The need for standardized methods and environmental monitoring programs for anthropogenic nanoparticles

Anthropogenically generated nanoparticles represent a rapidly expanding range of emerging pollutants that have the potential to be released into all phases of environmental media and thus pose an ecotoxicological risk to exposed organisms. Critical to understanding the risks associated with anthropogenic nanoparticle exposure is the ability to qualitatively and quantitatively measure these pollutants in various environmental compartments. In this paper, we present an overview of recent studies that have quantified nanoparticle concentrations in environmental media, and discuss the immediate need for such information in order to appropriately assess the risks to biological species due to potential nanoparticle exposure. Specifically, we issue a challenge to national and international regulatory and research agencies to help develop standard methods, quality assurance tools, and implement environmental monitoring programs for this class of pollutants. We also provide an overview for a monitoring program that is based on historical regulatory criteria and includes a priority based testing program for primary environmental media and biological media susceptible to anthropogenic nanoparticle exposure. Once established, such programs would generate baseline data that could facilitate the environmental risk assessment evaluations that are virtually absent for this class of emerging pollutants.