German health-related environmental monitoring: assessing time trends of the general population's exposure to heavy metals.

The German system of a health-related environmental monitoring is based upon two instruments: The German Environmental Survey (GerES) and the Environmental Specimen Bank (ESB). The ESB is a tool to describe time trends of human exposure. Each year approx. 500 students from 4 sampling locations are analysed for their heavy metal contents in blood, blood plasma, and urine. GerES is a nationwide representative cross-sectional study that has been conducted four times up to now. Both instruments have been used to measure heavy metals over the last decades and thus provide complementary information. Both instruments are useful to describe time trends. However, combining the two has an added value, which is demonstrated for heavy metals for the first time in this paper. Major results and the changing importance of sources of exposure to heavy metals (Pb, Cd, Hg, Au, Pt, U and Ni) are shown. This leads to the following conclusion about the today's relevance of exposure in Germany. For the study participants of the city of Muenster, lead in whole blood decreased from about 70 μg/l in 1981 to levels below 15 μg/l in 2009. GerES data of young adults confirmed this time trend and GerES IV on children revealed the decreasing relevance of lead in outdoor air and in drinking water. The concentrations of mercury in urine decreased because in Germany it is no longer recommended to use amalgam fillings for children. However, GerES IV and ESB data also demonstrate that despite the decline of these heavy metals exposures to nickel and uranium originating from drinking water are still of importance.