E.J. Petersen, T.B. Henry, J. Zhao, R.I. MacCuspie, T.L. Kirschling, B. Xing, M.A. Dobrovolskaia, V. Hackley, J.C. White
National Institute of Standards and Technology, US
artifacts, nanotoxicology, nano-EH&S
Novel physicochemistries of engineered nanomaterials (ENMs) offer considerable commercial potential for new products and processes, but also the possibility of unforeseen and negative consequences upon ENM release into the environment. Investigations of ENM ecotoxicity have revealed that the unique properties of ENMs and a lack of appropriate test methods can lead to results that are inaccurate or not reproducible. The occurrence of spurious results or misinterpretations of results from ENM toxicity tests (defined here as experimental artifacts) that are unique to investigations of ENMs (as opposed to traditional toxicants) have been reported, but have not yet been systemically reviewed. Our objective in this presentation is to highlight artifacts that can occur at each step of ecotoxicity testing: procurement or synthesis of the ENMs and assessment of potential toxic impurities such as metals or endotoxins, ENM storage, dispersion of the ENMs in the test medium, direct interference with assay reagents and indirect effects such as nutrient depletion during the assay, and assessment of the ENM biodistribution in organisms. Examples from studies published in the literature will be discussed to illustrate specific potential artifacts.