产品到母体的博逆转:未知的内分泌干扰风险
Shen Qu1, Edward P Kolodziej, Sarah A Long
1Department of Civil and Environmental Engineering, University of Iowa, 4105 Seamans Center for the Engineering Arts and Sciences, Iowa City, IA 52242-1527, USA.
概括
由于可逆光变化,乙酸 (TBA) 代谢物在地表水中迅速再生. 这种日间循环,取决于温度和pH值,影响对类固醇污染物的环境风险评估.
科学领域:
- 环境化学环境化学
- 生态毒理学 生态毒理学
- 类固醇的新陈代谢
背景情况:
- 乙酸 (TBA) 是一种在肉牛中广泛使用的类固醇增长促进剂.
- 在水生环境中,TBA代谢物被认为是强大的内分泌干扰化合物 (EDC).
- 了解TBA代谢物的环境命运对于生态风险评估至关重要.
研究的目的:
- 研究水生系统中TBA代谢物的光转化途径和产物.
- 评估TBA代谢产物的环境持久性和再生潜力.
- 评估这些发现对类固醇EDCs环境风险评估的影响.
主要方法:
- 进行了基于实验室和现场的光变实验.
- 研究的重点是表层水 (pH 7,25°C) 的代表性条件.
- 分析包括监测TBA代谢物及其光产物的形成和降解.
主要成果:
- 在模拟的地表水条件下观察到TBA代谢物的快速,可逆光化.
- 确定了一种产品转基因逆转机制,导致白天循环和TBA代谢物的再生.
- 证明再生率在很大程度上取决于温度和pH值.
- 显示光产品可以形成TBA代谢物的结构模拟物.
- 其他结构相关的类固醇,包括药品,也出现了类似的反应.
结论:
- TBA代谢物的可逆光变化导致它们在地表水中的大量再生.
- 温度和pH值是影响TBA代谢物循环速度的关键因素.
- 现有的环境命运模型和风险评估可能低估了由于这种再生现象而导致的类固醇EDC的持续性和影响.
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