Institute for Environmental Sciences, University of Koblenz-Landau, Fortstrasse 7, 76829 Landau in der Pfalz, Germany.
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Lennart Hjelms väg 9, SWE-75007 Uppsala, Sweden.
Environ Sci Technol. 2022 May 3;56(9):5478-5488. doi: 10.1021/acs.est.1c08079. Epub 2022 Apr 20.
Emerging aquatic insects have the potential to retain aquatic contaminants after metamorphosis, potentially transporting them into adjacent terrestrial food webs. It is unknown whether this transfer is also relevant for current-use pesticides. We exposed larvae of the nonbiting midge, , to a sublethal pulse of a mixture of nine moderately polar fungicides and herbicides (log 2.5-4.7) at three field relevant treatment levels (1.2-2.5, 17.5-35.0, or 50.0-100.0 μg/L). We then assessed the pesticide bioaccumulation and bioamplification over the full aquatic-terrestrial life cycle of both sexes including the egg laying of adult females. By applying sensitive LC-MS/MS analysis to small sample volumes (∼5 mg, dry weight), we detected all pesticides in larvae from all treatment levels (2.8-1019 ng/g), five of the pesticides in the adults from the lowest treatment level and eight in the higher treatment levels (1.5-3615 ng/g). Retention of the pesticides through metamorphosis was not predictable based solely on pesticide lipophilicity. Sex-specific differences in adult insect pesticide concentrations were significant for five of the pesticides, with greater concentrations in females for four of them. Over the duration of the adults' lifespan, pesticide concentrations generally decreased in females while persisting in males. Our results suggest that a low to moderate daily dietary exposure to these pesticides may be possible for tree swallow nestlings and insectivorous bats.
新兴水生昆虫在变态后有可能保留水生污染物，从而将其转移到相邻的陆地食物网中。目前尚不清楚这种转移是否也与当前使用的农药有关。我们将非吸血蠓的幼虫暴露于九种中等极性杀菌剂和除草剂混合物的亚致死脉冲中（log 2.5-4.7），在三个田间相关处理水平（1.2-2.5、17.5-35.0 或 50.0-100.0μg/L）下进行处理。然后，我们评估了整个水生-陆地生命周期中两性的农药生物累积和生物放大作用，包括成年雌性的产卵。通过对小样本量（约 5 毫克，干重）应用灵敏的 LC-MS/MS 分析，我们在来自所有处理水平的幼虫中检测到了所有农药（2.8-1019ng/g），在最低处理水平的成虫中检测到了其中五种，在较高处理水平中检测到了八种（1.5-3615ng/g）。仅根据农药的亲脂性，无法预测农药在变态过程中的保留情况。五种农药在成虫中的性别特异性浓度差异显著，其中四种农药在雌性中的浓度更高。在成虫寿命期间，农药浓度通常在雌性中降低，而在雄性中持续存在。我们的研究结果表明，树燕雏鸟和食虫蝙蝠可能会有低至中等程度的每日膳食暴露于这些农药。
