Fate and occurrence of micro(nano)plastics in soils: Knowledge gaps and possible risks

Summary

The majority of micro(nano)plastic research has been concentrated on the marine environment. Whilst the ocean represents an ultimate sink for contamination, this focus overlooked key processes and pathways of micro(nano)plastics in the terrestrial environment that are of critical importance for their global environmental budget and exposure of humans and biota. Lack of robust analytical methods for the isolation of these materials from complex, organic-rich soil matrices represent a major hindrance. Regardless, soils in agricultural and urban areas are expected to represent major environmental reservoirs of micro(nano)plastics, possibly comprehensively larger than the marine one. Additionally, soils exhibit several potential exposure pathways for micro(nano)plastics to organism and human health, including contamination of groundwater aquifers.