Open AccessNano-sized Al2O3 reduces acute toxic effects of thiacloprid on the non-biting midge Chironomus riparius
Author(s) -
Carla S. Lorenz,
Anna-J. Wicht,
Leyla Guluzada,
Leilei Luo,
Leonie Jäger,
Barbara Crone,
Uwe Kärst,
Rita Triebskorn,
Yucang Liang,
Reiner Anwander,
Stefan B. Haderlein,
Carolin Hühn,
HeinzR. Köhler
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0176356
Subject(s) - thiacloprid , chironomus riparius , toxicology , toxicity , pesticide , larva , chemistry , biology , environmental chemistry , midge , imidacloprid , ecology , thiamethoxam , organic chemistry
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-Al 2 O 3 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-Al 2 O 3 (300 and 1000 mg/L), either solely or in binary mixtures. While thiacloprid resulted in elevated mortality, nano-Al 2 O 3 solely did not exert any effects. Moreover, we observed an aggregation of nano-Al 2 O 3 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-Al 2 O 3 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-Al 2 O 3, we assume that nano-Al 2 O 3 leads to a delay of mortality and does not entirely prevent it. As sorption measurements on pristine or defecated nano-Al 2 O 3 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.