ISP Technologies, Inc. (ISP) appeals the judgment entered by the district court 2 on a jury verdict against it for damages sustained by Katie Bonner. We affirm.
I.
Taking the facts in the light most favorable to the verdict, Katie Bonner was twice exposed to FoamFlush, an organic solvent manufactured by ISP, during her employment on an assembly line in a urethane filter production plant. In March of 1995, the solvent partially dissolved a neoprene hose near Bonner’s work station and sprayed over her in a dense mist. In July of 1995, FoamFlush vapors were released from a drum near her work station. Fo-amflush was used in the plant to clean urethane byproducts from manufacturing equipment. The product was marketed as a “drop-in” replacement for methylene chloride, a carcinogenic solvent, that could be used with systems designed for methylene chloride. FoamFlush contains 57% gamma-butyrolactone (BLO) and three other chemical compounds in smaller quantities. In the human body, BLO metabolizes into gamma-hydroxybutric acid (GHB). Bonner’s work station was poorly ventilated at the time of the first exposure, and her protective gear was limited to gloves and goggles.
*928 Bonner alleged three distinct permanent injuries: (1) psychological problems resulting from both her initial exposure and her health problems, (2) cognitive impairment and personality disorders caused by damage to her brain, and (3) Parkinsonian symptoms caused by damage to her brain. At trial, Bonner presented expert witness testimony tending to show that her exposure to FoamFlush caused all three injuries. The case was tried twice in the district court, and Bonner prevailed both times. After the first trial, the district court granted ISP’s motion for a new trial because one of Bonner’s experts had given testimony that went beyond the scope of his deposition. This appeal is from the second jury verdict, which awarded Bonner $2.2 million for her personal injuries.
II.
ISP argues that the court should have excluded expert witness testimony, that Bonner’s evidence was insufficient to support the jury verdict, that the court improperly refused to give two of ISP’s proposed jury instructions, and that the court' should have granted ISP’s motion for a new trial because of the excessiveness of the verdict.
ISP contends that the district court erred in admitting testimony of Dr. Terry Martinez, a pharmacologist and toxicologist, and of Dr. Raymond Singer, a neu-ropsychologist and neurotoxicologist. It further contends that, because Bonner could not show causation without their testimony, it is entitled to judgment as a matter of law.
To prove causation in a toxic tort case, a plaintiff must show both that the alleged toxin is capable of causing injuries like that suffered by the plaintiff in human beings subjected to the same level of exposure as the plaintiff, and that the toxin was the cause of the plaintiffs injury.
See Wright v. Willamette Indus., Inc.,
“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.” Fed.R.Evid. 702. We review under an abuse of discretion standard a district court’s ruling admitting expert witness testimony under Rule 702.
General Electric Co. v. Joiner,
There is no requirement “that a medical expert must always cite published studies on general causation in order to reliably conclude that a particular object caused a particular illness.”
Heller v. Shaw Indus.,
Although the district court’s gatekeeping function includes an analysis of the reliability of scientific evidence, neither Rule 702 nor
Daubert
requires that an expert opinion resolve an ultimate issue of fact to a scientific absolute in order to be admissible.
Compare Tuner,
As a general rule, the factual basis of an expert opinion goes to the credibility of the testimony, not the admissibility, and it is up to the opposing party to examine the factual basis for the opinion in cross-examination. Only if the expert’s opinion is so fundamentally unsupported that *930 it can offer no assistance to the jury must such testimony be excluded.
Hose v. Chicago Northwestern Transp. Co.,
In a pre-trial motion, ISP sought to preclude the admission of Dr. Martinez’s opinion that Bonner suffered from permanent and progressive Parkinsonian-type tremors because her exposure to Foam-Flush damaged the dopaminergic receptors in her brain, as well as Dr. Singer’s opinion that Bonner suffers from permanent organic brain dysfunction consistent with exposure to FoamFlush. The district court precluded Dr. Martinez from testifying that Bonner’s permanent Parkinsonian symptoms were caused by FoamFlush exposure, but permitted him to testify that Bonner’s acute symptoms were caused by FoamFlush. Dr. Singer was permitted to testify that Bonner suffers from organic brain dysfunction and personality disorders consistent with exposure to a toxic level of FoamFlush.
Dr. Martinez
Dr. Martinez testified at trial that the symptoms Bonner suffered immediately after her exposure to FoamFlush (nausea, headache, tiredness, respiratory problems, trembling, and skin irritation) were caused by that exposure. Dr. Martinez based his testimony on (1) the temporal connection between Bonner’s exposure and acute symptoms; (2) animal studies of the effects of BLO; (3) studies of chemicals with similar structures; (4) his study of the mechanism of GHB and the way it acts on nerve pathways; and (5) Bonner’s medical records. ISP contends that the testimony should have been excluded as irrelevant because of Bonner’s claim of permanent injuries and as prejudicial because the jury may have drawn an impermissible inference that if FoamFlush could cause temporary injuries similar to Bonner’s permanent injuries, it could also be the cause of her permanent injuries. We do not agree, for whether or not such an inference would in fact have been impermissible, Bonner’s acute symptoms were relevant both to Dr. Martinez’s analysis of whether and to what extent she was exposed to BLO and to Dr. Singer’s analysis of her exposure level.
ISP also argues that Dr. Martinez’s opinion should have been excluded as unreliable because there was no epidemiological support for his conclusion that inhalation of FoamFlush could cause the short-term symptoms Bonner described. It argues that the sources Dr. Martinez relied on involve exposure through ingestion, rather than inhalation, of BLO, and do not describe symptoms like those manifested by Bonner after BLO exposure; that Dr. Martinez never determined the quantity of BLO to which Bonner was exposed; and that he failed to rule out other possible causes of her symptoms. In addition, it contends that the fact that Dr. Martinez had designed but not yet tested his theory evidences its unreliability.
As set forth above, our review of the district court’s admission of Martinez’s testimony is for abuse of discretion.
General Electric,
Under some circumstances, a strong temporal connection is powerful evidence of causation.
See Heller,
ISP’s contentions notwithstanding, it was not necessary that Bonner’s experts quantify the amount of FoamFlush to which she was exposed in order to demonstrate that she was exposed to a toxic level of BLO.
See Wright,
Dr. Singer
ISP argues that the district court abused its discretion when it permitted Dr. Singer to testify that FoamFlush caused Bonner permanent injury. Dr. Singer testified that, as a result of her exposure to FoamFlush, Bonner suffered permanent organic brain dysfunction manifesting itself in Parkinsonian physical symptoms, cognitive impairments, and personality disorders. Dr. Singer stated that he followed normal procedures for evaluating patients who might be suffering from toxic exposure. He testified that ingested doses of GHB, BLO’s metabolite, as small as a quarter of a teaspoon can have toxic effects, and that inhalation is a more potent exposure mechanism than is ingestion.
ISP contends that Dr. Singer’s opinion that FoamFlush could cause injuries like Bonner’s was unreliable, pointing to a number of alleged infirmities. The testimony, it argues, should have been excluded because Dr. Singer’s theory was developed for litigation, was not subjected to peer review, has not appeared in scientific literature, and is not supported by epidemiological studies-. Moreover, ISP con *932 tends, the text relied on by Dr. Singer notes that not all organic solvents have similar toxic effects. Additionally, Dr. Singer was unable to offer a threshold exposure amount for injury to occur, failed to determine how much FoamFlush Bonner was exposed to, failed to rule out other possible causes of her injury, and failed to follow established guidelines for diagnosing brain injury.
Our role is not to determine whether Dr. Singer’s opinion was correct; that was for the jury to decide.
See National Bank of Commerce,
ISP contends on appeal that Dr. Singer was not qualified to offer opinions about the impact of FoamFlush on Bonner because he has no degree in toxicology and has done no formal academic work in toxicology. This argument was not presented to the district court, whose pre-trial order noted that “[t]he credentials of the experts are not questioned.” Accordingly, we decline to consider this argument.
See Hogan v. Apfel,
ISP’s sufficiency of the evidence argument is based on the premise that the expert testimony should have been excluded, and that without it, Bonner did not meet her burden of proof on causation, thus entitling ISP to judgment as a matter of law. Because the district court did not abuse its discretion in admitting the expert witnesses’ testimony, it thus did not err in denying the post-trial motion for judgment as a matter of law.
We have reviewed ISP’s other contentions, and we conclude that the evidence was sufficient to support the verdict and that the district court did not abuse its discretion regarding the proffered jury instructions. ISP’s final contention is that the district court abused its discretion when it denied ISP’s motion for a new trial based on an excessive verdict. A verdict should be set aside as excessive only when it is so , excessive that it shocks the conscience.
Drotzmanns, Inc. v. McGraw-Hill, Inc.,
The judgment is affirmed.
Notes
. The Honorable Charles A. Shaw, United States District Judge for the Eastern District of Missouri.
. We have described the Daubert factors as “(1) whether the expert's methodology has *929 been tested; (2) whether the technique has been subjected to peer review and publication; (3) whether the technique has a known or knowable rate of error; and (4) whether the technique has been generally accepted in the proper scientific community.” Turner, 229 F.3d at 1207-08.
