Watchdog group The Center for Environmental Health, announced Wednesday that Pepsi still contains 4-methylimidazole (4-Mel), a carcinogen.

In March, both PepsiC0 (PEP) and Coca-Cola (KO) said they would change their formulas nationwide to no longer include the carcinogen. The change comes after California passed a law that forces drinks with a certain level of carcinogens to have a cancer warning label, reports The Big Story.

The Center for Environmental Health commissioned Eurofins Analystical laboratory to test Coca-Cola and PepsiCo drinks from California and the rest of the country. None of the drinks tested in California contained 4-Mel. Nine out of 10 Coca-Cola products from outside of California didn’t have 4-Mel in them, but all 10 of the PepsiCo drinks contained levels of 4-Mel that were 4 to 8 times higher than what California deems safe, reports The Big Story.

“We applaud Coke,” Michael Green, executive director of the Center for Environmental Health, told The Salt. “Pepsi’s delay is inexplicable. We urge the company to take swift action.”

PepsiCo products will no longer contain 4-Mel starting February 2014, reports The Salt.