Details

Autor(en) / Beteiligte

• Gomez‐Gonzalez, Miguel A.
• Rehkämper, Mark
• Han, Zexiang
• Ryan, Mary P.
• Laycock, Adam
• Porter, Alexandra E.

Titel

ZnO Nanomaterials and Ionic Zn Partition within Wastewater Sludge Investigated by Isotopic Labeling

Ist Teil von

• Global challenges, 2022-03, Vol.6 (3), p.2100091-n/a

Ort / Verlag

Germany: John Wiley & Sons, Inc

Erscheinungsjahr

2022

Quelle

Wiley Online Library

Beschreibungen/Notizen

• The increasing commercial use of engineered zinc oxide nanomaterials necessitates a thorough understanding of their behavior following their release into wastewater. Herein, the fates of zinc oxide nanoparticles (ZnO NPs) and ionic Zn in a real primary sludge collected from a municipal wastewater system are studied via stable isotope tracing at an environmentally relevant spiking concentration of 15.2 µg g−1. Due to rapid dissolution, nanoparticulate ZnO does not impart particle‐specific effects, and the Zn ions from NP dissolution and ionic Zn display indistinguishable behavior as they partition equally between the solid, liquid, and ultrafiltrate phases of the sludge over a 4‐h incubation period. This work provides important constraints on the behavior of engineered ZnO nanomaterials in primary sludge—the first barrier in a wastewater treatment plant—at low, realistic concentrations. As the calculated solid–liquid partition coefficients are significantly lower than those reported in prior studies that employ unreasonably high spiking concentrations, this work highlights the importance of using low, environmentally relevant doses of engineered nanomaterials in experiments to obtain accurate risk assessments. The fate of ZnO nanomaterials in an untreated wastewater sludge at an environmentally relevant concentration is studied. Nanoparticulate ZnO dissolves rapidly within the acidic sludge. ZnO nanoparticles and ionic Zn show identical partitioning within the sludge. This suggests that the ecotoxicity of the ZnO nanomaterials at the µg g−1 level is entirely attributable to the dissolved Zn2+ ions.