Nearly half of Americans drink soda daily, an average of two-and-a-half glasses a day. Much of it contains caramel color -- two types of which can contain a potentially carcinogenic by-product.
"There is a risk in there that consumers should be informed about," said Urvashi Rangan, PhD, with Consumer Reports.
Consumer Reports recently tested 110 samples of soft drinks bought in the New York area and California, including iced tea, root beer, colas, and a non-alcoholic malt drink. The chemical, 4-MEI -- which a government study found caused cancer in mice -- showed up at varying levels across all brands tested that contained caramel coloring.
"Some sodas were actually fairly low in their levels of 4-MEI, whereas some soft drinks were extremely high," said Rangan.
The highest levels of 4-MEI Consumer Reports found were in Malta Goya and in Pepsi One. All the Coca Cola samples were far lower.
"The limitation in this study is a very small sample size, so we can't really draw conclusions about any one given brand," said Rangan.
However, Consumer Reports says people should know if the caramel color they are drinking contains a potential carcinogen. Two types don't, but the label simply says caramel color or artificial color, so you don't know the type you're getting.
"Consumers who want to avoid this hazard should avoid caramel color in sodas altogether," said Rangan. Check the labels on other types of foods too, including barbecue sauce, syrups, bread and beer.
There are currently no federal limits on 4-MEI in food products, but Consumer Reports is calling on the Food and Drug Administration to set limits and to require more explicit labeling.
Consumer Reports told PepsiCo and Goya about its findings. Goya says it is looking into the matter. PepsiCo says its products sold in California meet that state's regulations for 4-MEI and it is voluntarily applying those same standards to the rest of the country within the next month.
The FDA's current position is that 4-MEI does not pose a risk to consumers. Consumer Reports says it plans on turning over its findings to the FDA. The consensus held by many in the scientific community is this chemical doesn't currently pose a health hazard at the levels humans are likeliest to be exposed.