Text and Data Mining valid from 2019-09-02
Received: 12 March 2019
Accepted: 23 August 2019
First Online: 2 September 2019
Ethics approval and consent to participate
: All participants gave their informed consent. All information regarding participants was rendered anonymous after collection of data, urine and blood samples. The study was reviewed and approved by the appropriate Ethics Committee of the Institute of Occupational Medicine and Environmental Health in Sosnowiec (Poland). Agreement No. 20 published in December 2001.
: Not applicable.
: The authors declare that they have no competing interests.