The influence of humic acid on the toxicity of nano-ZnO and Zn2+ to the Anabaena sp.
Article first published online: 12 FEB 2014
Copyright © 2014 Wiley Periodicals, Inc.
How to Cite
Tang, Y., Li, S., Lu, Y., Li, Q. and Yu, S. (2014), The influence of humic acid on the toxicity of nano-ZnO and Zn2+ to the Anabaena sp. Environ. Toxicol.. doi: 10.1002/tox.21964
- Article first published online: 12 FEB 2014
- Manuscript Accepted: 24 JAN 2014
- Manuscript Revised: 21 JAN 2014
- Manuscript Received: 28 SEP 2013
- National Natural Science Foundation of China . Grant Number: 21007048
- Key Projects in the National Science and Technology Pillar Program during the Twelfth Five-Year Plan Period . Grant Number: 2012BAF03B06
- State Key Laboratory of Pollution Control and Resource Reuse Foundation
- natural organic matter;
- ZnO nanoparticles;
This study explored the effects of humic acid (HA) on the toxicity of ZnO nanoparticles (nano-ZnO) and Zn2+ to Anabaena sp. Typical chlorophyll fluorescence parameters, including effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were measured by a pulse-amplitude modulated fluorometer. Results showed that nano-ZnO and Zn2+ could inhibit Anabaena sp. growth with the EC50 (concentration for 50% of maximal effect) of 0.74 ± 0.01 and 0.3 ± 0.01 mg/L, respectively. In the presence of 3.0 mg/L of HA, EC50 of nano-ZnO increased to 1.15 ± 0.04 mg/L and EC50 of Zn2+ was still 0.3 ± 0.01 mg/L. Scanning electron microscopy observation revealed that HA prevented the adhesion of nano-ZnO on the algae cells due to the increased electrostatic repulsion. The generation of intracellular reactive oxygen species and cellular lipid peroxidation were significantly limited by HA. Nano-ZnO had more damage to the cell membrane than Zn2+ did, which could be proven by the malondialdehyde content in Anabaena sp. cells. © 2014 Wiley Periodicals, Inc. Environ Toxicol, 2014.