CFSAN/Office of Food Additive Safety
May 19, 2006; Updated March 27, 2007 and July 12, 2007
Benzene is a chemical that is released into the air from emissions from automobiles and burning coal and oil. It is also used in the manufacture of a wide range of industrial products, including chemicals, dyes, detergents, and some plastics.
Benzene is a carcinogen that can cause cancer in humans. It has caused cancer in workers exposed to high levels from workplace air. Based on results from a Center for Food Safety and Applied Nutrition (CFSAN) survey of almost 200 samples of soft drinks and other beverages tested for benzene conducted from 2005 through May 2007, a small number of products sampled contained more than 5 parts per billion (ppb) of benzene. The manufacturers have reformulated products, if still manufactured, which were identified in the survey as containing greater than 5 ppb benzene. CFSAN tested samples of these reformulated products and found that benzene levels were less than 1.5 ppb. The US Environmental Protection Agency (EPA) has established a maximum allowable level (MCL) for benzene in drinking water of 5 ppb. FDA has adopted EPA’s MCL for drinking water as an allowable level for bottled water.
The results of CFSAN's survey indicate that the levels of benzene found in beverages to date do not pose a safety concern for consumers. Almost all samples analyzed in our survey contained either no benzene or levels below 5 ppb. Furthermore, benzene levels in hundreds of samples tested by national and international government agencies and the beverage industry are consistent with those found in our survey.
Benzene can form at very low levels (ppb level) in some beverages that contain both benzoate salts and ascorbic acid (vitamin C) or erythorbic acid (a closely related substance (isomer) also known as d-ascorbic acid). Exposure to heat and light can stimulate the formation of benzene in some beverages that contain benzoate salts and ascorbic acid (vitamin C). Sodium or potassium benzoate may be added to beverages to inhibit the growth of bacteria, yeasts, and molds. Benzoate salts also are naturally present in some fruits and their juices, such as cranberries, for example. Vitamin C may be present naturally in beverages or added to prevent spoilage or to provide additional nutrients.
FDA is working with the beverage industry to minimize benzene formation in products. For example, FDA has met with industry to determine the factors contributing to benzene formation. FDA has directly contacted those firms whose products were tested and found to contain more than 5 ppb benzene in our survey. Manufacturers have reformulated products to ensure benzene levels are minimized or eliminated. The International Council of Beverages Associations and the American Beverage Association have developed guidance for all beverage manufacturers on ways to minimize benzene formation. FDA will continue its testing program for benzene in soft drinks and other beverages to monitor levels and will inform the public and manufacturers as new data become available.
FDA first became aware that benzene was present in some soft drinks in 1990. At that time, the soft drink industry informed the agency that benzene could form at low levels in some beverages that contained both benzoate salts and ascorbic acid. FDA and the beverage industry initiated research at that time to identify factors contributing to benzene formation. This research found that elevated temperature and light can stimulate benzene formation in the presence of benzoate salts and ascorbic acid. As a result of these findings, many manufacturers reformulated their products to reduce or eliminate benzene formation.
In November 2005, FDA received reports that benzene had been detected at low levels in some soft drinks containing benzoate salts and ascorbic acid. CFSAN immediately initiated a survey of benzene levels in soft drinks and other beverages. The vast majority of the beverages sampled to date (including those containing both benzoate salts and ascorbic acid) contained either no detectable benzene or levels well below the 5 ppb EPA MCL for benzene in drinking water.
To date, FDA has tested almost 200 soft drink and other beverages in the CFSAN survey. Benzene above 5 ppb was found in a total of ten products. Benzene above 5 ppb was found in nine of the beverage products that contain both added benzoate salts and ascorbic acid. FDA also found benzene above 5 ppb in one cranberry juice beverage with added ascorbic acid but no added benzoates (cranberries contain natural benzoates). The manufacturers have reformulated products, if still manufactured, which were identified in the survey as containing greater than 5 ppb benzene. CFSAN tested samples of these reformulated products and found that benzene levels were less than 1.5 ppb. See also Data on Benzene in Soft Drinks and Other Beverages, including product names and benzene levels.
FDA's TDS is an ongoing FDA program that determines levels of various contaminants and nutrients in a broad variety of foods. As was previously reported by the press, FDA's TDS results from 1995 to 2001 included benzene levels in some beverages that were elevated compared with results from CFSAN's survey and other recent domestic and international studies. In 2006, the FDA conducted an evaluation1 of the reliability of the TDS benzene results. This evaluation concluded that the TDS procedure used to analyze benzene levels can generate benzene in beverages containing benzoate preservatives. There was also evidence of a source of benzene contamination in the TDS laboratory. Although the FDA evaluation focused on benzene in beverages, these findings also raise questions about the reliability of the method for benzene in solid foods. Because the TDS benzene results appeared to be unreliable, FDA scientists recommend that the benzene data be viewed with great caution while FDA considers removing TDS benzene data from the TDS website. There is no evidence of problems with other TDS data.
1Summary of an Investigation of the Reliability of Benzene Results from the Total Diet Study, FDA, December 8, 2006. Available from Judith Kidwell, CFSAN/Office of Food Additive Safety, E-mail: .
See also Data on Benzene in Soft Drinks and Other Beverages July 12, 2006
Chemical Name: benzene
IUPAC International Chemical Identifier: InChI=1/C6H6/c1-2-4-6-5-3-1/h1-6H