[WATER]Quantifying base-line titanium oxide manufactured nanoparticle concentrations in the aquatic environment

Nanoscience and nanotechnology are concerned with the nanoscale which is usually defined as being between 1 and 100 nm in size. The synthesis and use of nanoparticles and other nanomaterials (NMs) are significant parts of nanotechnology and there are clearly many economic, environmental and social benefits from the use of NMs as detailed in recent reports from Royal Society and Royal academy of Engineering and the Royal Commission for Environmental Pollution (http://www.nanotec.org.uk/finalReport.htm; http://www.nanotec.org.uk/finalReport.htm) in energy, in healthcare, consumer products and in other sectors. However, use of NMs, particularly on the vast scale at which is currently occurring and projected for the future, has led to concerns about human and environmental health effects from the bodies mentioned and from others such as the EU SCENIHR (http://ec.europa.eu/health/ph_risk/committees/04_scenihr/docs/scenihr_o_012.pdf) and more widely e.g. Wiesner et al (2006), Owen and Handy (2007), Klaine et al (2008). Ideally, we require full exploitation of the benefits of nanotechnology while ensuring the environment is not adversely affected. An initial important step forward in determining environmental risk is the identification, quantification and characterisation of nanoparticles in real environmental systems. This issue is seen as important in policy terms; of the 19 Research Objectives (ROs) produced by the UK government (DEFRA's Nanotechnology Research Coordination Group http://www.defra.gov.uk/environment/nanotech/research/pdf/nanoparticles-riskreport07.pdf), number 9 is: Optimise, develop and apply technologies that enable the measurement of exposure to nanoparticles in soil and water. Further, such issues were fully recognised at a recent international workshop co-organised by the applicants (Alvarez et al, 2009) where appropriate analysis and metrology was seen as perhaps the key bottleneck to advancing environmental nanoparticle research. Aims and Objectives The overall aim is to generate data on the likely concentrations of titanium dioxide nanoparticles in real environmental aquatic systems. Specific objectives are: 1) To synthesise a set of well controlled isotopically modified titania NPs which will be used as tracers in laboratory based experiments. 2) To characterise fully these and commercially obtained titania NPs. 3) To compare properties of natural and manufactured titania NPs. 4) To quantify total titanium and titania concentrations in laboratory and natural systems. 5) To estimate the concentrations of manufactured NPs using appropriate metrics.