College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China.
College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China; State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control, South China Institute of Environmental Sciences, Ministry of Ecology and Environment, Guangzhou 510535, China.
Sci Total Environ. 2023 Sep 10;890:164251. doi: 10.1016/j.scitotenv.2023.164251. Epub 2023 May 16.
The discharge of substantial amounts of N-nitrosamines-contained wastewater into receiving rivers can significantly deteriorate water quality, as these carcinogenic compounds can be easily transported into groundwater and drinking water systems. This study investigated the distribution of eight species of N-nitrosamines in river water, groundwater, and tap water located in the center of the Pearl River Delta (PRD), China. The results showed that three major N-nitrosamines, including N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), and N-nitrosodibutylamine (NDBA), with concentrations of up to 64 ng/L, were observed in river water, groundwater, and tap water, whereas the other compounds occurred sporadically. In river water and groundwater, high concentrations of NDMA, NDEA, N-nitrosomorpholine (NMOR), and NDBA were found in industrial and residential lands as compared to agricultural lands owing to the influence of various human activities. The primary sources of N-nitrosamines in river water were industrial and domestic wastewater, and the infiltration of river water was responsible for the high levels of N-nitrosamines in groundwater. Among the target N-nitrosamines, NDEA and NMOR with long biodegradation half-lives (>4 days) and low LogK values (<1) displayed the highest potential for groundwater. N-nitrosamines in groundwater and tap water pose significant potential cancer risks to residents, especially children, and juveniles, with lifetime cancer risks of over 10, necessitating advanced water treatments for drinking water and critical controls on primary industrial discharge in urban areas.
大量含有 N-亚硝胺的废水排入受纳河流会显著恶化水质，因为这些致癌化合物很容易被输送到地下水和饮用水系统中。本研究调查了中国珠江三角洲（PRD）中心地区河流水、地下水和自来水中 8 种 N-亚硝胺的分布情况。结果表明，在河流水、地下水和自来水中均检测到三种主要的 N-亚硝胺，包括浓度高达 64ng/L 的 N-亚硝基二甲胺（NDMA）、N-亚硝基二乙胺（NDEA）和 N-亚硝基二丁胺（NDBA），而其他化合物则零星出现。在河流水和地下水中，由于各种人类活动的影响，工业和居民区的 NDMA、NDEA、N-亚硝基吗啉（NMOR）和 NDBA 浓度较高，而农业区的浓度较低。河水中 N-亚硝胺的主要来源是工业和生活污水，河水的渗透是地下水中 N-亚硝胺含量高的原因。在所研究的 N-亚硝胺中，生物降解半衰期较长（>4 天）和 LogK 值较低（<1）的 NDEA 和 NMOR 对地下水的潜在影响最大。地下水和自来水中的 N-亚硝胺对居民，特别是儿童和青少年构成了重大的潜在致癌风险，终生致癌风险超过 10%，因此需要对饮用水进行先进的水处理，并对城市地区的主要工业排放进行严格控制。
