The chemical is 4-methylimidazole (4-MeI), which is found in some types of caramel color, the artificial coloring used to turn soft drinks and certain foods brown. (Caramel coloring has nothing to do with real caramel, a confection that is created by heating sugar.)
Citing inconclusive animal tests, the U.S. Food and Drug Administration says there is “no reason to believe that there is any immediate or short-term danger presented by 4-MeI at the levels expected in food from the use of caramel coloring.”
The International Agency for Research on Cancer, however, has listed 4-MeI as “possibly carcinogenic to humans.” And in 2012, California began requiring manufacturers to put a warning label on any food product that exposes consumers to more than 29 micrograms of 4-MeI daily. At that level, according to the California Office of Environmental Health Hazard Assessment, the risk of developing cancer is 1 in 100,000 — in other words, for each 100,000 people who consumed 29 micrograms of 4-Mel daily over a lifetime, one person would develop cancer.
Consumer Reports believes that cut-off point is too high.
“It’s possible to get more than 29 micrograms of 4-MeI in one can of some of the drinks we tested,” said Urvashi Rangan, a toxicologist and executive director of Consumer Reports’ Food Safety & Sustainability Center, in the article that reported the study’s findings. “Given that coloring is deliberately added to foods, the amount of 4-MeI in them should pose a negligible risk, which is defined as no more than one excess cancer case in 1 million people.”
That would mean each can or bottle of soft drink would need to contain 3 micrograms or less of 4-MeI.
Consumer Reports’ researchers tested 81 cans and bottles of 12 popular brands of soft drinks from five manufacturers, including Coca-Cola, Pepsi and Goya. The soft drinks were purchased from stores in metropolitan areas of California and New York. In December, the researchers repeated the test with 29 new samples of brands that the initial tests had found contained more than 29 micrograms of 4-MeI per can or bottle.
Here is what the researchers found:
While our study was not large enough to recommend one brand over another, both rounds of testing found that the level of 4-MeI in the samples of Pepsi One and Malta Goya purchased in both locations exceeded 29 micrograms per can or bottle. The products we purchased in California did not have a cancer-risk warning label.
In our initial testing, some of the other brands we bought in California had average levels around or below 29 micrograms per can, but the New York area samples of those same brands tested much higher. In our second test, though, the levels in the New York samples had come down. For example, regular Pepsi from the New York area averaged 174 micrograms in the first test and 32 micrograms in the second. “The fact that we found lower amounts of 4-MeI in our last round of tests suggests that some manufacturers may be taking steps to reduce levels, which would be a step in the right direction,” says Dr. Rangan
On average, three of the brands — Coke, Diet Coke, and Coke Zero — came in under 5 micrograms per can in our tests, a level Consumer Reports’ experts believe is more acceptable. Sprite, a clear soda that was tested as a control, showed no significant levels of 4-MeI.
Responses to study
PepsiCo responded to the results of the Consumer Reports study by pointing out that consumption data has shown that U.S. consumers drink an average of 100 milliliters per day of diet soda — or less than a third of a 12-ounce can. Thus, they believe that they don’t have to put a warning label on Pepsi One products sold in California, even if a single can contains more than 29 micrograms of 4-MeI.
“PepsiCo abides by the law everywhere we do business,” a PepsiCo spokesperson told the Associated Press. PepsiCo also noted that it was reformulating its products to contain lower levels of 4-MeI and that those products would be available nationwide starting in February.
Goya Foods has not, apparently, responded publicly to the Consumer Reports study.
An FDA spokesperson told NPR reporter Allison Aubrey that the agency is “reviewing new data on the safety of 4-MeI” to determine if it needs to take any regulatory action. But “currently,” the spokesperson added, “the FDA has no reason to believe that 4-MeI, at the levels expected in food from the use of caramel colors, poses a health risk to consumers.”
Limiting your exposure
If you want to limit your exposure to 4-MeI, Consumer Reports recommends avoiding food products that contain “caramel color” or “artificial color.”
“Clearly, it’s feasible for manufacturers to reduce levels of 4-MeI in their products right now,” says Rangan. “But until a federal standard is set or there is more transparency in labeling, you may want to read ingredient lists carefully.”