Graham and I are continuing to work toward the practical implementation of bioavailability based water quality standards for trace metals, in collaboration with European researchers and the European Copper Institute. Together we have been working to develop a method for estimating some of the input parameters for Biotic Ligand Models (BLMs). This recent work outlines an approach for estimating the concentrations of major ions in fresh waters, such as sodium, magnesium, chloride, and sulphate from calcium concentrations meaning that for most BLM predictions analytical data are only required for pH, dissolved organic carbon, and calcium.
This work has recently been accepted for publication in Integrated Environmental Assessment and Management (see link), where the complete article can be accessed by SETAC members.
Link to abstract: http://onlinelibrary.wiley.com/doi/10.1002/ieam.159/abstract