Soft drink ingredient linked to cancer

Consumers are being exposed to an "avoidable and unnecessary cancer risk" from an ingredient being added to soft drinks, according to a new study.

Researchers, led by a team at the Johns Hopkins Center for a Livable Future (CLF) analysed the risk of 4-methylimidazole (4-MEI) - a possible human carcinogen formed during the manufacture of some types of colouring.

While they were unable to recommend one brand over another, or draw conclusions about specific brands, the results did show that levels of 4-MEI can vary greatly.

This unnecessary exposure poses a threat to public health and raises questions about the continued use of caramel colouring in soda.

• Keeve Nachman, CLF

Some brands changed their recipes in 2012 so they could avoid being forced to put a cancer warning on their bottles in California. At the time, leading brands said that 4-MEI which had previously been linked to cancer threats in rats and mice, posed no threat to humans.

No new rules were brought in for Europe and therefore the recipes were reported to have stayed the same. However, the new study will increase concerns.

This new analysis underscores our belief that people consume significant amounts of soda that unnecessarily elevate their risk of cancer over the course of a lifetime," says "We believe beverage makers and the government should take the steps needed to protect public health.

• Urvashi Rangan, Food Safety and Sustainability Center

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