Silver nanoparticles adversely affect the swimming behavior of European Whitefish (<i>Coregonus lavaretus</i>) larvae within the low µg/L range

The aim of this study was to determine the effects of silver nanoparticles (AgNPs; speciation: NM-300 K) in the lab on the behavior of larvae in European Whitefish (<i>Coregonus lavaretus</i>), a relevant model species for temperate aquatic environments during alternating light and darkness phases. The behavioral parameters measured included activity, turning rate, and distance moved. <i>C. lavaretus</i> were exposed to AgNP at nominal concentrations of 0, 5, 15, 45, 135, or 405 µg/L (n = 33, each) and behavior was recorded using a custom-built tracking system equipped with light sources that reliably simulate light and darkness. The observed behavior was analyzed using generalized linear mixed models, which enabled reliable detection of AgNP-related movement patterns at 10-fold higher sensitivity compared to recently reported standard toxicological studies. Exposure to 45 µg/L AgNPs significantly resulted in hyperactive response patterns for both activity and turning rates after an illumination change from light to darkness suggesting that exposure to this compound triggered escape mechanisms and disorientation-like behaviors in <i>C. lavaretus</i> fish larvae. Even at 5 µg/L AgNPs some behavioral effects were detected, but further tests are required to assess their ecological relevance. Further, the behavior of fish larvae exposed to 135 µg/L AgNPs was comparable to the control for all test parameters, suggesting a triphasic dose response pattern. Data demonstrated the potential of combining generalized linear mixed models with behavioral investigations to detect adverse effects on aquatic species that might be overlooked using standard toxicological tests.本研究旨在探究实验室条件下银纳米颗粒（silver nanoparticles, AgNPs；形态：NM-300 K）对欧洲白鲑（*Coregonus lavaretus*）幼虫行为的影响。欧洲白鲑是温带水生环境中的代表性模式物种，本实验在交替光照与黑暗的周期环境下开展。本次实验测量的行为参数包括活动度、转身速率与移动距离。研究人员以标称浓度分别为0、5、15、45、135及405 μg/L的AgNPs暴露*C. lavaretus*，每组样本量为33，并采用定制化追踪系统记录其行为，该系统配备可稳定模拟明暗环境的光源。本研究采用广义线性混合模型（generalized linear mixed models）对观测得到的行为数据进行分析，相较近期报道的标准毒理学研究，该方法可将AgNP相关运动模式的检测灵敏度提升10倍。实验结果显示，当光照从明切换至暗后，暴露于45 μg/L AgNPs的幼虫在活动度与转身速率上均显著表现出多动模式，表明该化合物暴露会触发*C. lavaretus*幼鱼的逃逸机制与类定向障碍行为。即使在5 μg/L的AgNPs暴露条件下，也观测到了部分行为效应，但仍需开展进一步实验以评估其生态相关性。此外，暴露于135 μg/L AgNPs的幼鱼行为与对照组无显著差异，提示存在三阶段剂量反应模式。本研究数据证实，将广义线性混合模型与行为学研究相结合，可有效检测出标准毒理学测试可能遗漏的水生物种不良效应。