Recent testings revealed that cans of  Pepsi One may contain high levels of a potential carcinogen called d 4-methylimidazole (4-MeI), Fox News reports.

Consumer Reports tested 81 cans and bottles of popular soft drinks purchased in New York and California between April and September 2013. The researchers then retested any brands that initially tested as containing over 29 micrograms of 4-MeI per can or bottle.

Both rounds of testing revealed that Pepsi One and another soft drink called Malta Goya contained more than 29 grams of 4-MeI per can or bottle.

Testing also showed that Coke, Diet Coke and Coke Zero contained less than 5 micrograms of 4-MeI, which Consumer Reports considered acceptable. Additionally, Sprite showed no significant levels of the chemical.

When asked to comment, PepsiCo told Consumer Reports that California’s Proposition 65 requirement is based on exposure to 4-MeI per day – not per can. PepsiCo also cited data stating that most consumers drink less than a third of a can of soda per day.

According to Consumer Reports, the FDA are conducting their own testing.