1. Department of Prevention, Unit of Occupational Hygiene and Toxicology, Public Health Laboratory, AUSL South-East Tuscany, Strada del Ruffolo, 4, Siena, Italy
2. Department of Prevention, Unit of Hygiene and Health in the Work Place, AUSL South-East Tuscany, Via Serdini, 46, 53041 Abbadia San Salvatore, Siena, Italy
3. Department of Technical Health Professions, Rehabilitation and Prevention, AUSL South-East Tuscany, Via Serdini, 46, 53041 Abbadia San Salvatore, Siena, Italy
4. Department of Medical Biotechnology, University of Siena, Unit of Occupational Medicine AOU Senese, Viale Bracci, 16, 53100 Siena, Italy