gaiac - Research Institute for Ecosystem Analysis and Assessment, Kackertstrasse 10, 52072 Aachen, Germany.
Bayer AG, Alfred-Nobel-Straße 50, 40789 Monheim am Rhein, Germany.
Sci Total Environ. 2020 Jun 20;722:137673. doi: 10.1016/j.scitotenv.2020.137673. Epub 2020 Mar 5.
The aim of the environmental risk assessment of chemicals is the prevention of unacceptable adverse effects on the environment. Therefore, the risk assessment for in-soil organisms, such as earthworms, is based on two key elements: the exposure assessment and the effect assessment. In the current risk assessment scheme, these two elements are not linked. While for the exposure assessment, advanced exposure models can take the spatial and temporal scale of substances into account, the effect assessment in the lower tiers considers only a limited temporal and spatial variability. However, for soil organisms, such as earthworms, those scales play a significant role as species move through the soil in response to environmental factors. To overcome this gap, we propose a conceptual integration of pesticide exposure, ecology, and toxicological effects on earthworms using a modular modeling approach. An essential part of this modular approach is the environment module, which utilizes exposure models to provide spatially and temporally explicit information on environmental variables (e.g., temperature, moisture, organic matter content) and chemical concentrations. The behavior module uses this information and simulates the feeding and movement of different earthworm species using a trait-based approach. The resulting exposure can be processed by a toxicokinetic-toxicodynamic (TKTD) module. TKTD models are particularly suitable to make effect predictions for time-variable exposure situations as they include the processes of uptake, elimination, internal distribution, and biotransformation of chemicals and link the internal concentration to an effect at the organism level. The population module incorporates existing population models of different earthworm species. The modular approach is illustrated using a case study with an insecticide. Our results emphasize that using a modular model approach will facilitate the integration of exposure and effects and thus enhance the risk assessment of soil organisms.
化学品环境风险评估的目的是防止对环境产生不可接受的不利影响。因此，对土壤生物（如蚯蚓）的风险评估基于两个关键要素：暴露评估和效应评估。在当前的风险评估方案中，这两个要素没有联系。虽然对于暴露评估，先进的暴露模型可以考虑物质的时空尺度，但较低层次的效应评估只考虑有限的时空变异性。然而，对于土壤生物，如蚯蚓，这些尺度在物种响应环境因素在土壤中移动时起着重要作用。为了克服这一差距，我们提出了一种使用模块化建模方法整合农药暴露、生态学和对蚯蚓的毒理学效应的概念。这种模块化方法的一个重要部分是环境模块，它利用暴露模型提供有关环境变量（如温度、湿度、有机质含量）和化学浓度的时空显式信息。行为模块使用此信息并使用基于特征的方法模拟不同蚯蚓物种的摄食和移动。由此产生的暴露可以由毒代动力学-毒效动力学 (TKTD) 模块进行处理。TKTD 模型特别适合对时变暴露情况进行效应预测，因为它们包括化学物质的吸收、消除、内部分布和生物转化过程，并将内部浓度与生物体水平的效应联系起来。种群模块包含不同蚯蚓物种的现有种群模型。使用杀虫剂的案例研究说明了模块化方法。我们的结果强调，使用模块化模型方法将有助于暴露和效应的整合，从而增强对土壤生物的风险评估。
