在城市的河口中,氨酸加速剂/抗氧化剂的空间-垂直和多媒体模式令人难以理解
1Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, Shanghai 200241, China.
Water research
|September 14, 2024
概括
在长江河口中检测到氨酸加速剂和抗氧化剂 (AA) 以及它们的转化产品 (TP). 这些工业化学品对水生有毒性中等至高,并被运往东中国海.
科学领域:
- 环境化学环境化学
- 生态毒理学 生态毒理学
- 海洋污染 海洋污染
背景情况:
- 氨酸加速剂和抗氧化剂 (AAs) 是产量大,在环境中广泛存在的工业化学品.
- 关于AA及其转化产品 (TP) 的环境行为和生态毒理学影响的数据有限.
- 城市化河口是污染物运输和转化的关键接口.
研究的目的:
- 量化水,悬浮颗粒物 (SPM) 和长江河口 (YRE) 的沉积物中的AA(TP).
- 在一个高度城市化的河口系统中调查AA(TPs的环境命运,分布和生态风险.
- 估计从YRE到东中国海的AA(TP) 流量.
主要方法:
- 从YRE收集了配对的水,SPM和沉积物样本.
- 使用染色学和质谱学分析了24个AA(TP).
- 计算的疏水性 (KOW),SPM分数,沉积物吸附系数 (KOC) 和风险系数 (RQ).
主要成果:
- 总AA(TP) 度的中位数为0.73 ng/g dw (沉积物),34.4 ng/L (地表水) 和39.6 ng/L (地下水).
- 双胺 (DPA) 在SPM中占主导地位,而1,3-双胺 (DPG) 和二环胺 (DChA) 在水和沉积物中普遍存在.
- AA(TP) 分割和吸附与疏水性正相关;RQs表明在某些地点中等到高的水生毒性.
结论:
- 人类产生的排放和降解影响了YRE中的AA(TP) 分布.
- AA(TP) 通过水 (每年5.90365.5) 和沉积物 (每年4.231,100公斤) 流向东中国海.
- 这项研究提供了对河口环境中这些新兴污染物的环境过程和生态风险的关键见解.
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