望城饮用水源地周边土壤多环芳烃的污染特征和风险评价  

Contamination characterization and risk assessment of polycyclic aromatic hydrocarbons in soils around a drinking water source in Wangcheng district

作　　者：谭菊 伍钢 许云海[3] 杨海君[3] TAN Ju;WU Gang;XU Yunhai;YANG Haijun(Changsha Environmental Monitoring Center Station,Changsha,Hunan 410001,China;Hunan Hualang Environmental Testing Co.Ltd,Changsha,Hunan 410114,China;College of Plant Protection,Hunan Agricultural University,Changsha,Hunan 410128,China)

机构地区：[1]长沙市环境监测中心站,湖南长沙410001 [2]湖南省华朗环境检测有限公司,湖南长沙410114 [3]湖南农业大学植物保护学院,湖南长沙410128

出　　处：《湖南农业大学学报（自然科学版）》2020年第2期206-214,共9页Journal of Hunan Agricultural University(Natural Sciences)

基　　金：湖南省自然科学基金项目(2018JJ5015);长沙市科学技术局项目(kq1801021)。

摘　　要：以长沙市望城区集中式饮用水源地一级和二级保护区周边0~20 cm土壤为研究对象,于2018年采用网格布点法在一级和二级保护区分别布设3个(1#~3#)和12个(4#~15#)采样点,其中11#~15#采样点于2014年布设,探究土壤中苊(Ace)、苊烯(Acy)、蒽(Ant)、菲(Phe)、芴(Flu)、苯并[a]蒽(BaA)、芘(Pyr)、屈(Chr)、荧蒽(Fla)、苯并[a]芘(BaP)、苯并[b]荧蒽(BbF)、苯并[k]荧蒽(BkF)、二苯并[a,h]蒽(DBA)、苯并[g,h,i]苝(BghiP)、茚并[1,2,3–c,d]芘(IcdP)共15种多环芳烃(PAHs)的污染水平及来源,运用毒性当量浓度值及终生癌症风险增量模型对土壤中PAHs进行风险评价。结果表明:水源地保护区土壤中15种PAHs总含量为75.22~5 617.86 ng/g,均值为670.96 ng/g,其中7种致癌PAHs(BaA、Chr、BbF、BkF、BaP、DBA、IcdP)的含量为12.13~2 989.26 ng/g,均值为319.80 ng/g;2#和4#土壤样品中多环芳烃均为中度污染,12#土壤样品中多环芳烃为重度污染,其他点位土壤均处于轻度污染或未受污染;荧蒽、芘、菲是水源地保护区土壤中的主要污染因子;除一级保护区土壤中芴含量稍高于二级保护区外,水源地一级保护区土壤中其余14种PAHs单体含量均低于二级保护区;除12#点位样品外,其他点位样品土壤中3环和4环PAHs占比均大于60%;采用特征比值法分析污染物来源,显示水源地一级保护区土壤中PAHs主要来源于石油源和燃烧源的混合污染,主要受区域内交通因素与上游工业、生活废弃物中PAHs迁移与沉降影响,二级保护区土壤中PAHs主要来源于石油源和生物质、煤燃烧的混合污染,可能与区域内人为活动和交通因素有关;健康风险评价结果表明,水源地一级和二级保护区土壤中PAHs的总致癌风险值均在10–6~10–4,存在潜在健康风险。This study aims to investigate the pollution level and source of polycyclic aromatic hydrocarbons(PAHs) in the soil around a centralized drinking water source in Wangcheng district of Changsha, Hunan, China. The 0-20 cm soil in the first and second protection areas of the water source was taken as the research object. In 2018, three(1#-3#) and twelve(4#-15#) soil sampling points were arranged in the first and second protection areas respectively by the grid method, and 11#-15# soil sampling points were arranged in 2014. Fifteen varieties of PAHs including acenaphthene(Ace), acenaphthylene(Acy), anthracene(Ant), phenanthrene(Phe), fluorine(Flu), benzo[a] anthracene(BaA), pyrene(Pyr), chrysene(Chr), fluoranthene(Fla), benzo[a]pyrene(BaP), benzo[b]fluoranthene(BbF), dibenzo[a,h] anthracene(DBA), benzo[g,h,i]perylene(BghiP) and indeno[1,2,3-c,d]pyrene(IcdP) were taken into account. The risk assessment was carried out with the model of toxic equivalent concentration and incremental lifetime cancer risk. Results showed that the contents of 15 PAHs in the soil of the protected area were 75.22-617.86 ng/g with the average of 670.96 ng/g. Among which, the contents of 7 carcinogenic PAHs(BaA, Chr, BbF, BkF, BaP, DBA, IcdP) ranged from 12.13 to 2 989.26 ng/g with the mean of 319.80 ng/g. The soil samples 2# and 4# were moderately contaminated with PAHs, while sample 12# was heavily contaminated, and other samples were mildly contaminated or uncontaminated. Fla, Pyr and Phe were the main pollution factors. The PAHs content in the soil of the first-level protection area was lower than that of the second-level protection area. Apart from 12# sampling point, the PAHs ratio of 3-ring and 4-ring in the soil of the other point samples was more than 60%. Application of the characteristic ratio method to analyze the source of pollutants showed that the PAHs in the first-level protected area of the water source mainly came from the mixed pollution of petroleum and combustion sources, affected by the regional transportation factors an

关 键 词：多环芳烃 污染特征 来源解析 健康风险评价 集中式饮用水源地 长沙市望城区 

分 类 号：X53[环境科学与工程—环境工程]