Marine plastic pollution represents a key environmental concern. Whilst ecotoxicological data for plastic is increasingly available, its impact upon marine phytoplankton remains unclear. Owing to their predicted abundance in the marine environment and likely interactions with phytoplankton, here we focus on the smaller fraction of plastic particles (~50 nm and ~2 µm polystyrene spheres). Exposure of natural phytoplankton communities and laboratory cultures revealed that plastic exposure does not follow traditional trends in ecotoxicological research, since large phytoplankton appear particularly susceptible towards plastics exposure despite their lower surface-to-volume ratios. Cell declines appear driven by hetero-aggregation and co-sedimentation of cells with plastic particles, recorded visually and demonstrated using confocal microscopy. As a consequence, plastic exposure also caused disruption to photosynthetic functioning, as determined by both photosynthetic efficiency and high throughput proteomics. Negative effects upon phytoplankton are recorded at concentrations orders of magnitude above those estimated in the environment. Hence, it is likely that impacts of NPs and MPs are exacerbated at the high concentrations typically used in ecotoxicological research (i.e., mg L^-1).

海洋塑料污染是一个关键的环境问题。虽然塑料的生态毒理学数据越来越多，但其对海洋浮游植物的影响仍不清楚。由于它们在海洋环境中的预测丰度以及可能与浮游植物的相互作用，在这里我们关注较小部分的塑料颗粒（~50 nm 和~2 µm 聚苯乙烯球）。天然浮游植物群落和实验室培养物的暴露表明，塑料暴露不遵循生态毒理学研究的传统趋势，因为尽管大型浮游植物的表面积与体积比较低，但它们似乎特别容易受到塑料暴露的影响。细胞衰退似乎是由细胞与塑料颗粒的异质聚集和共沉淀驱动的，目测记录并使用共聚焦显微镜进行证明。因此，塑料暴露也会对光合功能造成破坏，这取决于光合效率和高通量蛋白质组学。对浮游植物的负面影响的记录浓度比环境中估计的浓度高出几个数量级。因此，在生态毒理学研究中通常使用的高浓度下，NPs 和 MPs 的影响可能会加剧。即， mg L ^-1 )。