1. Department of Chemical and Biological Work Environment; National Institute of Occupational Health; Oslo Norway
2. Department of Occupational Medicine and Epidemiology; National Institute of Occupational Health; Oslo Norway
3. Department of Toxicology and Carcinogenesis; Nofer Institute of Occupational Medicine; Lodz Poland
4. Department of Environmental Epidemiology; Nofer Institute of Occupational Medicine; Lodz Poland