The “any exposure” theory goes like this:

• Every exposure to a single fiber of asbestos could cause mesothelioma;
• Therefore, a plaintiff only needs to prove one fiber of asbestos from a defendant was inhaled by the plaintiff to prove the defendant caused the plaintiff’s mesothelioma.

On July 11, 2014, the Supreme Court of Texas rejected the “any exposure” theory of causation in mesothelioma cases. See Bostic v. Georgia-Pacific Corp., No. 10-0775, 2014 WL 3797159, *2-5 (Tex. July 11, 2014).

In Bostic, the deceased died of mesothelioma. His estate sued Georgia-Pacific and thirty-nine other defendants alleging they caused Mr. Bostic’s mesothelioma by exposing him to asbestos in the workplace and elsewhere over decades.

Plaintiffs alleged that as a child and teenager, Mr. Bostic was exposed to asbestos while using Georgia-Pacific drywall joint compound. All defendants except Georgia-Pacific settled before trial. The jury found that plaintiffs proved causation against Georgia-Pacific and awarded $6.8 million in compensatory damages and $4.8 million in punitive damages.

Georgia-Pacific argued on appeal that Plaintiffs’ evidence of causation against it was legally insufficient. The Texas Supreme Court agreed:

• It ruled a plaintiff in a mesothelioma case loses if he only proves a defendant caused him “some exposure” or “any exposure”:

“With both asbestosis and mesothelioma, the likelihood of contracting the disease increases with the dose . . . and in today’s case, plaintiffs’ experts consistently testified that all asbestos-related diseases are dose-related.” Id. at *2.

• The court rejected the “any exposure” theory based upon its reasoning that:

“If any exposure at all were sufficient to cause mesothelioma, everyone would suffer from it or at least be at risk of contracting the disease . . .” Id. at *3.

“More fundamentally, if we were to adopt a less demanding standard for mesothelioma cases and accept that any exposure to asbestos is sufficient to establish liability, the result essentially would not be just strict liability but absolute liability against any company whose asbestos-containing products crossed paths with the plaintiff throughout his entire lifetime.” Id.

“We fail to see how the [any exposure] theory can, as a matter of logic, exclude the higher than normal background levels [of asbestos] as the cause of plaintiffs’ disease, but accept that any exposure from an individual defendant, no matter how small, should be accepted as a cause in fact of the disease.” Id. at *5.

• The Texas Supreme Court declined to require that plaintiffs prove “but for causation,” i.e., but for Bostic’s exposure to Georgia-Pacific’s drywall compound in his youth, he would not have contracted mesothelioma. The court explained that due to the nature of mesothelioma’s disease process, which can occur over decades and involve multiple sources of exposure, “but for” causation was too high a burden of proof for plaintiffs exposed to asbestos to carry. Id. at *5-*6.
• Relying on toxic tort cases, the Bostic court concluded that “. . . [in] the absence of direct proof of causation, establishing causation in fact against the defendant in an asbestos-related disease case, requires scientifically reliable proof that the plaintiff’s exposure to the defendant’s product more than doubled his risk of contracting the disease. A more than doubling of the risk must be shown through reliable expert testimony that is based on epidemiological studies or similarly reliable scientific testimony.” Id. at *11

The Bostic case “raises the bar” that plaintiffs must clear to prove causation for mesothelioma cases in Texas. The decision also provides powerful persuasive authority for courts in other states wrestling with the “any exposure” or “every exposure” theory of causation in mesothelioma cases and the sufficiency of scientific evidence necessary to prove causation in asbestosis and mesothelioma cases.

Note: A Louisiana federal court interpreting Louisiana law rejected the “every exposure” theory in interpreting Louisiana law in Davidson v. Georgia Pacific, LLC, No. 12-1463, 2014 WL 3510268, at *3-6 (W.D.La. July 14, 2014).