Environmental fate models of nanoparticles
Scientists launched the EU-funded project 'Nanoparticles fate assessment and toxicity in the environment' (NANOFATE) to evaluate selected high-volume products that are not recycled. Fuel additives, personal care products and antibacterial products are some of these that can end up in the soil or ground water. The team followed two ENPs from each product through their post-production life cycles from environmental entry from used products to waste treatment, to final fate and potential toxicity. Scientists studied particle chemistry and fate of chosen ENPs consisting of silver (Ag), zinc oxide (ZnO) and the fuel additive cerium oxide (CeO2). They produced cobalt-doped ZnO to facilitate fate studies. ENPs were evaluated in both ecotoxicological media and natural systems. Protocols were optimised to produce the most realistic conditions. Initial environmental fate models were developed to predict CeO2 deposition in soils and nano ZnO and Ag as influent to and discharge from sewage treatment plants. Experimental work increased by 50 % the species data points available for use in derivation of species sensitivity distributions as part of the project. The team delivered important data on ecotoxicity and its relationship to factors such as soil pH, coating or not of ENPs, and ageing. Results established acute and chronic toxicity of relevant doses for the environmentally relevant media conditions. The initial models based on assumptions were refined as real data from the current and other projects became available. The final models enabled detailed conclusions about the selected ENPs studied from local to EU region scales. The project produced numerous reports, including on predicted soil contamination levels for each of the selected ENPs, and maps of mean and worst case probable effect concentration for six European river catchments. Scientists also produced a report of phylogenetic and trait-based effects using a species sensitivity distribution approach. Twenty-one peer-reviewed articles and four mass media articles were published, and others are in the pipeline. Outreach to regulatory and standardisation bodies has been extensive. NANOFATE is an environmentally and economically relevant research project. Its results provide stakeholders with the necessary tools, techniques and knowledge to understand and share the risks associated with various ENPs.
Keywords
Nanoparticles, risk assessment, fate assessment, toxicity, environment
