1 Institute for Occupational Medicine, Social Medicine and Environment Medicine, Goethe-University Frankfurt, Theodor-Stern-Kai 7, House 9b, 60590, Frankfurt am Main, Germany.
2 Institute for Occupational Health and Safety (IFA) of the German Social Accident Insurance (DGUV), Sankt Augustin, Germany.
3 Institute for Occupational Medicine, Social Medicine and Environment Medicine, Goethe-University Frankfurt, Theodor-Stern-Kai 7, House 9b, 60590, Frankfurt am Main, Germany. holzgreve@med.uni-frankfurt.de.
4 Institute for Occupational Medicine and Maritime Medicine (ZfAM), University Medical Center Hamburg-Eppendorf (UKE), Seewartenstraße 10, House 1, 20459, Hamburg, Germany.