Special issue on fate and transport of biocolloids and nanoparticles in soil and groundwater systemsSpecial issue on fate and transport of biocolloids and nanoparticles in soil and groundwater systems Εισαγωγή Επιμελητή Editorial 2022-04-202015enHuman activities release an increasing amount of biocolloids and nanoparticles into the environment. While some of the release is accidental or unintentional, sometimes the release of nanoparticles is intentional for the purpose of site remediation or other technical issues. However, the fate and transport of such particles in subsurface systems is not well understood. This special issue is the outcome of a series of symposia on fate and transport of biocolloids and nanoparticles in the subsurface organized by the guest editors at the Annual Meeting of the European Geosciences Union in Vienna, Austria.http://creativecommons.org/licenses/by/4.0/Journal of Contaminant Hydrology1811–2 Chrysikopoulos Constantinos Χρυσικοπουλος Κωνσταντινος Baumann Thomas Flury Markus Elsevier Colloids Nanoparticles Soil pollutants Water pollutants