在化前和化后,从人为化合物中形成N-Nitrosodimethylamine,具有特征的低治疗剂量
Klon D C Hinneh1,2, Junki Okabe3, Koji Kosaka4
1Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Katsura, Kyoto, Nishikyo, 615-8540, Japan. hinneh.klon.8i@kyoto-u.ac.jp.
概括
在饮用水中识别N-二甲基胺 (NDMA) 前体是关键. 这项研究使用低剂量臭氧和胺来评估NDMA形成潜力,发现一些前体仍然存在,特别是TMDS,可能超过安全的NDMA水平.
科学领域:
- 环境化学环境化学
- 水处理 处理水的方法
- 分析化学 分析化学
背景情况:
- N-二甲基胺 (NDMA) 是成品饮用水中的污染物.
- 识别和控制NDMA前体对于最小化其存在至关重要.
- 以前的前体鉴定方法使用高剂量,不反映现实世界治疗条件.
研究的目的:
- 在低剂量臭氧化和化后评估特定有机化合物的NDMA形成潜力 (NDMAFP) 产量.
- 评估臭氧化前和化后在减少N,N-二甲基胺 (DMA) 和N,N-二甲基 (DMH) 前体的NDMAFP产量的有效性.
- 调查水矩阵 (Milli-Q,污水废水,湖水) 对前体NDMAFP产量的影响.
主要方法:
- 应用臭氧 (O3) 的特征性低处理剂量到溶解有机碳 (DOC) (0.8 mg/mg) 和 (NH2Cl) (2.5 ± 0.2 mg Cl2/L).
- 在臭氧化前和化后,对具有DMA和DMH功能的目标化合物的评估NDMAFP产量.
- 在pH缓冲的Milli-Q水,污水废水和湖水样本中测试了前体反应性.
主要成果:
- 在臭氧化前和化后,DMH类化合物的O3-NDMAFP产量显著降低到无法检测的水平.
- NH2Cl-NDMAFP的NH2Cl-反应前体产量显著下降,但N,N-二甲基胺 (DMBzA) 类化合物仍然对NDMAFP有所贡献.
- 1,1,1',1'-tetramethyl-4,4'-(methylene-di-p-phenylene) disemicarbazide (TMDS) 的O3-NDMAFP产量在污水废水中没有显著下降,估计NDMAFP的约315 ng/L,超过了指导值.
结论:
- 低剂量的臭氧和胺有效地减少了某些NDMA前体,但DMBzA类化合物可以持续存在.
- 前体1,1,1',1'-tetramethyl-4,4'-(methylene-di-p-phenylene) disemicarbazide (TMDS) 是一个重要的NDMA前体,特别是在复杂的矩阵中,如污水废水.
- 饮用水中NDMA的有效控制策略必须考虑特定的前体及其在不同水矩阵中的行为.
相关概念视频
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