Bioplastics such as polylactic acid are actually promoted as eco-friendly alternatives to fossil fuel-derived plastics, yet bioplastic toxicity remains poorly known. Here we studied the acute and multigenerational effects of polylactic acid microplastics on the copepod Eurytemora affinis, a bioindicator species of zooplankton. Results on acute toxicity revealed that lethal concentration values are higher for adult males, of 134.6 mg microplastic/L, than for adult females, of 106.9 mg/L. In multigeneration exposure, 400 µg/L polylactic acid microplastics induced higher mortality, production of smaller-sized eggs, elongation of the naupliar phase, and offspring with lower fitness. This led to reduction in female body size, including prosome length, width, and volume. Noteworthy, we also observed a recovery in copepod survival and reproductive parameters in the fifth filial generation.

聚乳酸等生物塑料实际上被宣传为化石燃料塑料的环保替代品，但生物塑料的毒性仍然鲜为人知。在这里，我们研究了聚乳酸微塑料对浮游动物生物指示物种桡足类Eurytemora affinis的急性和多代影响。急性毒性结果显示，成年男性的致死浓度为 134.6 毫克微塑料/升，高于成年女性的致死浓度为 106.9 毫克/升。在多代暴露中，400 µg/L 聚乳酸微塑料会导致更高的死亡率、产下较小尺寸的卵、延长无节幼体阶段以及降低后代的健康度。这导致女性身体尺寸减小，包括前体长度、宽度和体积。值得注意的是，我们还观察到第五代子代桡足类存活率和繁殖参数的恢复。