March 21, 2006
Mr. Richard Wiles
Senior Vice President
Environmental Working Group
1436 U Street, NW, Suite 100
Washington, DC 20009
Dear Mr. Wiles:
This is in response to your letter of February 28, 2006, to Andrew von Eschenbach, MD, Acting Commissioner of Food and Drugs, asking the Food and Drug Administration (FDA) to issue a warning to the public that soft drinks containing ascorbic acid and benzoate preservatives may contain benzene and to release the results of our tests for the presence of benzene in soft drinks. Your letter was forwarded to the Center for Food Safety and Applied Nutrition (CFSAN) for a response.
In your letter, you contend that FDA has known about the presence of benzene in soft drinks since 1990, suppressed the information from the public, and asked soft drink manufacturers to voluntarily solve the problem. You describe the finding of benzene in soft drinks as a "clear health threat." You have not provided any rationale why the presence of benzene in soft drinks at low parts per billion (ppb) levels should have been considered as a clear health threat at that time or should be considered as such a threat now; both FDA and the Health Protection Branch (HPB) in Canada agreed then, as they agree now that low ppb levels of benzene found in these products did not and do not constitute an imminent health hazard.
Around 1990, FDA was informed by the soft drink industry that benzene, a carcinogen, could form at the ppb level in some beverages that contained benzoate preservatives and ascorbic acid (vitamin C). After learning that benzene was present in some products, research was undertaken by both FDA and industry to understand the factors that contributed to benzene formation. We learned that elevated temperature and light can stimulate benzene formation in the presence of benzoate salts and vitamin C, while sugar and EDTA salts inhibit benzene formation. Contrary to your statement that FDA suppressed information, FDA published its findings in 1993. These findings showed both that benzene was detected only at insignificant levels and that trace levels of benzene could occasionally be detected in foods that did not contain added benzoates and vitamin C.1 Earlier, in 1992, HPB published its findings of a survey in which they sampled fruit, fruit juices, fruit drinks, and soft drinks with and without added benzoate.2 Results of HPB's survey were consistent with our findings.
In November 2005, FDA received private laboratory results reporting low levels of benzene in a small number of soft drinks that contain benzoate preservatives and ascorbic acid. As follow-up to these findings, FDA began collecting and analyzing a small sample of beverages with a focus on those products that contain both benzoate and ascorbic acid.
Based on currently available results from this limited survey. the vast majority of beverages sampled (including those containing both benzoate preservative and ascorbic acid) contain either no detectable benzene or levels below the 5 ppb limit for drinking water, and do not suggest a safety concern.
Your letter includes a list of beverage products that were purchased in retail outlets and that contain ascorbic acid and benzoates. You cite this list as evidence that the beverage industry has not eliminated the chemical combination that can form benzene. You should know, however, that the presence of benzoates and vitamin C in a product cannot be used to conclude that elevated levels of benzene have or will form. In fact, in our current analyses, the vast majority of beverages containing both benzoate preservative and ascorbic acid contained either no detectable benzene or levels below 5 ppb.
FDA is continuing to sample beverages to gain more representative data on the current situation. We intend to release our results when we have a more complete understanding of the current marketplace. Although the results to date are preliminary, they do not suggest a safety concern. Additionally, the agency has been in contact with manufacturers and industry trade associations. They have informed FDA that they are actively assessing whether their products contain benzene and will take appropriate steps to minimize benzene formation in their products, if elevated levels are found.
FDA is also following up with companies whose samples of products were found to contain elevated levels of benzene in our initial survey. Once FDA has completed its beverage survey we will determine what, if any, additional action is necessary to protect the public health and to ensure that the levels of benzene in soft drinks marketed in the future are as low as possible. We appreciate your concern regarding this issue.
Robert E. Brackett, Ph.D.
Center for Food Safety and Applied Nutrition
1McNeal et al., J. AOAC Intl. 76. 1213-1219 (1993).
2Page et al. J. AOAC Intl. 75. 334-340 (1992).