Abstract This study evaluated gamma radiation-enhanced sulfamethazine (SMT) degradation, which belongs to the heterocyclic sulfonamides, in different conditions in aqueous solution. The results showed that gamma irradiation could increase the SMT removal in aqueous solution, and the SMT degradation kinetic follow the modified pseudo-first-order kinetic. The degradation rate was nearly 95% at the absorbed dose of 4 kGy. The removal of total organic carbon (TOC) and total nitrogen (TN) could be also induced. When the radiation dose was 5 kGy, the removal rates were only about 6.8% and 10.5% for TOC and TN, respectively. Some ions including HCOO−, CH3COO− and SO4 2− released during SMT degradation were studied. The biodegradability and toxicity of intermediate products of the SMT degradation were also proposed in this experiment. The biodegradability of the SMT can be improved by the intermediate products of SMT degradation at the radiation dose of 1, 2 and 5 kGy. Gamma radiation could be used as a pretreatment technology before the biodegradation process of pharmaceutical waste water.

中文翻译：

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γ射线对磺胺二甲嘧啶类抗生素的降解、生物降解性和毒性评价

摘要 本研究评估了伽马辐射增强的磺胺二甲嘧啶（SMT）在不同条件下在水溶液中的降解，该磺胺属于杂环磺胺类药物。结果表明，γ辐照可以提高水溶液中SMT的去除率，并且SMT降解动力学遵循修正的准一级动力学。在吸收剂量为 4 kGy 时降解率接近 95%。还可以诱导去除总有机碳 (TOC) 和总氮 (TN)。当辐射剂量为 5 kGy 时，TOC 和 TN 的去除率分别仅为 6.8% 和 10.5%。研究了在 SMT 降解过程中释放的一些离子，包括 HCOO-、CH3COO- 和 SO4 2-。本实验还提出了 SMT 降解中间产物的生物降解性和毒性。SMT 的生物降解性可以通过 SMT 降解的中间产物在 1、2 和 5 kGy 的辐射剂量下得到改善。伽马辐射可作为制药废水生物降解前的预处理技术。