Mass Tort Defense : Mass Tort Defense Lawyer & Attorney : Sean P. Wajert : Dechert Law Firm : Products Liability, Class Actions, Pharmaceutical Litigation

A federal court has excluded plaintiffs' expert testimony in litigation alleging personal injury and property damage from releases at a Midwest refinery.  Baker, et al. v. Chevron USA Inc., et al., No. 05-cv-00227 (S.D. Ohio Jan. 6, 2010). In the absence of necessary expert testimony, the claims were subject to summary judgment.

Plaintiffs in this case were residents of the villages of Hooven and Cleves, Ohio, who asserted claims for personal injury and property damage allegedly resulting from the Gulf Oil refinery, now owned by defendant Chevron USA.  Gulf operated a gasoline refinery which was situated on the eastern edge of Hooven from 1930 to 1985. Gulf also refined diesel fuel, jet fuel, and fuel oil at the refinery and operated an asphalt plant at this location. Gulf and Chevron merged in 1985, and Chevron closed the refinery in 1986.

Plaintiffs alleged that Gulf’s operation of the refinery resulted in the release of millions of gallons of gasoline and diesel fuel.  But these plaintiffs did not claim injuries resulting from groundwater contamination. Rather, they asserted injuries allegedly caused by air emissions from the refinery and, in particular, the benzene contained in those emissions. Benzene is ubiquitous in the ambient air and is a component or constituent of vehicle exhaust and cigarette smoke. In the petroleum industry, benzene is found in small amounts in gasoline.

For case management purposes, the matter was bifurcated between personal injury claimants and property damage claimants. The parties were permitted to select bellwether plaintiffs for each trial group. This opinion dealt with the claims of the bellwether personal injury claimants, and a key issue, as is often the case in toxic tort litigation, was causation.

Regarding their alleged benzene exposure, plaintiffs offered a three-step procedure. First, expert Dr. Cheremisinoff calculated a gross amount of benzene released from the refinery through emissions. Then, using those calculations, Dr. Rosenfeld, plaintiffs’ second expert, used an air flow model to calculate the cumulative dose of benzene to which each plaintiff was exposed. Third, using those dose estimates, a third expert, Dr. Dahlgren, submitted opinions that each plaintiff’s dose of benzene was sufficient to cause her illness. 

Chevron moved to exclude Dr. Dahlgren's opinions under Daubert, and for summary judgment contingent  upon the striking of  plaintiffs' causation evidence. The principal argument raised was that Dr. Dahlgren’s opinions were unreliable because there was an insufficient scientific or medical basis to conclude that the doses of benzene to which plaintiffs’ were exposed were large enough to have caused their illnesses. Relatedly, Chevron contended that there is an insufficient scientific or medical basis to conclude that benzene even causes some of the illnesses alleged. The Court held a hearing on Chevron’s Daubert motion during which Dr. Dahlgren and Chevron’s medical expert also testified.

In a toxic tort case, the plaintiff must present evidence of both general causation and specific causation. General causation establishes whether the substance or chemical at issue is capable of causing a particular injury or condition. Specific causation relates to whether the substance or chemical in fact caused this plaintiff’s medical condition. Without expert medical testimony on both general causation and specific causation, a plaintiff’s toxic tort claim will fail.

In this case, Dr. Dahlgren offered causation opinions based largely on epidemiological studies. (Epidemiology is the study of the incidence, distribution, and etiology of disease in human populations.) Epidemiology is usually considered highly probative evidence on general causation in toxic tort cases. The court may nonetheless exclude expert testimony based on epidemiological studies where the studies are insufficient, whether considered individually or collectively, to support the expert’s causation opinion. Nothing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence that is connected to existing data only by the ipse dixit of the expert. A court may thus conclude that there is simply too great an analytical gap between the data and the opinion proffered.

A couple of parts of the court's detailed analysis are worth highlighting for readers of  MassTortDefense:

First, Dr. Dahlgren’s reliance on the “one-hit” or “no threshold” theory of causation in which exposure to one molecule of a cancer-causing agent has some finite possibility of causing a genetic mutation leading to cancer. The court noted that while the one-hit theory has been accepted for purposes of establishing regulatory safety standards, it has not been accepted as a reliable theory for causation under Daubert standards.  See Allen v. Pennsylvania Eng’g Corp., 102 F.3d 194, 199 (5th Cir. 1996) (“Scientific knowledge of the harmful level of exposure to a chemical, plus knowledge that the plaintiff was exposed to such quantities, are minimal facts necessary to sustain the plaintiffs’ burden in a toxic tort case.”); McClain v. Metabolife Int’l, Inc., 401 F.3d 1233, 1240 (11th Cir. 2005) (holding that district court erred by not excluding plaintiff’s expert’s causation opinion because he neglected dose-response relationship); Henricksen v. ConocoPhillips Co., 605 F. Supp.2d 1142, 1162 (E.D. Wash. 2009) (excluding expert’s opinion pursuant to Daubert where “he presumed that exposure to benzene in gasoline can cause AML in any dose.”); National Bank of Commerce v. Associated Milk Producers, Inc., 22 F. Supp.2d 942, 961 (E.D.Ark. 1998), aff’d, 191 F.3d 858 (8th Cir. 1999); Sutera v. Perrier Group of Am., Inc., 986 F. Supp. 655, 667 (D. Mass.
1997). Moreover, since benzene is ubiquitous, causation under the one-hit theory could not be established because it would be just as likely that ambient benzene was the cause of plaintiffs’ asserted illnesses.

Second, the court noted that to the extent that Dr. Dahlgren relied on the evidence that plaintiffs were exposed to benzene in excess of regulatory levels, that is insufficient to make his opinions admissible. The mere fact that plaintiffs were exposed to benzene emissions in excess of mandated limits is insufficient to establish causation. Nelson v. Tennessee Gas Pipeline Co., 243 F.3d 244, 252-53 (6th Cir. 2001); David L. Eaton, Scientific Judgment and Toxic Torts- A Primer in Toxicology for Judges and Lawyers, 12 J.L. & Pol’y 5, 39 (2003) (“regulatory levels are of substantial value to public health agencies charged with ensuring the protection of the public health, but are of limited value in judging whether a particular exposure was a substantial contributing factor to a particular individual’s disease or illness.”). This is because regulatory agencies are charged with protecting public health and thus reasonably employ a lower threshold of proof in promulgating their regulations than is used in tort cases. Allen, 102 F.3d at 198.

Third, the court focused on the issue of the link between cited literature and the actual specific opinion given. The court recognized that an expert’s opinion does not have to be unequivocally supported by all epidemiological studies in order to be admissible under Daubert. But here, the opinions expressed in Dr. Dahlgren’s revised report were based "on a scattershot of studies and articles which superficially touch on each of the illnesses at issue." The expert had not differentiated the cases in any way and simply assumed that each reference supported his causation opinion on each and every illness. That clearly was not the case. Also, none of the cited studies supported an opinion that benzene can cause the illnesses from which plaintiffs suffer at the extremely low doses or exposures experienced in this case. Even if it is medically accepted that benzene can cause disease at high doses, Dr. Dahlgren could not cite any paper finding that the relevant low cumulative exposure significantly increases the risk of developing the injuries.

The court, therefore, found that the expert's causation opinions were not reliable under the standards enunciated by Daubert and, consequently, inadmissible. Without Dr. Dahlgren's testimony, the plaintiffs were unable to establish that their illnesses were caused by alleged emissions from the plant, the court observed, and so granted Chevron's motion for summary judgment on all four bellwether personal injury plaintiffs.
 

• Email This
• Print
• Comments
• Trackbacks

A federal court has granted summary judgment in a toxic tort suit in which plaintiff alleged he contracted a bone disease because of his long-term exposure to trace amounts of benzene in oil-based paint. Smolowitz v. The Sherwin-Williams Co., 2008 WL 4862981 (E.D.N.Y. Nov. 10, 2008). Plaintiff failed to offer sufficient evidence under New York law of exposure level.

In order to prevail in a toxic tort case, plaintiffs must present sufficient evidence to support a finding that defendants' products caused plaintiffs' injuries. Proof of causation requires establishing both “general” causation and “specific” causation.  General causation bears on whether the type of injury at issue can be caused or exacerbated by the defendant's product. Specific causation bears on whether, in the particular instance, the injury actually was caused or exacerbated by the defendant's product.  The fundamental principle of toxicology is that the dose makes the poison: substances that are benign or even beneficial at a certain level can be toxic at another. Even when general causation is clear, a plaintiff must show that he or she was exposed to a sufficient dose of the substance to have caused the disease. Under New York law, plaintiffs must establish both general and specific causation through expert testimony

Plaintiff Richard Smolowitz worked as a drywall taper and spackler over a thirty year period beginning in the 1950s and ending in the early 1980s. Plaintiff alleges that his exposure to benzene in paints caused him to contract myelodysplastic syndrome (“MDS”).  A central factual issue in this case, said the court, was the level of exposure to which plaintiff was subject, and whether that level of exposure can cause MDS. First, plaintiff was not a painter, but alleged he worked in areas where paint products were regularly used. Second, the solvents used in defendants' oil based paints contained only a trace contamination of benzene due to the fact that the products are based on petroleum, and it is not always possible to remove all of the benzene during the manufacturing process.

In early motion practice, plaintiff's counsel represented that he would provide the testimony of expert witnesses who could prove that plaintiff was exposed to oil based paints with sufficient levels of benzene to cause his illness. Eventually, he relied on the opinions of plaintiff's treating physician, Dr. Silverman, to provide expert testimony on issues of general and specific causation. The doctor reported he was currently treating plaintiff for MDS; that Smolowitz reported a history of exposure to oil based paints, thinners and benzene during a 35-year period; and that in his opinion it was “likely to a reasonable medical probability, that Mr. Smolowitz's exposure to benzene during the years that he worked as a dry-wall mechanic is causative for his current hematologic condition.”

The court concluded that Dr. Silverman's testimony was inadequate to prove either general or specific causation. The conclusory statement that based upon plaintiff's reported history it was likely to a reasonable medical probability that Mr. Smolowitz's exposure to benzene during the years that he worked as a dry-wall mechanic is causative for his current hematologic condition, had substantial deficiencies. First, there was nothing in this statement that suggests that Dr. Silverman was aware of or had quantified the precise amount of benzene to which plaintiff was exposed. No proof of dose. Second, Dr. Silverman did not offer any opinion as to whether that limited level of benzene exposure, whatever it was, can cause the disease. In the absence of sufficient evidence from an expert or a treating physician of the plaintiff's exposure level, plaintiff could not prove the essential causation element of the claim.
 

• Email This
• Print
• Comments
• Trackbacks

The 8th Circuit has upheld the trial court’s decision that a plaintiff who alleged she was injured by drinking water from a bottle filled with freon did not have adequate and valid expert evidence of causation. Bland v. Verizon Wireless, 2008 WL 3474178 (8th Cir. August 14, 2008).

Plaintiff alleged that she inadvertently left her water bottle behind in a store, and an employee of defendant sprayed compressed air into her water bottle “as a joke,” believing the water bottle belonged to a fellow employee. At home, plaintiff opened the bottle which “made a-kind of pressurized noise.” She took a drink, then decided to smell the contents, taking a big whiff which made her cough. She then allegedly took another drink.

Plaintiff later reported to her doctor that after drinking from the bottle she coughed, which persisted for nearly an hour. She also described a “sore sensation in her throat” and for the next few days a “raspy sensation in her lungs.” Plaintiff alleged she developed a headache which persisted for about two weeks. Later testing at the University of Iowa Lab determined the bottle contained 820 parts per million (ppm) (.08%) of difluoroethane, a freon compound.

Plaintiff was later seen by a Dr. Sprince, complaining of shortness of breath when running. Her lung function test results were basically normal. Dr. Sprince eventually diagnosed her as having “exercise-induced asthma.” Dr. Sprince later theorized that “[b]ased on the initial clinical findings, [a] strong temporal relationship between the inhalation of freon and the occurrence of respiratory symptoms, and the subsequent response to pre-exercise treatment with inhaled bronchodilator” that plaintiff's exercise-induced asthma was caused by the inhalation of freon.

Plaintiff sought to use the testimony of this treating physician, Dr. Sprince, to establish a causal link between inhalation of freon and the alleged exercise-induced asthma. The district court excluded Dr. Sprince's testimony because Dr. Sprince's proffered testimony as to causation did not satisfy the standards for admission of expert scientific testimony under Daubert.

The 8th Circuit affirmed, noting first that a treating physician's expert opinion on causation is subject to the same standards of scientific reliability that govern the expert opinions of physicians hired solely for purposes of litigation.

The first problem with Dr. Sprince's causation testimony was that she failed scientifically to eliminate other possible causes as part of her differential diagnosis. In particular, her own testimony acknowledged the cause of exercise-induced asthma in the majority of cases is unknown. Where the cause of the condition is unknown in the majority of cases, an expert cannot properly conclude, based upon a simple differential diagnosis, that exposure, here to freon, was the most probable cause of the injury. As a practical matter, Dr. Sprince's causation opinion could not possibly be based upon a reasonable degree of medical certainty. Where the majority of cases of exercise-induced asthma have no known cause, and where Dr. Sprince failed to do an investigation and analysis of plaintiff's home or other environments in search of other possible causes, the district court did not abuse its discretion in determining Dr. Sprince's differential diagnosis did not satisfy Daubert.

Second, plaintiff’s expert did not know what amount of exposure to freon causes, or involves an appreciable risk of causing, asthma, and had no good grounds for determining whether plaintiff  was exposed to a sufficient dose to have caused her asthma. Dr. Sprince could not determine or estimate the amount of freon plaintiff was actually or probably exposed to. The expert could not extrapolate from the existing data because the gap between the data identified (exposure facts) and Dr. Sprince's proffered opinion was simply too great an analytical gap to support admissibility. Critical to a determination of causation is characterizing exposure. In a toxic tort case, the magnitude or concentration of an exposure should be estimated and the temporal aspects of the exposure should be determined --whether the exposure was short-term and lasted a few minutes, days, weeks, or months, or was long-term and lasted for years. Dr. Sprince lacked knowledge regarding what level of exposure to freon constitutes an appreciable risk of causing asthma and the specific concentration and degree of exposure to the freon. Similarly, plaintiff’s expert did not offer as evidence any personal experience with treating other patients following a similar exposure, admitting she had no such experience.

Finally, the expert’s heavy reliance on temporal proximity, without more, was insufficient to establish causation. In the absence of an established scientific connection between exposure and illness, or compelling circumstances, the temporal connection between exposure to chemicals and an onset of symptoms, standing alone, is entitled to little weight in determining causation. See Moore v. Ashland Chem., Inc., 151 F.3d 269, 278 (5th Cir.1998). It is not always irrelevant, said the court. The temporal relationship often will be one of several factors, and the weight to be given to the temporal relationship will differ depending on the strength of that relationship. But in this case, the district court properly discounted all the other factors supporting Dr. Sprince's opinion leaving only temporal proximity to support Dr. Sprince's causation opinion. And that was not enough, especially when plaintiff did not make an appointment with a doctor until two to three weeks after the incident.
 

• Email This
• Print
• Comments
• Trackbacks