Toxicological Effects of Metal Oxide Nanomaterials - Safety of Nanomaterials along Their Lifecycle - page 163

TABLE 8.2 ( continued )
Summary of Effects of Metal Oxide Nanoparticles on Cultured or Primary
Cells

Property
Involved Nanoparticle Effect Cell Lines Tested Reference

ZrO 2 .amino Cell viability/

metabolic activity

RLE-6TN Surface

modification

nanoGEM, final
report

TiO 2 Genotoxicity MEF mouse primary

embryo fibroblasts

Xu et al. 2009

ZnO Genotoxicity HepG2 Sharma,

Anderson, and
Dhawan 2012

TiO 2 Genotoxicity BEAS-2B Size/surface area Gurr et al. 2005

ZnO Genotoxicity Primary nasal mucosa

cells

Size/surface area Hackenberg et al.

2011b

Rutile TiO 2 ,
anatase TiO 2

Genotoxicity HepG2 Crystalline

structure

Petkovic et al.
2011

SiO 2 .naked,
SiO 2 .phosphate

Genotoxicity 3D bronchial models

EpiAirway TM ,
MatTEK

Surface
modification

nanoGEM, final
report

TiO 2 Effects on gene

expression

BEAS-2B Chemical

composition

Park et al. 2008b

TiO 2 (P25) Inflammatory

response

A549 Size/surface area Singh et al. 2007

Rutile TiO 2 ,
anatase TiO 2

Inflammatory
response

A549, HDF Crystalline

structure

Sayes et al. 2006

embryo fibroblasts (MEF) for ZnO and SiO 2 nanoparticles (Yang et al. 2009). Both
nanoparticle types induced significant ROS generation in a dose-dependent manner,
however, ZnO displayed much stronger effects than SiO 2 . Since the SiO 2 and ZnO
nanoparticles used in this study had a similar crystal shape and particle size this
further suggests that the chemical composition has an impact on ROS generation
(Yang et al. 2009). ZnO nanoparticles also induced oxidative stress in RAW 264.7
macrophages and BEAS-2B bronchial cells (Xia et al. 2008). However, it is not yet
clear whether ZnO nanoparticles directly induced the formation of ROS or if ROS
was formed as a consequence of apoptotic cell death as it was observed recently
in Jurkat cells exposed to ZnO nanoparticles (Buerki-Thurnherr et al. 2013). It is
well documented that ZnO nanoparticles display solubility in aqueous solutions
and recent evidence suggests that detrimental effects of ZnO nanoparticles can be
mainly attributed to dissolved zinc ions (Gilbert et al. 2012; Buerki-Thurnherr et al.
2013; Kao et al. 2012; Xia et al. 2008; Cho et al. 2011).
A correlation between the crystalline structure and the ROS generating capacity
has been found for TiO 2 nanoparticles (Sayes et al. 2006). In dermal fibroblasts, rutile
TiO 2 particles produced two orders of magnitude less ROS than anatase TiO 2 par-
ticles of similar size (Sayes et al. 2006). However, anatase TiO 2 nanoparticles with an