Exposure and Risk Assessment

In this work package we want to create a better understanding of PFAS contamination in and transfer through the aquatic and terrestrial food chains in the Willebroek study area. Also the effect of vertical transfer and ageing of PFAS contamination on plant uptake will be investigated. Based on measured PFAS concentrations, both ecological and human health risks through exposure and consumption can eventually be estimated. 

The PFAS contamination in aquatic and terrestrial food chains will be considered at four locations in the three subsites “former industrial site” , “Fabrieksloop” and “Broek de Naeyer”,  of the study area. For uptake into plants/crops, soil will be collected specifically in “Fabrieksloop and surroundings”. Exposure experiments for vertical transfer to plants will take place at KULeuven. 

For both the aquatic and terrestrial route, known food chain structures will be taken into account. For the aquatic environment, the following matrices will be considered: water/sediment - plants and phytoplankton - macroinvertebrates - bivalves (freshwater mussels) - small fish (e.g. roach, rudd) - large fish (e.g. perch, eel) - cormorant (eggs) - otter (spraints). The terrestrial food chain contains following matrices: soil - plants - worms - isopods - snails - caterpillars/spiders - small mammals (rodents) - songbirds. A total of 42 PFAS components will be analyzed.

Taking into account the age of contamination and the heterogeneity of the soil, the effect of vertical transfer into soil and uptake of PFAS by vegetables and wild plants will be predicted using a model. 

In the study area, high concentrations of other pollutants are known to be present (metals, PAHs, PCBs and organic pesticides). These will also be analyzed in our study in a limited subset of samples. 

• a better understanding on the composition, uptake, accumulation and transfer of PFAS in water, sediment, soil and biota 
• bioconcentration factors (BCFs) for local plants and allotments  
• bioconcentration factors (BCFs), biomagnification factors (BMFs) and trophic magnification factors (TMFs) throughout the aquatic and terrestrial food chain 
• an assessment of the ecological and human health risks of PFAS concentrations in biota