A federal court in West Virginia has denied class certification in a claim brought against DuPont for the alleged release of perfluoroctanoic acid, a substance also known as PFOA or C-8, from its Washington Works plant in Wood County, West Virginia, into drinking water. See Rhodes v. E.I. DuPont De Nemours and Co., 2008 WL 4414720 (S.D. W.Va., September 30, 2008). According to the court, plaintiffs had presented sufficient evidence that exposure to C-8 may be harmful to human health, but what “the plaintiffs misunderstand, however, is what they must show in order for me to certify the class. I cannot certify a class based on some potential harm to the general public, rather, there must be specific injuries to each member of the proposed class. The fact that a public health risk may exist … does not show the common individual injuries needed to certify a class action.”

The court viewed the plaintiffs as seeking primarily injunctive or declaratory relief in the form of a court-supervised medical monitoring program. While the likelihood of the plaintiffs’ success on the merits is not relevant, the court must still engage in “rigorous analysis” to determine whether the proposed class meets the Rule 23 requirements. Gen. Tel. Co. v. Falcon, 457 U.S. 147, 161 (1982). A court may “probe behind the pleadings” to determine whether class certification is appropriate. Id.

A proposed class must be “cohesive” to be certified under Rule 23(b)(2). See Barnes v. Am. Tobacco Co., 161 F.3d 127,143 (3d. Cir.1998). This is particularly so because in a (b)(2) action, unnamed members are bound by the action without the opportunity to opt out. Barnes, 161 F.3d at 142-43. The cohesiveness requirement is similar to but “more stringent” than the commonality requirement of Rule 23(a). See Lienhart v. Dryvit Syst., Inc., 255 F.3d 138,147 n. 4 (4th Cir.2001); Barnes, 161 F.3d at 142-43.

Under West Virgina law, medical monitoring plaintiffs must first show a significant exposure. In a class action, if significant exposure is not a common issue, cohesiveness will be lacking. Exposure is significant if a plaintiff has been exposed to a larger quantity of the toxic substance or has been exposed for a longer duration than the general population. Thus, a plaintiff must be able to demonstrate that his exposure was somehow greater than what would normally be encountered by a person in everyday life.

Here, while the plaintiffs had evidence of the levels of chemical released, that evidence told the court nothing about how the plaintiffs’ C-8 exposure level compares to the level of C-8 exposure experienced by the general population. Evidence of the elevated C-8 concentrations in the named plaintiffs’ blood likewise fails to show common exposure on a class-wide basis. The evidence of the higher C-8 concentration in the named plaintiffs’ blood as compared to the general population suggests only that the named plaintiffs have possibly been “significantly exposed.”  Plaintiffs’ expert testimony did not provide a relevant comparison between the plaintiffs’ exposure and the exposure of the general population. On this record, the general population’s level of exposure to C-8 in their drinking water was unknown.

Under the second pertinent element of the medical monitoring cause of action, a plaintiff must demonstrate that her or she has suffered a significantly increased risk of contracting a particular disease relative to what would be the case in the absence of exposure. Furthermore, a plaintiff must also show that the exposure caused by the defendant was the proximate cause of that increased risk. In other words, the risk must be different and greater than it would have been absent the significant exposure at issue. Common proof of this element is always complicated because the plaintiffs must not only show that the class members have experienced a significantly increased risk but also that: 1) the risk is of a serious latent disease, 2) the defendant proximately caused that risk to each class member, and 3) the risk is significant relative to what it would have been absent the exposure.

The court agreed with DuPont’s argument that the plaintiffs could not show an increased risk of disease with class-wide proof because each class member’s risk of disease will vary based upon: (a) variations in C-8 exposure and dose, and (b) variations in an individual’s background risk of disease absent C-8 exposure. Plaintiffs had to concede that individual characteristics and habits will affect the level of risk experienced by each class member.

In a useful analysis, the court also explained why a regulatory risk assessment cannot and does not support an opinion that each individual class member had experienced a significantly increased risk of disease. In fact, a risk assessment is of limited utility in a toxic tort case, especially for the issue of causation, because of the risk assessment’s distinct purpose. Risk assessments have largely been developed for regulatory purposes and thus serve a protection function in providing a level below which there is no appreciable risk to the general population. They do not provide information about actual risk or causation. See Bernard D. Goldstein & Mary Sue Henifin, Reference Guide on Toxicology in Federal Judicial Center Reference Manual on Scientific Evidence 413 (2d ed. 2000). Because of their appropriately prudent assumptions when there are limited data, risk assessments intentionally encompass the upper range of possible risks. Id.; see also Sutera v. Perrier Group of Am. Inc., 986 F.Supp. 655, 664 (D.Mass.1997) (rejecting regulatory standards as a measure of causation because the purpose of regulatory standards is to reduce public exposure to harmful substances); Allen v. Pa. Eng’g Corp., 102 F.3d 194, 198 (5th Cir.1996)); O’Neal v. Dep’t of the Army, 852 F.Supp. 327, 333 (M.D.Pa.1994) (determining that risk figures based on the EPA’s upper-bound estimates for another chemical are appropriate for regulatory purposes in which the goal is to be particularly cautious but overstate the actual risk and so, are inappropriate for use in determining whether medical monitoring should be instituted.).

Because a risk assessment overstates the risk to a population to achieve its protective and generalized goals, it is impossible to conclude with reasonable certainty that any one person exposed to a substance above the criterion established by the risk assessment has suffered a significantly increased risk. Precautionary measures to keep the general population safer are fundamentally distinct from the medical monitoring cause of action which provides relief to individuals that have already been “injured.”

Finally, on the element of need for medical monitoring, the court again found an absence of cohesion because if the individual nature of the inquiry. Plaintiffs’ expert seemed to assume that a member of the proposed medical monitoring class can have the determination of their particular and individualized diagnostic needs deferred until after the implementation of the medical monitoring protocol. While the proposed medical monitoring program was to be set up based on the “common” exposure, the implementation would be individualized. But while individualized implementation may be standard in public health monitoring programs, the tort of medical monitoring requires that determination to occur prior to a finding of liability. Plaintiffs were thus recommending a public health medical monitoring program rather than medical monitoring addressing tortious injuries to individuals. Plaintiffs thus merely deferred the individual issues that meant the class was not cohesive.