British Geological Survey, Maclean Building, Wallingford, OX10 8BB, UK.
British Geological Survey, Maclean Building, Wallingford, OX10 8BB, UK.
Water Res. 2018 Jun 15;137:301-309. doi: 10.1016/j.watres.2018.03.001. Epub 2018 Mar 3.
We assessed the utility of online fluorescence spectroscopy for the real-time evaluation of the microbial quality of untreated drinking water. Online fluorimeters were installed on the raw water intake at four groundwater-derived UK public water supplies alongside existing turbidity sensors that are used to forewarn of the presence of microbial contamination in the water industry. The fluorimeters targeted fluorescent dissolved organic matter (DOM) peaks at excitation/emission wavelengths of 280/365 nm (tryptophan-like fluorescence, TLF) and 280/450 nm (humic-like fluorescence, HLF). Discrete samples were collected for Escherichia coli, total bacterial cell counts by flow cytometry, and laboratory-based fluorescence and absorbance. Both TLF and HLF were strongly correlated with E. coli (ρ = 0.71-0.77) and total bacterial cell concentrations (ρ = 0.73-0.76), whereas the correlations between turbidity and E. coli (ρ = 0.48) and total bacterial cell counts (ρ = 0.40) were much weaker. No clear TLF peak was observed at the sites and all apparent TLF was considered to be optical bleed-through from the neighbouring HLF peak. Therefore, a HLF fluorimeter alone would be sufficient to evaluate the microbial water quality at these sources. Fluorescent DOM was also influenced by site operations such as pump start-up and the precipitation of cations on the sensor windows. Online fluorescent DOM sensors are a better indicator of the microbial quality of untreated drinking water than turbidity and they have wide-ranging potential applications within the water industry.
我们评估了在线荧光光谱法在实时评估未处理饮用水微生物质量方面的效用。在英国四个地下水供水系统的原水入口处安装了在线荧光计，旁边是现有的浊度传感器，用于预警水中微生物污染的存在。荧光计针对激发/发射波长为 280/365nm（色氨酸样荧光，TLF）和 280/450nm（腐殖酸样荧光，HLF）的荧光溶解有机物（DOM）峰。采集了离散水样，用于检测大肠杆菌、流式细胞术测定的总细菌细胞计数以及实验室荧光和吸光度。TLF 和 HLF 均与大肠杆菌（ρ=0.71-0.77）和总细菌细胞浓度（ρ=0.73-0.76）呈强相关，而浊度与大肠杆菌（ρ=0.48）和总细菌细胞计数（ρ=0.40）之间的相关性较弱。在这些站点没有观察到明显的 TLF 峰，所有明显的 TLF 都被认为是来自相邻 HLF 峰的光学漏通。因此，单独使用 HLF 荧光计就足以评估这些水源的微生物水质。荧光 DOM 还受到站点操作的影响，例如泵启动和传感器窗口上阳离子的沉淀。在线荧光 DOM 传感器是未处理饮用水微生物质量的更好指标，它们在水工业中有广泛的潜在应用。
