This month, the EPA published the “Framework for Metals Risk Assessment,” which examines the special attributes and behaviors of metals and metal compounds from the perspective of their effects on human health and the environment, and recommends strategies for future research by EPA risk assessors. As concentrations of environmental metals varies around the country, the report emphasizes the importance of establishing “metalloregions,” or regional standards for specific areas in the country for certain kinds of metals. Many metals are brought into the environment as mixtures, and according to the report, research on a given metal’s effects needs to account for the presence of varying quantities of other metals. The study also highlights the importance of determining metal speciation in soils and sediments, for metals may change species, or valence state, as a result of biological or chemical processes. The assessment recommends further development of methods to determine the bioavailability and bioaccumulation