Foundation Files Amicus Brief on Behalf of Nobel Laureate and Other Prominent Scientists in California Asbestos Case


The Foundation today filed an amicus brief on behalf of a Nobel Prize winner in Medicine and several other prominent scientists to urge the California Court of Appeal in Ruben v. Honeywell International, Inc. to affirm a trial courts decision to exclude plaintiffs expert testimony that even exposure to a single fiber of asbestos can be a substantial contributing cause of peritoneal mesothelioma.

In this case the plaintiff sued 14 manufacturers and suppliers of asbestos containing products, alleging that he developed peritoneal mesothelioma due to exposure to massive amounts of fertilizer containing highly potent tremolite asbestos during his 30 year career as a landscaper. He also claimed he was exposed to asbestos from construction materials, such as pipes, residential siding, and floor tiles, some of which, he claimed, were manufactured by defendant CertainTeed. He did not claim any occupational exposure to Honeywell products; he did, however, allege he was exposed to asbestos from materials he used to replace brakes on his and friends cars on a few occasions, and that these materials were made by Honeywell’s predecessor, the Bendix Corporation. Plaintiff claimed that his peritoneal mesothelioma was caused by each of these exposures. CertainTeed and Honeywell are the only defendants still in the case.

Before trial the Superior Court granted defendants’ motion to exclude plaintiffs expert testimony on the "every exposure" theory, concluding that (i) the materials submitted by Ruben provided no reasonable basis for that theory under Californias Evidence Code, and (ii) the "every exposure" theory cannot establish causation under California law. The trial court precluded plaintiff from presenting expert testimony on the "every exposure" theory, the theory that every exposure to asbestos above background levels is necessarily a causal factor in the development of mesothelioma.
Amici believe that testimony as to the "every exposure" theory was properly excluded because (i) that theory is not scientifically grounded, and (ii) the theory is insufficient to establish causation under Rutherford v. Owens Illinois, Inc. (1997) 16 Cal.4th 953, 977. Under Rutherford, a plaintiff must show not only that he was exposed to asbestos from the defendant’s product, but also that the exposure was "significant enough" to contribute to his risk of developing disease. Moreover, a proper causation analysis must take into account "the length, frequency, proximity and intensity of exposure" and Rubens proffered expert testimony failed to do so.

Most important, our brief points out, there is no reasonable support for the theory that chrysotile asbestos, the type of asbestos contained in Bendix brake materials, is capable of causing peritoneal mesothelioma. Multiple epidemiological studies have shown no association between peritoneal mesothelioma and chrysotile asbestos, and a United States Environmental Protection Agency expert panel has concluded that For mesothelioma the best estimate of the coefficient (potency) for chrysotile is only 0.0013 times that for amphibole and the possibility that pure chrysotile is non-potent for causing mesothelioma cannot be ruled out by the epidemiology data.

We especially criticize plaintiffs expert testimony for failing to take into account the type of asbestos to which plaintiff was exposed through his use of defendants products and the infrequent and isolated instances when he used those products B resulting in minimal exposure to a substance that has very doubtful cancer-causing potential.

We also argue that, under Californias Evidence Code and pertinent California caselaw, the trial court had the authority and obligation to perform a gatekeeping function to assess the probative value of proffered expert testimony, and it was thus correct for the trial court in this case to exclude testimony that did not meet relevant criteria.

To see the Foundations brief, please click here.