RESUMEN
We aimed to: (1) evaluate the change in mutagenicity of a fenitrothion-containing solution during photolysis and (2) elucidate mutagenic compounds that were possible major contributors to mutagenicity. A batch test involving irradiation by natural sunlight was conducted on the solution, and then HPLC fractionation, mutagenicity testing, and gas chromatography-mass spectrometry (GC-MS) analysis were performed on the irradiated solution. During the 15-day photolysis, fenitrothion was almost completely decomposed, and 34 transformed products (TPs) were generated. Photolysis decreased the mutagenicity of the fenitrothion-containing solution for base-pair-substitution-detecting tester strains (YG1026 and YG1029) but increased mutagenicity for frameshift-detecting tester strains (YG1021 and YG1024). One TP was identified as a potential source of the increased mutagenicity; its molecular formula was estimated to be (CH(3)O)(2)PS-O-C(8)H(6)NO.
Asunto(s)
Fenitrotión/efectos de la radiación , Insecticidas/efectos de la radiación , Mutágenos/análisis , Mutágenos/toxicidad , Animales , Disparidad de Par Base , Biotransformación , Cromatografía Líquida de Alta Presión , Fenitrotión/metabolismo , Fenitrotión/toxicidad , Mutación del Sistema de Lectura , Cromatografía de Gases y Espectrometría de Masas , Técnicas In Vitro , Insecticidas/metabolismo , Insecticidas/toxicidad , Hígado/metabolismo , Pruebas de Mutagenicidad , Mutágenos/metabolismo , Fotólisis , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Fracciones Subcelulares/metabolismo , Luz SolarRESUMEN
The sonochemical photodegradation of fenitrothion, which is one of phosphorothiate insecticides, was carried out in the presence of Fe(III) and oxalate. The degradation rate was strongly influenced by initial concentrations of Fe(III) and oxalate. An initial fenitrothion concentration of 10 mg L(-1) was completely degraded after 30 min at pH 6 under the optimum conditions. Therefore, the photo-Fenton reaction combined with sonication in the presence of oxalate was available around neutral pH. The decrease of TOC as a result of mineralization of fenitrothion was observed during ultrasound (US)/ferrioxalate/UV process. In addition, the formations of nitrite and sulfate ions as end-products were observed during this degradation system. The decomposition of fenitrothion gave two kinds of intermediate products. The degradation mechanism of fenitrothion was proposed on the base of the evidence of the identified intermediates. Based on these results, US/ferrioxalate/UV system could be useful technology for the treatment of wastewater containing fenitrothion.
Asunto(s)
Fenitrotión/química , Fenitrotión/efectos de la radiación , Oxalatos/química , Oxalatos/efectos de la radiación , Sonicación/métodos , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiación , Purificación del Agua/métodos , Insecticidas/química , Insecticidas/efectos de la radiación , Dosis de Radiación , Rayos UltravioletaRESUMEN
Dichlorvos and fenitrothion residues found in spinach grown in greenhouse covered either by regular vinyl film or UV-absorbing vinyl film (UV-A) were analyzed by gas chromatography. After one day, dichlorvos residues in spinach covered with regular vinyl film and UV-A degraded by 97% and 80%, respectively, and degraded 100% after three days covered with regular vinyl film and six days covered with UV-A. After three days, fenitrothion residue in spinach covered with regular vinyl film degraded by 72% and then by 97% after six days; residue in spinach covered with UV-A degraded by 50% after three days and by 95% after six days. These results indicate that UV-A used to prevent the occurrence of insects and fungi in greenhouses reduced the degradation rates of dichlorvos and fenitrothion.