An Orange County woman has filed suit against PepsiCo Inc., alleging that the food and beverage company failed to warn consumers that its diet soda, Pepsi One, contains a cancer-causing component.
Kelly Ree contends in the lawsuit that Pepsi One contains a dangerous level of 4-methylimidazole, or 4-MEI, which has been shown to cause cancer in laboratory mice. She said the company was required to warn consumers of the danger under California's Proposition 65 but failed to do so.
"Plaintiff would not have purchased the product had she known that it contained 4-MEI well in excess of Proposition 65 guidelines," the lawsuit contends.
Ree said she purchased the soda in 2012. The lawsuit seeks certification as a class-action, a step that would include potentially thousands of consumers as plaintiffs.
PepsiCo did not immediately respond to a request for comment.
The chemical is formed during the production of certain caramel-coloring agents used in many foods and beverages. It is found in colas, beers, soy sauces, breads, coffee and other products, according to California's Office of Environmental Health Hazard Assessment.
Studies published in 2007 by the federal government's National Toxicology Program showed that long-term exposure to 4-MEI led to increases in lung cancer in mice. As a result, 4-MEI was added to the list of carcinogens that must be disclosed under California law.
Coca-Cola Co. and PepsiCo said they were altering how they made cola beverages to reduce the amount of 4-MEI and avoid the disclosure requirement.
But last month, Consumer Reports reported that its testing found that Pepsi One contained in excess of 29 micrograms of 4-MEI per serving.
In her lawsuit, Ree seeks unspecified monetary damages, plus an injunction requiring PepsiCo to either reduce the amount of the chemical in Pepsi One or include a warning on product labels.
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