清江流域亚硝胺及其前体物质的分布特征及风险评价  

Occurrence and Risk Assessment of N-nitrosamines and Their Precursors in Qingjiang River Basin

作　　者：李梦轩 陈英杰 陈文文 黄焕芳 丁洋 邢新丽[1] 陆燕勤[3] 祁士华[1,2] LI Meng-xuan;CHEN Ying-jie;CHEN Wen-wen;HUANG Huan-fang;DING Yang;XING Xin-li;LU Yan-qin;QI Shi-hua(State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430074,China;School of Environmental Studies,China University of Geosciences,Wuhan 430074,China;College of Environmental Science and Engineering,Guilin University of Technology,Guilin 541006,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;Key Laboratory of Land Resources Evaluation and Monitoring in Southwest,Ministry of Education,Sichuan Normal University,Chengdu 610066,China)

机构地区：[1]中国地质大学(武汉)生物地质与环境地质国家重点实验室,武汉430074 [2]中国地质大学(武汉)环境学院,武汉430074 [3]桂林理工大学环境科学与工程学院,桂林541006 [4]生态环境部华南环境科学研究所国家环境保护水环境模拟与污染控制重点实验室,广州510535 [5]四川师范大学西南土地资源评价与监测教育部重点实验室,成都610066

出　　处：《环境科学》2024年第7期3930-3940,共11页Environmental Science

基　　金：国家自然科学基金项目(42067048);广西自然科学基金项目(2020GXNSFAA159169);广西高校中青年教师科研基础能力提升项目(2020KY06037)。

摘　　要：亚硝胺是一类具有高致癌性和致突变性的含氮有机污染物.支流水系作为我国中小城镇的主要饮用水源,其亚硝胺的污染情况尚不明确,关于支流河水中亚硝胺及其前体物质浓度的研究仍十分缺乏.以水体中常见8种亚硝胺为研究对象,检测了长江一级支流清江河水及氯胺化处理后水样中亚硝胺浓度组成特征,并针对重要的污水排放源进行重点监测,分析亚硝胺及其前体物质的环境影响因素,评估其健康和生态风险.结果表明,清江河水共检出6种亚硝胺,其中主要亚硝胺为NDMA[(10±15)ng·L^(-1)]、NDEA[(9.3±9.3)ng·L^(-1)]和NDBA[(14±7.8)ng·L^(-1)],氯胺化反应后的水样中有7种亚硝胺检出,主要为NDMA-FP[(46±21)ng·L^(-1)]、NDEA-FP[(26±8.3)ng·L^(-1)]和NDBA-FP[(22±13)ng·L^(-1)];河水中亚硝胺的浓度分布整体呈现为中游高于上游和下游,在有污水排放与支流汇入点的亚硝胺浓度明显高于其他点位;对污水直接排放点的监测发现,携带有亚硝胺及其前体物质的污水输入是河水中亚硝胺的主要来源;此外,3种主控污染物NDMA、NDBA和NDEA的浓度存在一定相关性,主要原因是其存在相似的污水来源;饮用水源地亚硝胺浓度对当地居民存在潜在致癌风险(2.4×10^(-5));此外,由于清江具有较高的亚硝胺生成潜能,其饮用水致癌风险可能会更高;生态风险评价表明,亚硝胺对于清江流域的生态风险商值低于0.002,生态风险可忽略不计.N-nitrosamines are a type of nitrogen-containing organic pollutant with high carcinogenicity and mutagenicity.In the main drinking water sources of small and mediumsized towns in China,the contamination levels of N-nitrosamines remain unclear.In addition,there is still lack of research on the concentration of N-nitrosamines and their precursors in tributary rivers.In this study,eight N-nitrosamines and their formation potentials(FPs)were investigated in the Qingjiang River,which is a primary tributary of the Yangtze River.The sewage discharge sites were also monitored,and the environmental influencing factors,carcinogenic and ecological risks caused by N-nitrosamines,and their precursors were evaluated.The results showed that six N-nitrosamines were detected in water samples of the Qingjiang River,among which NDMA[(10±15)ng·L^(-1)],NDEA[(9.3±9.3)ng·L^(-1)],and NDBA[(14±7.8)ng·L^(-1)]were the dominant N-nitrosamines,whereas seven N-nitrosamines were detected in chloraminated water samples,among which NDMA-FP[(46±21)ng·L^(-1)],NDEA-FP[(26±8.3)ng·L^(-1)],and NDBA-FP[(22±13)ng·L^(-1)]were the dominant N-nitrosamine FPs.The concentrations of N-nitrosamines in the middle reaches of the Qingjiang River were higher than those in the upper and lower reaches.Furthermore,the concentrations of N-nitrosamines in the sample sites of sewage discharge and tributaries were significantly higher than those in other sampling sites.The monitoring results at the direct sewage discharge points indicated that the main source of N-nitrosamines in river water was the sewage carrying N-nitrosamines and their precursors.In addition,the concentrations of the three dominant N-nitrosamines including NDMA,NDBA,and NDEA were positively correlated with each other,mainly because of their similar sewage sources.The average carcinogenic risk to residents due to N-nitrosamine in drinking water sources was 2.4×10^(−5),indicating a potential carcinogenic risk.Moreover,due to the high concentrations of N-nitrosamine formation potentials i

关 键 词：清江流域 亚硝胺 生成势(FP) 致癌风险 生态风险 

分 类 号：X522[环境科学与工程—环境工程]