Medical Monitoring Class Action Rejected at Pleading Stage

A federal court recently rejected a proposed medical monitoring class action brought by alleged Pepsi drinkers.  The case reminds readers of the importance of the causation element of medical monitoring claims, even though plaintiffs don't need to allege traditional personal injury.  See Riva v. Pepsico, Inc., No. C-14-2929 EMC, 2015 WL 993350 (N.D. Cal.,  3/4/15).

Plaintiffs alleged that two of defendant's beverages contained levels of a chemical, 4–MeI, that caused them to experience an “increased risk of cancer,” specifically bronchioloalveolar cancer.  Plaintiffs sought  medical monitoring as a remedy; specifically, seeking an order requiring Pepsi to establish a “fund from which those individual class members can seek monetary recovery for the costs of actual or anticipated medical monitoring expenses incurred by them.”  Plaintiffs alleged that outcomes in bronchioloalveolar cancer show a clinically significant benefit from early evaluation, detection, and diagnosis. 

California is one of the few states that recognizes a claim for medical monitoring. “In the context of a toxic exposure action, a claim for medical monitoring seeks to recover the cost of future periodic medical examinations intended to facilitate early detection and treatment of disease caused by a plaintiff’s exposure to toxic substances.” Potter v. Firestone Tire & Rubber Co., 6 Cal.4th 965, 1004–05, 25 Cal.Rptr.2d 550, 863 P.2d 795 (1993). In Potter, the California Supreme Court identified five factors in determining the reasonableness and necessity of monitoring:
(1) the significance and extent of the plaintiff’s exposure to chemicals;
(2) the toxicity of the chemicals;
(3) the relative increase in the chance of onset of disease in the exposed plaintiff as a result of the exposure, when compared to
(a) the plaintiff’s chances of developing the disease had he or she not been exposed, and
(b) the chances of the members of the public at large of developing the disease;
(4) the seriousness of the disease for which the plaintiff is at risk; and
(5) the clinical value of early detection and diagnosis.

Based on such factors, the trier of fact decides, “on the basis of competent medical testimony, whether and to what extent the particular plaintiff’s exposure to toxic chemicals in a given situation justifies future periodic medical monitoring.” Id.

Defendant attacked the medical monitoring claim under Rule 12(b)(6), particularly as to the Potter factors related to whether medical monitoring is reasonable and necessary.  Accordingly, the Court examined the allegations related to these critical Potter factors: plaintiff’s exposure to chemicals; the toxicity of the chemicals; and the relative increase in the chance of onset of disease in the exposed plaintiff as a result of the exposure, when compared to (a) the plaintiff’s chances of developing the disease had he or she not been exposed, and (b) the chances of the members of the public at large of developing the disease.

To demonstrate the proximate causation element of the claim, a plaintiff seeking medical monitoring must. among other things, show the significance of her exposure to the toxic chemical. Potter, 6 Cal.4th at 1009, 25 Cal.Rptr.2d 550, 863 P.2d 795; see also Abuan v. Gen. Elec. Co., 3 F.3d 329, 335 (9th Cir.1993) (applying comparable Guam law on medical monitoring). The California Supreme Court has explained, “[e]vidence of exposure alone cannot support a finding that medical monitoring is ... necessary.” Lockheed Martin Corp., 29 Cal.4th at 1108–09, 131 Cal.Rptr.2d 1, 63 P.3d 913. A plaintiff must demonstrate sufficient severity of exposure (its significance and extent) and that “the need for future monitoring is a reasonably certain consequence of [the] toxic exposure” Id. at 1109, 131 Cal.Rptr.2d 1, 63 P.3d 913 (citation omitted).

In this case, Plaintiffs alleged that the chemical had been found to cause lung tumors in laboratory animals -- at a daily dose thousands of times higher than the amount in soda.  Plaintiffs sought to represent a class of all persons who purchased Diet Pepsi or Pepsi One within a four-year period, regardless of consumption amount. What was missing was any allegation of what the significance of this unspecified exposure to the chemical may be; they did not allege what threshold level of exposure allegedly created the increased risk.

Thus, there was insufficient information about the significance and extent of exposure of the class to make the necessary ultimate showing that “the need for future monitoring is a reasonably certain consequence of [the] toxic exposure” Lockheed Martin Corp., 29 Cal.4th at 1109, 131 Cal.Rptr.2d 1, 63 P.3d 913. They simply failed to demonstrate a credible risk of bronchioloalveolar cancer resulting from the human consumption of cola products at the levels alleged by the named plaintiffs. In fact, if anything, the specific scientific finding incorporated into the Complalnt from the mice study was that the amounts of 4–MeI ingested in cola products “may not be significant.”

The Court also found that Plaintiffs had not sufficiently pled their injury or shown the toxicity of 4–MeI. It was not enough thatt 4–MeI is on the Proposition 65 list of known carcinogens, that a toxicologist has stated that there is “no safe level of 4–MeI,” and that advocacy groups have called for the FDA to ban 4–MeI.  The full picture was that “caramel coloring” (the manufacturing of which allegedly produces 4–MEI as a byproduct) is “generally recognized as safe” when used in accordance with good manufacturing practice and as a food color additive. Under the FDCA, the inclusion of “caramel color” as a “color additive” means that the FDA has determined that caramel coloring has not been found “to induce cancer when ingested by man or animal.” 21 U.S.C. § 379e(b)(5)(B).

So while Plaintiffs adequately pled that 4–MeI is toxic and is, generally speaking, a carcinogen—i.e., that 4–MeI is capable of causing cancer, they had not adequately pled their specific theory of injury—an increased risk for bronchioloalveolar cancer sufficient to warrant medical monitoring—“above the speculative level.” Twombly, 550 U.S. at 555. Plaintiffs are not mice, and there was nothing in the Complaint, or the studies incorporated by reference, to suggest that 4–MeI causes this specific form of lung cancer in humans. The same mouse study found no increased cancer in rats and discussed a “species difference” identified in previous studies in terms of how various species absorb, distribute, metabolize, and excrete this very chemical. So this study did not lead to a plausible inference that these Plaintiffs are at increased risk of the specific lung cancer for which they request screening. 

In short, the  Plaintiffs failed to plead factual content to show they had been injured due to a “significant” increase in their risk of lung cancer sufficient to justify medical testing in the absence of any symptoms or present injury. See Potter, 6 Cal.4th at 1008–09, 25 Cal.Rptr.2d 550, 863 P.2d 795. The only factual content supporting the allegation of increased risk of lung cancer came from scientific studies, which had no demonstrable bearing on cancer toxicity for humans at the consumption levels alleged in the case at bar.

A plaintiff seeking medical monitoring must show a need for “specific monitoring beyond that which an individual should pursue as a matter of general good sense and foresight.” Potter, 6 Cal.4th at 1009, 25 Cal.Rptr.2d 550, 863 P.2d 795. In this case, Plaintiffs sought CT scans of their lungs and molecular screening for lung cancer. Lung scans are not needed to remedy injury absent a credible showing that 4–MeI causes this lung cancer in humans.

The Court took the Prop 65 argument head on.  Proposition 65 is broad; its listing embraces “ substances listed as human or animal carcinogens. In other words, “the Proposition 65 list includes chemicals that are known to cause cancer in animals, even though it has not been definitively established that the chemicals will cause cancer in humans.” Baxter Healthcare, 120 Cal.App.4th at 352, 15 Cal.Rptr.3d 430. Furthermore, listing under Proposition 65 only requires one excess case of cancer in an exposed population of 100,000, assuming lifetime exposure at the level in question. Because the burden on a defendant to fund medical screening for thousands, potentially millions, of people is so substantial, the Potter factors serve a critical gatekeeping function, regulating a potential flood of costly litigation; Potter requires a higher level of proof of health risk than that required for inclusion of a substance on the Proposition 65 list.

Finally, the Court addressed the increased risk above background, and other possible sources of exposure.  There can be many possible “causes,” indeed, an infinite number of circumstances which can produce an injury or disease. A possible cause only becomes “probable” when, in the absence of other reasonable causal explanations, it becomes more likely than not that the injury was a result of its action. This is the outer limit of inference upon which an issue may be submitted to the jury. As a result, under California personal injury law the mere possibility of causing cancer alone is insufficient to establish a prima facie case.

The Court said that this concept of causation inheres in the Potter test for the reasonableness of medical monitoring; the trier of fact considers, among other factors, “the relative increase in the chance of onset of disease in the exposed plaintiff as a result of the exposure, when compared to (a) the plaintiff’s chances of developing the disease had he or she not been exposed, and (b) the chances of the members of the public at large of developing the disease.” Potter, 6 Cal.4th at 1009, 25 Cal.Rptr.2d 550, 863 P.2d 795. Consistent with this approach, the Ninth Circuit has affirmed a grant of summary judgment where plaintiffs seeking medical monitoring failed to introduce facts regarding the “quantitative (or even qualitative) increased risk to individuals.” Abuan, 3 F.3d at 335.

The Complaint admitted that there are many sources of consumption of 4–MeI, including “baked goods, confectionary, extruded breakfast cereals, instantaneous soups, and dark beers” as well as “soy sauce and coffee.” The many alternative sources of 4–MeI was problematic to the establishment of any causation between the Pepsi products at issue and the Plaintiffs’ alleged consumption of 4–MeI “at or above certain threshold levels” (whatever those threshold levels, if any, may be). The many sources of 4–MeI prevented these Plaintiffs from satisfying the third Potter factor.

Where the pleadings reveal so many commonly consumed foods with similar levels of a chemicaI, it is implausible to conclude that any alleged increased risk of cancer is “more likely than not” caused by drinking/using one product, said the Court.  As a result, the Plaintiffs’ claims were dismissed. See Twombly, 550 U.S. at 557 (“something beyond the mere possibility of loss causation must be alleged”).



Two New Studies on the Potential Risks of Nanotechnology

Two studies have just recently been published describing some potentially important features of a promising form of nanotechnology. Articles in the Journal of Toxicological Sciences and Nature Nanotechnology have reported results of experiments in which some multi-walled carbon nanotubes seem able to induce in mice a response similar to that induced by certain asbestos fibers.

Many readers of MassTortDefense know that nanotechnology refers to a new field of technology that seeks to manipulate and control products, really matter, on the atomic and molecular scale, typically 100 nanometers or smaller. To give some sense of scale, one nanometer is one billionth, or 10-9 of a meter. A nanometer compared to a meter is the roughly the same ratio as that of a baseball to the size of the Earth. Or another analogy, a nanometer is the length a man's whiskers grow in the time it takes him to lift his razor to his face to shave.

Two main approaches are used in nanotechnology. In a bottom-up approach, materials and devices are built from molecular components which more or less assemble themselves chemically. In a top-down approach, nano-objects are de-constructed from larger entities. While scientists speculated about nanotechnology in the 1950’s, it is really the modern generation of analytical tools such as the most powerful atomic microscopes which allow the potential deliberate manipulation of nanostructures.

What is so fascinating, and potentially useful, about nanotechnology is that normal sized physical phenomena may be altered as the size of the product decreases. Some features may be enhanced, even dominant at smaller sizes. Moreover, a number of physical, mechanical, electrical, or other properties can change as the size of the particle decreases. As the ratio of surface area to volume changes, the mechanical, thermal and catalytic properties of materials may be altered. Third, novel mechanical properties of nanosystems have also been identified in the lab. For example, opaque substances like copper become transparent; inert materials like platinum become catalysts; some stable substances like aluminum become combustible. Similarly, some solids turn into liquids even at room temperature.

Examples of nanotechnology include new polymers, and computer chips. Nanotechnologies have already found commercial application in suntan lotions, cosmetics, protective coatings, and stain resistant apparel. Significant research is being done on the targeted delivery of drugs to tumors or infections sites using nanotechnology.

Potential Issues
As with any new technology, questions about potential health and environmental risks have been raised. The unique properties of nano-materials make them at once attractive to product makers, but also raise questions about whether conventional thinking about product safety are adequate. For example, the enhanced catalytic activity of certain nano-materials may raise potential questions about their theoretical interaction with biomaterials. Moreover, as seen in the two new studies, the size of the particles raises issues in their own right.

Carbon Nanotubes
In both studies, suspensions of carbon nanotubes were injected into the abdominal cavities of mice, and the results compared against asbestos as a positive control for mesothelioma. Carbon nanotubes are generally made from sheets of graphite no thicker than an atom—about a nanometer, or one billionth of a meter wide—and formed into cylinders, with the diameter varying from a few nanometers up to tens of nanometers. They are excellent conductors of electricity. Carbon nanotubes can also be used to reinforce polymers to create very strong plastics. Carbon nanotubes show promise as building blocks for computer chips that are smaller and faster than those made of silicon. Economists predict that the market for carbon nanotubes will grow to more than $1 billion by 2014.

The Studies
In the JTS study, Atsuya Takagi, et al., “Induction of mesothelioma in p53+/− mouse by intraperitoneal application of multi-wall carbon nanotubes,” J. Toxicol. Sci., Vol. 33: No. 1, 105-116 (2008), researchers tested the hypothesis that due to their fibrous shape and embedded iron content multi-walled carbon nanotubes would have carcinogenic potential similar to asbestos. Blue asbestos (crocidolite), which is known to cause mesothelioma, and fullerene aggregates, which were hypothesized not to cause mesothelioma, were also studied so the results could be compared. Examination of the mice from 10 days to 25 weeks after exposure revealed that the MWCNT and asbestos both resulted in the formation of cancerous lesions that the authors saw as consistent with the disease mesothelioma. (The mice exposed to the other control did not develop these lesions.) The authors suggest that these results point out the possibility that carbon-made fibrous or rod-shaped micrometer particles may share the carcinogenic mechanisms postulated for asbestos. The researchers suggest that the aspect (length/width) ratio and biopersistence of MWCNT may be important factors in understanding their effect on the body.

In the NN study, C. Poland, et al., Carbon nanotubes introduced into the abdominal cavity display asbestos-like pathogenic behavior in a pilot study, Nature Nanotechnology, Published online: 20 May 2008 (doi:10.1038/nnano.2008.111), researchers tested the hypothesis that long straight nanotubes act like long straight asbestos fibers and can cause injury like that seen in mesothelioma. They reported that exposing the mesothelial lining of the body cavity of mice, as a surrogate for the mesothelial lining of the chest cavity, to long multiwalled carbon nanotubes results in asbestos-like, length-dependent, pathogenic behavior. They used various materials for comparison: long, straight MWCNT, short tangled MWCNT, long-fiber amosite asbestos, short-fiber amosite, and a nonfibrous nanoparticulate carbon black material as a control. Tissue samples measured at 7 days were examined for the formation of scar-like lesions called granulomas that often typify the body's response to long fibers. They observed that the mice exposed to the long straight fiber asbestos and the long straight MWCNT showed the presence of inflammatory proteins, cells and granulomas, but not the other substances.

What to Make of the Results
The two studies suggest a need for a careful ongoing assessment of the potential for MWCNT to cause injury. They do not prove or even strongly suggest that nanotubes can cause cancer. The route of exposure is a crucial aspect of toxicology and here it was injection and not inhalation; neither study addresses the question whether inhalation of MWCNT leads to serious health effects like asbestos. It is not clear that carbon nanotubes will become airborne and be inhaled, or whether, if they do reach the lungs, they can get to the mesothelium to cause the effects seen here in mice. Another recent study showed that when mice inhaled nanotubes their lungs returned to normal within one or two months.

Of course, both studies are animal studies, and one used mice that have been specially bred to be susceptible to cancer. Measuring dose is not necessarily easy with nanomaterials, and it is unclear what constitutes an appropriate dose in mice to correlate with human exposures and risk. It is unclear that any humans are or can be exposed to MWCNT in quantities sufficient to induce the effect seen here in mice. If there is a potential hazard, there will be no disease if workers are not overly exposed to long nanotubes. Risk is composed of two parts – hazard and exposure.

Confounding factors involved include the presence of metals, like iron, in the nanotube samples. The JTS study explicitly could not rule out the iron contaminant within the MWCNT samples as the agent responsible for promoting the formation of the cancerous lesions.

Given the importance of this new field, and this new type of product, counsel involved in toxic tort and product liability  litigation will want to keep a close eye on the developing science.

New BPA Study Released

At MassTortDefense we know the importance of well done scientific studies on causation, whether they be epidemiological studies of relevant populations, in vitro studies, or animal toxicology. While we don’t make a habit of posting about individual studies, BPA has been so much in the news, we thought it worth a mention of a recent animal study just published in the journal Toxicological Sciences. Tyl, et al., Two-Generation Reproductive Toxicity Study of Dietary Bisphenol A (BPA) in CD-1 (Swiss) Mice, with an abstract that can be found hereToxicological Sciences is the official journal of the Society of Toxicology and publishes peer-reviewed, hypothesis-driven, original research articles in all areas of toxicology.

The two-generation study exposed mice to a wide range of doses of bisphenol A, and found the chemical did not cause reproductive or developmental harm. The study was funded by the American Chemistry Council, and conducted under the oversight of the EU Bisphenol A Steering Group. That group, which included reproductive and developmental toxicologists from several countries, also had representatives of the World Wildlife Fund on behalf of nongovernmental organizations. The group impacted the study's design and the specific protocols used, and commented on the draft report analyzing the results.

The study was designed to fill in some of the blanks some felt existed in previous animal studies, by utilizing a species of mice particularly sensitive to hormone disruption; exposing the mice to the low doses where some say reproductive and developmental harm would occur; exposing the mice to the chemical in their feed, to mimic route of exposure; and keeping more of the mice alive longer than is typically done.

Clearly the debate over BPA will continue.