摘要

    磺酰胺（SAs）是使用最广泛的抗生素，经常在污水处理厂的废水中被检测到。在这项研究中，在实验室规模的土壤含水层处理（SAT）系统中，四种典型的SA（磺胺嘧啶（SDZ），磺胺甲恶唑（SMX），磺胺吡啶（SPD）和磺胺二甲基嘧啶（SMT））的去除趋势及其氯化行为，进行了评估。在稳态运行的SAT中，合成水样品中SA的68.2–88.9％（初始浓度为10μgL-1）被有效去除，对磺胺嘧啶而言最高，而对磺胺二嗪而言则最低。具体而言，土壤中的好氧生物降解在去除SA中起重要作用，分别对SMT，SMX，SPD和SDZ去除贡献了55.7％，57.8％，61.1％和74.0％。苯胺基团的裂解和SAs的脱硫是其在土壤退化过程中降解的主要途径。随后的氯化可以部分消除SAT废水中的SA，但不能完全消除，SDZ的去除率为8.21％，SMX的去除率为7.45％，SPD的去除率为14.21％，SMT的去除率为16.52％。苯胺基团的亲电取代和与脱硫产物的反应产生了不同的氯化副产物。源自SAT生物降解的SA的中间体有助于形成氯化副产物和抗生素抗性基因（ARG），特别是对于好氧生物降解条件下产生的有机化合物而言。综上所述，我们的发现表明，由于高浓度的ARGs和氯化副产物的前体，特别是在传统的氯化过程中，充电样品中大量存在的SA会引起健康问题。

    Sulfonamides (SAs), the most widely used antibiotics, are frequently detected in wastewater treatment plant effluent. In this study, the removal trends of four typical SAs (sulfadiazine (SDZ), sulfamethoxazole (SMX), sulfapyridine (SPD) and sulfamethazine (SMT)) in lab-scale soil aquifer treatment (SAT) systems, as well as their chlorination behaviors, were evaluated. As much as 68.2–88.9% of SAs in the synthetic water samples (10 μg L−1 initial concentration) were efficiently removed during steady-state operated SAT, which was the highest for sulfadiazine and lowest for sulfamethazine. Specifically, aerobic biodegradation in the soil played a great role in SA removal and contributed 55.7%, 57.8%, 61.1% and 74.0% to SMT, SMX, SPD and SDZ removal, respectively. Cleavage of the aniline group and desulfation of the SAs were the main pathways for their degradation during soil degradation. Subsequent chlorination could partially eliminate the SAs in the SAT effluent but not entirely, with a removal rate of 8.21% for SDZ, 7.45% for SMX, 14.21% for SPD, 16.52% for SMT, respectively. Electrophilic substitution of the aniline group and reaction with desulfation products produced different chlorinated by-products. The intermediates of the SAs originating from the SAT biodegradation contributed to the formation of chlorinated by-products and antibiotic resistance genes (ARGs), especially for organic compounds generated under aerobic biodegradation conditions. Taken together, our findings demonstrated that the abundant existence of SAs in the recharging samples would lead to health concerns due to the high concentrations of ARGs and precursors of chlorination by-products, especially with traditional chlorination processes.

    https://pubs.rsc.org/no/content/articlelanding/2020/ew/d0ew00270d/unauth#!divAbstract