Pepsi’s caramel coloring additive contains high levels of a possible carcinogen called 4-methylimidazole (4-MeI). Under California’s Proposition 65 law any food or beverage that exposes people to 29 micrograms or more per day is supposed to carry a health warning label.
The 29 micrograms was determined by the California Office of Environmental Health Hazard Assessment as it’s at that level that the risk is one in 100 000 for developing cancer. According to Consumer Reports testing, one can of Pepsi contains 174 micrograms of 4-Mel! Even at 29 micrograms the report concludes it’s still too high.
“Consumer Reports’ experts think even that risk 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. And even if your choice of soft drink contains half that amount, many people have more than one can per day,” says Rangan. “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.” To meet that risk level, Consumer Reports’ experts say a soft drink would need to contain about 3 micrograms or less per can.”