New research out of Italy is further evidence that asbestos – and not other dusty minerals like talc – is almost always the cause of pleural mesothelioma.
The evidence comes from a 50-year study of more than 1,700 Northern Italian talc miners and millers.
Talc and asbestos often lie close together in the ground. Some people who have worked in talc mines or even used talc products have developed malignant mesothelioma. Many of these mines and products were contaminated with asbestos. This makes it difficult to know if it was the talc or the asbestos that caused the cancer.
But the workers in the new study worked in a mine that was uncontaminated with asbestos. Analysis of their causes of death show that talc alone is unlikely to be a cause of pleural mesothelioma.
Asbestos, Talc, and Mesothelioma
Like asbestos, talc is a mineral. It contains magnesium, silicon, oxygen and hydrogen. As a powder, it absorbs moisture. People use it to help keep skin dry and prevent friction rashes. Talc also helps keep powdered products from caking.
The International Agency for Research on Cancer (IARC) does not classify talc as a carcinogen. So what is the cause of pleural mesothelioma in people who have been exposed to talc for a long time? Probably asbestos.
Like talc, asbestos is also a mineral but it has a different crystalline structure. Unlike talc, asbestos is a known carcinogen. It’s structure makes it hard for the body to expel it after inhalation. Asbestos triggers physiological changes that can be the cause of pleural mesothelioma years later.
Last year, researchers in Virginia published a study of cosmetic talc users who developed mesothelioma. None of the patients had any known exposure to asbestos. But microscopic examination of their tissues showed the presence of asbestos fibers.
The newest study adds even more credence to the idea that talc alone does not cause mesothelioma.
Further Evidence That Talc is Not a Cause of Pleural Mesothelioma
There were 1,749 workers in the new Italian study (1,184 miners and 565 millers). These men worked in the talc mine between 1946 and 1995. No asbestos was ever detected in their mine.
University researchers analyzed all the different causes of death among the workers. In all that time, there were no deaths from mesothelioma. The miners did not have a higher risk of lung cancer either. They did have increased mortality from pneumoconiosis, a lung disease caused by exposure to silicon.
The research team says it shows that uncontaminated talc is not a cause of pleural mesothelioma.
“This uniquely long-term follow up confirms the results of previous analyses, namely the lack of association between exposure to talc with no detectable level of asbestos and lung cancer and mesothelioma,” writes Catalina Ciocan, a public health researcher at the University of Turin.
The study does not mean that talc-containing products are safe. It is not possible to detect asbestos in talc without laboratory testing. Asbestos-tainted talc has led to hundreds of lawsuits again manufacturers. Many continue to insist that their products are pure.
Ciocan, C, et al, “Mortality in the cohort of talc miners and millers from Val Chisone, Northern Italy: 74 years of follow-up”, August 11, 2021, Environmental Research, online ahead of print, https://www.sciencedirect.com/science/article/abs/pii/S0013935121011592?via%3Dihub