Potential for natural and enhanced attenuation of sulphanilamide in a contaminated chalk aquifer

作     者：Karen A.Bennett Simon D.Kelly Xiangyu Tang Brian J.Reid 

作者机构：School of Environmental SciencesUniversity of East AngliaNorwich Research ParkNorwich NR4 7TJUK Food and Environmental Protection LaboratoryInternational Atomic Energy Agency1400 ViennaAustria Key Laboratory of Mountain Surface Processes and Ecological RegulationInstitute of Mountain Hazards and EnvironmentChinese Academyof SciencesChengdu 610041China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2017年第29卷第12期

页      面：39-48页

核心收录：

学科分类：0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 0815[工学-水利工程] 

基　　金：Financial support from the Natural Environment Research Council(NERC) Chinese Academy of Sciences President's International Fellowship Initiative(No.2016VEA040)is gratefully acknowledged 

主　　题：Antibiotics Sulphonamide Groundwater contamination Biodegradation Stable isotope fractionation IRMS 

摘      要：Understanding antibiotic biodegradation is important to the appreciation of their fate and removal from the environment. In this research an Isotope Ratio Mass Spectrometry（IRMS）method was developed to evaluate the extent of biodegradation of the antibiotic,sulphanilamide, in contaminated groundwater. Results indicted an enrichment in δ^（13）C of8.44‰ from-26.56（at the contaminant source） to-18.12‰（300 m downfield of the source）.These results confirm reductions in sulphanilamide concentrations（from 650 to 10 mg/L）across the contaminant plume to be attributable to biodegradation（56%） vs. other natural attenuation processes, such as dilution or dispersion（42%）. To understand the controls on sulphanilamide degradation ex-situ microcosms assessed the influence of sulphanilamide concentration, redox conditions and an alternative carbon source. Results indicated, high levels of anaerobic capacity（~50% mineralisation） to degrade sulphanilamide under high（263 mg/L）, moderate（10 mg/L） and low（0.02 mg/L） substrate concentrations. The addition of electron acceptors; nitrate and sulphate, did not significantly enhance the capacity of the groundwater to anaerobically biodegrade sulphanilamide. Interestingly, where alternative carbon sources were present, the addition of nitrate and sulphate inhibited sulphanilamide biodegradation. These results suggest, under in-situ conditions, when a preferential carbon source was available for biodegradation, sulphanilamide could be acting as a nitrogen and/or sulphur source. These findings are important as they highlight sulphanilamide being used as a carbon and a putative nitrogen and sulphur source, under prevailing iron reducing conditions.