某自来水厂水源多环芳烃污染分析

Analysis of contamination from polycyclic aromatic hydrocarbons (PAHs) in source water of municipal waterworks in south of China

采用 Oasis HLB柱固相萃取前处理和气相色谱 /质谱联用仪的分析方法 ,研究了中国南方某城市自来水厂的水源中多环芳烃的污染分布与来源。结果表明 ,该地区水域中存在多环芳烃的轻度污染。多环芳烃的分布随季节有一定变化 ,夏季丰水期 1 6种检测多环芳烃总浓度约是春季的两倍。多环芳烃污染以二、三环芳烃为主 ,主要由于石油排污造成 ,但仍有部分来源于不完全燃烧热解的五环芳烃检出。 5个采样点样品中多环芳烃总量均未超出相关标准 ,但春季采样苯并 [a]芘浓度超出我国饮用水源标准 。

The authors of this paper have made an analysis of the distribution and origin of polycyclic aromatic hydrocarbons (PAHs) in the water source of a municipal waterworks in China's south. In so doing, we collected and chose water samples at five sites along a river for drinking water source. After 4 L volume of water had passed through the Oasis HLB solid-phase extraction cartridges, the cartridges were returned to the laboratory and eluted with 10 mL aliquot of dichloromethane for each one. The eluates were cleaned up with silica gel/aluminum oxide composite chromatographic columns and analyzed by GC/MSD. As a result, satisfactory recovery efficiency of 89.6%±18.4% was obtained with our method in the quality control experiments, for 16 PAHs which were listed as priority pollutants by US Environmental Protection Agency (EPA). 12 PAHs i.e. 2-ring aromatic carbons Naphthalene; 3-ring aromatic carbons Acenaphthylene, Acenaphthene, Fluorene, Phenanthrene and Anthracene; 4-ring aromatic carbons Fluoranthene, Pyrene, Chrysene and Benzo(a)anthracene; 5-ring aromatic carbons Benzo(b)fluoranthene, Benzo(k)fluoranthene and Benzo(a)pyrene. The experimental results of ours indicate that there was a low-grade contamination from PAHs in the water bodies of this area. The distribution of PAHs has revealed a seasonality, by which the combined concentration of 16 PAHs (∑PAHs) determined in summer was considered as high water period, was almost as twice as that in spring considered as low water season. These PAHs had a mixed origin for preliminary estimate, with a main contribution of petrogenic origin and a low contribution of pyrogenic origin. ∑PAHs in water samples of five sites were within the limits of relevant standards, while the concentration of Benzo(a)pyrene sampled in spring exceeded the limit of standard for source water of drinking water in Environmental Quality Standards for Surface Water in China (GB 3838-2002). Benzo(a)pyrene should be one point of exertion of monitoring and control carried in the next phase of work in source water of drinking water in the south of China.