Assessing the dietary bioavailability of metals associated with natural particles: Extending the use of the reverse labeling approach to zinc

Environmental Science & Technology
By: , and 

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Abstract

We extend the use of a novel tracing technique to quantify the bioavailability of zinc (Zn) associated with natural particles using snails enriched with a less common Zn stable isotope. Lymnaea stagnalis is a model species that has relatively fast Zn uptake rates from the dissolved phase, enabling their rapid enrichment in 67Zn during the initial phase of labeling. Isotopically enriched snails were subsequently exposed to algae mixed with increasing amounts of metal-rich particles collected from two acid mine drainage impacted rivers. Zinc bioavailability from the natural particles was inferred from calculations of 66Zn assimilation into the snail’s soft tissues. Zinc assimilation efficiency (AE) varied from 28% for the Animas River particles to 45% for the Snake River particles, indicating that particle-bound, or sorbed Zn, was bioavailable from acid mine drainage wastes. The relative binding strength of Zn sorption to the natural particles was inversely related to Zn bioavailability; a finding that would not have been possible without using the reverse labeling approach. Differences in the chemical composition of the particles suggest that their geochemical properties may influence the extent of Zn bioavailability.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Assessing the dietary bioavailability of metals associated with natural particles: Extending the use of the reverse labeling approach to zinc
Series title Environmental Science & Technology
DOI 10.1021/acs.est.6b06253
Volume 51
Issue 5
Year Published 2017
Language English
Publisher ACS Publications
Contributing office(s) National Research Program - Western Branch
Description 8 p.
First page 2803
Last page 2810