Active pharmaceutical ingredients, such as levonorgestrel (LNG), continue to increase in aquatic ecosystems and are detected in environmental matrices; however, their ability to bioaccumulate and cause reproductive, developmental, and biochemical defects in benthic organisms, such as Macrocyclops albidus, is unknown. This study investigated the effects of LNG on the oxidative stress response, reproduction, and development of M. albidus. Levonorgestrel induced a significant (p<0.05) increase in total protein with increasing concentrations from 10 ng L^-1. Intracellular hydrogen peroxide levels were elevated after exposure to LNG (p<0.05). Malondialdehyde level declined as LNG concentration increased at day 7 and increased at higher LNG at day 14. Peroxidase activity was significantly (p<0.05) elevated by lower (1-100 ng L^-1) than higher (1000-10000 ng L^-1) concentrations of LNG. Glutathione S-transferase activity declined with increasing concentrations of LNG. Increased metamorphosis from the nauplii to the copepodite stage was significantly induced by 1000 and 10000 ng L^-1 LNG within four days of exposure. In addition, higher concentrations of LNG induced early production of egg sacs in female M. albidus within four days. Levonorgestrel bioaccumulated in M. albidus, with higher tissue concentrations occurring at high exposures. This study revealed that LNG is readily absorbed and causes stress by interfering with reproduction and metamorphosis in M. albidus, thereby highlighting the role of this zooplankton as a sensitive bioindicator of endocrine disruptors in aquatic ecosystems.

中文翻译：

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避孕活性成分左炔诺孕酮破坏了 Macrocyclops albidus 的生理机


左炔诺孕酮 （LNG） 等活性药物成分在水生生态系统中继续增加，并在环境基质中检测到;然而，它们在底栖生物（如 Macrocyclops albidus）中生物积累并导致生殖、发育和生化缺陷的能力尚不清楚。本研究调查了 LNG 对白枝杆菌氧化应激反应、繁殖和发育的影响。左炔诺孕酮诱导总蛋白显着 （p<0.05） 增加，浓度从 10 ng L ^-1 开始增加。暴露于 LNG 后细胞内过氧化氢水平升高 （p<0.05）。丙二醛水平随着 LNG 浓度在第 7 天的增加而下降，在第 14 天随着 LNG 浓度的增加而增加。过氧化物酶活性显着升高 （p<0.05） 低于较高 （1000-1000 ng ^-1 L） 浓度的 LNG 浓度 （1000-10000 ng L ^-1 ）。谷胱甘肽 S-转移酶活性随着 LNG 浓度的增加而下降。在暴露后 4 天内，1000 和 10000 ng L ^-1 LNG 显着诱导了从无节幼体到桡足阶段的增加。此外，较高浓度的 LNG 诱导雌性 M. albidus 在 4 天内提前产生卵囊。左炔诺孕酮在 M. albidus 中生物积累，在高暴露时组织浓度较高。这项研究表明，液化天然气很容易被吸收，并通过干扰白蚜的繁殖和来引起压力，从而突出了这种浮游动物作为水生生态系统中内分泌干扰物的敏感生物指标的作用。