Mapping the Decadal (2009-2018) Research Landscape of Nanotoxicity: Insights from a Bibliometric Study

Nanomaterials (NMs) have wide applications in industrial and household areas, and possibilities of exposure to NMs are increasing, prompting considerable concerns about safety issues related to them. This paper describes the research landscape of nanotoxicity over the past ten years by adopting bibliometric methods. Annual, regional, and institutional distributions, as well as regional/institutional impact of literature on nanotoxicity were analyzed. Both quantitative and citation-based analyses were carried out to reveal the research hotspots. Results showed that cytotoxicity was the most concerned issue in the application of NMs, especially in imaging, diagnosis, and therapy. There were also a large number of studies on ecotoxicity, oxidative stress, apoptosis, genotoxicity, inflammation, and reproductive toxicity caused by NMs. NMs such as Ag, Au, graphene-based materials (GBMs), carbon nanotubes (CNTs), TiO2, SiO2, etc. were the most studied materials. Moreover, a growing number of both in vivo and in vitro studies involving NMs have been carried out in the past ten years. Mammalian models, such as mouse, human and rat, were the most studied models. A Sankey diagram between study types and experimental models showed that in vivo studies exceeded in vitro studies for some well-established animal models. Yet in-depth in vivo studies regarding interactions of NMs within human systems were still essential. With rapid development of nanotechnology, toxic and safety issues on NMs need to be addressed more specifically in future research.