摘要
随着生产和应用的快速发展,纳米材料通过各种途径进入环境,导致污染的可能大大增加,对其可能产生的环境风险和生物安全值得关注。以斜生栅藻(Scenedesmus oblignus)为指示生物,采用藻类生长抑制、光合色素含量及抗氧化酶活性测定等实验,研究了纳米氧化锌(ZnO)和纳米二氧化钛(TiO2)的毒理学效应。结果显示:纳米ZnO在低浓度时(5mg·L-1)对斜生栅藻生长有显著促进作用,随着浓度升高,逐渐表现为抑制;在最高浓度50mg·L-1时,细胞色素含量减少,蛋白质含量及抗氧化酶活性明显下降,引起显著细胞氧化损伤。纳米TiO2也表现为低浓度(1mg·L-1)促进、高浓度(200mg·L-1)抑制藻类生长的趋势,同时高浓度还导致细胞色素和蛋白质含量减少,抗氧化酶活性明显下降,同样引起氧化胁迫效应。研究结果表明此类纳米材料的生态毒性效应不容忽视,为此应进一步加强其环境健康和生态毒性研究,为纳米材料的生态风险评价和安全评估提供科学依据,促进纳米技术的健康、安全和可持续发展。
With the mass production and widespread use of nanomaterials, the potential for their release into the environment is increasing. The potential risks and ecological effect to human health and ecological environment has become a new field of scientific research. In this study the impact of nano-ZnO and nano-TiO2 on aquatic ecosystems has been investigated using microalage Scenedesmus oblignus as a model. Microalgae S. oblignus were exposed to nano-ZnO and nano-TiO2 at different doses（0.01, 0.1, 0.5, 1, 5, 50 mg·L^-1 and 1, 5, 10, 50, 100, 200 mg·L^-1） for 96 h. Response of the growth, photosynthetic pigments and antioxidant enzyme activities were selected as assessment indicators. The results indicated that the effect of nano-ZnO within the concentrations of 0.01, 0.05, 1 mg·L^-1 on the growth of S. oblignus showed a significant improvement（P〈0.05） but no significant difference on protein content compared with control. However, when the concentration was increased to 5 mg·L^-1, nano-ZnO started to bring an evident stress to the growth and protein content, and high concentrations of 50 mg·L^-1 significantly inhibited the growth and protein content, while the inhibitation of photosynthetic pigments, and superoxide dismutase（SOD） and peroxidase（POD） activities was observed in lower concentrations. Similarly, dose-effects of nano-TiO2 was also observed in S. oblignus, being found to promote the growth at low concentrations of 1 mg·L^-1, which could increase the content of photosynthetic pigments, especially the content of the chlorophyll b and protein. As the concentration increased, the stimulative effect was reduced and the inhibition effect was enhanced. The influence on the activities of SOD and POD was consistent with that of cell growth. These studies suggested that nano-ZnO and nano-TiO2 at high concentrations induced toxicological effects.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2013年第6期1122-1127,共6页
Journal of Agro-Environment Science
基金
国家自然科学基金(21077052)
江苏省社会发展项目(BE2012737)
