Department of Biological and Environmental Science, University of Jyväskylä, Jyväskylä 40014, Finland.
Department of Fish Ecology and Evolution, Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Kastanienbaum 6047, Switzerland.
Ecotoxicol Environ Saf. 2024 Oct 15;285:117017. doi: 10.1016/j.ecoenv.2024.117017. Epub 2024 Sep 20.
Anthropogenic chemical pollutants, such as fungicides, pose significant threats to natural ecosystems. Although the direct impacts of numerous chemicals are well-documented in simple environmental contexts, their indirect impacts are poorly understood. This study used two individual level laboratory experiments to assess direct and indirect effects of fungicides on the isopod Asellus aquaticus, a keystone detritivore in freshwater systems. First, a range-finding assay on three widely used fungicides (Fluazinam, Tebuconazole, Urea) showed that Tebuconazole had the strongest concentration-dependent negative effects on A. aquaticus growth and food consumption. Second, a factorial experiment using Tebuconazole assessed its direct and diet-mediated effects and showed that Tebuconazole reduced growth, feeding, and pigmentation through both pathways. The results indicate that assessing only direct impacts of toxic chemicals could overlook critical interactions that are relevant in natural systems, such as those associated with diet. Our study highlights the importance of considering both direct and indirect effects in environmental toxicology to better understand the full impacts of chemical pollutants in nature.
人为化学污染物，如杀菌剂，对自然生态系统构成重大威胁。尽管在简单的环境背景下，大量化学物质的直接影响已有充分记录，但它们的间接影响仍知之甚少。本研究使用两项个体水平的实验室实验，评估了杀菌剂对淡水系统中关键碎屑食性动物水生等足类（Asellus aquaticus）的直接和间接影响。首先，对三种广泛使用的杀菌剂（氟啶胺、戊唑醇、尿素）进行了范围发现测定，结果表明戊唑醇对水生等足类的生长和食物消耗具有最强的浓度依赖性负效应。其次，使用戊唑醇进行的析因实验评估了其直接和饮食介导的效应，结果表明戊唑醇通过两种途径降低了生长、摄食和色素沉着。研究结果表明，仅评估有毒化学物质的直接影响可能会忽略与自然系统相关的关键相互作用，例如与饮食相关的相互作用。本研究强调了在环境毒理学中考虑直接和间接效应的重要性，以更好地理解化学污染物在自然界中的全部影响。
