New characterization factors for titanium dioxide

New characterization factors have been calculated to enable more realistic lifecycle assessments (LCAs) for products containing titanium dioxide (TiO2) nanoparticles. LCAs help researchers assess environmental impacts associated with all the stages of a product's life from raw material extraction through materials processing, manufacture, distribution, use, repair and maintenance, and disposal or recycling. Chemical emissions over a product's lifecycle are translated to show potential effects on ecosystems and human health using characterization factors, or comparative toxicity potentials (CTPs), from lifecycle impact assessment (LCIA) methods. 

According to a team led by Alexis Laurent from the Technical University of Denmark, there are currently not enough LCA studies to adequately measure the possible toxic effects of released nanoparticles. For this reason, researchers adapted a model called USEtox to combine fate, exposure, and effects of more than 2,000 chemicals to derive CTPs for LCA studies. They then put this data into a model to find CTPs for titanium dioxide nanoparticles. Their research took into account their impacts on freshwater ecotoxicity and human health resulting from emissions to air, water and soil. 

For future assessment of potential toxic impacts of TiO2 nanoparticles in LCA studies, the researchers recommend the use of their calculated CTP.