Asbestos Burden in Lungs of Subjects Deceased From Mesothelioma Who Lived in Proximity to an Asbestos Factory: A Topographic Post‐Mortem SEM‐EDS Study

Background: Asbestos exposure and its pathological consequences, especially malignant mesothelioma (MM) still represent a major public health problem on a global scale. After the ban of asbestos in most western countries, nonoccupational exposure plays an essential role in MM pathogenesis. However, few studies have quantified asbestos lung burden after environmental exposure. The main objective of this work is to understand if asbestos lung content is different between occupationally and environmentally exposed individuals, and if the distance between the subjects' residences and the source of exposure is significantly associated with the asbestos lung burden. Methods: In this retrospective, observational study we quantified, with analytical scanning electron microscopy, asbestos content in lungs of individuals deceased from MM between 2005 and 2019, who were exposed to asbestos (occupationally and/or environmentally) in Broni, a small town in northern Italy where an important asbestos-cement plant operated until 1993. Results: We analyzed asbestos lung content of 77 subjects. We found that the asbestos lung content in MM patients who lived around the asbestos factory was as high as that seen in occupationally exposed individuals; this holds true in residents up to 10 km radius from the factory. We found no significant associations between the residence duration/distance ratio and asbestos lung burden. Conclusions: This study suggests that heavy asbestos pollution involves not only the area adjacent to the factory, but the entire town of Broni and the surroundings. This is alarming if we consider that most asbestos factories still active in some countries are located close to towns and dwellings.