Exposure of the German general population to platinum and rhodium − Urinary levels and determining factors

In this study the exposure of the general population in Germany to platinum and rhodium and its determinants was investigated in 259 participants (subdivided in three groups) by urine analyses and assessment of the dental status. Complementary, an interview including questions characterising possible exposure to traffic exhaust was conducted. The median excretion was 2.42 ng platinum/g creatinine and 7.27 ng rhodium/g creatinine. The detailed analysis of the collected data showed significant higher platinum excretion values with increasing number of surfaces covered with restorations containing precious metals (R = 0.389; p < 0.001), but also higher values for habitants of urban areas (median = 3.43 ng/g creatinine; 95th percentile = 25.2 ng/g) compared with those of rural areas (median = 2.06 ng/g creatinine; 95th percentile = 20.0 ng/g). Also, participants working in urban areas showed higher platinum excretion values (median = 3.27 ng/g; 95th percentile = 19.6 ng/g). Male participants living and working next to highly frequented roads showed higher rhodium excretion values (median = 7.27 ng/g; 95th percentile = 13.5 ng/g). In summary, the study showed that exhaust emissions have an influence on platinum and rhodium excretion, but for platinum this influence is rather low compared to the influence of precious metals containing restorations.