Predicting the toxicity of metal mixtures
The toxicity of single and multiple metal (Cd, Cu, Pb, and Zn) solutions to trout is predicted using an approach that combines calculations of: (1) solution speciation; (2) competition and accumulation of cations (H, Ca, Mg, Na, Cd, Cu, Pb, and Zn) on low abundance, high affinity and high abundance, low affinity biotic ligand sites; (3) a toxicity function that accounts for accumulation and potency of individual toxicants; and (4) biological response. The approach is evaluated by examining water composition from single metal toxicity tests of trout at 50% mortality, results of theoretical calculations of metal accumulation on fish gills and associated mortality for single, binary, ternary, and quaternary metal solutions, and predictions for a field site impacted by acid rock drainage. These evaluations indicate that toxicity of metal mixtures depends on the relative affinity and potency of toxicants for a given aquatic organism, suites of metals in the mixture, dissolved metal concentrations and ratios, and background solution composition (temperature, pH, and concentrations of major ions and dissolved organic carbon). A composite function that incorporates solution composition, affinity and competition of cations for two types of biotic ligand sites, and potencies of hydrogen and individual metals is proposed as a tool to evaluate potential toxicity of environmental solutions to trout.
Citation Information
Publication Year | 2013 |
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Title | Predicting the toxicity of metal mixtures |
DOI | 10.1016/j.scitotenv.2013.07.034 |
Authors | Laurie S. Balistrieri, Christopher A. Mebane |
Publication Type | Article |
Publication Subtype | Journal Article |
Series Title | Science of the Total Environment |
Index ID | 70177027 |
Record Source | USGS Publications Warehouse |
USGS Organization | Geology, Minerals, Energy, and Geophysics Science Center |