The influence of microplastics (MPs) on transgenerational effects of pharmaceuticals are drawing growing attention, however, whether aged process will alter the carrier effects of MPs were unknown. In this study, the intergenerational toxicity of single and combined exposure of polystyrene microplastics (PS-MPs) and roxithromycin (ROX) were investigated at the environmentally related concentrations, using Daphina magna as test organism. In the presence of UV-aged PS-MPs, the survival of D. magna for maternal generation (F0) at ROX concentration of 0.1 and 10 µg/L were increased by 20% and 40%, respectively. Meanwhile, the inhibition effects of ROX on the number of offspring and intrinsic rate of natural increase were obviously moderated. All these reproductive toxicity of ROX and PS-MPs in the first offspring (F1) were further aggravated both for the single and combined exposure. And the adverse effects disappeared much easier for the single exposure compared to the co-exposure through subsequent recovery. The combined exposure resulted in the change of inhibition of ROX on the swimming velocity and acceleration of D. magna into induction, while the feeding behavior kept inhibited. The AChE activity was distinctly increased by 1.61-3.25 times for the single and combined treatments, and the induction level of UV-aged MPs was higher than that of original MPs. Oxidative stress of the single exposure of ROX and original PS-MPs was observed with obvious induction of T-AOC and SOD activity, while the significant increase of MDA content was observed for the co-exposure. Among all indicators, the biochemical biomarkers and time of first brood were attributed to a class among all indicators, indicating that the time of first brood might be the most sensitive reproductive toxicity index. These results illustrated that both maternal impacts and offspring quality need to be considered for assessment of interaction of emerging contaminants.

微塑料（MPs）对药物跨代效应的影响越来越受到关注，但老化过程是否会改变MPs的载体效应尚不清楚。在这项研究中，以大蚤作为试验生物，在环境相关浓度下研究了聚苯乙烯微塑料 (PS-MPs) 和罗红霉素 (ROX) 单次和联合暴露的代际毒性。在紫外线老化的 PS-MP 存在下，在 ROX 浓度为 0.1 和 10 µg/L 的情况下， D. magna母代 (F0) 的存活率分别增加了 20% 和 40%。同时，ROX对后代数量和内在自然增长率的抑制作用明显减弱。ROX 和 PS-MP 在第一个后代 (F1) 中的所有这些生殖毒性在单次和联合暴露下都进一步加重。与通过后续恢复的共同暴露相比，单次暴露的不利影响更容易消失。联合暴露导致 ROX 对D. magna游泳速度和加速度的抑制发生变化进入诱导状态，而摄食行为一直受到抑制。单处理和联合处理的AChE活性均显着提高1.61~3.25倍，UV老化MPs的诱导水平高于原始MPs。ROX和原PS-MPs单次暴露氧化应激后，T-AOC和SOD活性明显诱导，而同时暴露时MDA含量显着增加。在所有指标中，生化生物标志物和初育时间属于所有指标中的一类，表明初育时间可能是最敏感的生殖毒性指标。这些结果表明，在评估新兴污染物的相互作用时，需要考虑母体影响和后代质量。