Neonicotinoid insecticides pose risks that need to be managed for conservation of aquatic ecosystems. In this study, we evaluated the associations between the estimated environmental concentrations of two neonicotinoid insecticides (imidacloprid and dinotefuran) and the total abundances of seven functional feeding groups (FFGs) of benthic invertebrate communities in rivers in urban rice-paddy areas in four Japanese regions. Regional datasets of benthic invertebrate communities and environmental variables available for Japan were analyzed. The associations between neonicotinoid exposure and benthic functional groups in each region were evaluated by applying a partial redundancy analysis to each regional dataset. We then examined whether there was an interregionally consistent pattern in the observed associations to ascertain the general applicability of the associations. In two of the four regions, the associations of the total abundances of the seven FFGs with neonicotinoid concentrations were significant, suggesting negative effects of imidacloprid and dinotefuran on river ecosystem functions in these two Japanese regions. Moreover, although the associations in the remaining two regions were not significant, the pattern of associations of the total abundances of six of the FFGs (shredders, filter feeders, collectors, grazers, predators, and scavengers) with imidacloprid concentrations seemed to be consistent among the four regions. This implies broad-scale negative effects of imidacloprid on river ecosystem functions in urban rice-paddy areas. We did not, however, find any interregionally consistent patterns in the associations with dinotefuran concentrations. This may be related to the multicollinearity with the imidacloprid concentrations and/or the low maximum dinotefuran concentration relative to the toxicity values of this neonicotinoid. Therefore, the association between dinotefuran and river ecosystem functions requires additional investigation. We believe that this type of hypotheses-generating research using country-wide biomonitoring and exposure databases can be a great aid in future ecological risk assessment studies.

新烟碱类杀虫剂带来的风险需要加以管理，以保护水生生态系统。在这项研究中，我们评估了两种新烟碱类杀虫剂（吡虫啉和二甲呋喃）的估计环境浓度与日本四个城市稻田地区河流中底栖无脊椎动物群落的七个功能性摄食组（FFG）的总丰度之间的关联。 。分析了日本可利用的底栖无脊椎动物群落的区域数据集和环境变量。通过对每个区域数据集进行部分冗余分析，评估每个区域中新烟碱暴露与底栖功能组之间的关联。然后，我们检查了观察到的关联中是否存在区域间一致的模式，以确定关联的一般适用性。在四个地区中的两个地区，七个FFG的总丰度与新烟碱浓度之间的相关性很显着，这表明吡虫啉和二氯呋喃对这两个日本地区的河流生态系统功能具有负面影响。此外，尽管在其余两个区域中的关联并不显着，但六种FFG（切碎机，滤食器，收集器，放牧者，捕食者和清除剂）与吡虫啉浓度的总丰度之间的关联模式似乎是一致的四个地区。这意味着吡虫啉对城市稻田中河流生态系统功能的广泛负面影响。但是，我们未发现与二氯呋喃浓度有关的区域间一致模式。这可能与吡虫啉浓度的多重共线性和/或相对于该新烟碱类药物的毒性值而言较低的最大二替呋喃浓度低有关。因此，双替呋喃与河流生态系统功能之间的联系需要进一步调查。我们认为，使用全国范围的生物监测和暴露数据库进行的这类假设生成研究可以为未来的生态风险评估研究提供巨大帮助。这可能与吡虫啉浓度的多重共线性和/或相对于该新烟碱类药物的毒性值而言较低的最大二呋喃浓度较低有关。因此，双替呋喃与河流生态系统功能之间的联系需要进一步调查。我们认为，使用全国范围的生物监测和暴露数据库进行的这类假设生成研究可以为未来的生态风险评估研究提供巨大帮助。这可能与吡虫啉浓度的多重共线性和/或相对于该新烟碱类药物的毒性值而言较低的最大二呋喃浓度较低有关。因此，双替呋喃与河流生态系统功能之间的联系需要进一步调查。我们认为，使用全国范围的生物监测和暴露数据库进行的这类假设生成研究可以为未来的生态风险评估研究提供巨大帮助。