Mechanisms Underlying Nanomaterial Effects in Complex Media: How to avoid putting the cart before the horse

Thursday, February 21, 2013

Presenter

Greg Lowry

Abstract: The intrinsic properties of many engineered nanomaterials (ENMs) afford them extraordinary novel properties and reactivity. Correlating intrinsic ENM properties to their environmental impacts is the goal of nanotechnology environmental health and safety research.  However, extrinsic properties of nanomaterials, i.e. those that are determined in part by the environment conditions and solution composition such as solubility or electrophoretic mobility will determine their fate.  Thus, the nanomaterial properties alone cannot determine their behavior.  Environmental properties must be considered.  The past four years of CEINT research has demonstrated a complex interplay between a nanomaterial’s properties and the environmental conditions (e.g. redox, amounts and types of organic matter) and corresponding transformations that those materials undergo.  These transformations, in turn, greatly affect and the material’s toxicity to a range of test organisms. Incomplete understanding of these interactions makes predictions of nanomaterial behaviors in natural environments from intrinsic ENM properties intractable at this time.  An alternative approach is to identify key process variables that determine behavior, e.g. attachment efficiency, and then identify the ENM intrinsic properties that affect those process variables.  This talk will present results from laboratory and field scale studies within CEINT identifying these process variables, and then discuss how the intrinsic properties of the particles determine those process variables.