The widespread usage of ZnO nanoparticles (ZnO-NPs) and their potential to accumulate in sediment have raised great concerns regarding their chronic ecotoxicity in benthic ecosystems. This study investigated the effects of ZnO-NPs on the freshwater Asian clam Corbicula fluminea exposed to the nanoparticles through various routes in aquatic sediment environments. Significant amounts of Zn accumulated in the single-celled algae Chlorella ellipsoidea exposed to ZnO-NPs, resulting in foodborne exposure for C. fluminea. In addition, Zn was analyzed in overlaying water, pore water, and sediment in aquatic sediment environments and was found to accumulate mostly in sediment. Co-exposure to foodborne and waterborne ZnO-NPs significantly increased the mortality in C. fluminea compared to the mortality in clams exposed to untreated algae (about two-fold increase on day 28). Further evidence showed that bioaccumulation (about 1.5-fold increase), the expression of stress genes (about 1.5-fold increase), and DNA damage (about two-fold increase) were significantly enhanced in C. fluminea upon co-exposure to foodborne and waterborne ZnO-NPs compared with the levels in untreated algae on day 14. This study helps broaden the understanding of the ecotoxicity of ZnO-NPs and their interactions with sediment, algae, and bivalves in benthic ecosystems.

中文翻译：

---

共同暴露于水生沉积物环境中的食源性和水性ZnO纳米颗粒可增强淡水亚洲蛤Cor（Corbicula fluminea）中的DNA损伤和胁迫基因表达

ZnO纳米颗粒（ZnO-NPs）的广泛使用及其在沉积物中积累的潜力引起了人们对其在底栖生态系统中的长期生态毒性的极大关注。这项研究调查了ZnO-NPs对水生沉积物环境中通过各种途径暴露于纳米颗粒的淡水亚洲蛤Cor（Corbicula fluminea）的影响。暴露于ZnO-NPs的单细胞藻类小球藻中积累了大量的Zn ，导致通过食源性暴露于C. fluminea。此外，对水生沉积物环境中的覆盖水，孔隙水和沉积物中的锌进行了分析，发现锌主要在沉积物中积累。共同接触食源性和水源性ZnO-NPs会大大增加死亡率。与暴露于未经处理的藻类的蛤中的死亡率相比，C。fluminea（在第28天增加了约2倍）。进一步的证据表明，在共同暴露于食源性和非食源性流感嗜血杆菌时，生物累积（增加约1.5倍），胁迫基因的表达（增加约1.5倍）和DNA损伤（增加约2倍）显着增强。与第14天未经处理的藻类中的水平比较，该研究有助于拓宽对ZnO-NPs的生态毒性及其与底栖生态系统中沉积物，藻类和双壳类动物相互作用的了解。