SAN FRANCISCO (CN) - Diet Pepsi and Pepsi One drinkers are not entitled to medical monitoring because there is no evidence that a carcinogen found in the drinks causes cancer in humans, a federal judge ruled, dismissing the class action claims.
Paul Riva and Danielle Ardagna claimed Diet Pepsi and Pepsi One contained carcinogenic 4-methylimidazole (4-MeI), a byproduct of caramel coloring, at levels that caused them to experience an increased risk of bronchioloalveolar cancer, an uncommon form of lung cancer.
Riva and Ardagna were originally part of a consolidated class action against Pepsico, which claimed that Pepsi products' levels of 4-MeI were unhealthy. Interim lead counsel decided not to allege any personal injury or medical monitoring claims in the consolidated amended complaint, so the Riva action was severed and allowed to proceed on its own.
On Wednesday, U.S. District Judge Edward Chen dismissed the Riva case after finding no basis for the claim of entitlement to medical monitoring.
"There is no plausible inference that 4-MeI causes bronchioloalveolar cancer in humans. The threshold levels of exposure that lead to enhanced risk of disease have not been identified. And many other common foods contain similar or higher levels of 4-MeI than the Pepsi products at issue," Chen ruled.
The state placed 4-MeI on its Proposition 65 list of carcinogens in 2011, after the National Toxicology Program found that it caused lung tumors in laboratory animals, according to the state's Office of Environmental Health Hazard Assessment .
California law requires disclosure of the presence of the carcinogen at levels above 29 micrograms per day.
Testing by Consumer Reports in 2013 found that Diet Pepsi sold in California contained an average of 30.5 micrograms per can and Pepsi One contained an average of 43.5 micrograms, according to Riva's lawsuit.
Riva claimed he drank Pepsi One two to three times every week, while Ardagna said she drank three to four cans of Diet Pepsi per day.
Riva and Ardagna asserted claims for negligence, strict liability based on defective design and strict liability based on failure to warn, and sought medical monitoring as a remedy for all three claims.
Instead of seeking to certify a class for the entire action or for the damages portion of their case, Riva and Ardagna contemplated a two-step process in which they would seek to certify certain liability issues and issues pertaining to remedies, such as whether medical monitoring is warranted, and then envisioned that class members would "individually litigate their damages" from the fund created through the class process.
However, Chen dismissed the entire action without leave to amend, finding that Riva and Ardagna did not allege a causal connection between consuming the Pepsi products and an increased risk of developing lung cancer in humans.
Their complaint provided no context as to what level of exposure to the carcinogen would increase the alleged risk in humans, nor did Riva cite any studies suggesting that 4-MeI would cause bronchioloalveolar cancer in humans, the judge found.
"(T)he Riva plaintiffs have alleged that mice experience increased risk of harm of a specific form of lung cancer at very high exposures to 4-MeI; but they have not alleged facts to show that humans experience the same increased risk, particularly at the exposures alleged," Chen wrote.
One of the studies cited by Riva suggested that the cancer the mice experienced would not result in other species, Chen pointed out.
"The Riva plaintiffs have effectively invited the court to engage in an 'ingenious academic exercise in the conceivable to explain how defendants' actions caused their injury.' That is not sufficient to establish plaintiffs' standing to bring the instant case seeking medical monitoring for bronchioloalveolar cancer," the judge ruled.
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