This paper deals with species sensitivity distributions (SSDs) for the lipophilic insecticide lufenuron and benthic arthropods based on sediment-spiked laboratory toxicity tests. This compound that inhibits chitin synthesis and moulting of arthropods persists in sediment. Using field-collected sediment, toxicity tests were conducted with three macro-crustaceans and six insects. The Hazardous Concentration to 5% of the tested species, the HC5 (and 95% confidence limit), derived from an SSD constructed with 10d-LC50′s was 2.2 (1.2–5.7) μg/g organic carbon (OC) in dry sediment. In addition, HC5 values derived from SSDs constructed with 28d-LC10 and 28-d LC50 values were 0.13 (0.02–1.50) μg/g OC and 2.0 (1.3–5.5) μg/g OC, respectively. In 28d toxicity tests with Chironomus riparius and Hyalella azteca, a higher sensitivity was observed when using lufenuron-spiked field-collected sediment than in lufenuron-spiked artificial sediment. Overall, the non-biting midge C. riparius appeared to be a representative and sensitive standard test species to assess effects of lufenuron exposure in sediment. The Tier-1 (based on standard test species), Tier-2 (based on standard and additional test species) and Tier-3 (model ecosystem approach) regulatory acceptable concentrations (RACs) for sediment-spiked lufenuron did not differ substantially. The Tier-2 RAC was the lowest. Since to our knowledge this study is the first in the open literature that evaluates the tiered approach in the sediment effect assessment procedure for pesticides, we advocate that similar evaluations should be conducted for pesticides that differ in toxic mode-of-action.

本文基于掺有沉淀物的实验室毒性试验，研究了亲脂性杀虫剂氟苯磺隆和底栖节肢动物的物种敏感性分布（SSD）。这种抑制甲壳质合成和节肢动物蜕皮的化合物在沉积物中持续存在。使用现场收集的沉积物，对三种大型甲壳类动物和六种昆虫进行了毒性测试。源自10d-LC50's固态硬盘的HC5（和95％置信限）的5％的有害物质浓度是在干燥沉积物中的2.2（1.2-5.7）μg/ g有机碳（OC） 。此外，从采用28d-LC10和28dLC50值构建的SSD得出的HC5值分别为0.13（0.02-1.50）μg/ g OC和2.0（1.3-5.5）μg/ g OC。在28天的毒性试验中，使用Chironomus riparius和Hyalella azteca，使用加倍加氟苯脲酮加标的田间沉积物时，观察到的灵敏度高于加加倍加氟苯脲酮加标的人工沉积物。总体而言，无咬mid蚊似乎是评估氟芬隆暴露在沉积物中的影响的代表性且敏感的标准测试物种。沉积物加标的氟苯磺隆的方法1（基于标准测试物种），方法2（基于标准和其他测试物种）和方法3（模型生态系统方法）监管可接受浓度（RAC）并无显着差异。Tier-2 RAC最低。由于据我们所知，该研究是公开文献中第一个评估农药沉积物效应评估程序中分层方法的研究，因此我们主张应对毒性作用方式不同的农药进行类似评估。