The European Food and Safety Authority has developed a guide and a software tool called the Persistence in Soil Analytical Model (PERSAM) to carry out exposure assessments in soil.
Until now, the PERSAM program “has helped to calculate the concentration that could be anticipated of a given application of plant protection products”, explained the UPV/EHU lecturer Manu Soto. “We have now managed to extrapolate the potential risks of these concentrations and the factors influencing that risk, not only taking soil conditions into consideration, but also the type of crop and the type of pesticide used.”
Distribution maps of the concentrations observed in soil and in soil pore water (at a depth of 1 cm) after applying the plant protection product esfenvalerate. There are differences in the concentrations between the two types of compartment (a vs b), as well as differences in concentration between different regions, although the application of the plant protection product in Europe has been similar. - Image: UPV/EHU
Erik Urionabarrenetxea, a UPV/EHU researcher: “If toxicity varies depending on soil characteristics, the logic of applying a single dose across Europe cannot be followed, as one dose may have no effect in Sweden, but may exert an effect in Spain or France, for example. The EFSA wanted to make this differentiation, and contacted our group because it was essential to develop a landscape-based assessment method that would take regional variability into account.”