Abstract：
The toxicity of neonicotinoids and many of their replacement insecticides to nontarget soil invertebrates such as earthworms has previously been established. However, the long-term effects of these substances on these organisms are largely unknown. In the field of soil ecotoxicology, lumbricid earthworms such as Eisenia andrei are used extensively due to the availability of standardized test methods and their adaptability to laboratory culture and testing. Multigenerational studies have gained popularity and attention in recent years, with a shift toward the use of long-term assays and lower concentrations of test chemicals. The use of exposure concentrations that include those measured in a monitoring program carried out by the Government of Ontario presents a realistic exposure scenario that may not show significant effects in contemporary, shorter term studies. We used current standardized test methods as a basis for the development of multigenerational studies on E. andrei. The effects of exposure to a single application of the insecticides thiamethoxam and cyantraniliprole on the survival and reproduction of E. andrei were observed over three (thiamethoxam) or two (cyantraniliprole) generations using consecutive reproduction tests. No significant impacts on adult survival were reported in any generation for either insecticide, whereas reproduction decreased between the first and second generations in the thiamethoxam test, with median effective concentration (EC50) values of 0.022 mg/kg dry weight reported for the first generation compared with 0.002 mg/kg dry weight in the second generation. For cyantraniliprole, an EC50 of 0.064 was determined for the first generation compared with 0.016 mg/kg dry weight in the second generation. A third generation was completed for the thiamethoxam test, and a significant decrease in reproduction was observed in all treatments and controls compared with previous generations. No significant difference between thiamethoxam treatments and the control treatment was reported for the third generation. Collectively, these data indicate that exposure of oligochaetes to these two insecticides at concentrations representative of field conditions may result in long-term stresses. Environ Toxicol Chem 2024;00:1-13. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
摘要：
先前已经确定了新烟碱类及其许多替代杀虫剂对非目标土壤无脊椎动物如蚯蚓的毒性。然而,这些物质对这些生物的长期影响在很大程度上是未知的。在土壤生态毒理学领域，由于标准化测试方法的可用性及其对实验室培养和测试的适应性，广泛使用了诸如Eiseniaandrei之类的lumbricid。近年来，多代研究受到了广泛的欢迎和关注，随着转向使用长期测定和较低浓度的测试化学品。使用暴露浓度，包括在安大略省政府实施的监测计划中测量的那些，提出了一个现实的暴露情景，在当代，短期研究。我们使用当前的标准化测试方法作为对E.andrei进行多代研究的基础。使用连续的繁殖测试，在三代（噻虫嗪）或两代（氰虫草）中观察到了暴露于单次施用杀虫剂噻虫嗪和氰虫草对E.andrei的存活和繁殖的影响。在任何一代杀虫剂中，均未报告对成年人的生存产生重大影响，而在噻虫嗪试验中，第一代和第二代之间的繁殖减少，第一代的中位有效浓度（EC50）值为0.022mg/kg干重，第二代为0.002mg/kg干重。对于cyantraniliprole，与第二代的0.016mg/kg干重相比，第一代的EC50为0.064。完成了第三代噻虫嗪测试，与前几代相比，在所有处理和对照中观察到繁殖显着减少。对于第三代，噻虫嗪治疗与对照治疗之间没有显着差异。总的来说，这些数据表明，在代表田间条件的浓度下，低聚类动物暴露于这两种杀虫剂可能会导致长期胁迫。环境毒物化学2024；00：1-13。©2024作者（S）。WileyPeriodicalsLLC代表SETAC出版的环境毒理学和化学。
