professor Glenn Lawrence, of Long Island University, published research showing that the sodium benzoate and Vitamin C found in soft drinks could react to form benzene. He suggested that drink companies were putting Vitamin C into drinks to encourage customers to buy them.

Copyright 2006 Times Newspapers Ltd.

And another:

China joins soft drinks benzene probe

07/03/2006 - China has launched an inquiry into benzene in soft drinks after authorities in the UK and US found drinks containing benzene above the countries' legal limits for drinking water.

Chinese food safety authorities have been studying the potential for benzene residues to form in soft drinks containing ascorbic acid and sodium benzoate, according to local media reports.

A public statement is expected soon. Benzene is listed as a carcinogen by public health authorities.

Food safety bodies from several countries around the world have, in recent weeks, attempted to learn more about the potential for benzene formation in drinks.

Their interest was sparked after the US Food and Drug Administration revealed to BeverageDaily.com it had found some drinks in the US that contained benzene above the five parts per billion legal limit for water there.

Britain's Food Standards Agency (FSA) said it would conduct its own investigation after industry testing on 230 soft drinks found average benzene levels above the UK's one part per billion limit for drinking water.

The tests, done on products at the end of their shelf-life, found benzene levels up to eight parts per billion in some drinks. Benzene is listed as a known carcinogen.

The FSA re-iterated that levels found to date were not a public health concern.

The UK has no limit for benzene in soft drinks, and a spokesperson for the country's soft drinks association said the water limit was not applicable.

Yet, a UK food legislation expert told BeverageDaily.com any court would likely look to the drinking water limit for guidance if considering benzene in soft drinks. Water is still the main ingredient in most soft drinks.

A BeverageDaily investigation over the last couple of months has confirmed from several industry and government sources that benzene can form in drinks when two common ingredients - sodium benzoate and ascorbic acid (Vitamin C) - react.

Both the FDA and the US soft drinks industry has known this for 15 years, as testified by an internal FDA memo date January 1991. The issue was, however, never announced to the public.

The industry told the FDA it would get the word out and reformulate, according to FDA chemist Greg Diachenko. Yet, now the issue has returned. Diachenko said authorities were still evaluating results, but we certainly want to make sure there is some reformulation.

The safety body has come under pressure from campaign groups in recent days to release results from its recent testing on soft drinks.

It was originally alerted to the continuing presence of benzene in drinks by independent laboratory tests in New York.

Results of those tests, passed on to BeverageDaily.com, show a couple of soft drinks in the US up to two-and-a-half and four times above the 10 parts per billion legal limit for drinking water set by the World health Organisation.

Perrier bottled water was recalled for containing lower levels of benzene in 1990.

Kevin Keane, of the American Beverage Association (ABA), assured consumers there was no health risk, but said some brands may not be aware of the potential for sodium benzoate and ascorbic acid to form benzene.

15 years ago it was under control, but this is a fast-growing industry. There are a lot of new companies, a lot of new brands and things have changed,

ABA scientist Mike Redman said companies had learnt to control benzene formation by adjusting levels of the two ingredients in their drinks.

But, Glen Lawrence, a scientist who helped the FDA with testing in 1990, said in an interview with BeverageDaily.com soft drinks firms should not use sodium benzoate and ascorbic acid together.

He was concerned that producers might be adding more Vitamin C into drinks as to target consumer health trends.

There is no good reason to add ascorbic acid (Vitamin C) to soft drinks, and those that may have ascorbic acid naturally in them (juices) should not use sodium benzoate as a preservative. So it is really very easy to avoid the problem.

Lawrence co-authored a 1993 article in the Journal of Agricultural and Food Chemistry, detailing how benzene could form in the acidic conditions of drinks when sodium benzoate and ascorbic acid were present.

And also:

FDA finds benzene in soft drinks
BY David Goldstein

WASHINGTON - When small amounts of benzene, a known cancer-causing chemical, were found in some soft drinks 16 years ago, the Food and Drug Administration never told the public.

That's because the beverage industry told the government it would handle the problem and the FDA thought the problem was solved.

A decade and a half later, benzene has turned up again. The FDA has found levels in some soft drinks higher than what it found in 1990, and two to four times higher than what's considered safe for drinking water.

Both the FDA and the beverage industry said the amounts were small and that the problem didn't appear to be widespread.

"People shouldn't overreact," said Kevin Keane, a spokesman for the American Beverage Association. "It's a very small number of products and not major brands."

"The issue here is not something that should cause anyone alarm or terrific concern," said George Pauli, a top food safety expert at the FDA, "but if there's something that can be reduced, we want to reduce it."

Neither Keane nor Pauli would identify the drinks being tested because the investigation is still under way.

Pauli said that people ingest more benzene by breathing than they would if they drank a can of soda containing the chemical. Small amounts of the chemical also are naturally present in some foods such as fruits, vegetables and dairy products.

Still, Pauli added, "You want to avoid it in any degree you can."

Of the 60 or so varieties of sodas, sports drinks, juice drinks and bottled waters that the FDA has tested so far, benzene levels have ranged from two and three parts per billion to more than 10-20 parts per billion.

The Environmental Protection Agency's safety standard for benzene in drinking water is five parts per billion. If it exceeds that, authorities are required to notify the public.

Keane said it was "tough to compare" the safety standard for water with soft drinks because the water rule is based on the fact that people drink more water each day.

Benzene is an industrial chemical that's found in tobacco smoke, car exhaust and vapors from household products such as paint, detergents and furniture wax. Long-term exposure can cause leukemia and other cancers of the blood, according to the Centers for disease Control and Prevention.

Benzene can show up in soft drinks when two common ingredients react: ascorbic acid, otherwise known as Vitamin C, and either sodium benzoate or potassium benzoate. Both are preservatives used to prevent the growth of bacteria.

But the presence of these chemicals doesn't necessarily produce benzene.

"It's not as simple as looking at the label, and if you see those two, there will be problems," Keane said.

Pauli said that a catalyst such as temperature or light is needed to trigger the formation of benzene. That's what scientists suspect occurred in 1990 when authorities found benzene in products made by Cadbury Schweppes and Koala Springs, an Australian beverage company.

But a health safety watchdog organization said the FDA should inform the public, particularly since so many soft drinks are marketed to children.

"Most people would prefer there are no known human carcinogens in what they drink," said Jane Houlihan, vice president for research at the Environmental Working Group, a nonprofit, nonpartisan scientific research group that studies toxic chemicals. "This is a case where industry agreed to get it out of the products, and all the evidence says they didn't."

Soft drink manufacturers PepsiCo and Coca-Cola declined to comment and referred calls to the American Beverage Association.

When benzene first turned up 16 years ago, FDA officials met with representatives of the beverage industry who "expressed their concern about the presence of benzene traces in their products and the potential for adverse publicity associated with this problem," according to an internal FDA memo from December 1990.

Keane said the industry told the FDA that it was reformulating its products to alleviate the problem. Adding sugar, for instance, or replacing the Vitamin C, can inhibit the chemical reaction that produces benzene, Pauli said.

An FDA official who asked not to be identified said that the agency didn't inform the public about the benzene problem 16 years ago because it didn't consider it a public health concern since the levels were low and the companies were reformulating.

He said the FDA conducted follow-up testing in the early 1990s, but not since because "we thought the problem was gone and over. Then it resurfaced."

The current investigation began when an activist concerned about soft drink machines in schools tried to get the FDA interested in the issue. He then sent lab results showing some soft drinks with higher-than-normal benzene levels.

"Our first reaction was, `Yes, we looked at this in 1990 and essentially there was nothing there,'" Pauli said. "Then he came up with some numbers and we said, `That's not what we came up with back then. We have to go back and look.'"

Asked why the problem would resurface 16 years later, Keane said the industry took the necessary steps at the time, but it's possible some manufacturers just didn't know.

"It's a very fast-growing industry, both in terms of companies and new brands, so a lot has changed in the last 16 years," he said.

Food safety authorities in Great Britain and Australia also are testing soft drinks for benzene.