Coca-Cola Co. has been hit by a lawsuit claiming some Coke products contain unsafe levels of benzene.

The lawsuit, issued in Kansas on Friday (25 August) alleges that tests on Coke's Vault Zero beverage found 13 parts per billion of benzene, considerably higher than the US Environmental Protection Agency's 5ppb limit for drinking water.

Coke's Vault Zero was added to the lawsuit alongside PepsiCo's Diet Wild Cherry and Kraft Food's Crystal Light Sunrise Classic Orange.

Coke has dismissed the claims, telling local reporters that the lawsuit is less about consumer safety and more about "lining lawyer's pockets".

"There is no supporting documentation to prove how these lawyers conducted these tests," a Coke spokesperson told reporters. "Their own press release indicates that they have abused the product with heat prior to testing."

Two other soft drinks companies, In Zone Brands and Talking-Rain Beverage, have settled separate lawsuits on the level of benzene in their products. The companies agreed to change their ingredients and to offer refunds to customers on the original products. Both companies denied, however, that their products caused any harm.

The issue of benzene in soft drinks blew up again in March, when the US Food and Drug Administration said that the presence of benzene - linked with leukaemia - at low ppb was not an imminent health hazard.