Disinfection by-products ( DBPs) , caused by free chlorine disinfection, are considered to be a serious threat to human health, catching more attention in recent years. Samples were selected from water utilities in Guangzhou, water sources, water treatment technology and indices of acids ( HAAs) in main DBPs were investigated. Results show that in the city the five HAAs concentrations ( HAA5) were 5. 91~45. 75μg·L-1 and the concentration of each compound of HAAs, fitting drink-ing water quality standards. Toxicity the four common HAAs, including dichloroacetic acid ( DCAA) , trichloro acetic acid ( TCAA) , monobromoacetic acid ( MBAA) and dibromoacetic acid ( DBAA) are 184. 07 μg· L-1 , 193. 57 μg · L-1 , 13. 47 mg · L-1 and 15. 00 mg · L-1 . Further, DCAA and TCAA were selected as target pollutants to discuss the degradation of HAAs by Fenton oxidation. Effects of Fenton reagent dosage, initial pH, the initial concentration of simulated water and reaction time on removal efficiencies of HAAs were investigated. The best conditions were confirmed as:H2 O2 concentration of 0. 4 mmol·L-1 , Fe2+concentration of 0. 04 mmol·L-1 , reaction time of 20 min and initial pH of 3. 6. Under the conditions, the degradation efficiency of DCAA and TCAA with an initial concentration of 100 μg·L-1 were 69. 28% and 71. 4%.%以2012年4月初与5月初所采集的广州市自来水管网水样为样本, 通过实验手段分析广州市市政供水中的水源、 管网水等供水水质情况, 对饮用水中卤乙酸浓度进行监测, 结果表明饮用水中总卤乙酸范围在5. 91~45. 75 μg·L-1 , 符合美国EPA环保署对总卤乙酸含量的控制标准, 其中二氯乙酸浓度范围为0. 88 ~16. 69 μg · L-1 , 三氯乙酸浓度范围为3. 72 ~27. 00 μg·L-1, 均符合 《生活饮用水卫生标准》 (GB5749—2006) 对其含量的限制. 对二氯乙酸、 三氯乙酸、 一溴乙酸、 二溴乙酸进行毒性检测中, 测出这4种物质的细菌半致死效应浓度分别为184. 07 μg·L-1、 193. 57 μg·L-1、 13. 47 mg·L-1、 15. 00 mg·L-1. 以二氯乙酸、三氯乙酸为代表物质, 用Fenton试剂氧化法降解模拟水样, 利用气相色谱法测定降解后的卤乙酸浓度, 考察了Fenton试剂用量、 pH值、 模拟水样初始浓度和反应时间对卤乙酸降解效果的影响. 结果表明, 100 μg·L-1的100 mL二氯乙酸、 三氯乙酸模拟水样中投加0. 4 mmol· L-1 H2 O2 溶液及0. 04 mmol·L-1 Fe2+溶液, 反应时间为20 min, 初始pH值为3. 6, 为Fenton试剂氧化法降解二氯乙酸、 三氯乙酸的最佳条件, 降解率分别为69. 28%和71. 4%.
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