为研究城市河流中WWMPs(污水印记药物)的迁移转化行为,以13种典型WWMPs〔AZM(阿奇霉素)、CLM(克拉霉素)、STZ(磺胺噻唑)、TMP(甲氧苄啶)、ATL(阿替洛尔)、PNL(普萘洛尔)、DCF(双氯芬酸)、CLF(氯贝酸)、IBU(布洛芬)、CBM(卡马西平)、CAF(咖啡因)、PRC(扑热息痛)和TCS(三氯生)〕为目标物,通过生物降解试验、吸附试验及光降解试验分析目标物主要的迁移转化机理.结果表明,AZM、CLM、PRC的降解主要是生物作用,不灭菌且有氧条件下的降解率分别可达90%、95%、100%.沉积物对CBM的吸附作用明显,但其难以被水解和生物降解,而且其吸附和解吸是一个相对平衡的过程,导致CBM能够稳定存在.ATL、STZ、PRC和TMP这4种亲水性化合物不易被沉积物吸附,其余9种属疏水性化合物的吸附能力取决于其KOW(辛醇-水分配系数).此外,光降解试验表明,在实际环境中,很多目标物受颗粒物和光敏剂的影响,不易发生直接光降解,TMP、DCF、PNL、CAF和TCS容易发生光降解作用,其在光照和避光的条件下降解率分别为20%和10%、58%和25%、22%和5%、20%和2%、30%和5%.研究显示,城市河流中的WWMPs在生物降解、吸附和光降解共同作用下有明显的降解效果.%This study selected 13 typical wastewater-marking pharmaceuticals ( WWMPs ) ( azithromycin ( AZM ) ;clarithromycin (CLM), sulfathiazole (STZ), trimethoprim (TMP), atenolol (ATL), propranolol (PNL), caffeine (CAF), diclofenac (DCF), clofibric acid ( CLF), ibuprofen ( IBU), carbamazepine ( CBM), paracetamol ( PRC) and triclosan ( TCS)) with high detection frequencies in urban rivers as the target compounds. Based on the detection, the transport-transformation mechanisms (e.g., adsorption, biodegradation and photodegradation) of the target WWMPs were investigated through static shake-flask experiments. The results showed that the main degradation pathway of AZM, CLM and RC was biodegradation in urban rivers, and the removal rates under sterile and aerobic conditions were 90%, 95% and 100%, respectively. Although CBM showed moderate adsorption affinity in the sediment, it was recalcitrant to be hydrolyzed and biodegraded. Adsorption-desorption equilibrium was the reason that led to its stable existence. In the adsorption experiments, it was hard to adsorb four hydrophilic compounds (ATL, STZ, PRC and TMP) on sediment, while for the other nine hydrophobic compounds adsorption affinity mainly depended on the octanol-water partitioning coefficient ( KOW ) . Besides, the photodegradation experiment indicated that direct photodegradation of most target WWMPs hardly occurs in the actual environments, affected by suspended particulates and photosensitizers. TMP, DCF, PNL, CAF and TCS are prone to photodegradation;the degradation rates under the conditions of light and light avoidance were 20% and 10%, 58% and 25%, 22% and 5%, 20% and 2% and 30% and 5%, respectively. This study showed that the WWMPs in urban rivers have obvious degradation effects under the co-action of biodegradation, adsorption and photodegradation.
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