The opinion of the court was delivered by: Murphy, District Judge
This matter currently is before the Court on a motion to exclude evidence brought by Plaintiff Tommy L. Taylor (Doc. 43) and a motion to exclude evidence brought by Defendant Union Pacific Railroad Company ("UP") (Doc. 49). This case is a suit under the Federal Employer's Liability Act, 45 U.S.C. § 51 et seq., and the Locomotive Inspection Act, 49 U.S.C. § 20701 et seq. Taylor claims that on December 28, 2007, he was working as a locomotive engineer for UP, operating Locomotive UP 9315 on a run from Dexter, Missouri, to Dupo, Illinois. Over the course of approximately four hours, according to Taylor, he was exposed to sulfuric acid fumes from a defective, overheating locomotive battery in the cab of UP 9315. As a result of the said exposure, Taylor contends that he suffers from pulmonary disease, specifically, reactive airways dysfunction syndrome ("RADS"), and is permanently and completely disabled. Taylor now seeks to exclude the testimony of Phillip Goad, a toxicologist retained by UP as an expert witness, while UP seeks to exclude the testimony of Jan Klosterman, a life care planner retained by Taylor as an expert witness.
The Court has reviewed carefully the submissions of the parties. Also, on September 13, 2010, the Court conducted a hearing at which both Goad and Klosterman testified and at which the Court was able to examine both witnesses. The Court rules as follows.
In federal court the admissibility of expert testimony in evidence is governed, of course, by the Federal Rules of Evidence, which provide:
If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testify thereto in the form of an opinion or otherwise, if (1) the testimony is based upon sufficient facts or data, (2) the testimony is the product of reliable principles and methods, and (3) the witness has applied the principles and methods reliably to the facts of the case.
Fed. R. Evid. 702. Rule 702 obligates courts to act as gatekeepers with respect to expert testimony concerning scientific, technical, or other specialized knowledge. See Daubert v. Merrell Dow Pharms., Inc., 509 U.S. 579, 589 (1993); United States v. Conn, 297 F.3d 548, 555-56 (7th Cir. 2002). In evaluating the admissibility of evidence under Rule 702, a court must determine whether (1) the proposed witness would testify to valid specialized knowledge and (2) the expert's testimony will assist the trier of fact. See Kumho Tire Co. v. Carmichael, 526 U.S. 137, 151-52 (1999); Ammons v. Aramark Unif. Servs., Inc., 368 F.3d 809, 816 (7th Cir. 2004). The first prong of this test requires the court to determine whether the expert is qualified in the relevant field and whether the methodology underlying the expert's conclusions is reliable. See Daubert, 509 U.S. at 592; Masters v. Hesston Corp., 291 F.3d 985, 991 (7th Cir. 2002). This calls upon the trial court to assess whether the proffered testimony is both relevant and reliable. See Kumho Tire, 526 U.S. at 152; Jenkins v. Bartlett, 487 F.3d 482, 489 (7th Cir. 2007). In assessing an expert's methodology, a court should consider: (1) whether the proffered conclusion lends itself to verification by the scientific method through testing; (2) whether it has been subjected to peer review; (3) whether it has been evaluated in light of the potential rate of error of the scientific technique; and (4) whether it is consistent with the generally accepted method for gathering the relevant scientific evidence. See Cummins v. Lyle Indus., 93 F.3d 362, 368 (7th Cir. 1996) (citing Deimer v. Cincinnati Sub-Zero Prods., Inc., 58 F.3d 341, 344 (7th Cir. 1995)). However, these factors may not always be pertinent in assessing the reliability of expert testimony, for the Daubert inquiry is a flexible one, and an expert's testimony need not satisfy each of the factors to be admissible. See Daubert, 509 U.S. at 592-94; Chapman v. Maytag Corp., 297 F.3d 682, 687 (7th Cir. 2002). With the foregoing standard in mind, the Court turns to consideration of the motions to exclude the testimony of Goad and Klosterman.
2. Testimony of Phillip Goad
As already has been noted, Phillip Goad is a toxicologist who has been retained by UP as an expert witness. Taylor seeks exclusion of evidence pertaining to certain tests that Goad performed in an effort to determine the level of sulfuric acid fumes in the cab of UP 9315 at the time of the incident giving rise to this case. It appears that Goad conducted three different tests: charging batteries of the same make as the batteries with which UP 9315 was equipped to the boiling point to determine what chemicals the boiling batteries would emit; overheating the batteries in the battery compartment of UP 9315, then measuring the emission products from the batteries as they came out of the compartment and into the cab of the engine; and putting a smoke generator on UP 9315, then pushing it down the rails and taking measurements.
Goad's qualifications as a toxicologist are not seriously in dispute, although Taylor does raise the point that Goad has limited experience with locomotive batteries. However, an expert need not have credentials narrowly tailored to the subject matter of a case in order to pass muster under Rule 702, so long as the expert is testifying to matters within the area of his or her expertise. "The notion that Daubert . . . requires particular credentials for an expert witness is radically unsound . . . . Anyone with relevant expertise enabling him to offer responsible opinion testimony helpful to judge or jury may qualify as an expert witness." Tuf Racing Prods., Inc. v. American Suzuki Motor Corp., 223 F.3d 585, 591 (7th Cir. 2000). See also Latham v. Edelbrock Corp., Civil No. 07-713-GPM, 2009 WL 3156554, at *1 (S.D. Ill. Sept. 26, 2009) (citing Stagl v. Delta Air Lines, Inc., 117 F.3d 76, 81-82 (2d Cir. 1997)) ("[A]n expert is not precluded from testifying merely because he or she does not possess experience tailored to the precise product or process that is the subject matter of a case, provided that the expert is testifying within the general area of his or her expertise[.]"); McCloud v. Goodyear Dunlop Tires N. Am., Ltd., 479 F. Supp. 2d 882, 887-90 (C.D. Ill. 2007) (an expert in rubber polymers and tire mechanics could testify in a case pertaining to motorcycle tires although he had limited experience with the manufacture of such tires); Abdishi v. Philip Morris, No. 98 C 1310, 1999 WL 756054, at *9 (N.D. Ill. Sept. 7, 1999) (a toxicologist could testify generally about the toxicity of a substance causing irritation to the skin although he did not have any experience dealing with the toxicity of the substance in humans).
Taylor's remaining objections to Goad's evidence go chiefly to Goad's supposed failure to replicate exactly in his testing the conditions prevailing on UP 9315 at the time of the toxic exposure incident giving rise to this case. For example, Taylor argues that Goad's tests are inaccurate because: the batteries Goad used in the testing did not contain broken internal jumpers; Goad used batteries that were not burned; Goad used batteries that contained electrolyte; Goad did not attempt in his testing to duplicate the temperature, wind speed and direction, and humidity prevailing at the time of the alleged exposure incident; and Goad did not perform his tests aboard a moving locomotive with air inlets. Taylor also challenges Goad's tests as being contrary to eyewitness testimony about the exposure incident because the testing produced neither smoke nor an odor of sulfuric acid fumes. Finally, Taylor appears to suggest that Goad's testimony is motivated by the fact that Goad has a contract with UP whereby he provides services in incidents involving derailment and chemical release. UP has produced detailed rebuttals to each of Taylor's objections to Goad's testing and, in any event, as should be clear from the foregoing discussion, Taylor's objections to Goad's testimony are challenges to Goad's credibility as a witness and the weight to be afforded his testimony. As Daubert teaches, however, "[v]igorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence." 509 U.S. at 596. The decision about whether an expert is "credible or whether his or her theories are correct" is a factual determination for a jury to make "after opposing counsel has been provided the opportunity to cross-examine the expert regarding his conclusions and the facts on which they are based." Smith v. Ford Motor Co., 215 F.3d 713, 719 (7th ...