飲水機水中總三鹵甲烷之研究

A Study on Trihalomethanes in Drinking Fountain Water

郭錦堂(Ching-Tang Kuo) ； 黃惠慈(Hui-Tzu Huang)

《環境保護》 30卷2期 (2007/12) Pp. 105-113

https://doi.org/10.30017/EP.200712.0005

摘要

日常用水從水源發源地到淨水廠過程中，難免會受有機污染物影響，所以淨水廠為了供應衛生、安全的自來水，會在自來水中以加氯方式來消毒。而在加氯消毒時，原水中如含有有機污染物，即會衍生三鹵甲烷副產物。這些含氯副產物在水中若是含量過高，會對人體造成肝毒、腎毒外，更會引起膀胱癌等病症。因此飲用水中三鹵甲烷含量是影響人體健康的重要因素。本研究採用頂空萃取法，再利用固相微萃取法(SPME)、配合氣相層析儀－電子捕獲偵測器(GC-ECD)，分析中台灣某大學校內裡四種不同牌子的飲水機水中總三鹵甲烷的濃度。SPME吸附最佳檢測條件：吸附溫度60℃、吸附時間10分鐘、脫附溫度150℃、脫附10分鐘。四種分析物標準品，所得到的線性相關係數均在0.996以上。儀器的偵測極限(LOQ)：氯仿、一溴二氯甲烷、二溴一氯甲烷、溴仿四種化合物皆為0.05ppb。再現性測試均在9.81%以下之良好結果。結果顯示四品牌的飲水機，以D飲水機對總三鹵甲烷去除效果最好。在飲用水中，氯仿之偵測率和濃度都明顯高於其他三種，而溴仿則幾乎都未被檢測出。經過評估計算後，其致癌風險值。教職人員、一般大學生及醫學系學生分別為9.72×10^(-6)、1.17×10^(-6)；及2.05×10^(-6)。有經過5μm過濾材質之水質中總三鹵甲烷的含量，比無過濾材質之水質少，可能是過濾材質具有吸附能力，未來可針對材質做史進一步探討。

關鍵字

三鹵甲烷 ； 固相微萃取法SPME ； 氣相層析儀－電子捕獲偵測器GC-ECD ； 致癌風險

並列摘要

Objectives: Chlorination may convent organic pollutants in the water into trihalomethanes and the other halo organic by products during the treatment process. It is widely well known that trihalomethanes one toxicants for the human body, especially for the liver and the kidney, and causing bladder cancer as well. Therefore, it is important to measure the amount of trihalomethanes in drinking water that may affect human health.
Methods: In this study, we used head-space extraction method followed by solid phase microextraction (SPME) to determine the total concentration of trihalomethanes (including chloroform, bromodichloromethane, dibromochloro-methane, and bromoform) in the water samples taken from drinking fountains of four different brands, A, B, C and D, at an university in central Tainan. By using SPME, the optimized detecting conditions were 10 minutes of extraction at 60℃ for the absorption process, and 10 minutes at 150℃ for the desorption process. The coefficients of correlation of the calibration curves for the four chemicals were all above 0.996. In addition, the limit of quantification (LOQ) was above 0.05 ppb. The reproducibility was under 9.8ln,
Results: The results showed that brand D drinking fountain equips with titter of 5μm size had the best removal efficience for total trihalomethanes. Among the four tested chemicals, chloroform had the highest mean concentration, while bromoform could be hardly detected in all samples. When we classified people at Otis university into 3 groups. namely teaching faculty, non-medical students (4 years), and medical students (7 years), their estimated cancer risks were 9.72×10^(-6), 1.17×10^(-6), and 2.05×10^(-6) respectively.
Conclusions: The amount of total trihalomethanes in water can be reduced by filtration. The absorption ability of filter material deserves further research.

並列關鍵字

trihalomethanes ； SPME ； GC-ECD ； cancer risk