In March, PepsiCo Inc and Coca-Cola Co both said they would adjust their formulas nationally after California passed a law mandating drinks containing a certain level of carcinogen come with a cancer warning label.
The changes were made for drinks sold in California when the law passed. The chemical is 4-methylimidazole, or 4-Mel, which can form during the cooking process and, as a result, may be found in trace amounts in many foods.
Watchdog group The Center for Environmental Health found via testing that while Coke products no longer test positive for the chemical, while Pepsi products sold outside of California still do.
Pepsi said its caramel coloring suppliers are changing their manufacturing process to cut the amount of 4-Mel in its caramel.
That process is complete in California and will be finished in February 2014 in the rest of the country. Pepsi said it will also be taken out globally, but did not indicate a timeline.
Meanwhile, the company said the FDA and other regulatory agencies around the world consider Pepsi's caramel coloring safe. Coca-Cola said it has transitioned to using a modified caramel in US markets beyond California that does not contain Mel-4, so it wouldn't have to have separate inventory of products for different locations.
It also said all of its products, whether they have the modified caramel or not, are safe. The watchdog group Center for Environmental Health said it commissioned Eurofins Analystical laboratory in Metairie, La., to test Coke and Pepsi products from California in May and from across the country in June.
The lab did not find the chemical in California products. And it found no 4-Mel in nine out of 10 Coke products outside of the state.
But it found levels of 4-Mel that are 4 to 8 times higher than California safety levels in all 10 Pepsi products purchased outside California, according to the Center for Environmental Health.
Trace amounts of 4-Mel have not been linked to cancer in humans. The American Beverage Association said that California added the coloring to its list of carcinogens with no studies showing that it causes cancer in humans.
It noted that the listing was based on a single study in lab mice and rats. The Food and Drug Administration has also said that a consumer would have to drink more than 1,000 cans of soda a day to reach the doses administered that have shown links to cancer in rodents.
Coca-Cola and PepsiCo account for almost 90 percent of the soda market, according to industry tracker Beverage Digest.