Coca-Cola Co. and PepsiCo Inc. are making changes to the production of an ingredient in their namesake colas to avoid the need to label the packages with a cancer warning.
The changes will not alter the colas' taste, color or formula, according to statements from both companies.
Coke and Pepsi said on Friday that they had asked their suppliers of the caramel coloring in their colas to alter their manufacturing process to meet the requirements of a California ballot initiative aiming to limit exposure to toxic chemicals.
The change is meant to reduce the amount of a chemical called 4-methylimidazole, or 4-MI, which in January was added to the list of chemicals covered by California's Safe Drinking Water and Toxic Enforcement Act of 1986, also known as Proposition 65.
High levels of that chemical have been linked to cancer in animals.
Earlier this week, the Center for Science in the Public Interest (CSPI), a U.S. watchdog group, said it found unsafe levels of the chemical in cans of Coca-Cola, Pepsi-Cola, Dr Pepper Snapple Group Inc.'s Dr Pepper and Whole Foods Markets Inc.'s 365 Cola.
The U.S. Food and Drug Administration said at the time it was reviewing the group's petition but stressed that the drinks were still safe. An FDA spokesman said a person would have to drink "well over a thousand cans of soda a day to reach the doses administered in the studies that have shown links to cancer in rodents".
Shares of Coke and Pepsi were both up 0.4 percent in afternoon trading. The Standard & Poor's 500 index was up 0.5 percent.
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