摘要
河水-地下水交互带是污染物发生富集、降解和转化等生物地球化学过程的重要场所.抗生素作为一类广泛关注的有机污染物,探索其在交互带中的分布特征对认识特殊生境下污染物迁移转化过程具有重要意义.由于交互带氧化还原条件变化敏感,沉积物组成特殊,建立了一种有效提取交互带中22种抗生素及4种磺胺类代谢产物的前处理方法,并对样品初始状态、提取温度、提取液pH值以及有机提取溶剂进行了优化.同时对汉江下游河水-地下水交互带沉积物中的抗生素含量进行分析,结果表明,采用pH=3的乙腈/乙二胺四乙酸二钠(Na_(2)EDTA)-Mcllvaine缓冲液(1∶1,体积比)对未经氧化的沉积物原样在40℃条件下进行3次微波提取,目标抗生素的回收效果最好.汉江下游交互带沉积物中共检出11种抗生素,其中以土霉素(OTC)和氧氟沙星(OFL)为主,最高检出含量分别为6.77 ng·g^(-1)和5.81 ng·g^(-1).不同交互剖面中抗生素含量的垂向分布差异较大,主要与沉积物岩性、抗生素理化性质和地表水-地下水交互作用等影响因素有关.
The river water-groundwater interaction zone is an important area for the enrichment,degradation,and transformation of pollutants and other biogeochemical processes.The distribution characteristics of antibiotics,as organic pollutants of wide concern,in the interaction zone is essential for understanding the migration and transformation process of pollutants in the environment.Due to the sensitive changes in the redox conditions and special composition of sediments in the interaction zone,this study established an effective pretreatment method for extracting 22 antibiotics and four sulfonamide metabolites in the interaction zone,and optimized the initial state of the samples,extraction temperature,pH value of the extraction solution and organic extraction solvent.The content of antibiotics in the sediments of the river water-groundwater interaction zone and lower reaches of the Hanjiang River was also analyzed.The results show that the best recovery of the target compounds is obtained by using pH 3 acetonitrile/Na_(2)EDTA-Mcllvaine buffer(1∶1,volume ratio)to digest and extract the unoxidized sediment samples at 40℃three times using a microwave.A total of 11 antibiotics are detected in the sediments of the interaction zone in the lower reaches of the Hanjiang River,among which oxytetracycline and ofloxacin are the main compounds with the highest concentrations of 6.77 ng·g^(-1)and 5.81 ng·g^(-1),respectively.The vertical distribution of antibiotics in different sediment profiles is significantly different,which may be related to the lithology of sediments,physicochemical properties of antibiotics,and interaction between surface water and groundwater.
作者
李玉琼
童蕾
严涵
尤悦
卢钰茜
刘慧
LI Yu-qiong;TONG Lei;YAN Han;YOU Yue;LU Yu-xi;LIU Hui(School of Environment Studies,China University of Geosciences,Wuhan 430078,China;Geological Survey,China University of Geosciences,Wuhan 430074,China;State Key Laboratory of Biogeology and Environmental Geology,Wuhan 430078,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2021年第11期5294-5302,共9页
Environmental Science
基金
国家自然科学基金重点项目(41830862)
国家自然科学基金项目(41772364)。
关键词
抗生素
磺胺代谢产物
交互带
沉积物提取
分布特征
汉江下游
antibiotics
sulfonamide metabolites
interaction zone
sediment extraction
distribution characteristics
lower reaches of Hanjiang River
