Research article - Peer-reviewed, 2020
Reduction of Pesticide Toxicity Under Field-Relevant Conditions? The Interaction of Titanium Dioxide Nanoparticles, Ultraviolet, and Natural Organic Matter
Luederwald, Simon; Meyer, Frederik; Gerstle, Verena; Friedrichs, Lisa; Rolfing, Katrin; Schreiner, Verena C.; Bakanov, Nikita; Schulz, Ralf; Bundschuh, MircoAbstract
In surface waters, the illumination of photoactive engineered nanomaterials (ENMs) with ultraviolet (UV) light triggers the formation of reactive intermediates, consequently altering the ecotoxicological potential of co-occurring organic micropollutants including pesticides due to catalytic degradation. Simultaneously, omnipresent natural organic matter (NOM) adsorbs onto ENM surfaces, altering the ENM surface properties. Also, NOM absorbs light, reducing the photo(cata)lytic transformation of pesticides. Interactions between these environmental factors impact 1) directly the ecotoxicity of photoactive ENMs, and 2) indirectly the degradation of pesticides. We assessed the impact of field-relevant UV radiation (up to 2.6 W UVA/m(2)), NOM (4 mg TOC/L), and photoactive ENM (nTiO(2), 50 mu g/L) on the acute toxicity of 6 pesticides inDaphnia magna. We selected azoxystrobin, dimethoate, malathion, parathion, permethrin, and pirimicarb because of their varying photo- and hydrolytic stabilities. Increasing UVA alone partially reduced pesticide toxicity, seemingly due to enhanced degradation. Even at 50 mu g/L, nano-sized titanium dioxide (nTiO(2)) reduced but also increased pesticide toxicity (depending on the applied pesticide), which is attributable to 1) more efficient degradation and potentially 2) photocatalytically induced formation of toxic by-products. Natural organic matter 1) partially reduced pesticide toxicity, not evidently accompanied by enhanced pesticide degradation, but also 2) inhibited pesticide degradation, effectively increasing the pesticide toxicity. Predicting the ecotoxicological potential of pesticides based on their interaction with UV light or interaction with NOM was hardly possible, which was even more difficult in the presence of nTiO(2). (c) 2020 The Authors.Environmental Toxicology and Chemistrypublished by Wiley Periodicals LLC on behalf of SETAC.Keywords
Photolysis; Photocatalysis; Titanium dioxide; Pesticide; UV radiation; Natural organic matterPublished in
Environmental Toxicology and Chemistry2020, volume: 39, number: 11, pages: 2237-2246
Publisher: WILEY
Authors' information
Luederwald, Simon
University of Koblenz and Landau
Meyer, Frederik
University of Koblenz and Landau
Gerstle, Verena
University of Koblenz and Landau
Friedrichs, Lisa
University of Koblenz and Landau
Rolfing, Katrin
University of Koblenz and Landau
Schreiner, Verena C.
University of Koblenz and Landau
Bakanov, Nikita
University of Koblenz and Landau
Schulz, Ralf
University of Koblenz and Landau
University of Koblenz-Landau
Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment
UKÄ Subject classification
Environmental Sciences
Publication Identifiers
DOI: https://doi.org/10.1002/etc.4851
URI (permanent link to this page)
https://res.slu.se/id/publ/108133