Size-Based Differential Transport, Uptake, and Mass Distribution of Ceria (CeO2) Nanoparticles in Wetland Mesocosms.

Published

Journal Article

Trace metals associated with nanoparticles are known to possess reactivities that are different from their larger-size counterparts. However, the relative importance of small relative to large particles for the overall distribution and biouptake of these metals is not as well studied in complex environmental systems. Here, we have examined differences in the long term fate and transport of ceria (CeO2) nanoparticles of two different sizes (3.8 vs 185 nm), dosed weekly to freshwater wetland mesocosms over 9 months. While the majority of CeO2 particles were detected in soils and sediments at the end of nine months, there were significant differences observed in fate, distribution, and transport mechanisms between the two materials. Small nanoparticles were removed from the water column primarily through heteroaggregation with suspended solids and plants, while large nanoparticles were removed primarily by sedimentation. A greater fraction of small particles remained in the upper floc layers of sediment relative to the large particles (31% vs 7%). Cerium from the small particles were also significantly more bioavailable to aquatic plants (2% vs 0.5%), snails (44 vs 2.6 ng), and insects (8 vs 0.07 μg). Small CeO2 particles were also significantly reduced from Ce(IV) to Ce(III), while aquatic sediments were a sink for untransformed large nanoparticles. These results demonstrate that trace metals originating from nanoscale materials have much greater potential than their larger counterparts to distribute throughout multiple compartments of a complex aquatic ecosystem and contribute to the overall bioavailable pool of the metal for biouptake and trophic transfer.

Full Text

Duke Authors

Cited Authors

  • Geitner, NK; Cooper, JL; Avellan, A; Castellon, BT; Perrotta, BG; Bossa, N; Simonin, M; Anderson, SM; Inoue, S; Hochella, MF; Richardson, CJ; Bernhardt, ES; Lowry, GV; Ferguson, PL; Matson, CW; King, RS; Unrine, JM; Wiesner, MR; Hsu-Kim, H

Published Date

  • September 2018

Published In

Volume / Issue

  • 52 / 17

Start / End Page

  • 9768 - 9776

PubMed ID

  • 30067347

Pubmed Central ID

  • 30067347

Electronic International Standard Serial Number (EISSN)

  • 1520-5851

International Standard Serial Number (ISSN)

  • 0013-936X

Digital Object Identifier (DOI)

  • 10.1021/acs.est.8b02040

Language

  • eng