Chen Zhuo, Valentine Richard L
Department of Civil & Environmental Engineering, University of Iowa, Iowa City, Iowa 52242-1527, USA.
Environ Sci Technol. 2008 Jul 15;42(14):5062-7. doi: 10.1021/es8006673.
NDMA is a recently recognized disinfection byproduct that can be formed by a reaction of monochloramine with natural organic matter (NOM). This study was undertaken to examine the influence of various preoxidation strategies (including prechlorination) on the subsequent formation of NDMA and to determine how this is correlated to the subsequent loss in specific UV absorbance (SUVA) that preoxidation causes. Batch experiments were conducted using surface-water-derived NOM exposed to various oxidants that included free chlorine, permanganate, hydrogen peroxide, and ozone. Photochemical oxidation was also studied by exposing the water to simulated sunlight The amount of NDMA formed after monochloramine was added or formed in situ, in the case when free chlorine was the preoxidant, was significantly reduced by these treatments. The reduction was proportional to the reduction in SUVA that also occurred as a consequence of these treatments indicating that SUVA may be a good surrogate for NDMA precursor content. Furthermore, the change in NDMA formation per unit change in SUVA was a constant that did not depend on the nature of the oxidant
N-亚硝基二甲胺（NDMA）是一种最近才被认识到的消毒副产物，它可由一氯胺与天然有机物（NOM）反应形成。本研究旨在考察各种预氧化策略（包括预氯化）对随后NDMA形成的影响，并确定其与预氧化导致的特定紫外吸光度（SUVA）的后续损失之间的关联。使用来自地表水的NOM进行批量实验，使其暴露于包括游离氯、高锰酸盐、过氧化氢和臭氧在内的各种氧化剂中。还通过将水暴露于模拟阳光下研究光化学氧化。当游离氯作为预氧化剂时，添加一氯胺后或原位形成的NDMA量，通过这些处理显著减少。这种减少与这些处理导致的SUVA减少成比例，表明SUVA可能是NDMA前体含量的良好替代指标。此外，SUVA每单位变化时NDMA形成的变化是一个常数，不依赖于氧化剂的性质。
