Institute of Urban Environment Reports Findings in Nanoparticles (Coexistence of silver and titanium dioxide nanoparticles: Enhancing or reducing environmental risks?)
By a News Reporter-Staff News Editor at Life Science Weekly -- Data detailed on Nanoparticles have been presented. According to news reporting originating in Xiamen, People's Republic of China, by NewsRx journalists, research stated, "Due to their bactericidal and photocatalytic characteristics, silver nanoparticles (Ag NPs) and titanium dioxide nanoparticles (TiO2 NPs) are widely used in the fields of environment and physiology. Once these untreated nanoparticles are released into an aquatic environment and encounter one another, there is more uncertainty about their fate and ecotoxicological risks compared with the single nanoparticles."
The news reporters obtained a quote from the research from the Institute of Urban Environment, "To expand our knowledge of the health and environmental impacts of nanoparticles, we investigated the possible risk of the co-existence of TiO2 NPs and Ag NPs in an aquatic environment using ciliated protozoa (Tetrahymena pyriforrnis) as an aquatic animal model. In this study, silver ion (Ag+) release and physicochemical properties, as well as their effect on oxidative stress biomarkers, were monitored. Continuous illumination (12,000 lx) led to the 20.0% decrease in Ag+ release in comparison with dark conditions, while TiO2 NPs and continuous illumination resulted in decreasing the Ag+ concentration to 643% in contrast with Ag NPs-only suspensions. Toxicity tests indicated that different illumination modes exerted distinct effects of TiO2 NPs on the toxicity of Ag NPs: no effects, antagonism and synergism in dark, natural light and continuous light, respectively. In the presence of 1.5 mg/L (18.8 p.,M) TiO2 NPs, the toxicity of 1.5 mg/L (13.9 mu M) Ag NPs was reduced by 28.7% and increased by 6.93% in natural light and 12,000 lx of continuous light, respectively. After culturing in 12,000 lx continuous light for 24 h, SOD activity of the light control surged to 1.96 times compared to the dark control (P < 0.001). TiO2 NPs induced a reduction of CAT activity by an average of (36.1 1.7) % in the light. In the natural light reductions in the toxicity of Ag, NPs decrease Ag+ concentrations via adsorption of Ag* onto TiO2 NPs surfaces. The enhancement of Ag NPs toxicity can contribute to the formation of activated Ti02-Ag NPs complexes in continuous light. The existence of TiO2 NPs in various illumination modes changed the surface chemistry of Ag NPs and then led to different toxicity effects."
According to the news reporters, the research concluded: "TiO2 NPs reduce the environmental risks of Ag NPs in natural light, but in continuous light, TiO2 NPs enhance the environmental risks of Ag NPs."
For more information on this research see: Coexistence of silver and titanium dioxide nanoparticles: Enhancing or reducing environmental risks? Aquatic Toxicology, 2014;154():168-175. Aquatic Toxicology can be contacted at: Elsevier Science Bv, PO Box 211, 1000 Ae Amsterdam, Netherlands. (Elsevier - www.elsevier.com; Aquatic Toxicology - www.elsevier.com/wps/product/cws_home/505509)
Our news correspondents report that additional information may be obtained by contacting X.Y. Zou, Chinese Academy Sci, Inst Urban Environm, Xiamen 361021, People's Republic of China. Additional authors for this research include J.P. Shi and H.W. Zhang (see also Nanoparticles).
Keywords for this news article include: Xiamen, People's Republic of China, Asia, Chemicals, Chemistry, Emerging Technologies, Light Metals, Nanoparticle, Nanoparticles, Nanotechnology, Titanium Dioxide
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC