Position paper on the derivation of HBM values. Opinion of the German Human Biomonitoring Commission

Human biomonitoring (HBM) is a useful measure for detecting chemical exposures of the general population. HBM assessment values are required for the assessment of potential health risks associated with the presence of chemicals in blood, urine or other biological matrices. Since 1996, the German HBM Commission has derived statistical reference values and several toxicologically founded assessment values (HBM I and HBM II).The assessment values are based on human exposure-response data, and since 2007, according to the extended concept, also on external dose-derived guidance values such as tolerable daily intakes (TDI). The HBM I value represents the concentration of a substance in human biological material below which-according to the knowledge and judgement of the Commission and with regard to the substance under consideration-no risk for adverse health effects and, consequently, no need for action is expected. The HBM II value represents the concentration of a substance in a human biological material above which an increased risk for adverse health effects exists and, consequently, an acute need for exposure-reduction measures and for the provision of medical advice results. The HBM II value should thus be regarded as an intervention or action level. Further development of HBM values by the German HBM Commission follows the concept of a toxicological point of departure (POD) and use of assessment factors (AFs) based on ECHA recommendations, conceptually similar to biomonitoring equivalents (BE). The development of the three different procedures is described. The latter approach broadens the range of chemicals for which assessment values can be derived.