Assessment of the Long-Term Exposure to Lead in Four European Countries Using PBPK Modeling

Abstract

AbstractLead (Pb) is a naturally occurring heavy metal that received, in the last decades, much attention in the human health risk assessment community. In the European Human Biomonitoring Initiative (HBM4EU), Pb was identified as a priority substance as various scientific and policy questions were open and still to be answered. They included the further investigation of the internal exposure to Pb, the factors determining it, and its variations within European populations. The aim of this work was to develop an integrative modeling framework for the assessment of the aggregated long-term exposure to Pb in Belgium, Czech Republic, Germany, and Norway. This framework enabled predicting the concentrations of Pb in human blood (PbB) from estimates of the external exposure. The effect of past and current exposure events was accounted for, as multiple country-specific Pb concentration data in environmental compartments and diet, and estimates of the dietary intake of Pb covering a period from the 1970s until the present times were compiled. This modeling approach allowed, using a two-dimensional Monte Carlo (MC2D) approach, running a population-based simulation and characterizing the inter-individual variability within the simulated populations and the uncertainty on the external exposure estimates. The predicted PbB levels were compared with the results drawn from HBM data. To the best of our knowledge, this holistic modeling approach combines for the first time temporal and country-specific trends in environmental lead concentrations to derive internal exposure, in order to get better insights into the relationship between environmental and human lead exposure, and to characterize individual exposure at different ages. Graphical Abstract