Determination of mutagenicity and genotoxicity of indium tin oxide nanoparticles using the Ames test and micronucleus assay

Abstract

In this study, the mutagenicity and genotoxicity of indium tin oxide (ITO) nanomaterial were assessed using two standard genotoxicity assays, the Salmonella reverse mutation assay (Ames test) and the in vitro micronucleus (MN) assay. Seven different concentrations (12.5, 25, 50, 75, 100, 125, and 150 µg/plate) of this nanomaterial were tested using the Ames test on the TA98 and TA100 strains in the presence and absence of the S9 mixture. At all the concentrations tested, this substance did not significantly increase the number of revertant colonies compared with the control with or without S9 mixture. The genotoxic effects of ITO were investigated in human peripheral lymphocytes treated with 125, 250, 500, and 750 µg/ml concentrations of this substance for 24- and 48-h treatment periods using an MN test. Nuclear division index (NDI) was also calculated in order to determine the cytotoxicity of ITO. It was determined that ITO increased MN frequency in the 750 µg/ml concentration in 24- and 48-h treatments. In addition, ITO dose dependently decreased the NDI significantly for two treatment periods.

The toxicology of indium tin oxide

“…Therefore, the validity and reliability of test results indicating a potential for genotoxic/DNA damaging effects is difficult to assess. There are indications that the effects might be secondary, most likely as a result of ROS induction (Akyıl et al, 2015;Badding et al, 2014;Cigerci et al, 2015;Lison et al, 2009;Tabei et al, 2015Tabei et al, , 2016.…”

“…With the exception of the Ames test (Akyıl et al, 2015), all the other studies were not performed according to validated and adopted guidelines and/or have not been described in sufficient detail to allow the assessment of their validity. Solubility in the various vehicles used was mostly not determined; this may be crucial in view of the stated poor solubility/insolubility.…”

“…With the exception of the Salmonella reverse mutation assay (Ames test) with and without metabolic activation (S9 mix) by Akyıl et al (2015), which, however, did not include several strains recommended by OECD guideline 471, such as TA 1535, TA 1537 or TA 102, all other tests were performed with non-validated methods.…”

“…The nuclear division index (NDI), calculated in order to determine the cytotoxicity of UITO NP, was dosedependently and significantly decreased in both treatment periods (Akyıl et al, 2015).…”

Indium oxide nanoparticles induce lung intercellular toxicity between bronchial epithelial cells and macrophages

“…In vitro, an indium compound was found to decrease cell viability, induce oxidative stress damage (Ahamed, Akhtar, Khan, Alhadlaq, & Aldalbahi, 2017; Alkahtane, 2015; Badding, Stefaniak, Fix, Cummings, & Leonard, 2014), promote DNA cleavage and increase the micronuclei frequency (Akyil, Eren, Konuk, Tepekozcan, & Saglam, 2016; Lin, Yang, Li, Chang, & Kuan, 2013). Ahamed et al have shown that IO nanocubes induce cell viability reduction and cell membrane damage in human lung epithelial (A549) cells in a dose‐ and time‐dependent manner (Ahamed et al, 2017).…”