不同粒径微塑料对十溴二苯醚在斑马鱼体内富集和毒性效应的影响

Microplastics are well-know emerging contaminants and has raised global concerns over its wide distribution in the aquatic environment. It could modify the environmental behaviors and toxic effects of other pollutants by adsorption. However, the impact of microplastics with different particle sizes on other pollutants is still unclear. Our previous research found that polyethylene microplastics (PE-MPs) can adsorb decabromodiphenyl ether (BDE-209). In this project, zebrafish are exposed to PE-MPs with different particle sizes and BDE-209. The bioaccumulation and metabolism of the two toxicants in different tissues will be investigated after different exposure times. The thyroid endocrine disrupting toxicity after single and combined exposure will also be explored using RT-PCR, Western Blot, ELISA and Paraffin sectioning. The results help us understand the influences of PE-MPs with different particle sizes on BDE-209 in the environmental behaviors and toxic effects. This study can provide references for the ecological risk assessment of organic pollutants and microplastics, and also provide research method for the other widespread particulate pollutants and trace organic toxicants.

微塑料作为一种新型环境污染物，由于其在水体、沉积物和生物体内的广泛检出而备受关注。微塑料可以通过吸附作用影响其他污染物在生物体内的富集和毒性效应，然而，不同粒径微塑料对此影响尚不清楚。本项目以聚乙烯微塑料（PE-MPs）可以吸附十溴二苯醚（BDE-209）为研究基础，以斑马鱼为受试生物，通过不同粒径PE-MPs和BDE-209单独及复合暴露，定量分析暴露不同时间后，两者及代谢物在斑马鱼不同组织内的含量，解析不同粒径PE-MPs对BDE-209在斑马鱼体内富集和代谢的影响；采用RT-PCR、Western Blot、ELISA和石蜡切片等技术，分析单独及复合暴露后的甲状腺内分泌干扰毒性，揭示不同粒径PE-MPs对BDE-209生物毒性的影响及其与化学行为的相关性。本研究可为有机污染物与微塑料共存时的生态风险评价提供参考依据，并为其它颗粒物与污染物复合暴露提供研究思路。

微塑料作为一种新型环境污染物，由于其在各类环境介质中广泛检出而备受关注。微塑料除了自身危害外，还能改变其他污染物的化学行为和毒性效应。本项目以微塑料为研究对象，通过不同浓度、不同粒径和不同材质微塑料暴露小球藻，全面分析微塑料对水生微藻的危害。结果表明，各种微塑料均没有影响小球藻的增殖，与聚乙烯微塑料相比，同粒径同浓度的聚苯乙烯微塑料降低小球藻细胞内光合色素的含量和集群细胞比例；高浓度微塑料抑制小球藻的光合效率且降低胞内可溶性蛋白含量。在对微塑料和其他污染物复合暴露的研究中发现，投喂微塑料并没有改变重金属铅在鲤肝脏、肌肉和性腺等组织内的富集。在不同粒径微塑料与十溴二苯醚（BDE-209）水体长期复合暴露的研究中发现，微塑料粒径越小越易在斑马鱼肝脏内富集，且小粒径微塑料单独暴露或者与BDE-209复合暴露均显著降低斑马鱼血浆中雌二醇的含量，小粒径微塑料与BDE-209复合暴露降低斑马鱼血浆中睾酮含量，引起斑马鱼的生殖内分泌干扰效应。本研究可为环境中微塑料的生态风险评价提供参考依据，并为其它颗粒物与污染物复合暴露提供研究思路。