Biomonitoring of tram drivers exposed to airborne platinum, rhodium and palladium

Object: The aim of this study was to evaluate urinary levels of Pt, Rh and Pd in occupationally exposed subjects. Methods: A total of 122 healthy male subjects of Rome (Italy) were studied; 64 were municipal tram drivers and 58 control subjects. Metal quantification in the urine samples was carried out by sector field inductively coupled plasma mass spectrometry. Results: There were statistically significant differences between urinary Pt and Rh levels of the workers and the control group (Pt median: 1.23 versus 1.03 ng/g creatinine; Rh median: 19.16 versus 11.18 ng/g creatinine), while no difference in Pd levels was observed (Pd median: 11.47 versus 8.75 ng/g creatinine). Conclusions: Urinary Pt and Rh could be useful biomarkers for monitoring population groups occupationally exposed to these elements. Urinary concentration of Pt and Rh, though still low, could be of some concern in workers heavily exposed to urban car traffic.