纳米TiO2与重金属Cd对铜绿微囊藻生物效应的影响

为了更全面地评价纳米TiO2的生物效应,尤其是纳米TiO2与其他环境污染物的联合作用,以铜绿微囊藻为受试生物,探讨了不同浓度的纳米TiO2,以及纳米TiO2与Cd联合作用对藻生长的影响。根据叶绿素a及藻胆蛋白的含量变化,低浓度的纳米TiO2溶液(0～50mg.L-1)可以促进藻的生长,当纳米TiO2的浓度大于50mg·L-1时,藻细胞的生长有所抑制,生长减慢,并呈剂量-效应关系;当纳米TiO2与Cd离子同时存在时,由于纳米TiO2对Cd离子的吸附作用,水中游离态Cd离子浓度降低,Cd离子对藻的毒性明显降低。因此,纳米TiO2的生态毒性和环境效应不容忽视,同时,应重视纳米材料及与其他环境污染物质共同作用后的生物效应。

Ecological Effects of Nano-TiO2 and Heavy Metal Cd on M. aeruginosa

To evaluate the environmental safety of the joint action of nano-TiO₂ and metal Cd, M. aeruginosa was used as the model organism to investigate the effect of different concentrations of nano-TiO₂ and nano-TiO₂ with the heavy metal Cd on algae photosynthesis in the aquatic environment. Nano-TiO₂ can promote the growth of algae at low concentrations (0~50 mg·L^-1), while the algae cells growth rate was inhibited when the concentrations of nano-TiO₂ were greater than 50 mg·L^-1 in a pattern of dosage effect. As the presence of nano-TiO₂ and Cd ions, the toxicity of ions was reduced significantly because of the adsorption of Cd ions on nano-TiO₂ . Therefore, the ecological toxicity and environmental effects of nano-TiO₂ should not be neglected. The biological effects of nanomaterials combined with other environmental pollutants should be considered.