Yamamoto Kohji, Mori Yoshiaki
Osaka City Institute of Public Health and Environmental Sciences, Osaka 536-0026, Japan.
Bull Environ Contam Toxicol. 2009 Nov;83(5):674-6. doi: 10.1007/s00128-009-9776-7. Epub 2009 May 28.
Dramatic changes in trihalomethanes of tap water caused by decreasing the chlorine dose from to break-point to zero at a pre-chlorination could be found during several years from starting the advanced treatment in Osaka Prefectural water utilities (from 1998 to 2002). In 1998 (break-point chlorination), chloroform was predominant (an average of 14.3 microg/L) and bromodichloromethane (5.96 microg/L), dibromochloromethane (4.19 microg/L) and bromoform (1.06 microg/L) were in the decreasing order. In contrast, in 1999 (chloramination), dibromochloromethane and bromodichloromethane were abundant trihalomethanes (6.61 and 5.72 microg/L) and followed by chloroform (4.14 microg/L) and bromoform (1.41 microg/L). Trihalomethane distribution in 2002 (non-chlorination) was almost the same as that in 1999.
在大阪府自来水公司开始深度处理后的几年间（1998年至2002年），可以发现预氯化时将氯剂量从折点降至零会导致自来水中三卤甲烷发生显著变化。1998年（折点氯化），氯仿占主导（平均14.3微克/升），溴二氯甲烷（5.96微克/升）、二溴一氯甲烷（4.19微克/升）和溴仿（1.06微克/升）依次减少。相比之下，1999年（氯胺消毒），二溴一氯甲烷和溴二氯甲烷是主要的三卤甲烷（6.61和5.72微克/升），其次是氯仿（4.14微克/升）和溴仿（1.41微克/升）。2002年（无氯化）的三卤甲烷分布与1999年几乎相同。
