Plastics of different sizes (micro- and nano-sized) are often identified in aquatic environments. Nevertheless, their influence on marine organisms has not been widely investigated. In this study, the responses of the microalga Chlorella vulgaris to micro- and nanoplastics exposure were examined using long term toxicity test. The plastics tested were carboxyl-functionalized and non-functionalized polystyrene of 20, 50 and 500 nm in diameter. A reduction in algal cell viability and chlorophyll a concentration has been observed after exposure to the small sizes (20 and 50 nm) of plastics. Lactate dehydrogenase activity and reactive oxygen species concentration/production were significantly higher after exposure to the 20 nm nanoplastics than that of control confirming the stress condition. Fourier transform infrared (FTIR) spectroscopy analysis proved the attachment of nanoplastics to microalgae and rearrangement of extracellular polymeric substances. The cellular stress appeared as increased cell size, deformed cell wall and increased volume of starch grains.

通常在水生环境中识别出不同尺寸（微米和纳米尺寸）的塑料。然而，它们对海洋生物的影响尚未得到广泛研究。在这项研究中，使用长期毒性试验检查了微藻小球藻对微塑料和纳米塑料暴露的响应。测试的塑料是直径为20、50和500 nm的羧基官能化和非官能化聚苯乙烯。藻类细胞活力和叶绿素a的降低在暴露于小尺寸（20和50 nm）的塑料后，已观察到浓度升高。暴露于20 nm纳米塑料后，乳酸脱氢酶活性和活性氧浓度/产量显着高于对照，证实了应激条件。傅里叶变换红外（FTIR）光谱分析证明了纳米塑料对微藻的附着和细胞外聚合物的重排。细胞应激表现为细胞大小增加，细胞壁变形和淀粉粒体积增加。