Consumer Reports conducted a study of the possible presence of carcinogens in popular sodas. The study concluded that some sodas contain extremely high levels of 4-methylimidazole (4-mel), which was determined as a potential carcinogen by the International Agency for Research on Cancer (IARC) in 2011.

Soda makers use 4-mel to give sodas their dark brown color, but instead of classifying the chemical as artificial coloring, the companies list 4-mel as “caramel coloring” on the can. California state law requires any food or beverage product with at least 29 micrograms of 4-mel to carry a health warning label. For the most part, 4-mel sodas sold in California stay within approved level of the chemical. But the amount of 4-mel in sodas sold in other states is staggering.

From April to September of 2013, Consumer Reports compared the amount of 4-mel in the same sodas sold in New York and California. One 12 oz. can of Pepsi One had the highest amount of 4-mel at 43.5 mcg in California, exceeding the state-approved level. However, a can of Pepsi One sold in New York contained 195.3 mcg of 4-mel. Similar trends continue in Pepsi’s line of sodas, and the difference in 4-mel levels reflects the differing state regulations.

In New York, Diet Pepsi had 182.7 mcg of 4-mel and regular Pepsi had 174.4 with California levels remaining below or just over the state-approved level.

Consumer Reports conducted the same study again last month and found that 4-mel levels in New York-sold sodas had decreased. The level in New York was still much higher than California-mandated levels at 160.8 mcg, but Diet Pepsi and regular Pepsi were never higher than 33.5 mcg of 4-mel. This drastic reduction points to the manufacturers’ awareness of the potential danger associated with such high levels of a potentially cancer-causing chemical.

Goya Foods Inc., producer of Malta Goya soda, contained the highest amount of 4-mel out of all sodas tested. Initial 4-mel levels in California were the highest at 352.5 mcg. In the December study, Goya only minutely reduced the 4-mel levels as the new California level was 307.5 mcg.  

The presence of the 4-mel begs one to ask whether or not these soda producers had knowledge of the potential risks associated with high levels of 4-mel consumption.

“The soda market remains largely untested, therefore it’s unknown whether or not there could be other potentially harmful chemicals present in soft drinks,“ said Virginia Buchanan with Levin, Papantonio, P.A.

The California Office of Environmental Health Hazard Assessment determined that consuming more than 29 mcg of 4-mel daily poses a one in 100,000 chance in getting cancer. When Consumer Reports released the results to PepsiCo, the company said they don’t have to put warning labels on their products because the California measure is based on per day intake, rather than “per can” intake. Not that many soda drinkers are drinking half of a can and then throwing it away, and certainly most are consuming more than 29 mcg of 4-mel a day.

“We are concerned about both the levels of 4-MeI we found in many of the soft drinks tested and the variations observed among brands,” said Urvashi Rangan, a toxicologist and executive director of the Consumer Reports Food Safety and Sustainability Center. “There is no reason why consumers need to be exposed to this avoidable and unnecessary risk that can stem from coloring food and beverages.”

Josh is a writer and researcher with Ring of Fire. Follow him on Twitter @dnJdeli.