Appellate Law, Product Liability, Publications, Toxic Tort

Has McKinney Changed the Face of Proof of Proximate Causation in Asbestos Litigation in Illinois?

December 12, 2018

The case of McKinney v. Hobart, 2018 IL App (4th) 170333, may be again changing the landscape of proximate causation proof in asbestos exposure disputes in Illinois.

Recent Key Rulings

In Thacker v. UNR Industries, the Supreme Court of Illinois established, “[t]o show causation in an asbestos case, a plaintiff must produce evidence of exposure to a specific product on a regular basis over some extended period of time in proximity to where the plaintiff actually worked.” Thacker v. UNR Industries, 151 Ill. 2d 343 (1992); see also Donaldson v. Central Illinois Public Service Co., 199 Ill. 2d 63, 91 (2002). Under this analysis, the plaintiff in an asbestos case must prove that: (1) the plaintiff worked regularly in an area where the Defendant’s product was frequently used and (2) the plaintiff regularly came into contact with the defendant’s product while in this area. Thacker, 151 Ill. 2d at 354. Thacker and cases from that era involved the use of friable amphibole asbestos insulation or raw materials which generated very high intensity exposures, which if breathed regularly, frequently and from a close proximate source were widely accepted to be sufficient to cause the disease.

Seventeen years later, in a case involving low dose asbestos fiber exposure from boiler sealants, the Supreme Court of Illinois rejected the simplistic application of the frequency, regularity, proximity test as creating a presumption of causation. Nolan v. Weil-McLain, 233 Ill. 2d 416, 430-35 (2009). The Nolan court explained that meeting the frequency, regularity and proximity test is not enough, standing alone, to establish legal causation. While a mechanic changing gaskets on boilers might meet the frequency, regularity, and proximity test, the exposure created during all of that work might remain insubstantial if the exposure amount remains trivial such that the totality of those exposures might leave him well short of what could be deemed a material element and substantial factor. This would be particularly evident if the plaintiff had high intensity exposures to friable asbestos products during other work (e.g., work in a Johns Manville asbestos plant involving raw amphibole asbestos).


In other words, the finality of an adverse jury verdict in low dose asbestos exposure cases is now in serious doubt in light of the analysis and judgment notwithstanding the verdict outcome in McKinney.


In McKinney v. Hobart, 2018 IL App (4th) 170333, the Fourth District Appellate Court recently reversed a $4.6 million McLean County jury verdict against defendant Hobart Brothers Company. In doing so, the Appellate Court clarified requirements for proof of proximate causation in asbestos cases.1

The specific products at issue were welding rods, which the plaintiff alleged gave off asbestos fibers during the welding process. The Appellate Court ruled that the mere presence of a defendant’s product at plaintiff’s workplace was insufficient evidence that the defendant’s product was a substantial cause of plaintiff’s mesothelioma. The Court found no evidence in the record that the alleged exposure to asbestos fibers from welding rods was a material element and substantial factor in bringing about plaintiff’s mesothelioma. Id. ¶83.

“Proving merely that plaintiff came into frequent, close, and regular contact with welding rods manufactured by defendant would not, on the logic of Thacker, prove substantial causation any more than proving he routinely walked on floor tiles containing asbestos would prove substantial causation.” Id. ¶77. Rather, to meet his burden of production, the plaintiff “must prove he actually inhaled respirable fibers from defendant’s welding rods—and that he inhaled enough of the fibers that one could meaningfully say the welding rods were a ‘substantial factor’ in causing his mesothelioma.” Id. ¶78 (emphasis added).

The Appellate Court found that the plaintiff may have breathed some asbestos fibers related to the defendant’s welding rods.  That was not enough.

“[P]laintiff never presented evidence that, but for the asbestos he breathed during his eight-month employment at Portable Elevator, he would not have contracted mesothelioma from the 40 years he spent as a car mechanic working on asbestos-containing brake lines. He never presented any evidence that the asbestos he breathed at Portable Elevator was more than minimal….For all that appears in the record, the amount of asbestos fibers released from defendant’s welding rods by rubbing them together or stepping on them was no more than the amount one would have encountered in a natural environment. Without any idea of the concentration of airborne asbestos fibers the welding rods would have produced, it would be conjectural to say the welding rods were a substantial factor in causing plaintiff’s mesothelioma.” Id. ¶83. 2

In Low Dose Cases, What Quantifies "Enough" Exposure?

What becomes apparent in the evolution of the causation analysis in asbestos exposure cases in Illinois over the last three decades is that the frequency, regularity, proximity test was a measure appropriate when raw or easily fiberized products were being handled, as was the situation in Thacker. But, the analysis changes when the claim is that products such as welding rods in McKinney or other low dose products, such as gaskets and packing in many other cases. This distinction is very important to any case in which the product at issue contained only asbestos encapsulated in binding material which released at most only a very low fiber count, typically measured at 0.04 f/cc or lower, compared to levels of 18-1,000 f/cc in work with friable asbestos products. In particular, McKinney suggests that evidence that the risk of inhalation of asbestos fibers from a product would be insufficient proof of causation. The evidence must show actual inhalation of asbestos fibers from the particular product in question. Furthermore, even if there is sufficient proof of actual inhalation of asbestos fibers from the particular production in question, there must also be evidence that “enough” fibers were inhaled to be a substantial factor in causing disease. McKinney suggests that if a plaintiff can quantify his exposures to defendant’s product and to other products, and the numbers quantified are sufficiently high to raise a question of fact, only then will the jury have some basis to decide whether exposure to a defendant’s product was substantial.

In McKinney, the plaintiff offered the testimony of Dr. Arthur Frank, an expert in occupational medicine, in attempting to prove that the defendant’s product was a material element and substantial factor in causing the disease. It was Dr. Frank’s opinion that all asbestos fibers released from any defendant’s products which are identified by plaintiff combine to create the lifetime fiber dose that caused the plaintiff’s disease. Thus, Dr. Frank opined that each product exposure constitutes a substantial factor in causing the disease. The McKinney court found that because Dr. Frank could not quantify any of the exposures to the defendant’s products, his testimony left the jury with nothing but conjecture about asbestos exposure related to the welding rods. Id. at §83. The plaintiff was required to quantify the exposure created during use of and exposure to asbestos in the defendant’s product because, without some quantification of the exposure, it would be conjecture to say that welding rods were a substantial factor in causing the plaintiff’s disease. Dr. Frank was not able to do so. Id. at §86

In fact, the Court cited Krywin v. Chicago Transit Authority, 238 Ill. 2d 215, 226 (2010), for the proposition that, “Conduct is a material element and a substantial factor if, absent the conduct, the injury would not have occurred.” In other cases, such as Thacker, courts have suggested that the “but for” test and “substantial factor” test are alternative tests, either of which may be used to prove causation. However, the McKinney court appears to be on solid footing in its analysis of the testimony of Dr. Frank and the need to provide some level of quantification of exposures for the jury to decide what exposures might be material and substantial and which are trivial or background level.

It is an open question of what quantifies “enough” fibers to show proximate cause. From McKinney, again, “some” fibers may not be “enough” for purposes of proximate causation. Certainly, the amount of actual fibers inhaled must be above natural environment background levels.

Then, in addition, if there is alternate exposure to asbestos fibers, the duration of the inhalation of fibers from the product in question is of paramount importance. In McKinney, inhalation of some fibers over an eight month period did not qualify as a substantial factor in the development of the plaintiff’s mesothelioma where the alternate exposure duration spanned 40 years.

But, what is the line of demarcation? When do the scales of justice tilt in favor of a finding of substantial factor? What if the alternate exposure was for 10 years, but was to raw asbestos fibers and the exposure to a defendant’s asbestos containing product was for five years but actual inhalation of asbestos fibers from the defendant’s product was minimal? What is “enough”?

Ultimately, proximate causation will likely remain a factual question subject to the deliberations of a jury. However, even if the jury finds that proximate causation is proven, it is clear the Appellate Court will closely examine the factual evidence. And, if there is only evidence of some exposure to a defendant’s asbestos-containing product, that exposure may not be enough to support a jury’s verdict against the defendant manufacturer. In other words, the finality of an adverse jury verdict in low dose asbestos exposure cases is now in serious doubt in light of the analysis and judgment notwithstanding the verdict outcome in McKinney.

1 Plaintiff has filed a Petition for Leave to Appeal to the Illinois Supreme Court, upon which the Court has not yet ruled.

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