Sorption and Photodegradation Processes Govern Distribution and Fate of Sulfamethazine in Freshwater-Sediment Microcosms
Sorption and Photodegradation Processes Govern Distribution and Fate of Sulfamethazine in Freshwater-Sediment Microcosms
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DOI：
10.1021/es402100g
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发表时间：
2013-10-01
影响因子：
11.4
通讯作者：
Coats, Joel R.
中科院分区：
文献类型：
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作者：
Carstens, Keri L.;Gross, Aaron D.;Coats, Joel R.
抗生素磺胺二甲嘧啶可以从人工农田运输到地表水体。用C-14-苯基磺胺二甲嘧啶在含有完整底泥和池水的小型池塘水中研究了磺胺二甲嘧啶在池塘水中的降解和去向。在模拟径流的池水中加入磺胺二甲嘧啶(初始浓度为5 mg L-1)时，池水中的半衰期为2.7d，半衰期为4.2d。磺胺二甲嘧啶从水柱中呈指数级消散，大部分损失发生在进入沉淀相的过程中。沉积物中可提取的磺胺二甲嘧啶在14d内占使用抗生素的1.9-6.1%，此后下降。磺胺二甲嘧啶主要转化为不可提取的沉淀物结合残留物(应用放射性的40%-60%)和少量的感光产物。从代谢产物的形成和(CO2)-C-14的演化来看，生物降解没有光降解那么显著。在63天的研究结束时，两种光产物占水柱中放射性的15%-30%；光产物是水相和沉淀相中的主要降解物。其他未确认的代谢物单独说明
The antibiotic sulfamethazine can be transported from manured fields to surface water bodies. We investigated the degradation and fate of sulfamethazine in pond water using C-14-phenyl-sulfamethazine in small pond water microcosms containing intact sediment and pond water. We found a 2.7-day half-life in pond water and 4.2-day half-life when sulfamethazine was added to the water (5 mg L-1 initial concentration) with swine manure diluted to simulate runoff. Sulfamethazine dissipated exponentially from the water column, with the majority of loss occurring via movement into the sediment phase. Extractable sulfamethazine in sediment accounted for 1.9-6.1% of the applied antibiotic within 14 days and then declined thereafter. Sulfamethazine was transformed mainly into nonextractable sediment-bound residue (40-60% of applied radioactivity) and smaller amounts of photoproducts. Biodegradation, as indicated by metabolite formation and (CO2)-C-14 evolution, was less significant than photodegradation. Two photoproducts accounted for 15-30% of radioactivity in the water column at the end of the 63-day study; the photoproducts were the major degradates in the aqueous and sediment phases. Other unidentified metabolites individually accounted for