Coca-Cola was sued Friday in an attempt by parents to force soft drink makers to eliminate ingredients in their products that can form cancer-causing benzene.

The complaint against the soft drink giant came as two other companies settled a lawsuit over benzene, which is linked to leukemia.

Atlanta-based In Zone Brands Inc., maker of BellyWashers, and Preston, Wash.-based TalkingRain Beverage Co. agreed to change ingredients and offer refunds. District of Columbia Superior Court judge Mary Terrell dismissed that case Friday morning.

Similar suits are pending in Kansas, Massachusetts, Florida, California and New Jersey. Plaintiffs added Coke's Vault Zero energy drink to the Kansas lawsuit, which also targets Pepsi's Diet Wild Cherry and Kraft's Crystal Light Sunrise Classic Orange.

Boston lawyer Andrew Rainer, who represents the parents, said the settlement should prod bigger companies to change their ingredients.

"I think if they understand that consumers, and perhaps courts, expect them to eliminate this problem, they will," Rainer said.

BellyWashers are juice drinks that come in reusable bottles featuring Spiderman, Hello Kitty, Scooby Doo and other well-known characters.

The two smaller companies denied that their products caused any harm. But they agreed in April and May to change their ingredients, after the suit was filed. They also agreed to refund or replace drinks made before the switch in ingredients.

In Zone and TalkingRain did not return telephone calls Thursday from The Associated Press. A Coke spokeswoman said officials were reviewing the lawsuit.

Benzene can form in soft drinks containing vitamin C, also called ascorbic acid, and either sodium benzoate or potassium benzoate. Scientists say factors such as heat or light exposure can trigger a reaction that forms benzene in the beverages.

According to the suits, independent laboratory tests found benzene in the drinks at levels above the federal limit for benzene in drinking water.

The Food and Drug Administration found similar results on unidentified brands in sampling from 1995 through 2001 and said it would do more tests.

FDA officials say there is no safety concern and that levels are still relatively low compared with other sources of exposure to benzene.

The soft drink industry agrees and says the amount of soft drinks people consume is much less than the amount of tap water they are exposed to.

As part of the settlement, the companies agreed to pay $35,000 each. Rainer said most of the money will pay legal costs.