United States District Court, W.D. Pennsylvania
JOY FLOWERS CONTI, Chief District Judge.
Before the court are expert challenges filed by plaintiffs Michael and Jessica Hartle and their minor daughter, "GH" (collectively "plaintiffs"), and defendant FirstEnergy Generation Corporation ("FirstEnergy" or "defendant"). This case involves FirstEnergy's Bruce Mansfield Power Plant ("Bruce Mansfield"), a coal-fired electric generating facility located along the Ohio River in Shippingport, Pennsylvania. The plaintiffs allege that on July 22, 2006, Bruce Mansfield discharged air pollution in the form of "black rain, " a dark-colored sooty material that fell to the ground near the plant. The plaintiffs allege that GH was playing outside during the black rain event and was exposed to toxins-particularly thallium, arsenic, and other hazardous metals-in the sooty residue, which caused her to suffer alopecia and other adverse health effects.
The parties conducted extensive fact and expert discovery in this case and two other cases consolidated for discovery purposes ( Patrick v. FirstEnergy Generation Corp., Civil No. 08-1025, and Price v. FirstEnergy Generation Corp., Civil No. 08-1030). This memorandum opinion addresses the parties' motions to exclude the expert testimony of Michael Gochfeld, MD ("Gochfeld"), ECF No. 106; Peter Valberg, PhD ("Valberg"), ECF No. 120; James S. Smith, PhD ("Smith"),  ECF No. 102; and Allister Vale, PhD ("Vale"), ECF No. 122. These experts opine on toxicology and medical issues related to the causation of GH's medical conditions. The motions to exclude these experts are fully briefed, and the court heard testimony and argument on October 16, 2013.
II. Legal Standards
Federal Rule of Evidence 702 governs the admissibility of expert testimony and states:
A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if:
(a) the expert's scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue;
(b) the testimony is based on sufficient facts or data;
(c) the testimony is the product of reliable principles and methods; and
(d) the expert has reliably applied the principles and methods to the facts of the case.
FED. R. EVID. 702. Under the seminal case of Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), district courts must act as gatekeepers to "ensure that any and all scientific testimony or evidence admitted is... reliable." Id. at 589. The United States Court of Appeals for the Third Circuit explained that Rule 702 "embodies a trilogy of restrictions" that expert testimony must meet for admissibility: qualification, reliability and fit. Schneider ex rel. Estate of Schneider v. Fried, 320 F.3d 396, 404 (3d Cir. 2003). The party offering the expert testimony has the burden of establishing each of these requirements by a preponderance of the evidence. In re TMI Litig., 193 F.3d 613, 663 (3d Cir. 1999).
An expert witness's qualification stems from his or her "knowledge, skill, experience, training, or education." FED. R. EVID. 702. The witness therefore must have "specialized expertise." Schneider, 320 F.3d at 405. The court of appeals interprets the qualification requirement "liberally, ' holding that a broad range of knowledge, skills, and training qualify an expert as such.'" Calhoun v. Yamaha Motor Corp., U.S.A., 350 F.3d 316, 321 (3d Cir. 2003) (quoting In re Paoli R.R. Yard PCB Litig., 35 F.3d 717, 741 (3d Cir. 1994)). When evaluating an expert's qualifications, district courts should not insist on a certain kind of degree or background. Robinson v. Hartzell Propeller Inc., 326 F.Supp.2d 631, 667 (E.D. Pa. 2004). An expert's qualifications are determined with respect to each matter addressed in the proposed testimony. Calhoun, 350 F.3d at 322 ("An expert may be generally qualified but may lack qualifications to testify outside his area of expertise."). "While the background, education, and training may provide an expert with general knowledge to testify about general matters, more specific knowledge is required to support more specific opinions." Id.
In Daubert, the Supreme Court stated that the district court's gatekeeper role requires "a preliminary assessment of whether the reasoning or methodology underlying the testimony is... valid and of whether the reasoning or methodology properly can be applied to the facts in issue." Daubert, 509 U.S. at 592-93. While the Court noted in Daubert that district courts were permitted to undertake a flexible inquiry into the admissibility of expert testimony under Rule 702, the court of appeals has enumerated the following eight factors that a district court may examine:
1. whether a method consists of a testable hypothesis;
2. whether the method has been subjected to peer review;
3. the known or potential rate of error;
4. the existence and maintenance of standards controlling the technique's operation;
5. whether the method is generally accepted;
6. the relationship of the technique to methods which have been established to be reliable;
7. the qualifications of the expert witness testifying based on ...