Genotoxicity of TiO2 Nanoparticles in Four Different Human Cell Lines (A549, HEPG2, A172 and SH-SY5Y).

Fátima Brandão,Maria João Bessa,Eduardo Pásaro,Blanca Laffon,Natalia Fernández-Bertólez,Fernanda Rosário,Sónia Fraga,João Paulo Teixeira,Carla Costa,Vanessa Valdiglesias

doi:10.3390/nano10030412

Abstract

Titanium dioxide nanoparticles (TiO2 NPs) have a wide variety of applications in many consumer products, including as food additives, increasing the concern about the possible hazards that TiO2 NPs may pose to human health. Although most previous studies have focused on the respiratory system, ingestion must also be considered as an important exposure route. Furthermore, after inhalation or ingestion, TiO2 NPs can reach several organs, such as the liver, brain or lungs. Taking this into consideration, the present study focuses on the uptake and potential genotoxicity (micronuclei induction) of TiO2 NPs on four human cell lines of diverse origin: lung cells (A549), liver cells (HepG2), glial cells (A172) and neurons (SH-SY5Y), using flow cytometry methods. Results showed a concentration-, time- and cell-type- dependent increase in TiO2 NPs uptake but no significant induction of micronuclei in any of the tested conditions. Data obtained reinforce the importance of cell model and testing protocols choice for toxicity assessment. However, some questions remain to be answered, namely on the role of cell culture media components on the agglomeration state and mitigation of TiO2 NPs toxic effects.

Highlights

Titanium dioxide (TiO2) nanoparticles (NPs) are produced in large scale for use in a wide range of applications [1]
In order to clarify the genotoxic potential of TiO2 NPs and how this relates to the cell uptake ability, the present study focuses on the internalization and MN induction of TiO2 NPs on four human cell lines of diverse origin: A549, HepG2, A172 and SH-SY5Y
Our data demonstrate that NP uptake depends on the concentration, time and cell type

Summary

Introduction

Titanium dioxide (TiO2) nanoparticles (NPs) are produced in large scale for use in a wide range of applications [1]. This extensive utilization of TiO2 NPs raises questions about their safety in the context of intentional and unintentional human exposure, both occupational and environmental. Most previous in vitro studies investigating TiO2 safety have focused on the respiratory system, since inhalation represents the most significant route of exposure to these nanoparticles, mainly in occupational settings [1]. Dermal exposure, ingestion, or intraperitoneal or intravenous administration (for medical applications), TiO2 NPs can reach systemic circulation and be distributed and accumulated in several organs, such as lungs, liver, kidneys, spleen or even brain [1]

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Results

Conclusion