Wednesday, April 05, 2006

Benzene in soft drinks, follow-up

Recently we alerted folks to new findings that the common soft drink preservative sodium benzoate may react with vitamin C (ascorbic acid) to produce benzene, a known human carcinogen. The FDA has known of this connection for at least 15 years, but trusted the soft drink industry to "get the word out" so reformulations could be made to prevent benzene from being produced. This kind of reformulation isn't hard to do.

I don't have to tell you the rest.

So now it's 15 years later and the FDA and European regulatory bodies are trying to play catch up. Among other things, they are finally getting around to testing soft drinks for benzene. Note that there are no benzene standards for soft drinks. The standards are for plain tap water. Soft drinks are regulated by the FDA (the folks who didn't bring you Plan B). Tap water is regulated by EPA. The FDA must believe that when you add artificial flavor and color to the water, benzene can't hurt you any more. Or something.

Anyway. FDA says levels of benzene found in soft drinks are safe. Case closed. Not so, says the Environmental Working Group:
A computer investigation by Environmental Working Group (EWG) has uncovered results from a Food and Drug Administration (FDA) testing program that contradict blanket safety assurances about benzene contamination in soft drinks made by a top agency official on March 21, 2006. FDA's data show that 79 percent of diet soda samples tested over a six-year period from 1995 through 2001 were contaminated with benzene at levels above the federal limit for benzene in tap water.

The FDA test results, buried deep within an obscure FDA food testing program called the Total Diet Study, were posted on EWG's Web site,, just days after a top FDA official assured the public that there was no threat from the presence of the toxic chemical in soft drinks. This weekend, Great Britain's public health agency pulled some soft drink products from store shelves because of benzene contamination.


Between 1995 and 2001, FDA tested 24 samples of diet soda for benzene in its Total Diet Study: Nineteen (79 percent) were contaminated with benzene above the federal tap water standard of 5 parts per billion (ppb). The average benzene level was 19 ppb, nearly four times the tap water standard. The maximum detection was 55 ppb, 11 times the tap water limit. Each test result is from a composite of three individual soda purchases in three different cities that are blended together to make one sample. (Environmental Working Group)
There is more on the EWG website, which you should visit. No brand names were used, but we know the big manufacturers are concerned about the public relations fall out. Coca-Cola is testing its drinks worldwide and some results are reported to be over the US drinking water standard (5 ppb). But don't worry:
Coca-Cola said it had tested drinks for benzene in the past, and stated “unequivocally that our products are safe”. It did not deny some of its drinks contained benzene traces.
“Consumers around the world invite us into their lives more than one billion times a day; we take this relationship and responsibility very seriously,” the group said. (FoodNavigator)
Ah, but that's just the problem, isn't it. Billions of times a day. There is no dispute that benzene is a human carcinogen. Almost all experts also believe there is some risk at every level of exposure. True, at very small exposure levels the risk may also be very small (see our explanation of carcinogen testing here, here, here and here). At the levels of the drinking water standard the risk could even be one in a million or less. But that's where billions of times a day comes in. Because a billion is a thousand million. So small risks with huge population exposures start to pile up. It's like the lottery. Any person's "risk" of winning is small. But every week people win. Winners pile up when billions of tickets are sold. And that's just the tickets with Coke. Since this was discovered some 1500 new formulations of soft drinks with sodium benzoate and ascorbic acids have been put on the marktet.

One of the things you didn't expect to buy with your can of soft drink was a ticket in the cancer lottery. Because you never know when it will be your Unlucky Day.