The dispersion, stability, and resuspension of C in environmental water matrices.

Abstract

Environmental waters cover a range of water quality characteristics which could greatly affect the behavior and fate of C60 in the aquatic environment. In this study, the dispersion and stability of C60 in several environmental water matrices during a 70-day extended mixing period were investigated to better understand its environmental behavior and fate in environmental waters. Relatively stable nanoscale aggregates in water (aqu/nC60) could be formed in wastewater influent, while unstable suspensions were obtained in river water, wastewater effluent, seawater, and estuarine water. During the extended mixing under sunlight, oxygen-containing moieties were produced on the surface of the C60 aggregates, independent of the kind of environmental water matrices. Once the mixed system went under quiescent condition, aggregation and sedimentation of aqu/nC60 occurred. However, an extremely short-time disturbance could easily resuspend the C60 aggregates deposited and increase the concentration of aqu/nC60 in the overlying water column. Therefore, the effects of resuspension should be considered when investigating the environmental behavior and fate of C60.