pH, ionic strength and dissolved organic matter alter aggregation of fullerene C60 nanoparticles suspensions in wastewater

► nC60 aggregation was tested in wastewater at different pH and ionic strength. ► nC60 remained stable in wastewater under environmentally relevant conditions. ► nC60 size increased greatly at pH 3 or at high ionic strength (>100 mM NaCl). ► nC60 aggregation behavior varied among wastewater samples. ► Inhibition effect indicates steric stabilization due to dissolved organic matter.