Environmental Risk Assessment of Emerging Contaminants-The Case of Nanomaterials

Risk assessment is a powerful tool to help evaluate potential environmental and health risks of novel materials. However, traditional risk assessment frameworks and methods often face significant challenges when evaluating novel materials due to uncertainties and data gaps. Engineered nanomaterials is one prominent example of new, advanced materials whereby scientists, researchers and decision-makers are still discussing best practices to modify and update risk assessment frameworks after nearly two decades of research. This chapter focuses on how early warning signs within the environmental risk assessment development process for nanomaterials were addressed with a focus on characterizing uncertainty. We shed light on how environmental risk assessment of nanomaterials transitioned from a state of “known unknowns” to data-driven inputs to conducting risk assessments. We also discuss ecotoxicological testing considerations, and in particular how methodological and technical challenges were addressed. Finally, we provide recommendations on how best to transfer identified best practices and knowledge to other emerging technologies and advanced materials.