Modelled effect on mesothelioma mortality of the asbestos ban in Italy and the subsequent phases of exposure

BACKGROUND: In Italy, the 1992 asbestos ban prohibited all forms of asbestos production, use and importation. The epidemiological surveillance of mesothelioma mortality and incidence enabled the assessment of the ban's impact and subsequent phases in asbestos exposure patterns. METHODS: To estimate the effects of the ban, a quasi-Poisson generalised linear model was used to fit past asbestos consumption with mesothelioma mortality by gender, using distributed lag non-linear models and different asbestos consumption scenarios with and without ban. Mesothelioma cases in the period 1993-2021 were categorised based on type of asbestos exposure and economic sector of activities involved, to examine their temporal trend and geographical distributions. RESULTS: The avoided number of mesothelioma deaths was estimated to be between 8341 and 21 981 in the period 1992-2020, depending on asbestos use scenario. As for incidence, 37 003 cases were collected between 1993 and 2021. The causal role of direct asbestos use (mining and milling ore and processing asbestos in asbestos-cement and asbestos-textile industry) changed from 11.3% for cases between 1993 and 1996 to 3.2% in the most recent cases (2017-2021). Inversely, cases due to unexpected or atypical exposure to asbestos and in construction increased from 11.3% in 1993-1996 to 17.0% in 2017-2021, and from 12.9% to 21.4%, respectively. CONCLUSIONS: The asbestos ban in Italy has produced substantial health benefits, with many deaths avoided. Countries that still use asbestos should consider evidence of the effects of asbestos bans, as well as the relationship between trends in mesothelioma cases and changing patterns of asbestos exposure.