Speciation, Sources and Bioavailability of Copper and Zinc in DoD-Impacted Harbors and Estuaries
Abstract
The response of organisms to metal exposure is dependent on the chemical and physical associations (speciation) as well as the concentration of the respective metal. Metal toxicity is regulated by the biogeochemical environment in which it exists. Therefore total and operationally defined "dissolved" metal concentrations are not necessarily predictive of toxicity or potential risk to the environment. The overarching goal of this SERDP project was to advance our understanding of metal-ligand binding in order to further the development of practical and predictive models of trace metal bioavailability. Our primary speciation focus was on Strong Metal-Binding Ligands and Colloidal Phases. In this project we isolated important metal-ligand pools and characterized the ligands and their metal-binding properties in three contrasting marine estuaries, focusing primarily on Copper (Cu) and to a lesser degree, Zinc (Zn). Chemical measures of metal speciation were linked to bioavailability as quantified in parallel laboratory studies with marine algae. Multiple bioavailability/toxicity endpoints including: (1) cellular budgets of trace metals, (2) molecular biomarkers, and (3) growth characteristics, were measured. For our study systems, we chose three DoD-impacted marine estuaries with major contrasts in ligand source, type, and abundance, as well as significant gradients in trace element levels.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2007
- Accession Number
- ADA470244
Entities
People
- Brian Beard
- David Armstrong
- Degui Tang
- Jocelyn Hemming
- Martin Shafer
Organizations
- University of Wisconsin–Madison