Asbestos Product Liability – Mesothelioma Causation


Atlantic Legal Foundation recently submitted an ‘amicus letter’ to the California Supreme Court on behalf of 14 prominent scientists urging the court to grant review in Behshid v. Bondex International, a case involving liability of a manufacturer of plasterboard joint compound for the mesothelioma of an individual whose exposure was limited to his use of joint compound from a variety of manufacturers on a part-time basis for a limited period of time. The defendant’s joint compound contained only chrysotile asbestos, which has been found to be much less potent for causing mesothelioma than other types of asbestos. Plaintiff did not introduce any evidence as to the quantity of asbestos to which he was exposed or to establish the reasonable medical probability that his exposure to this defendant’s product was a ‘substantial factor’ in bringing about the injury, as required by the leading California case on proof in product liability cases.

The issue is whether a plaintiff who has been exposed to multiple sources of asbestos can recover damages from a manufacturer of an asbestos- containing product if the plaintiff shows some exposure to that product, but does not quantify, even approximately, the amount of the exposure.

In the landmark case Rutherford v. Owens-Illinois, Inc. (1997), 16 Cal.4th 953, the California Supreme Court articulated the test for determining whether a plaintiff presented sufficient evidence to show that his exposure to a defendant’s asbestos-containing product was a legal cause of his asbestos-related disease: the plaintiff must establish there is a reasonable medical probability based upon competent expert testimony that exposure to the defendant’s product was a substantial factor in contributing to his risk of developing the asbestos-related disease. Rutherford suggested that the plaintiff must show some amount of exposure to asbestos from the defendant’s product, and that the exposure must exceed a threshold level scientifically proven to increase the risk of developing the disease and that a plaintiff’s exposure to asbestos from the defendant’s product must be ‘significant[] enough’ that an expert could testify it increased the risk of disease to a reasonable medical probability and that a plaintiff typically must show ‘the length, frequency, proximity and intensity of exposure.’

In this case, the Court of Appeal was unconcerned about the absence of any evidence concerning plaintiff’s exposure to Bondex’s product alone. In affirming the almost $3 million judgment against Bondex, it noted that plaintiff’s expert testified the exposure was a significant contributing factor to the development of plaintiff’s disease (even though the expert did not know the amount of exposure) and that nothing more was needed. According to the Court of Appeal: ‘California does not require a specific link to a specific product demonstrating that a plaintiff used that product for a specific period of time. While the evidence with regard to the frequency of exposure, regularity of exposure, and proximity of asbestos coming directly from the use of Bondex was relevant, it was not mandated.’

The Court of Appeal’s decision in Behshid is part of a disturbing trend of recent appellate cases in which California appellate courts have interpreted Rutherford to require nothing more than mere exposure to a defendants’ asbestos-containing product, so long as the plaintiff can find an expert to testify that the exposure is a ‘substantial’ contributing factor.

The Foundation’s amicus letter urges the California Supreme Court to grant review and definitively interpret Rutherford. We argue that Rutherford, properly construed, is consistent with a proper scientific approach to the issue of causation, and that the recent intermediate appellate court decisions diluting the required type and quantum of evidence described in Rutherford as necessary to prove causation is inconsistent with the approach to establishing causation scientists accept.