Schets Franciska M, During Marcel, Italiaander Ronald, Heijnen Leo, Rutjes Saskia A, van der Zwaluw Willem K, de Roda Husman Ana Maria
National Institute for Public Health and the Environment (RIVM), Microbiological Laboratory for Health Protection, P.O. Box 1, 3720 BA Bilthoven, the Netherlands.
Water Res. 2005 Nov;39(18):4485-93. doi: 10.1016/j.watres.2005.08.025. Epub 2005 Oct 10.
The microbiological quality of drinking water from 144 private water supplies in the Netherlands was tested and additionally the occurrence of Escherichia coli O157 was examined. Faecal indicators were enumerated by using standard membrane filtration methods. The presence of E. coli O157 was determined using a specific enrichment method. Eleven percent of the samples contained faecal indicators whereas E. coli O157:H7 was isolated from 2.7% of the samples that otherwise met the drinking water standards. The E. coli O157 positive water supplies were located on camp-sites in agricultural areas with large grazer densities. Pulsed field gel electrophoresis (PFGE) analysis suggested that cattle might have been the cause of contamination. Our results indicate that compliance with microbiological quality standards obtained in routine monitoring does not always guarantee the absence of pathogens. The presence of pathogens such as E. coli O157 may suggest possible health consequences; however, a risk assessment process should be performed as the monitoring of both faecal indicator parameters and pathogens do not predict the effect of microbial contamination of drinking water on a population.
对荷兰144个私人供水系统的饮用水微生物质量进行了检测，并额外检测了大肠杆菌O157的存在情况。通过使用标准膜过滤方法对粪便指示菌进行计数。采用特定的富集方法确定大肠杆菌O157的存在。11%的样本含有粪便指示菌，而在其他方面符合饮用水标准的样本中，2.7%分离出了大肠杆菌O157:H7。大肠杆菌O157呈阳性的供水系统位于放牧密度大的农业地区的露营地。脉冲场凝胶电泳（PFGE）分析表明，牛可能是污染的源头。我们的结果表明，常规监测中达到微生物质量标准并不总是能保证没有病原体。大肠杆菌O157等病原体的存在可能意味着存在健康风险；然而，由于对粪便指示菌参数和病原体的监测并不能预测饮用水微生物污染对人群的影响，因此应进行风险评估。
