Boğaziçi University, Institute of Environmental Sciences, Bebek, 34342 Istanbul, Turkey.
European University of Lefke, Gemikonagi, Lefke, Cyprus.
Sci Total Environ. 2020 Nov 15;743:140479. doi: 10.1016/j.scitotenv.2020.140479. Epub 2020 Jun 24.
Microplastic pollution has become a global problem and it is threatening soil and water bodies around the world. In this study, i) the sole effect of 0.5 μm sized polystyrene microplastics under different concentrations (1, 5, 50, 100, and 1000 mg/L) and ii) the combined effect of the microplastic-metal combination (Cu, Zn, Mn) were investigated on the growth and chlorophyll a content of the freshwater microalgae; Chlorella vulgaris. Results showed that lower concentrations of microplastics (1, 5 mg/L) had no impact while higher concentrations (50, 100, 1000 mg/L) significantly reduced growth and chlorophyll a content of Chlorella vulgaris. Highest inhibition ratios were found between 15.71 and 28.86% on growth and 9.2-21.3% on chlorophyll a concentration for 50-1000 mg/L of microplastic. Microplastic-metal combinations showed greater inhibition on growth and chlorophyll a concentration. It has been shown that single metal-microplastic combinations reduced growth by 47.83-49.57% and chlorophyll a concentration by 44.75-50.25%. However, a much higher impact was observed for the triple metal-microplastic combination by 70.43% and 64.09% on growth and chlorophyll a content, respectively. SEM images provided insight into the probable cause of the toxic effect as the microplastic particles were adsorbed and embedded on the algal cell. Negative effects were observed generally at the early stages of exposure and weakened over time.
微塑料污染已成为全球性问题，正在威胁着世界各地的土壤和水体。在这项研究中，i）研究了不同浓度（1、5、50、100 和 1000mg/L）的 0.5μm 尺寸聚苯乙烯微塑料的单一效应，ii）研究了微塑料-金属组合（Cu、Zn、Mn）的联合效应对淡水微藻；小球藻的生长和叶绿素 a 含量的影响。结果表明，较低浓度的微塑料（1、5mg/L）没有影响，而较高浓度（50、100、1000mg/L）则显著降低了小球藻的生长和叶绿素 a 含量。在 50-1000mg/L 的微塑料浓度下，生长和叶绿素 a 浓度的最高抑制率分别为 15.71%和 28.86%。微塑料-金属组合对生长和叶绿素 a 浓度的抑制作用更大。研究表明，单一金属-微塑料组合使生长减少了 47.83%-49.57%，叶绿素 a 浓度减少了 44.75%-50.25%。然而，三重金属-微塑料组合的影响要大得多，生长和叶绿素 a 含量分别减少了 70.43%和 64.09%。扫描电子显微镜（SEM）图像提供了可能的毒性作用原因的见解，因为微塑料颗粒被吸附并嵌入到藻类细胞中。在暴露的早期阶段观察到了负面效应，随着时间的推移，这些效应逐渐减弱。
