Toxicology of silica nanoparticles: an update

Arch Toxicol. 2017 Sep;91(9):2967-3010. doi: 10.1007/s00204-017-1993-y. Epub 2017 Jun 1.


Large-scale production and use of amorphous silica nanoparticles (SiNPs) have increased the risk of human exposure to SiNPs, while their health effects remain unclear. In this review, scientific papers from 2010 to 2016 were systematically selected and sorted based on in vitro and in vivo studies: to provide an update on SiNPs toxicity and to address the knowledge gaps indicated in the review of Napierska (Part Fibre Toxicol 7:39, 2010). Toxicity of SiNPs in vitro is size, dose, and cell type dependent. SiNPs synthesized by wet route exhibited noticeably different biological effects compared to thermal route-based SiNPs. Amorphous SiNPs (particularly colloidal and stöber) induced toxicity via mechanisms similar to crystalline silica. In vivo, route of administration and physico-chemical properties of SiNPs influences the toxicokinetics. Adverse effects were mainly observed in acutely exposed animals, while no significant signs of toxicity were noted in chronically dosed animals. The correlation between in vitro and in vivo toxicity remains less well established mainly due to improper-unrealistic-dosing both in vitro and in vivo. In conclusion, notwithstanding the multiple studies published in recent years, unambiguous linking of physico-chemical properties of SiNPs types to toxicity, bioavailability, or human health effects is not yet possible.

Keywords: Amorphous silica nanoparticles; Colloidal; Oxidative stress; Pyrogenic; Stöber; Toxicity.

Publication types

  • Review

MeSH terms

  • Animals
  • Autophagy / drug effects
  • Cell Culture Techniques
  • DNA Damage / drug effects
  • Endothelium, Vascular / drug effects
  • Endothelium, Vascular / physiopathology
  • Humans
  • Immune System / drug effects
  • Inhalation Exposure
  • Mutagenicity Tests / methods
  • Nanoparticles / administration & dosage
  • Nanoparticles / toxicity*
  • Neurotoxicity Syndromes / etiology
  • Oxidative Stress / drug effects
  • Silicon Dioxide / administration & dosage
  • Silicon Dioxide / toxicity*
  • Toxicity Tests / methods


  • Silicon Dioxide