Expositionsabschätzung mittels Modellrechnungen

Human exposure to polycyclic aromatic hydrocarbons (PAH) via daily liquid consumption (primarily through the intake of drinking water) is estimated using model calculations based on the indicator substance benzo(a)pyrene. The additional contribution to oral exposure by a consumption of solid nutrients, and by soil and dust ingestion, are evaluated using typical background conditions in Germany (conurbations of North-Rhine-Westphalia). A series of further scenarios is then applied to examine the influence of elevated PAH concentrations in the daily intake of liquid. The degree of PAH exposure via liquid only equals or exceeds the exposure via the solid fraction of the diet under very specific conditions. The contribution via liquid consumption to a total lifelong exposure of both BAP and PAH caused by dietary intake may be estimated as approximately 4 %. It increases to 56 % under a level equivalent to the Dutch intervention value for groundwater and reaches 90 % under a level equivalent to the WHO guideline for drinking water. Considering occupants who live on PAH contaminated garden allotments with private wells, the highest degree of exposure is caused by vegetables followed by house dust, then liquid diet and finally by soil. Finally, the model approach is used for evaluating the success of potential remedial treatments with respect to exposure reduction. In addition to the application of average values, conservative estimates of exposure in terms of 95 % values are set out in this publication based on sumulation methodologies.