Lorenz Carla S, Wicht Anna-J, Guluzada Leyla, Luo Leilei, Jäger Leonie, Crone Barbara, Karst Uwe, Triebskorn Rita, Liang Yucang, Anwander Reiner, Haderlein Stefan B, Huhn Carolin, Köhler Heinz-R
Institute of Evolution and Ecology, Animal Physiological Ecology, University of Tübingen, Tübingen, Germany.
Institute of Physical and Theoretical Chemistry, University of Tübingen, Tübingen, Germany.
PLoS One. 2017 May 2;12(5):e0176356. doi: 10.1371/journal.pone.0176356. eCollection 2017.
This study focuses on interactions between nanoparticles and a pesticide. The aim was to investigate how nano-sized aluminum oxide (410 nm) can alter the toxic effects of thiacloprid, even if no sorption between particles and the insecticide takes place. Thus, our study investigated a rather unexplored interaction. We conducted our research with larvae of Chironomus riparius and used thiacloprid as test substance as its toxicity to C. riparius is well described. The used nano-Al2O3 particles where chosen due to their suitable properties. For testing the acute effects of the interaction, we exposed larvae to thiacloprid (0.5, 1.0, 2.0, and 5.0 μg/L) and nano-Al2O3 (300 and 1000 mg/L), either solely or in binary mixtures. While thiacloprid resulted in elevated mortality, nano-Al2O3 solely did not exert any effects. Moreover, we observed an aggregation of nano-Al2O3 within the lumen of the intestinal tract of the larvae. Further results showed a significantly reduced mortality of fourth instar larvae when they were exposed to mixtures of nanoparticles and the pesticide, compared to thiacloprid alone. With increasing nano-Al2O3 concentration, this effect became gradually stronger. Additionally, chemical analyses of internal thiacloprid concentrations implicate reduced uptake of thiacloprid in animals exposed to mixtures. However, as larvae exposed to thiacloprid concentrations > 0.5 μg/L showed severe convulsions, independent of the presence or concentration of nano-Al2O3, we assume that nano-Al2O3 leads to a delay of mortality and does not entirely prevent it. As sorption measurements on pristine or defecated nano-Al2O3 did not reveal any sorptive interaction with thiacloprid, we can exclude sorption-based reduction of thiacloprid bioavailability as a mechanism behind our results. Even though we used test substances which might not co-occur in the environment in the tested concentrations, our study gives evidence for an interaction besides adsorption, which is important to generally understand how nanoparticles might affect biota.
本研究聚焦于纳米颗粒与一种杀虫剂之间的相互作用。目的是探究纳米级氧化铝（410纳米）如何改变噻虫啉的毒性影响，即便颗粒与杀虫剂之间不存在吸附作用。因此，我们的研究调查了一种尚未充分探索的相互作用。我们以摇蚊幼虫开展研究，并使用噻虫啉作为测试物质，因为其对摇蚊幼虫的毒性已有详尽描述。所使用的纳米Al2O3颗粒因其合适的特性而被选用。为测试这种相互作用的急性影响，我们将幼虫单独或同时暴露于噻虫啉（0.5、1.0、2.0和5.0微克/升）以及纳米Al2O3（300和1000毫克/升）的二元混合物中。虽然噻虫啉导致死亡率升高，但单独的纳米Al2O3并未产生任何影响。此外，我们观察到纳米Al2O3在幼虫肠道腔内发生聚集。进一步结果表明，与单独暴露于噻虫啉相比，当四龄幼虫暴露于纳米颗粒与杀虫剂的混合物时，死亡率显著降低。随着纳米Al2O3浓度增加，这种影响逐渐增强。此外，对体内噻虫啉浓度的化学分析表明，暴露于混合物中的动物对噻虫啉的摄取减少。然而，由于暴露于噻虫啉浓度>0.5微克/升的幼虫出现严重抽搐，与纳米Al2O3的存在或浓度无关，我们推测纳米Al2O3导致死亡延迟，但并未完全阻止死亡。由于对原始或排出的纳米Al2O3的吸附测量未显示与噻虫啉有任何吸附相互作用，我们可以排除基于吸附的噻虫啉生物利用度降低作为我们结果背后的机制。尽管我们使用的测试物质在测试浓度下可能不会在环境中同时出现，但我们的研究为除吸附之外的相互作用提供了证据，这对于总体理解纳米颗粒如何影响生物群很重要。
