Mortality from chronic obstructive pulmonary disease and pleural mesothelioma in an area contaminated by natural fiber (fluoro-edenite)

Objectives. The purpose of the present study was to investigate the association between mortality from chronic obstructive pulmonary disease (COPD) and exposure to fluoro-edenite, a newly discovered amphibolic fiber found in Biancavilla (Sicily), a municipality on the slope of the Etna volcano, where a high mortality from malignant mesothelioma had been previously observed. Methods. Thirty-six municipalities located in the volcanic area of mount Etna were selected for study. An ecological regression model was applied with mortality from COPD as the dependent variable, mortality from mesothelioma as a proxy for exposure to fluoro-edenite, and lung cancer mortality, an urban-rural index, a deprivation index and an aging index as the predictors of COPD mortality. For each municipality, risk classes were determined for the continuous variables with the use of a finite mixture model. Results. A significant association was found between COPD mortality and pleural neoplasm mortality among the women in this study. The association was less consistent for the men. Conclusion. Despite the limitations of this ecological study, the results cohere with the results of toxicologic and observational studies and suggest an etiologic role for fluoro-edenite in nonmalignant respiratory diseases.