【作者】 孟繁锰； 倪子淇； 谭丽菊； 王佳音； 陈燕珊； 张纳； 王江涛；

【Author】 Fanmeng Meng;Ziqi Ni;Liju Tan;Jiayin Wang;Yanshan Chen;Na Zhang;Jiangtao Wang;Ocean University of China ,Key Laboratory of Marine Chemistry Theory and Technology of the Ministry of Education;

【机构】 中国海洋大学海洋化学理论与技术教育部重点实验室；

【摘要】 通过测量96小时内的藻类密度和生长抑制率(IR)、叶绿素浓度和光合效率(Fv/Fm),研究了原始和老化聚苯乙烯(P-PS和A-PS)及其浸出液(L-PS)对中肋骨条藻的急性毒性影响。测量总蛋白(TP)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和丙二醛(MDA),以分析微塑料及其浸出物对微藻的氧化损伤。海水中微塑料的水动力直径、傅里叶红外和扫描电镜图像被用来研究聚苯乙烯(PS)在老化过程中的变化。结合电子显微镜分析了微藻细胞与微塑料的相互作用以及细胞的超微结构变化,全面系统地探究了微塑料对微藻的毒性机制。高浓度和小尺寸的PS对微藻的生长都有明显的抑制作用,而且随着暴露时间的增加,抑制作用更大。老化微塑料的抑制作用更为明显,推测是由老化PS本身和浸出液的协同作用造成的。浸出液对微塑料的负面作用是由于老化过程中一些添加剂的释放。在1.0μm,50mg/L A-PS处理组中,MDA的含量达到最高值54.41 nmol/mgprot,而且通过扫描电镜图像发现A-PS更容易与微藻细胞发生异质聚集。更多还原

【Abstract】 The acute toxic effects of pristine and aged polystyrene(P-PS and A-PS) and their leaching solutions(L-PS) on microalgae Skeletonema costatum were investigated by measuring algal density and growth inhibition rate(IR), chlorophyll concentration and photosynthetic efficiency(Fv/Fm) over 96 h. Total protein(TP), superoxide dismutase(SOD), catalase(CAT) and malondialdehyde(MDA) were measured to analyze the oxidative damage to microalgae by microplastics and their leachates. Hydrodynamic diameter of microplastics in seawater, FTIR and SEM images were used to study the changes of polystyrene during aging. The interaction of algae cell with microplastics and the cellular ultrastructure changes of cells were analyzed combined with electron microscopy for a comprehensive and systematic understanding on the mechanisms of microplastic toxicity to microalgae. Both high concentration and small size of PS had significant inhibitory effect on the growth of microalgae, and the inhibitory effect was greater with increasing exposure time. The inhibition effect of aged microplastics was more obvious, which was speculated to be caused by the synergistic effect of aged PS itself and leaching solution. The negative effect of leaching solution on microalgae was due to the release of some additives during the aging process. The content of MDA reached the highest value of 54.41 nmol/mgprot in 1.0 μm50 mg/L A-PS treatment group, and A-PS were found to be more prone to heterogeneous aggregation with algae cells by SEM.更多还原