DNA damage and genomic instability among workers formerly and currently exposed to asbestos

Objectives Despite an asbestos ban in the European Union, exposure to asbestos still represents an occupational risk. Biomarkers of DNA damage and genomic instability in groups exposed to asbestos may contribute to the identification of subgroups/subjects at higher risk. Methods A cross-sectional study was conducted on 468 male individuals (80 working in occupational settings with potential exposure to asbestos fibers, 202 retired workers with past exposure, and 186 non-exposed controls) to compare genomic instability, cell proliferation and differentiation level using the non-invasive micronucleus buccal cytome assay. Data on demographic variables, lifestyle, and occupational history were collected with a standardized questionnaire. Micronuclei (MN) and other biomarkers of DNA damage and genomic instability were scored in a minimum of 2000/1000 cells per individual, respectively. Results Univariate and multivariate analysis showed opposite associations of MN frequency with current and former exposure. Compared to unexposed controls, workers with current potential exposure to asbestos had 55% lower MN frequency [95% confidence interval (CI) 71–29%, P