溶解有机物和PPCP之间的反应速率系数的定量结构-活性关系模型
Roujia Du1, Qianxin Zhang1, Bin Wang1
1State Key Joint Laboratory of Environmental Simulation and Pollution Control (SKLESPC), Beijing Key Laboratory for Emerging Organic Contaminants Control, School of Environment, Tsinghua University, Beijing 100084, China.
Journal of hazardous materials
|June 24, 2023
概括
预测药品和个人护理产品 (PPCPs) 在水中的光解率至关重要. 新的定量结构-活性关系 (QSAR) 模型准确地预测了PPCP与溶解有机物 (DOM) 的反应速率,有助于评估环境命运.
科学领域:
- 环境化学环境化学
- 摄影化学的使用.
- 分析水质 分析水质
背景情况:
- 预测水生环境中药品和个人护理产品 (PPCPs) 的光解速率对于了解它们的环境命运至关重要.
- 溶解有机物 (DOM) 和PPCP之间的准确反应速率数据很少,目前对于这个关键的光化学参数没有预测模型.
- PPCP的光反应速率受到自然水中的DOM相互作用的显著影响.
研究的目的:
- 在自然水生环境中开发PPCP光解速率的预测模型.
- 定义和测量一个反应速率系数 (αDOM),描述PPCP的DOM参与的光反应.
- 建立定量结构-活动关系 (QSAR) 模型来预测αDOM值.
主要方法:
- 定义了一种反应速率系数 (αDOM) 对于涉及DOM的PPCP光反应.
- 在9个不同的DOM样本中测量了40个PPCP的αDOM值.
- 通过随机森林方法开发使用化学和水质描述符的QSAR模型,包括正/负值分类器和单独的回归模型.
主要成果:
- 测量的αDOM值表现出显著的变化,范围从 (-2.1 ± 0.1) ×10^10到 (2.2 ± 0.1) ×10^11 M−1 s−1.1.
- QSAR模型表现出强大的预测性能:积极的模型实现了R2adj=0.92和Q2ext=0.86,而负面的模型表现出可接受的性能,R2adj=0.71和Q2ext=0.70.
- 建立了一个综合光解模型,结合了αDOM的QSAR预测,通过灵敏度分析强调了水质参数的重要性.
结论:
- 开发的QSAR模型为预测PPCP在各种水生基质中的光解速率提供了强大的工具.
- 综合光解模型可以更准确地评估PPCP的环境命运.
- 这项研究为预测PPCP在自然水域的行为和持久性提供了宝贵的帮助.
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