Health problems associated with exposure to arsenic (As) from chromated copper[unreadable] arsenate (CCA)-treated wood continue to command world attention. It has been[unreadable] demonstrated that, in addition to As, chromium (Cr) and copper (Cu) also leach at levels[unreadable] potentially toxic to aquatic organisms. Although considerable progress has been made in[unreadable] studying the toxicity of As, the harmful effects of these three elements in mixtures, leached[unreadable] simultaneously are currently unknown. The lack of this information remains one of the major[unreadable] obstacles to assess the potential effects of CCA-treated wood on human health. Our longterm[unreadable] goal is to characterize and ultimately reduce the human health risks associated with[unreadable] exposure to CCA. The principal objective of this research is to understand the leaching and[unreadable] human physiological effects (cell behavior and metabolism) of As, Cr, and Cu associated with[unreadable] CCA-treated wood. The objective will be accomplished by pursuing the following specific[unreadable] aims: (1) Investigate the leaching characteristics of all three toxic elements, As, Cr, and Cu[unreadable] from CCA-treated wood and from the affected soils; (2) Evaluate the effects on aspects of[unreadable] cell physiology of As, Cr, and Cu alone or in mixtures using a model based on human nerve[unreadable] cell cultures (cell lines such as NSC-34, SH-SY5Y, CATH.a, D384 and SK-N-MC); and 3)[unreadable] Determine the effects of soil properties on the cell effects of soil leachate. This study will be[unreadable] guided by the following hypotheses: (1) The potential physiological effects of the leachates[unreadable] associated with CCA-treated wood to human beings is affected by the presence of the three[unreadable] metals derived from CCA and interactions between them and low concentrations of As, Cr,[unreadable] and Cu in these leachates will affect critical aspects of cell metabolism; and (2) The leaching[unreadable] and potential effects of these elements from soils affected by CCA are altered by soil[unreadable] properties. It is expected that this research will provide new and essential information for[unreadable] assessing the effects of the leachates associated with CCA on human beings. These results[unreadable] will allow improved predictions of leaching of As, Cr, and Cu from CCA-treated wood and[unreadable] their transport through soils and, ultimately, evaluations of possible human health impacts[unreadable] associated with the release of these elements. Our results will, therefore, enable us to more[unreadable] accurately assess the environmental and human health impacts of As, Cr, and Cu pollution[unreadable] resulting from CCA applications.