A novel multi-isotope tracer approach to test ZnO nanoparticle and soluble Zn bioavailability in joint soil exposures
File(s)acs.est.7b02944.pdf (1.03 MB)
Published version
Author(s)
Type
Journal Article
Abstract
Here we use two enriched stable isotopes, 68Znen and 64Znen (>99%), to prepare 68ZnO nanoparticles (NPs) and soluble 64ZnCl2. The standard LUFA 2.2 test soil was dosed with 68ZnO NPs and soluble 64ZnCl2 to 5 mg kg-1 each, plus between 0 and 95 mg kg-1 of soluble ZnCl2 with a natural isotope composition. After 0, 1, 3, 6 and 12 months of soil incubation, earthworms (Eisenia andrei) were introduced for 72-hour exposures. Analyses of soils, pore waters and earthworm tissues using multiple collector ICP-MS allowed the simultaneous measurement of the diagnostic 68Zn/66Zn, 64Zn/66Zn and 68Zn/64Zn ratios, from which the three different isotopic forms of Zn were quantified. Eisenia andrei was able to regulate Zn body concentrations with no difference observed between the different total dosing concentrations. The accumulation of labelled Zn by the earthworms showed a direct relationship with the proportion of labelled to total Zn in the pore water, which increased with longer soil incubation times and decreasing soil pH. The 68Znen/64Znen ratios determined for earthworms (1.09 ± 0.04), soils (1.09 ± 0.02) and pore waters (1.08 ± 0.02) indicate indistinguishable environmental distribution and uptake of the Zn forms, most likely due to rapid dissolution of the ZnO NPs.
Date Issued
2017-10-10
Date Acceptance
2017-10-10
ISSN
0013-936X
Publisher
American Chemical Society
Start Page
12756
End Page
12763
Journal / Book Title
Environmental Science and Technology
Volume
51
Issue
21
Copyright Statement
ACS AuthorChoice - This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited.
Sponsor
Natural Environment Research Council (NERC)
Science and Technology Facilities Council (STFC)
Engineering & Physical Science Research Council (E
Grant Number
NE/L004968/1
4070103442
EP/P51116X/1
Subjects
MD Multidisciplinary
Environmental Sciences
Publication Status
Published