In agriculture, large quantities of nano- and microplastics end up in the soil through compost, sewage sludge and the use of mulching foils. The plastic particles always carry various pollutants with them. However, they do not transport them into the groundwater, as is often assumed. Environmental geoscientists have now determined that the plastic particles release the pollutants in the upper soil layers: they do not generally contaminate the groundwater, but have a negative effect on soil microbes and crops.