Role of tungstate nanoparticles in the production of ROS and induction of cellular damage.
Dunnick KM; Badding MA; Fix NR; Patete JM; Wong SS; Castranova V; Leonard SS
Toxicologist 2013 Mar; 132(1):371
Alkaline-earth metal tungstate AWO4 (A= Ca, Ba, Sr ) nanoparticles are currently being used in a variety of applications including use as components of medical equipment, optical fibers, gas sensors, and scintillator detectors. Due to tungstate nanoparticle versatility, their manufacturing is expected to increase within the next 10 years. Our ongoing study is designed to examine the effects of tungstate nanoparticle exposure in order to develop safe workplace practices to limit exposure. Electron Spin Resonance (ESR) was used to measure hydroxyl radical (-OH) production of tungstate nanoparticles following incubation with either hydrogen peroxide (H2O2) or RAW 264.7 cells. Additionally, enhanced dark field microscopy was used to assess nanoparticle association and engulfment by RAW cells over multiple time points up to 3 hours. Assays measuring H2O2 production, oxygen consumption, DNA damage and lipid peroxidation were used to assess possible cellular injury following RAW cell incubation with tungstate nanoparticles. Data showed that tungstate nanoparticles are capable of producing -OH in the presence of H2O2 and RAW cells. Further, tungstate nanowires produced significantly greater -OH compared to nanospheres as shown through ESR measurements. Initial dark field microscopy data showed an increase in association between tungstate nanoparticles and cells and a decrease in non-specific binding after 3 hours of exposure. Cellular damage results in conjunction with ESR data will promote an understanding of tungstate nanoparticle toxicity. It is important to understand the damaging effects and free radical production produced by tungstate nanoparticle exposure in order to ensure that accurate toxicity models are developed and to promote proper training in nanoparticle inhalation prevention.
Toxicology; Nanotechnology; Laboratory-testing; Bioassays; Hydroperoxides; Alkaline-earth-metals; Hydroxyl-groups; Free-radicals; Free-radical-generation; Oxygen-uptake; DNA-damage; Lipid-peroxidation; Cell-cultures; Cellular-reactions; Cell-damage; Measurement-equipment; Chemical-binding
The Toxicologist. Society of Toxicology 52nd Annual Meeting and ToxExpo, March 10-14, 2013, San Antonio, Texas