Benzene Redux: This Time It's Soda

Related articles

Talk about recycling! Not only do we recycle our bottles, paper, and aluminum foil, we're also poised to recycle our health scares. Like the mythical snake that swallows its own tail, fear of benzene has come around again, since it has been found in very tiny amounts (we're talking parts per billion) in some soft drinks.

Imperiled Perrier Parallels

This is not to say that benzene is an innocuous chemical. It's known to cause leukemia and aplastic anemia in people who are occupationally exposed to high levels of benzene for a number of years -- and here we're referring to parts per million (a thousandfold higher than parts per billion). People can be exposed to benzene from industrial sources in the air they breathe, as well as from natural sources including volcanoes and forest fires. Industrial sources of benzene are derived primarily from petroleum.

Benzene is a very useful compound. Various industries use it in the production of numerous other chemicals, such as styrene (used to manufacture a number of plastics) and some lubricants, dyes, detergents, and drugs. Other exposures to benzene come from crude oil, gasoline, and cigarette smoke. In fact, a 1989 report in Environmental Health Perspectives noted that "more than half the entire nationwide exposure to benzene results from smoking tobacco or being exposed to tobacco smoke." (1)

Back in 1990, workers examining bottled Perrier water were surprised to find that it contained low levels of benzene -- on the order of 12 to 20 parts per billion (for some perspective on this dose, one part per billion would be one second of time in 32 years -- it's a very small amount). This finding ignited a firestorm: Perrier recalled its entire U.S. inventory and halted production worldwide while they searched for the source of "contamination." Ironically, there was no external contamination of their water source -- the benzene was naturally present in the spring that was their source. The company replaced the filters in their processing plant, and the spring was recertified. Further, the FDA emphasized the very low risk -- lifetime consumption of 16 ounces of Perrier a day might increase the lifetime risk of cancer by one in one million. (2)

Scared of Soda

Now we're seeing a similar sort of scare, one based on even lower levels of benzene in some soft drinks. Tests conducted on a number of soft drinks in Britain and France revealed levels of benzene as high as 8 parts per billion (ppb). Since the British upper limit for benzene in water is only one ppb, the Food Standards Agency (FSA -- the British equivalent of our FDA) is calling for further investigations, although the agency stated that there was no immediate health threat.

Where does the benzene in soft drinks come from? Like the Perrier situation, there is no external contamination involved. Apparently, preservatives used to prevent bacterial growth, sodium benzoate or potassium benzoate, can react with the vitamin C added to many drinks to form benzene.

This chemical reaction has been understood for many years. In the early 1990s, the FDA was alerted to this possibility and conferred with the soft drink industry about it. The industry, in turn, proceeded to reformulate their products to avoid benzene production. In 1993, the FDA again tested soft drinks and found no problem. Since then, however, many new drinks produced by new companies have been marketed, and it's not clear that all are knowledgeable about the possibility of benzene formation.

In the United States, the EPA's limit for benzene in water is 5 ppb, and thus the levels of 8 ppb are considered excessive. As one might expect, the usual scaremongers are attempting to frighten consumers about the presence of this "carcinogen" in soft drinks. As usual, they target parents -- warning them about this supposed danger to their offspring -- even though they acknowledge that they have no evidence that benzene is actually present in the beverages they list as problematic.

What the scaremongers don't acknowledge is that even levels slightly above the EPA limits are unlikely to present real health threats. First, the amounts under discussion are extraordinarily small. Back in 1990, the FDA counseled that the levels in Perrier should not be a cause for great concern -- and those levels (12-20 ppb) were greater than those found recently in soft drinks. More important, the limits set by regulatory agencies are based on consumption of large amounts of water, every day for many years, and aren't particularly relevant to occasional consumption of small or moderate amounts.

On the list of health risks to be concerned about, benzene in soft drinks has to be way down. Recycling paper and cans may be a reasonable activity, but the benzene health scare should be tossed out with the non-recyclable trash.

(1) Raloff J. Biggest benzene risks hide close to home. Science News. October 14, 1989:245.

(2) Meier, B. Perrier recalls its water in U.S. after benzene is found in bottles. The New York Times. February 10, 1990:1.

Ruth Kava, Ph.D., R.D., is Director of Nutrition at the American Council on Science and Health (ACSH.org, HealthFactsAndFears.com).