基于综合评分法和风险商值法筛选长江流域特征污染物及不同介质中的风险污染物

Screening of Characteristic Pollutants and Risk Pollutants in Different Media in the Yangtze River Basin Using Comprehensive Evaluation and Risk Quotient Methods

随着经济快速发展、人口增加和城市化进程的加快,在长江流域内频繁检出各种污染物,威胁水生生态系统及人体健康.通过构建多指标综合评分法筛选识别长江流域特征污染物,并采用风险商值法得出水样和沉积物中的风险污染物.结果表明,长江流域共检出11类155种污染物,对污染物综合得分进行K均值聚类分析,根据每个聚类中的污染物数目按照分数高低进行分级并记为Ⅰ~Ⅵ.将43种Ⅰ级和Ⅱ级高分值污染物列入特征污染物清单,分别是11种多环芳烃、11种有机氯农药、10种多氯联苯、8种二英类、2种重金属和1种邻苯二甲酸酯.文献统计结果表明,水样污染物浓度和沉积物含量中位数浓度前5种都是重金属、多环芳烃、邻苯二甲酸酯、双酚类及药品和个人护理品,而且顺序完全一致.根据风险最大化原则,以污染物在长江流域水样中的最高浓度计算风险商值(RQ),水样中共筛选出38种风险污染物(RQ≥0.1),其中RQ≥1的高风险污染物共8种,包括苯并[a,h]蒽、蒽、苯并[a]蒽、芘、甲氧滴滴涕、艾氏剂、2,4'-滴滴伊和镉.沉积物中共筛选出39种风险污染物,其中高风险污染物15种,包括苯并[b]荧蒽、蒽、苊、荧蒽、镉、铅、铬、砷、硒、邻苯二甲酸二丁酯、邻苯二甲酸二甲酯、邻苯二甲酸二异丁酯、诺氟沙星、全氟丁酸和双酚A.此外,风险污染物中除了现行政策文件管控的污染物,也包含一些新污染物(水样中含有10种,沉积物中9种),且主要以抗生素类污染物为主.研究可为相关管理部门对长江流域内污染物监测和管理方案的拟定提供重要参考,对长江流域生态环境保护和治理具有重要意义.

A variety of pollutants have frequently been detected in the Yangtze River Basin with the rapid economic development,the population increase,and the acceleration of urbanization,which threaten the aquatic ecosystem and human health.A multi-criteria comprehensive evaluation method was developed to identify the characteristic pollutants,and the risk quotient method was used to derive the risk pollutants in water and sediment samples in this article.A total of 155 pollutants from 11 categories were detected in the Yangtze River Basin according to the literature research.Then,the K-means method was used to analyze the cluster of pollutant comprehensive scores.All pollutants were graded based on their scores and recorded asⅠ-Ⅵaccording to the number of cases in each cluster.A total of 43 pollutants with high scores ofⅠandⅡwere listed as the characteristic pollutants,which included 11 polycyclic aromatic hydrocarbons,11 organochlorine pesticides,10 polychlorinated biphenyls,eight dioxins,two heavy metals,and one phthalate ester.The top five median concentrations of contaminants in water and sediment samples were heavy metals,polycyclic aromatic hydrocarbons,phthalates esters,bisphenols,and pharmaceuticals and personal care products.According to the principle of risk maximization,the risk entropy value(RQ)was calculated based on the highest pollutant concentration.A total of 38 risky pollutants were screened in the water samples(RQ≥0.1).There were eight high-risk pollutants with RQ≥1,which included benzo[a,h]-anthracene,anthracene,benzo[a]anthracene,pyrene,methoxychlor,aldrin,2,4'-dichlorodiphenyl,and cadmium.There were 15 high-risk contaminants in the sediment,which included benzo[b]fluoranthene,anthracene,acenaphthene,fluoranthene,cadmium,lead,chromium,arsenic,selenium,dibutyl phthalate,dimethyl phthalate,diisobutyl phthalate,norfloxacin,perfluorobutyric acid,and bisphenol A.The risk pollutants contained emerging pollutants,which included ten pollutants in water samples and nine pollutants in sediments.Antibiotic pollutants accounted for the largest proportion of these emerging pollutants.The information provided in this article may be useful for the relevant departments to monitor the pollutants and propose management programs for the Yangtze River Basin.Additionally,it is of great significance for the ecological environmental protection and management of the Yangtze River Basin.