Toxicology of nanomaterials: From toxicokinetics to toxicity mechanisms

Nanotechnology provides enormous momentum for the growth of various fields and contributes a huge number of nanoscale substances either as products or by-products to human society and the environment. However, exposure to various nanomaterials has been reported to elicit toxic effects on diverse organisms, which provokes worries about nanosafety issues and yields the nanotoxicology field. Here, we provide an informative review on this field aiming to further advance the toxicological research and safety evaluation of nanomaterials. Firstly, the toxicokinetics (i.e., absorption, distribution, metabolism, and excretion) of nanomaterials in terms of common exposure routes are introduced. Secondly, we discuss nanomaterial toxicity and the underlying mechanisms on the levels of organs, tissues, cells, and molecules. Because physicochemical properties play a significant role in nanomaterial toxicity, we briefly present how various properties impact nanotoxicity. Following, the major toxicological topics and their corresponding analytical approaches are provided to facilitate the advancement of the nanotoxicology field. Last but not the least, we stress the challenges facing and the possible solutions to fulfill the reliable and efficient safety evaluation of nanomaterials.