PepsiCo Inc has been filed a lawsuit by an Orange County native who claimed that the food and beverage company did not put in the cancerous ingredient on its diet soda, Pepsi One, the Los Angeles Times said in a report. Kelly Ree insisted that Pepsi One failed to disclose the danger of drinking the diet soda, which contains purportedly alarming levels of 4-methylimidazole, or 4-MEI. According to the lawsuit, the chemical had been shown in laboratory studies to cause cancer in experimental mice. Ree invoked the Proposition 65 legislation, which requires companies to disclose pertinent information about ingredients in its manufactured products.

The LA Times said Ree purchased the diet soda in 2012. Ree is applying for group status, which would demand a lot of remuneration as damages from thousands of consumers.

Part of the lawsuit read, "Plaintiff would not have purchased the product had she known that it contained 4-MEI well in excess of Proposition 65 guidelines."

According to the California's Office of Environmental Health Hazard Assessment, the chemical is a by-product during the process of producing caramel-coloring agents that are used in several food and beverages like soy sauces, breads, coffee and other products aside from colas. LA Times also pointed to several 2007 studies conducted by the US government's National Toxicology Program, which showed that long-term exposure to the carcinogen found in colas like Pepsi One increases lung cancer in laboratory mice. This, said the studies, resulted to the addition of 4-MEI as one of the carcinogens needed to be disclosed on products based on the California statute/

Ree said in the lawsuit that she is seeking an injunction that would require PepsiCo to disclose the effects of 4-MEI in their diet sodas or reduce the ingredient into industry-accepted levels. The plaintiff is also seeking seeks unspecified monetary damages aside from the injunction, the lawsuit read.