A lawsuit filed Friday in Kansas against Coca-Cola Co. alleges that the soft drink maker included ingredients in its beverages that could form cancer-causing benzene.

On the same day, two U.S. companies announced they will eliminate similar ingredients from their children's beverages.

A Coca-Cola spokesman said the U.S. Food and Drug Administration  concluded its products did not pose a threat to consumer safety.

"[The FDA] has closely reviewed beverages for the presence of benzene in soft drinks several times in the past and each time has found no public health issue," said spokesman Ray Crockett.

Concerned parents had filed a lawsuit against In Zone Brands Inc., based in Atlanta, and Washington-based TalkingRain Beverage Co., accusing the companies of using ingredients that can form benzene.

The companies settled the lawsuit, saying they will change how they make their BellyWashers juice.

The beverage makers maintained that their products were harmless. They're also offering a refund or replacement to consumers before the switch is implemented.

Canadian investigation

Benzene, a known carcinogen to humans, can be formed when Vitamin C is combined with sodium benzoate or potassium benzoate. Factors such as heat or light exposure can prompt a reaction forming benzene in the beverages.

Independent lab tests found benzene in the BellyWashers beverages at levels above the U.S. limit for benzene in drinking water, according to the lawsuit.

Prompted by a recent U.S. study that investigated the levels of benzene in beverages, Health Canada and the Canadian Food Inspection Agency launched their own investigation this year.

In May 2006, the Canadian agencies released the findings of their study. In a test of 118 soft drinks, low-alcohol beverages and cocktail mixes, four products were found to exceed the government-imposed limit of five micrograms per litre.

The makers of Rose's Cocktail Infusion cranberry twist, Mr & Mrs T Margarita Mix mix, Kool-Aid Jammers "10" cherry flavour and Kool-Aid Jammers "10" tropical punch flavour agreed to change their products to conform with the prescribed benzene limit.

The Canadian researchers concluded that for the majority of product samples tested, benzene was not detected or was present in trace amounts too small to reliably measure.

With files from the Associated Press