Funding for this research was provided by:
Narodowe Centrum Nauki (UMO-2017/27/B/NZ7/01921.)
Received: 7 February 2019
Accepted: 20 February 2020
First Online: 2 March 2020
Ethics approval and consent to participate
: The Nofer Institute of Occupational Medicine Bioethical Committee Board approved the study (resolution no. 23/2014 and for the continuation: resolution no. 10/2018).and written informed consent was obtained from all subjects before their participation.
: Not applicable.
: The authors declare that they have no competing interests.