California added the compound 4-methylimidazole -- which gives colas their distinctive brown color -- to its list of known carcinogens in 2011, resulting in the need for a cancer warning label on every can of cola sold in the state.
The Center for Science in the Public Interest petitioned the U.S. Food and Drug Administration to ban ammonia-sulfite caramel color from soda and the FDA is reviewing the petition.
"It is important to understand that a consumer would have to consume well over 1.000 cans of soda a day to reach the doses administered in the studies that have shown links to cancer in rodents," Douglas Karas told NPR.
Diana Garza Ciarlante, a Coca-Cola Co. spokeswoman, told NPR the company asked its caramel suppliers to make the necessary manufacturing process modifications to meet the requirements of California.
Ted Nixon, chief executive officer of D.D. Williamson, the world's largest supplier of caramel color, said caramel color now and always has been safe and harmless, but the company has changed the manufacturing process and its new low-4-methylimidazole will meet the demand of his soda clients.