Mercury Warnings on Tuna Under Prop. 65 Not Required
A California appeals court has determined that canned tuna sold in the state does not need a mercury warning label under Proposition 65 (Prop. 65) for reproductive toxicity because the mercury is naturally occurring and thus falls within a Prop. 65 exemption. People ex rel. Brown v. Tri-Union Seafoods, LLC, No. A116792 (Cal. Ct. App., decided March 11, 2009). A trial court ruled in 2006 that the labels were not required because (i) federal law preempts state action on methylmercury in fish; (ii) the trace levels of mercury in canned tuna were too insignificant to require warnings; and (iii) the mercury is naturally occurring. Further information about that ruling appears in issue 170 of this Update.
The appeals court specifically considered and based its ruling on the last basis for decision only, finding that substantial evidence supported the trial court’s determination as to the source of mercury contamination in fish. According to the defendants’ experts, deemed more credible by the trial court, volcanic activity contributes significantly to the presence of mercury in the environment, and testing has shown that the largest source of mercury in fish is likely coming from deep ocean floor vents.
Because most of its opinion addressed the “battle of the experts” that occurred at trial and involved important public health issues involving a chemical known to cause serious neurotoxic effects in fetuses, the court lamented “whether the truth about complex. threshold scientific issues encompassed within Proposition 65—such as whether methylmercury in fish is naturally occurring—is best derived by application of the substantial evidence rule to the testimony and opinions of dueling experts serving under partisan commitments.”
By expressly limiting the basis for its decision, the court suggested that other “potential scenarios” could lead to a viable renewed Prop. 65 claim related to canned tuna. “For example, the Office of Environmental Health Hazard Assessment (OEHHA), the lead agency designated by the Governor to implement the provisions of Proposition 65, could amend the regulations to except the presence of methylmercury in canned tuna from the naturally occurring rules. Similarly, the determination of whether methylmercury in tuna is naturally occurring could be lodged with the OEHHA and its scientific advisors, rather than left to dueling expert witnesses in a trial court setting.” The court also opined that scientific research, which is not static, “can easily become dated and outmoded as science develops and new research explains the phenomena in question more thoroughly and completely.”
Meanwhile, a California TV personality reportedly conducted her own “unscientific” mercury test by eating 20 5-ounce cans of albacore tuna over 20 days. At the outset of the experiment, her blood mercury level measured 4 micrograms per liter. Ten days later, it measured 8.9 micrograms per liter; and by day 20, it measured 17.2 micrograms per liter. Her physician reportedly told her to stop the experiment, noting that patients with high blood mercury levels “get body aches, joint pain, muscle aches, head ache, trouble sleeping, troubles with thinking and memory, stomach upset.” The reporter did not apparently experience these effects. Dr. Jane Hightower also cautioned that a pregnant woman with levels above 14 or 15 “stands a chance of knocking IQ points off her child’s brain.” See cbs5.com, March 6, 2009
