Innovative tools for testing nanoparticle toxicity
EU researchers designed the ‘Development of an integrated platform for nanoparticle analysis to verify their possible toxicity and the eco-toxicity’ (DIPNA) project to contribute a number of technological innovations for evaluating NP toxicity including methods for depositing NPs on cell cultures, repeated spraying of dry NPs in air, monitoring cellular changes and measuring potential toxicity. The researchers analysed four NPs, cobalt, gold, cerium and iron oxide, and evaluated them when applied both in wet suspension and in dry state. This was done on seven types of standard cell lines used for assays, six from humans and one mouse-derived. Project partners saw no effects on viability, capacity for proliferation or induction of programmed cell death (apoptosis) on any of the cell lines for any of the four NPs applied in either of the two states. In addition, there were no dose-dependent effects on the immunological biomarkers selected (which would indicate an immune response specific to the applied substance) in the time frame evaluated and for the in vitro tests. Finally, the researchers did not observe any change in expression of inflammation-related genes after acute or chronic exposure to NPs. The researchers also conducted an assay to evaluate the effect of NP exposure on the production of free radicals (reactive oxygen species (ROS)) that, despite their many positive roles, can have negative effects on cell function including damaging DNA and RNA and participating in apoptosis. Only cobalt NPs produced a dose-dependent increase in free radicals, most likely explained by the known release of toxic cobalt ions in culture. The DIPNA project team thus made a number of important contributions to urgently needed development of NP toxicology analysis. Further research using NPs in tissue samples, animals and eventually humans will help to make more definite conclusions about their toxicity. Although the field of NP toxicology is in its infancy, it must mature quickly in order to match the pace of nanotechnology development and ensure the safety of workers, end users and the environment. DIPNA researchers provided a number of tools to spur development in this direction.
