北京自备井水源内毒素污染及与其他水质参数的相关分析

本研究采集驻京部队14个自备井水源样品,采用动态浊度东方鲎试验定量检测内毒素活性,同时检测了细菌总数(流式细胞术法)、异养菌平板计数(HPC)、菌落总数(平板法)、总大肠菌群、颗粒物特征、浊度、溶解性有机碳(DOC)和UV254值,比较了内毒素与这些水质参数的相关性.结果表明自备井水源的总内毒素活性为0.15~13.20 EU·m L~(-1),其中游离态内毒素活性为0.10~5.29 EU·m L~(~(-1)),结合态内毒素活性为0.01~8.60 EU·m L~(-1).对于内毒素污染较严重的自备井水源来说,结合态内毒素所占比例明显高于游离态内毒素.总内毒素与其他水质参数关联顺序为细菌总数(流式细胞术法)(r=0.88)HPC(r=0.79)DOC(r=0.77)UV254(r=0.57)总大肠菌群(r=0.50)菌落总数-平板法(r=0.49)=浊度(r=0.49)颗粒物总数(r=0.41).结合态内毒素与其他水质参数关联顺序为细菌总数-流式细胞术法(r=0.81)HPC(r=0.66)总大肠菌群(r=0.65)浊度(r=0.62)颗粒物总数(r=0.58)菌落总数(平板法)(r=0.22).游离态内毒素与水中DOC、UV254的相关系数r分别为0.58和0.26,结果表明游离态内毒素与水中DOC的相关性较大,与UV254相关性很小.

Endotoxin Contamination and Correlation with Other Water Quality Parameters of Groundwater from Self-Contained Wells in Beijing

A survey of endotoxin activity in groundwater from 14 self-contained wells in PLA units stationed in Beijing was conducted by the kinetic-turbid assay of Tachypleus Amebocyte Lysate (TAL). Bacteriological parameters, including total cell counts detected by flow cytometry, heterotrophic plate counts (HPC), standard plate counts and total coliforms were analyzed. Additionally, suspended particles, turbidity, dissolved organic carbon (DOC), and UV₂₅₄ were investigated. Total endotoxin activities ranged from 0.15 to 13.20 EU ·mL^-1, free endotoxin activities ranged from 0.10 to 5.29 EU ·mL^-1 and bound endotoxin activities ranged from 0.01 to 8.60 EU ·mL^-1. Most of the endotoxins in heavily contaminated groundwater existed as bound endotoxins. As for total endotoxins, the sequence of correlation coefficients with other parameters was total cell counts (r=0.88)>HPC (r=0.79)>DOC (r=0.77)>UV₂₅₄ (r=0.57)>total coliforms (r=0.50)>standard plate counts (r=0.49)=turbidity (r=0.49)>total particles (r=0.41). The sequence of correlations of the bound endotoxins with other parameters was total cell counts (r=0.81)>HPC (r=0.66)>total coliforms (r=0.65)>turbidity (r=0.62)>total particles (r=0.58)>standard plate counts (r=0.22). Free endotoxins were correlated with DOC and UV₂₅₄, r=0.58 and 0.26, respectively. Result showed free endotoxins had a higher correlation with DOC, and a lower correlation with UV₂₅₄.