Toxic Effects of Nano-CuO, Micro-CuO and Cu<sup>2+</sup>on <i>Chlorella</i>sp.

• 作者: Changsheng Peng Jinfen Pan Liyan Wang Mian Wang
• 来源期刊: 环境保护(英文)
• 学科: 医学
• 关键词: NANO-CUO CHLORELLA sp. Toxic effects Photosynthesis OXIDANT stress
• 年，卷（期）: 2013,（1）
• 页码范围: 86-91
• 页数: 6页
• 分类号: R73

摘要

The 96 h acute toxic effects of nano-CuO (N-CuO), micro-CuO (M-CuO) and 2+ on Chlorella sp. were investigated in this paper. The results showed that toxicities decreased in an order of Cu2+>N-CuO>M-CuO. The 96 h EC50 of Cu2+ on Chlorella sp. was 1.06 mg /L, and of N-CuO it was 74.61 mg /L, while no pronounced toxicity was observed when the concentration of M-CuO was lower than 160 mg/L. Further experiments were carried out in order to study the toxicity mechanism of nano-CuO on Chlorella sp.. The results of Cu2+ release from N-CuO showed less than 0.2 mg/L Cu2+ were released, so the release of Cu2+ was not responsible for the toxicity. Further experiments showed N-CuO inhibited formation of Chlorophyll A. Content of Chlorophyll A in the control group was 4.75 mg/108 cells, while it declined to 2.89 mg/108 cells for 160 mg/L N-CuO after 96 h, which indicated that N-CuO could inhibit photosynthesis of Chlorella sp.. Moreover, N-CuO condensed with algal cells. It affected the activity of SOD and POD, indicating that N-CuO could cause oxidant stress to Chlorella sp.. These may be the toxicity mechanism.