室内表面和尘埃上的化学污染物的基氧化
William D Fahy1, Yufeng Gong1,2, Shenghong Wang3
1Department of Chemistry, University of Toronto, Toronto, ON M5S 3H6, Canada.
概括
室内半挥发性有机污染物,如2-乙基) 酸盐 (DEHP) 经历氧化,形成具有更长寿命和更高人体暴露风险的产品. 室内这种多相化学反应比以前理解的更为严重的健康问题.
科学领域:
- 环境化学环境化学
- 毒理学 毒理学 毒理学
- 室内空气质量 室内空气质量
背景情况:
- 人类暴露于室内半挥发性有机污染物 (SVOCs),这些污染物在室内表面持续存在.
- 室内表面促进多相化学与氧化剂,如基基 (OH).
- 以前的研究表明选择性氧化,但非选择性OH反应性表明未知的室内转化途径.
研究的目的:
- 调查室内 bis(2-乙烯基) 甲酸盐 (DEHP) 的OH基氧化产物的发生和影响.
- 评估DEHP氧化产品的室内寿命和人类暴露潜力.
- 评估这些转化产品的内分泌干扰活性和毒性.
主要方法:
- 用非目标高分辨率质谱测试对60种已知DEHP氧化产品的室内灰尘和DEHP薄膜进行选.
- 实验室实验模拟室内条件,以研究多相OH基反应.
- 使用PROTEX模型和多媒体室内化学命运模型来模拟化学生命周期和暴露.
主要成果:
- 在室内尘埃中检测到30多种DEHP氧化产物,10种在DEHP薄膜中检测到,证实了室内多相OH反应.
- 与DEHP相比,这些氧化产品具有较长的室内寿命和增加的人类暴露潜力.
- 一些产品比DEHP更强烈的内分泌干扰剂,大多数产品具有未表征的毒性.
结论:
- 室内多相OH激素化学产生持久性污染物,对人类健康造成重大风险.
- 同时暴露的氧化产品的添加剂有毒作用引起了人们的整体健康问题.
- 进一步的研究对于了解这种室内化学转变的广泛影响至关重要.
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