Photo-induced transformation of hexaconazole and dimethomorph over TiO2 suspension
| Autor: | Ezio Pelizzetti, Cristina Massolino, Paola Calza |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Chromatography
Aqueous solution Hydroquinone General Chemical Engineering Luminescent bacteria General Physics and Astronomy General Chemistry Acute toxicity Photocatalysis TiO2 Fungicides Hexaconazole Dimethomorph Morpholine Cyanuric acid chemistry.chemical_compound chemistry Toxicity Hexaconazole Cyanuric acid EC50 |
| Zdroj: | Journal of Photochemistry and Photobiology A: Chemistry. 200:356-363 |
| ISSN: | 1010-6030 |
| DOI: | 10.1016/j.jphotochem.2008.08.018 |
| Popis: | The photo-induced transformation in aqueous solution of hexaconazole and dimethomorph over irradiated titanium dioxide was studied. The investigation involved monitoring pesticides decomposition, identifying intermediate compounds, assessing mineralization, and evaluating toxicity of pesticides derivatives. HPLC/UV and HPLC/MS were used to follow the disappearance of the initial pesticides and the formation of intermediate products, while the acute toxicity was evaluated by using the Vibrio fischeri luminescent bacteria assay. Hexaconazole photocatalytic transformation proceeds through the formation of highly persistent compounds. The formation of cyanuric acid, a non-toxic compound refractory to photocatalytic treatment, was recognized. Conversely, the toxicity assays prove that neither hexaconazole nor its intermediates exhibit acute toxicity. Dimethomorph under photocatalytic treatment is completely mineralized within 14 h of irradiation. However, its transformation proceeds through the formation of toxic intermediates. A correlation exists between the evolution of the intermediate compounds and the toxicity profile, as the highest toxicity is measured when the intermediates with lower EC50 (hydroquinone and 4-chlorophenol) are formed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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