在水中的基酸液晶单体的光化学行为和毒性演变
Chao Li1, Shaochen Li1, Xiao Zhang1
1Engineering Lab for Water Pollution Control and Resources Recovery, State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, School of Environment, Northeast Normal University, Changchun 130117, China.
Journal of hazardous materials
|April 19, 2024
概括
液晶单体 (LCM) 是一种持久性污染物. 这项研究揭示了它们在水中的快速光化学降解,主要是通过激发的三重状态和活性氧物种,其中一些产品保留了毒性.
科学领域:
- 环境化学环境化学
- 摄影化学的使用.
- 生态毒理学 生态毒理学
背景情况:
- 液晶单体 (LCM) 是具有显著毒性的新兴环境污染物.
- 了解LCMs的环境命运和转变对于生态风险评估至关重要.
研究的目的:
- 在水生环境中研究基酸LCMs的光化学转化动力学,机制和光诱导毒性.
- 阐明溶解有机物和活性氧物种在LCM光解中的作用.
- 确定LCM对基激素的反应性,并开发预测方法.
主要方法:
- 在水溶液中的光化学降解实验.
- 使用分析技术识别光解产品和光解途径.
- 照片诱导毒性的评估.
- 计算模拟用于反应速率常数的估计.
主要成果:
- 基酸LCM在水中呈现快速光解,其半衰期低于30分钟.
- 溶解的有机物通过光屏蔽和灭效应抑制LCM光解.
- 光解通过激发的三重状态进行,其中基 (⋅OH),单氧 (1O2) 和超氧基 (⋅O2-) 是主要的反应物种.
- 主要的降解途径包括键裂解,⋅OH替代/添加和除.
- 一些OH添加/替代产品的毒性与原始LCM相美.
- 轻微微粒细胞对⋅OH (kOH > 1 × 109 M-1 s-1) 的反应性很高.
结论:
- 基酸LCM在阳光照明的水生环境中由于快速光解而相对不持久.
- 溶解有机物的存在可以影响LCMs的环境持久性.
- 虽然LCMs降解,但它们的转化产品可能会带来持续的生态风险.
- 量子化学计算提供了一种可靠的方法来估计类似的LCMs与⋅OH的反应性,有助于未来的风险评估.
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