Bioaccumulation of Zn and Ag Nanoparticles in the Earthworms (Eisenia fetida)

Abstract

With an absence of data that accurately measure ENP concentration in the environment, modeling studies predicted that ENPs released into the environment would be transferred mainly to the soil of the terrestrial environment and the terrestrial environment is a major removal location of introduced ENPs. In the present study radiolabeled nanoparticles were successfully synthesized and were used to trace nanoparticles in the sediment and animals during exposure and depuration periods. ZnO was bioaccumulated in the worms but was much less bioavailable than ionic Zn while bioaccumulation of Ag in the worms were similar regardless of chemical forms of Ag in the soil. Efflux rate of Ag in the worm was 2-3 faster than those of Zn, but there were no significant difference among their chemical forms. Subcellular partitioning of Zn and Ag was similar among their chemical forms. Sequential extraction was not a good predictor or bioavailability of nanoparticles in soil.rial environment is a major removal location of introduced ENPs. In the present study radiolabeled nanoparticles were successfully synthesized and were used to trace nanoparticles in the sediment and animals during exposure and depuration periods. ZnO was bioaccumulated in the worms but was much less bioavailable than ionic Zn while bioaccumulation of Ag in the worms were similar regardless of chemical forms of Ag in the soil. Efflux rate of Ag in the worm was 2-3 faster than those of Zn, but there were no significant difference among their chemical forms. Subcellular partitioning of Zn and Ag was similar among their chemical forms. Sequential extraction was not a good predictor or bioavailability of nanoparticles in soil.