The widespread use of lead (Pb) shot in shooting activities, including at former shooting ranges, continues to pose environmental risks. The La Crosse River Marsh (located in Wisconsin, USA) is a biologically diverse urban riparian wetland with a legacy of Pb-contaminated sediment resulting from its use as a trap shooting range from 1929–1963. Within the shot fall zone, shot densities exceed 43,000 pellets/m2 and surface sediments exceed 25,000 mg/kg in some areas. This study used the Zebrafish as a model to determine the acute toxicity of these contaminated sediments. Zebrafish were exposed to sediments containing approximately 13 to 13,450 mg/kg Pb for 5 days (8–120 hr post-fertilization). The toxic responses to sediments were non-monotonic. Only exposure to sediments containing “mid-range” concentrations of Pb (4580 mg/kg) induced mild skeletal malformations and a sluggish C-start response indicating that Pb was marginally bioavailable. Expression of δ-aminolevulinic acid dehydratase (ALA-D) also indicated the potential for uptake of Pb from sediments. Our findings suggest that Pb within the La Crosse River Marsh sediments is not readily bioavailable to Zebrafish, and while this metal poses a minimal acute toxicological risk, toxicity due to chronic exposure of low concentrations of Pb is possible. Further, our data demonstrated that induction of ALA-D gene expression in Zebrafish embryos shows promise as an alternative to ALA-D enzyme activity as a biomarker for acute Pb exposure under lab conditions.
|Original language||English (US)|
|Number of pages||15|
|Journal||Journal of Toxicology and Environmental Health - Part A: Current Issues|
|State||Published - Sep 17 2018|
Bibliographical noteFunding Information:
This work was supported by EPA Urban Water’s grant #UW00E01025, UWL River Studies Center, and UWL Faculty Research Grant. We thank Yer Lor and Courtney Schneider for their assistance with experiments, and Kristofer Rolfhus and anonymous reviewers for their insights on our findings. Authors declare no conflict of interest.
This work was supported by the US EPA Urban Water’s grant [#UW00E01025]; UW La Crosse River Studies Center.
© 2018, © 2018 Taylor & Francis.
Copyright 2018 Elsevier B.V., All rights reserved.
- lead toxicity
- trapshooting range
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