Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL - Italian Workers' Compensation Authority, Monte Porzio Catone, Rome, Italy. Electronic address: d.cavallo@inail.it. Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL - Italian Workers' Compensation Authority, Monte Porzio Catone, Rome, Italy. Consiglio Nazionale delle Ricerche, Dipartimento di Scienze Bio Agroalimentari (CNR-DISBA), Rome, Italy. Consiglio Nazionale delle Ricerche, Istituto per la Bioeconomia (CNR-IBE), Sesto Fiorentino, Firenze, Italy. Consiglio Nazionale delle Ricerche, Istituto per i Sistemi Biologici (CNR-ISB), Montelibretti, Rome, Italy.