Comparison of TiO2 nanoparticle and graphene–TiO2 nanoparticle composite phototoxicity to Daphnia magna and Oryzias latipes

Authors

Shibin Li, U.S. Environmental Protection AgencyFollow
Xuan Pan, Texas Tech University
Lindsay K. Wallis, U.S. Environmental Protection Agency
Zhaoyang Fan, Texas Tech University
Zuliang Chen, Fujian Normal University, Fujian Province, China
Stephen A. Diamond, Nanosafe Inc., Blacksburg, VA

Date of this Version

2014

Citation

Chemosphere 112 (2014) 62–69

Comments

This article is a U.S. government work, and is not subject to copyright in the United States.

Abstract

With a dramatic rise in complexity, needs of nanotoxicology research go beyond simple forms of nanomaterials. This study compared the phototoxicity of nano-TiO2 and graphene–TiO2 nanocomposite (GNP). GNP was synthesized based on a hydrothermal method, which simultaneously performed the reduction of graphene oxide and nano-TiO2 loading. A series of acute toxicity tests of nano-TiO2, graphene and GNP was performed on two aquatic organisms, Daphnia magna and Oryzias latipes. Fast and substantial agglomeration and sedimentation of nanoparticles in test media and surface attachment of nano-TiO2 and GNP on D. magna surface was observed. Similar phototoxicity of nano-TiO2 andGNPfor both species existed, though compared with nano-TiO2, GNP had a 2.3-fold increase in visible light photocatalytic ROS generation. In summary, this study demonstrated the significance of illumination spectrum, particle behavior, and species sensitivity on nanophototoxicity, and the needs for research on increasingly sophisticated functional materials.