One-Fourth of Peritoneal Mesothlioma Cases Happen via Secondhand Asbestos Exposure

When one reads about an individual who is suffering from mesothelioma, most often it is the pleural form of the disease that afflicts that particular person.

Indeed, malignant pleural mesothelioma is the most common type of asbestos-caused cancer, accounting for about 75 to 80 percent of all cases diagnosed in the U.S. each year.

Pleural mesothelioma affects the lining of the lungs – the pleura – and is the type of mesothelioma on which most research has been focused.

A rarer form of the disease is peritoneal mesothelioma. It affects the lining of the abdomen and accounts for about 10-15 percent of all cases diagnosed in the U.S. annually.

The peritoneal type of mesothelioma is extremely aggressive, usually advanced at time of diagnosis, and has historically been associated with individuals who have suffered hefty exposure to the more toxic amphibole forms of asbestos, known as crocidolite and amosite, although some diagnoses have been linked to the more-common white chrysotile asbestos.

However, the results of a new study, published in the American Journal of Industrial Medicine, demonstrates that while about two-thirds of the 62 individuals who took part in this research developed peritoneal mesothelioma due to prolonged industrial exposure, 23 percent of those individuals had been exposed solely during what the authors are referring to as “take-home exposures.”

This means they were exposed to asbestos via family members who carried toxic dust on their clothes or body from their workplace to their home.

Of the 23 percent who had suffered secondary exposure, 71 percent of those individuals were women who had been responsible for laundering the work clothes of a spouse or other family member who worked daily with the toxic mineral.

In most cases, it took at least 20 years for these “domestic” cases of peritoneal mesothelioma to occur, though often much longer.

The authors, Kradin et al, note that most of the 51 men and 11 women in the study, all diagnosed with diffuse peritoneal mesothelioma, had been exposed to both amphibole and chrysotile asbestos though 26 percent of the test subjects had been exposed to only the chrysotile form of the mineral.

That proves, they add, that not only can one develop peritoneal mesothelioma from secondhand exposure but also – contrary to popular belief – peritoneal mesothelioma can indeed be a result of exposure to chrysotile asbestos only.

“The present study belies the claim that low-level exposures to chrysotile are safe and cannot cause peritoneal mesothelioma,” wrote lead author Richard Kradin. “Furthermore, there is increasing evidence that a variety of products, including cosmetic talcum powders routinely contained asbestos, and may be responsible for so-called idiopathic cases of both pleural and peritoneal mesotheliomas, especially in women.”