An environmental group said Wednesday that the caramel coloring used in Pepsi still contains a worrisome level of a carcinogen, even after the drink maker said it would change its formula.

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 carcinogens come with a cancer warning label. The changes were made for drinks sold in California when the law passed.