Malignant Mesothelioma Risk Related to Cumulative Asbestos Exposure: Study

A recent report by an international group of scientists may play an important role in future malignant mesothelioma lawsuits, with findings that appear to refute industry claims that only the earliest asbestos exposures factor into the risk of developing the rare and often deadly form of cancer.

In findings published in the medical journal Industrial Health, researchers with the Collegium Ramazzini indicate that the risk of malignant mesothelioma is related to cumulative asbestos exposure, finding that there is ample evidence that recent and remote exposure to the toxic substance “contribute to the totality of risk.”

The Collegium Ramazzini is an international group of physicians and scientists from 35 countries, which reviewed science dating back to at least 2011 to evaluate the exposure-response relationship between asbestos and mesothelioma.

The researchers indicate that the Epidemiology and Public Health Working Group of the Second Italian Consensus Conference on Pleural Mesothelioma “concluded that there is convincing evidence that mesothelioma incidences is proportional to cumulative asbestos exposure.” Later studies have appeared to confirm these findings, the group said.

“‘Subsequent’ exposures cannot, thus, be considered without influence on mesothelioma risk on the basis of the available evidence, as they necessarily contribute to cumulative exposure,” the group wrote. “In summary, the Collegium Ramazzini concludes that risk of malignant mesothelioma is related to cumulative exposure to asbestos in which all exposures — early as well as late — contribute to the totality of risk.”

Mesothelioma is a rare and often fatal form of cancer, which is only known to be caused by exposure to asbestos fibers, which were used in a variety of manufacturing and building industries until most uses were banned more than 30 years ago. The condition is often not diagnosed until it is already at a very advanced stage, resulting in a very short life-expectancy.

The new report by Collegium Ramazzini notes that cases of malignant mesothelioma continue to increase in most industrialized countries, and is not expected to peak until around 2020, due to the long latency period between exposure to asbestos and diagnosis of mesothelioma.

Asbestos exposure lawsuits have been one of the largest mass-torts in U.S. history, with more than 600,000 people having filed a case against more than 6,000 defendants after being diagnosed with mesothelioma or other related injuries that were allegedly caused by inhaling asbestos fibers. In addition, as more individuals learn they are suffering from the disease, it is likely that additional cases will continue to be filed for decades.

Many companies that manufactured asbestos products or caused individuals to be exposed to the toxic substance without providing adequate safety protections have attempted to defend lawsuits over mesothelioma by maintaining that earlier potential exposures are the cause of the disease. However, the findings of this latest report help refute these claims.

“The Collegium Ramazzini rejects as false, mendacious and scientifically unfounded the claim put forth by the Italian asbestos industry and its expert witnesses that in cases of prolonged exposures to asbestos only the earliest periods of exposure contribute to mesothelioma induction, while all subsequent exposures have no causal link,” concluded the report. “The Collegium Ramazzini is deeply concerned that acceptance of this false claim will contribute to the unjust denial of wokers’ compensation and civil damages to affected workers, that it will hinder efforts to diagnose and prevent malignant mesothelioma, and that it will undermine the health of the public in Italy and in countries around the world.”