The aim of this study was to investigate, analyze, and compare applied techniques suitable for achieving efficient removal of organophosphorus pesticides (OPPs) (malathion and fenitrothion) from aqueous solutions and analyze the degradation products and processes. Pesticide degradation efficiency (%) was monitored by high-performance liquid chromatography (HPLC) equipped with a photodiode array detector (DAD), while mineralization degree was determined by total organic carbon analysis (TOC). Daphnia magna was used for screening the environmental safety aspects of the degradation methods, i.e., for assessing the toxicity of solutions obtained after degradation. Additionally, a surface river water was utilized to examine the likely influence of organic matter on the pesticides’ degradation. Pesticide degradation products were identified using gas chromatography with a triple quadrupole mass detector (GC-MS/MS) as well as ultrahigh-performance liquid chromatography coupled with a linear ion trap, Orbitrap mass spectrometer (UHPLC-LTQ Orbitrap MS), and a simple pesticide degradation mechanism is proposed. Removal of pesticides from water using chlorine dioxide was successful, resulting in high degradation efficiency (98% for malathion and 81% for fenitrothion). Partial mineralization was achieved, and Daphnia magna mortality decreased in the waters containing degradation products (compared with the parent pesticides), indicating that the solutions formed were less toxic than the parent pesticides. Lower degradation rates (80% for malathion and 72% for fenitrothion) in Sava River water were measured, indicating the influence of the organic matter contained in this naturally occurring surface water. The results prove that chlorine dioxide could be used as an agent for successful removal of these OPPs from water.

中文翻译：

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马拉硫磷和杀nitro硫磷的降解产物，矿化作用和毒性评估

这项研究的目的是调查，分析和比较适用于实现从水溶液中有效去除有机磷农药（马拉硫磷和杀nitro硫磷）的应用技术，并分析降解产物和工艺。农药降解效率（％）通过配备有光电二极管阵列检测器（DAD）的高效液相色谱（HPLC）进行监测，而矿化度则通过总有机碳分析（TOC）来确定。水蚤用于筛选降解方法的环境安全方面，即用于评估降解后获得的溶液的毒性。另外，利用地表河水来检查有机物对农药降解的可能影响。使用具有三重四极杆质谱检测器的气相色谱仪（GC-MS / MS）以及结合了线性离子阱的超高效液相色谱仪，Orbitrap质谱仪（UHPLC-LTQ Orbitrap MS）和简单的方法来鉴定农药降解产物提出了农药降解机理。使用二氧化氯成功去除水中的农药，导致较高的降解效率（马拉硫磷98％，杀81硫磷81％）。达到部分矿化作用，水蚤在含有降解产物的水中（与母体农药相比），死亡率降低了，这表明所形成的溶液的毒性低于母体农药。在萨瓦河水中测得的降解率较低（马拉硫磷为80％，杀and硫磷为72％），表明这种天然存在的地表水中所含有机物的影响。结果证明，二氧化氯可以用作从水中成功去除这些OPP的试剂。