13种新型极性苯酚类氯/溴代消毒副产物的生成机理

Formation mechanism of 13 new polar phenolic chlorinated and brominated disinfection byproducts in drinking water

近年来,基于超高效液相色谱/电喷雾电离三重四极杆质谱(UPLC/ESI-tq MS)的多反应监测扫描(MRM)、前体离子扫描和子离子扫描技术,研究人员在饮用水中发现了13种新型极性苯酚类氯/溴代消毒副产物(Cl-/Br-DBPs).它们不仅具有比脂肪族消毒副产物更高的细胞毒性、生长发育毒性和生长抑制作用,而且降解后会产生三卤甲烷和卤代乙酸类消毒副产物,因此受到了人们的极大关注.为探究13种新型极性苯酚类Cl-/Br-DBPs在饮用水消毒过程中的生成机理以及更好地控制其生成,本研究以没食子酸为前驱物,在实验室模拟氯和氯胺的消毒过程,通过UPLC/ESI-tq MS MRM方法分析没食子酸和氯/氯胺消毒反应的终产物及部分中间产物,并推测了这13种Cl-/Br-DBPs在氯消毒过程中的反应路径.结果表明,模拟和实际饮用水水源水中均存在没食子酸,且经氯/氯胺消毒后的没食子酸反应液中生成了10种新型极性苯酚类Cl-/Br-DBPs,证明没食子酸是生成13种新型极性苯酚类Cl-/Br-DBPs的前驱物之一.

Recently,13 new polar phenolic chlorinated and brominated disinfection byproducts（ Cl-/Br-DBPs） have been identified in drinking water by using multiple reaction monitoring（ MRM）,precursor ion scan,and product ion scan of ultra-performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry（ UPLC/ESI-tq MS）. The new DBPs have attracted increasing concern since they were proved to have higher cytotoxicity,developmental toxicity,and growth inhibition than aliphatic DBPs,and form trihalomethanes and haloacetic acids via decomposition. In this study,a series of samples were prepared by reacting gallic acid with chlorine/monochloramine in the presence of bromide to simulate chlorinated/chloraminated drinking water samples with gallic acid as carbon source. The reaction products,intermediate compounds,and gallic acid were analyzed using UPLC/ESI-tq MS. Gallic acid was proved to exist in both simulat and real source waters,and 10 new polar phenolic Cl-/Br-DBPs were identified and quantified in the chlorinated/chloramined gallic acid reaction solutions,suggesting that gallic acid is one of the precursors of the 13 new phenolic DBPs.