4-MeI is found in two kinds of caramel color that are used to make syrups brown. The chemical has been shown to cause cancer in mice and is a possible human carcinogen.
While Consumer Reports' sample size was not big enough to be able to recommend one brand over another, Consumer Reports Director of Product Safety, Dr. Urvashi Rangan, says how much and how often people eat syrup can increase their cancer risk.
The 4-MeI in syrup is less of a concern than in soft drinks because people tend to consume far less syrup. If you eat syrup twice a week, about a quarter of a cup each time, that would carry close to a negligible lifetime cancer risk. But if you eat syrup daily, as some children do, that cancer risk can increase significantly.
You can also be exposed to 4-MeI from some caramel colors in many other food products. For instance, caramel color is listed as an ingredient in some breads, cereals and barbecue sauce. If it is the type with 4-MeI, that may also increase cancer risk.
You can't tell by looking at a food label which type of caramel coloring is used. So you don't know if it is the type that contains 4-MeI. Consumer Reports has asked the government to regulate the chemical and set limits on how much is allowed in food.