For these reasons, CBEN’s work to use nanomaterials in water treatment has three important features. First, we focus on treatment needs that have no effective technical solution; this involves both a selection of a challenging contaminant (e.g., arsenic) as well as a setting (e.g., point-of-use) that represents an unsolved problem. Second, we invest in basic research (with Theme 1) to improve scale-up and low-impact manufacturing processes for materials that have demonstrated promise. Finally, we elevate the study of environmental and health impacts of engineered nanoparticles to a center-wide objective. Thus, Theme 3 research has an “applications” focus that develops and tests new materials for water purification, and an “implications” side that takes a proactive stance on risk assessment. Theme 3 balances its funding equally between the applications and implications work, a decision supported by the opinions of many site visitors and outside committees.
The implications projects in Theme 3 are all working toward increasing our understanding of the risks of engineered nanoparticles released into aqueous environments. Ultimately risk management will require quantitative models for a variety of nanotechnology use and release scenarios; CBEN is working through workshops and other community-building activities to link its fundamental science to the appropriate partners for this effort. The center’s program will develop the foundation data and frameworks for approaching the risk involved with aqueous release of model engineered nanoparticles. Ultimately this will feed into a comprehensive environmental risk assessment paradigm, consisting of hazard identification, toxicity assessment, exposure assessment, and risk characterization. This Theme 3 activity uses nanotoxicology outputs -now from Theme 1- and provides the information and conceptual models needed to understand how engineered nanomaterials migrate and behave in the environment. Ultimately, this information will be useful for mitigating and preventing environmental and public health impacts of engineered nanoparticles released to aqueous systems.
As in past years, we are continuing to develop nanomaterials to attack the removal of organic contaminants in highly contaminated aquifers; to reduce arsenic contamination for low-energy point-of-use needs; and to develop novel approaches to disinfection and microbial control. These areas define the titles of our three highly interactive projects for nano-enabled water treatment (termed here NEWT). Within this structure, two of the projects are evolving quickly toward larger-scale testing (test beds): 1) arsenic removal from drinking water, which will take advantage of the high specific area of iron-oxide nanoparticles as highly efficient and cost-effective arsenic sorbents that are amenable for magnetic separation, and 2) the destruction of particularly challenging organic contaminants in water that must be removed to a very low level using high-performance bimetallic core/shell nanoparticles. Current approaches to these problems are only marginally effective and relatively costly. Thus, our proof-of-principle applications represent environmentally-benign innovations that offer substantial opportunity for commercialization.