Makers of cola soft drinks and other food and beverage products containing caramel coloring could soon face lawsuits under California’s Proposition 65 as well as other types of litigation around the country in response to a recent petition filed by the Center for Science in the Public Interest (CSPI). In February, the CSPI formally petitioned the U.S. Food and Drug Administration (FDA) to ban artificial caramel coloring containing an impurity allegedly formed during processing. According to the CSPI’s petition, the substance, 4-methylimidazole (4-MEI), is not added to the coloring. Instead, it is formed as a byproduct of the reaction between sugars and ammonia or ammonia-sulfite during processing.
On January 11, 2011, California added 4-MEI to its list of substances known to the State to cause cancer or reproductive toxicity. Under California’s Safe Drinking Water and Toxic Enforcement Act of 1986 – popularly known as Proposition 65 – products that contain a listed substance above a minimum threshold must disclose on their label that they contain a chemical of concern. Private parties may file suit under Prop 65 against anyone doing business in the state alleged to be in violation of the labeling requirements, but they must provide notice to the defendant and the state attorney general 60 days prior to filing the complaint.
The proposed “no significant risk level” for 4-MEI of 16 micrograms per day has not gone into effect yet and is the subject of a hearing in California scheduled for March 10, 2011. In a December 2010 article in the Journal of Agricultural and Food Chemistry, researchers from the University of California, Davis, noted that three popular cola drinks they evaluated contained between 0.30 and 0.36 micrograms per milliliter of 4-MEI. According to the CSPI, when this figure is converted into a typical 12-ounce can of soda, the amount of 4-MEI would be between 108 and 130 micrograms, which would exceed the daily safe level proposed in California.
According to California health authorities, there are no human carcinogenicity studies of 4-MEI. The only cancer bioassays available for estimating the potency of 4-MEI were conducted on mice and published by the National Toxicology Program in 2007. The CSPI even acknowledged that 4-MEI is not a particularly potent carcinogen and that the sugar in soft drinks is much more harmful to health. It also noted that the risk from caramel coloring in soy sauce and other products is minimal because Americans consume much less of these products compared to cola. Nevertheless, it has asked the FDA to ban all caramel food colorings that are processed with ammonia or ammonia-sulfite.
Of the four categories of FDA-approved caramel coloring additives, only two are processed with ammonia or ammonia-sulfite. The first, category 3 caramel, is typically used in beer, sauces, gravy, baking products, and other foods. The second, category 4 caramel, is typically used in cola soft drinks, blended whisky, and other foods. The CSPI also asked FDA to ban caramel coloring processed with ammonia because of the presence of 2-methylimidazole, which is not listed on the Proposition 65 list but which the CSPI says is carcinogenic. And the CSPI insisted that FDA prohibit the use of the term “natural” on the label of any product containing caramel coloring.
The caramel coloring “crisis” is reminiscent of the controversy surrounding acrylamide in 2002. Back then, Swedish researches found elevated levels of acrylamide (another Prop 65 list carcinogen) in starchy foods, such as potato chips and French fries, cooked at high temperatures. As in the case with 4-MEI, acrylamide is a byproduct of the production process and is not added intentionally. After the discovery, several prominent fast food restaurant chains and snack food producers were sued under Prop 65 and eventually were forced to change their processes to reduce the concentration of acrylamide and add a warning label to their products or post a warning at their stores in California. Notably, the very same activist group – the CSPI – was instrumental in publicizing the acrylamide findings and creating a media frenzy by targeting McDonald’s, Burger King and Frito Lay. The CSPI is employing the same tactics here by going after Coke and Pepsi. No word from the FDA on when — or whether — it will respond to the CSPI petition.