Grant: Collaborative Research and Development Grants

The Biotic Ligand Model (BLM) is a computational approach for the generation of Water Quality Criteria. In freshwater (FW) environments the BLM approach has been a success for the metals industries, regulatory bodies, & the environment. Using BLM methodologies, appropriate & protective regulatory criteria can be established in a site-specific manner. The US EPA has adopted a BLM approach to assist in the determination of FW copper criteria & regulatory BLMs are under various stages of development for other metals in fresh water, such as Pb, Zn, & Ni. The majority of water on this planet is not fresh water though. The chemistry & biology of both metals & organisms change as salinity increases, & research is needed to test if the BLM framework will be as useful for regulatory purposes at elevated salinities (estuarine to full seawater). It is estimated that 70% of the world's population live in coastal environments & metal impacts in saltwater (SW) environments are potentially significant, with sources from municipal/industrial effluent, building material runoff, plumbing, anti-fouling paints & sometimes directly from mines and auxiliary facilities operating in coastal areas. To date, SW environments have not received as much research attention as FW environments. There is a need for basic SW-specific BLM basic, including physiological mechanisms, chemistry (speciation), lole of organic matter, salinity as well as more test species to expand the species sensitivity distribution. A research team with unique BLM expertise will contribute to the development ofSW BLMs. This research/project will contribute to the development of acute & chronic marine & estuarine BLMs for Cu, Zn, Pb, & Ni. The project will be focused on chemistry & biology of these metals across a range of salinities & dissolved I organic carbon (DOC) gradients. Metal speciation information will be combined with relevant toxicity tests to develop a BLM framework with an emphasis on mechanisms. An understanding of the underlying mechanisms J of toxicity is one of the strengths of existing FW BLMs, & mechanistic aspects will be emphasized in this new initiative.