Physicochemical properties of engineered nanomaterials that influence their nervous system distribution and effects.

This critical review examines in vitro and in vivo evidence for the influence of engineered nanomaterial (ENM) physicochemical properties on their distribution into, and effects on, the nervous system. Nervous system applications of ENMs; exposure routes and potential for uptake; the nervous system and its barriers to ENM uptake; and the mechanisms of uptake into the nervous system and overcoming those barriers are summarized. The findings of English-language publications of studies that included at least two variations of an ENM physicochemical property and reported results of their pharmacokinetic and/or pharmacodynamic interaction with the nervous system that differed as a function of ENM physicochemical property(ies) are summarized in Supplementary Materials. A summary conclusion is drawn for each of the physicochemical properties on the strength of the evidence that it influences ENM-nervous system interaction.