Abstract：
Microplastics (MPs) raise concerns not only as pollutants themselves, but also due to their ability to act as vectors of pollutants adsorbed from seawater, transferring them to marine organisms. However, the relevance of MPs as carriers of pollutants compared to microalgae needs further exploration. This study compared the role of MPs (2-10 μm non-oxidized and 10-15 μm oxidized high-density polyethylene) and natural organic particles (Rhodomonas lens microalgae, MA) as carriers of mercury (Hg, 2.3 μg Hg/L) and chlorpyrifos (CPF, 1.0 μg CPF/L) to adult Acartia tonsa copepods, after 24-48 h exposure. Dose-response experiments were first performed with adult female copepods exposed to oxidized MPs (0.25-4.0 mg/L), waterborne Hg (0.01-10.0 μg/L) and Ox MPs + Hg (0.25-4.0 mg oxidized MPs/L + 0.50-8.0 μg Hg/L) for 48 h, to complement previous studies that focused on the pesticide CPF. Effects were evaluated with four replicates for physiological and reproductive responses (6 females/replicate), biochemical techniques (40 individuals/replicate) and Hg/CPF bioaccumulation measurements (1000 individuals/replicate). Copepods accumulated Hg/CPF similarly from dissolved pollutants (6204 ± 2265 ng Hg/g and 1251 ± 646 ng CPF/g) and loaded MPs (3125 ± 1389 ng Hg/g and 1156 ± 266 ng CPF/g), but significantly less from loaded MA (21 ± 8 ng Hg/g and 173 ± 80 ng CPF/g). After 24-48 h, copepods exposed to MPs + Hg/CPF showed generally greater biological effects than those exposed to dissolved Hg/CPF or to MA + Hg/CPF, although differences were not statistically significant. MA + CPF had significantly lower AChE inhibition (1073.4 nmol min-1 mg-1) and MA + Hg lower GRx induction (48.8 nmol min-1 mg-1) compared to MPs + Hg/CPF and dissolved Hg/CPF (182.8-236.4 nmol min-1 mg-1 of AChE and 74.1-101.7 nmol min-1 mg-1 of GRx). Principal component analysis suggested different modes of action for Hg and CPF.
摘要：
微塑料(MP)不仅作为污染物本身引起了人们的关注，而且由于它们能够充当从海水中吸附的污染物的载体，将它们转移到海洋生物中。然而,与微藻相比，MP作为污染物载体的相关性需要进一步探索。本研究比较了MPs（2-10μm非氧化和10-15μm氧化高密度聚乙烯）和天然有机颗粒（红藻晶状体微藻，MA)作为汞(Hg，2.3μgHg/L)和毒死蜱(CPF，1.0μgCPF/L）对成年无牙足类动物，暴露后24-48小时（h）。剂量反应实验首先用暴露于氧化的MPs（0.25-4.0mg/L）的成年雌性co足动物进行，水性Hg（0.01-10.0μg/L）和OxMPsHg（0.25-4.0mg氧化MPs/L0.50-8.0μgHg/L）持续48小时，以补充以往关于农药公积金的研究。用四个重复的生理和生殖反应（6个雌性/重复）评估效果，生化技术（40个个体/重复）和Hg/CPF生物累积测量（1000个个体/重复）。co足类从溶解的污染物（6204±2265ngHg/g和1251±646ngCPF/g）中积累了汞/CPF，并负载了MPs（3125±1389ngHg/g和1156±266ngCPF/g），但明显低于负载的MA（21±8ngHg/g和173±80ngCPF/g）。24-48小时后，与暴露于溶解的Hg/CPF或MAHg/CPF的co足类相比，暴露于MPHg/CPF的co足类显示出更大的生物学效应，尽管差异无统计学意义。与MPsHg/CPF和溶解的Hg/CPF（182.8-236.4nmolmin-1mg-1）相比，MACPF的AChE抑制作用显着降低（1073.4nmolmin-1mg-1），MAHg的GRx诱导降低（48.8nmolmin-1mg-1）。主成分分析表明Hg和CPF的作用方式不同。
