School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, China.
Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management, Institute of Eco-environmental and Soil Sciences, National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Academy of Sciences, Guangzhou, 510650, China.
Chemosphere. 2023 Oct;338:139541. doi: 10.1016/j.chemosphere.2023.139541. Epub 2023 Jul 17.
This study aimed to achieve toxicity control of sulfadiazine (SDZ) and pirimiphos-methyl (PMM) via the UV/HO process by optimizing the reaction parameters. The results show that both drugs had a good degradation effect under the following parameters: a HO molar ratio of 1:200, and neutral conditions. SDZ and PMM could be degraded by more than 99% within 3 min, respectively. In the Daphnia magna acute toxicity assay and Vibrio fischeri inhibition assay, both SDZ and PMM exhibited a phenomenon of increasing toxicity. Additionally, through the use of density functional theory (DFT) calculation and HPLC-QTOF-MS, 21 transformation products (TPs) were identified, and the principal degradation pathways were proposed. The toxicity of the TPs was determined by comparing the QSAR prediction results with toxicity test data. As a result, under the higher UV light intensity (2300 μW/cm) and neutral conditions, SDZ showed highest toxicity, whereas PMM showed lowest toxicity under the lowest UV light intensity (450 μW/cm) and neutral conditions. Four main toxic TPs were identified, and their yields could be reduced by adjusting the reaction parameters. Therefore, the selection of appropriate reaction parameters could reduce the production of toxic TPs and ensure the safety of water environment.
本研究旨在通过优化反应参数，实现磺胺嘧啶（SDZ）和毒死蜱（PMM）的光催化氧化过程毒性控制。结果表明，在以下参数下，两种药物均具有良好的降解效果：HO 摩尔比为 1:200，中性条件。SDZ 和 PMM 可在 3 分钟内分别降解 99%以上。在大型蚤急性毒性试验和发光菌抑制试验中，SDZ 和 PMM 均表现出毒性增强的现象。此外，通过使用密度泛函理论（DFT）计算和 HPLC-QTOF-MS，鉴定出 21 种转化产物（TPs），并提出了主要降解途径。通过将 QSAR 预测结果与毒性试验数据进行比较，确定了 TPs 的毒性。结果表明，在较高的紫外光强度（2300 μW/cm）和中性条件下，SDZ 表现出最高的毒性，而在较低的紫外光强度（450 μW/cm）和中性条件下，PMM 表现出最低的毒性。鉴定出四种主要的有毒 TPs，通过调整反应参数可以降低其生成量。因此，选择适当的反应参数可以减少有毒 TPs 的产生，确保水环境的安全。
