College of Food Science, Shenyang Agricultural University, Shenyang, China.
College of Food and Chemical Engineering, Shaoyang University, Shaoyang, China.
J Sci Food Agric. 2022 Dec;102(15):7072-7078. doi: 10.1002/jsfa.12068. Epub 2022 Jul 2.
Treatment by ozone water is an emerging technology for the degradation of pesticide residues in vegetables. The ozone dissolved in water generates hydroxyl radicals ( OH), which are highly effective in decomposing organic substances, such as malathion and carbosulfan.
We found that washing pak choi with 2.0 mg L ozone water for 30 min resulted in 58.3% and 38.2% degradation of the malathion and carbosulfan contents respectively, and the degradation rates of these pure pesticides were 83.0% and 66.3% respectively. In addition, the 'first + first'-order reaction kinetic model was found to predict the trend in the pesticide content during ozone water treatment. Based on investigations by gas chromatography-mass spectrometry combined with the structures of the pesticides, the by-products generated were identified. More specifically, the ozonation-based degradation of carbosulfan generated carbofuran and benzofuranol, whereas malathion produced succinic acid and phosphoric acid. Although some new harmful compounds were formed during degradation of the parent pesticides, these were only present in trace quantities and were transient intermediates that eventually disappeared during the reaction.
Our results, therefore, indicate that ozone water treatment technology for pesticide residue degradation is worthy of popularization and application. © 2022 Society of Chemical Industry.
臭氧水的处理是一种新兴的技术，可用于降解蔬菜中的农药残留。臭氧溶于水中会生成羟基自由基（OH），它在分解有机物质（如马拉硫磷和涕灭威）方面非常有效。
我们发现，用 2.0mg/L 的臭氧水清洗小白菜 30 分钟，可分别使马拉硫磷和涕灭威的含量降解 58.3%和 38.2%，而这两种纯农药的降解率分别为 83.0%和 66.3%。此外，发现“一级+一级”反应动力学模型可以预测臭氧水处理过程中农药含量的趋势。基于气相色谱-质谱联用技术结合农药结构的研究，鉴定了生成的副产物。更具体地说，臭氧氧化涕灭威生成了呋喃丹和苯并呋喃醇，而马拉硫磷则生成了琥珀酸和磷酸。尽管在母体农药的降解过程中形成了一些新的有害化合物，但这些化合物仅以痕量存在，并且是反应过程中最终消失的瞬态中间体。
因此，我们的结果表明，臭氧水用于农药残留降解的处理技术值得推广和应用。 © 2022 英国化学学会。
