纳米TiO_2与重金属Cd对铜绿微囊藻生物效应的影响

Biological Effects of Nano-TiO_2 and Heavy Metal Cd on M.aeruginosa

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。

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.