A recent ruling in California US District Court will severely curtail the ability of plaintiffs to bring tort actions based on exposure to chemicals listed under California’s Proposition 65 (Prop 65) as chemicals known to cause cancer or birth defects.

In a March 2015 opinion in Riva v. Pepsico, Inc. case, Case No. C-14-2020 EMC, Judge Edward M. Chen of the United States District Court for the Northern District of California granted defendant Pepsico’s motion to dismiss plaintiffs’ claims for strict liability-design defect, strict liability-failure to warn, and negligence based on their exposure to levels of 4-methylimidazole (4-Mel) in Pepsi soft drinks that exceeded the levels triggering a warning under Prop 65. The plaintiffs claimed that this exposure had caused an increase in their risk of cancer, requiring medical monitoring.

Relying in part on a previous case decided by the California Supreme Court, Potter v. Firestone Tire and Rubber Co. (1993) 6 Cal.4th 965, the Court found that the plaintiffs had failed to establish that they had standing to bring their medical monitoring case. In reaching this determination, the Court examined a series of factors annunciated in Potter, including the 1) the significance and extent of the plaintiffs’ exposure to chemicals; 2) the toxicity of the chemicals; and 3) the relative increase in the chance of onset of disease as a result of the exposure. These factors led the Court to conclude that plaintiffs’ claim of an increase of risk of injury was speculative.

In granting the motion to dismiss, the Court took judicial notice of three scientific articles relied on in plaintiffs’ complaint, which discussed studies that showed that the ingestion of massive amounts of 4-Mel caused lung tumors in rats. The Court found that these studies did not show that humans experienced the same risks when ingesting 4-Mel, particularly at the dramatically lower levels found in Pepsi soft drinks. Indeed, the studies specifically stated that the findings could not be extrapolated to humans. Although the Court acknowledged that 4-Mel was listed by the State of California as a carcinogen under Prop 65, the Court also noted that Prop 65 is extremely broad and lists substances that only cause cancer in animals.

Finally, the Court noted that, under California law, in a personal injury action, the mere possibility that a substance could cause cancer was insufficient to support the plaintiffs’ claims. Rather, causation must be shown between the exposure and the harm. Taking judicial notice of the articles referenced by the plaintiffs, the Court noted that there are many items with levels of 4-Mel similar to that found in the soft drinks, such as coffee, baked goods, breakfast cereals, and soap, preventing a finding that any significant increase in risk was specifically due to exposure to 4-Mel from soft drinks, especially, again, given the relatively low levels.

Ultimately, the Court found that there was no possible way for the plaintiffs to cure the deficiencies in the complaint. The Court specifically rejected the plaintiffs’ last ditch argument that an expert report could cure the defects, because of “the lack of any factual content to show that Mel-4 causes…cancer in humans and the failure to plead that the levels of consumption alleged herein are sufficient to trigger credible risk of such cancer” and the plaintiffs acknowledgement that they were not aware of any other additional scientific studies on this topic.

This ruling is a major victory for the defense bar and will prevent plaintiffs from simply relying on a Prop 65 listing to support claims that they are entitled to damages based on chemical exposure.