Stojek Nimfa Maria, Dutkiewicz Jacek
Department of Water and Soil Safety, Institute of Rural Health, Lublin, Poland.
Ann Agric Environ Med. 2011;18(2):330-4.
A total of 320 potable water samples were collected from various rural and urban sources located in the Lublin region of eastern Poland. They comprised: 55 samples of treated (chlorinated) tap water from rural dwellings distributed by the municipal water supply system (MWSS), 111 samples of treated tap water from urban dwellings distributed by the MWSS, 45 samples of untreated well water from household wells and 109 samples from private water supply systems (PWSS) distributing untreated well water. Water samples were examined for the presence and species composition of Legionella, Yersinia, Gram-negative bacteria belonging to family Enterobacteriaceae (GNB-E) and Gram-negative bacteria not belonging to the family Enterobacteriaceae (GNB-NE), by filtering through cellulose filters and culture on respectively GVPC, CIN, EMB and tryptic soya agar media. The occurrence of Legionella in the samples taken from the outlets of the urban MWSS was high (77.5%), and significantly greater compared to frequencies noted in rural MWSS (7.3%), and samples of well water from household wells (28.9%) and PWSS (13.8%) (p<0.001). Strains L. pneumophila serogroups 2-14, L. pneumophila serogroup 1 and Legionella spp. (species other than L. pneumophila) formed respectively 64.3%, 17.5%, and 18.2% of total isolates from urban MWSS, 100%, 0, and 0 of those from rural MWSS, 69.2%, 7.7%, and 23.1% of those from household wells, and 66.7%, 0, and 33.3% of those from PWSS. The concentration of Legionella strains in the positive samples from urban MWSS exceeded the threshold limit value of 100 cfu/100 ml in 86.1%, while in the other sources this value was not exceeded. No Yersinia strains were isolated from the examined water samples. Altogether 8 species or genera of Gram-negative bacteria belonging to Enterobacteriaceae family (GNB-E) and 10 species or genera of Gram-negative bacteria not belonging to the Enterobacteriaceae family (GNB-NE) were found in the examined samples. In the MWSS samples, an inverse relationship was found between Legionella and GNB-E and the numbers of Enterobacter spp. and Serratia spp. strains were significantly more common in the samples without Legionella. By contrast, in the PWSS samples, the numbers of Enterobacter spp., Klebsiella spp. and Salmonella spp. were distinctly and significantly greater (p<0.01-p<0.001) in the samples containing Legionella. Among GNB-NE, Pseudomonas aeruginosa strains occurred significantly more frequently in samples containing Legionella (for MWSS and well water separately p<0.05, for total samples p<0.001). Similarly, strains of Flavobacterium breve and Xanthomonas spp. occurred significantly more often in the samples with Legionella, while the numbers of Aeromonas spp. and Vibrio spp. strains were significantly greater in the samples not containing Legionella. In conclusion, a health risk could be associated with exposure to the water from urban MWSS because of the high prevalence and concentration of Legionella, and with exposure to well water from PWSS because of the correlation of occurrence of Legionella and potentially pathogenic Enterobacteriaceae strains, and the possibility of synergistic eff ects. The adverse eff ects could be also due to the significant correlation of Legionella and Pseudomonas aeruginosa that occured in water from various sources.
共采集了320份饮用水样本，这些样本来自波兰东部卢布林地区的不同城乡水源。它们包括：55份由市政供水系统（MWSS）供应的农村住宅经处理（氯化）的自来水样本，111份由MWSS供应的城市住宅经处理的自来水样本，45份来自家庭水井的未处理井水样本，以及109份来自供应未处理井水的私人供水系统（PWSS）的样本。通过纤维素滤膜过滤，并分别在GVPC、CIN、EMB和胰蛋白胨大豆琼脂培养基上培养，对水样进行嗜肺军团菌、耶尔森菌、肠杆菌科革兰氏阴性菌（GNB - E）和非肠杆菌科革兰氏阴性菌（GNB - NE）的存在及种类组成检测。城市MWSS出水口采集的样本中嗜肺军团菌的检出率很高（77.5%），与农村MWSS（7.3%）、家庭水井（28.9%）和PWSS（13.8%）的检出频率相比显著更高（p<0.001）。嗜肺军团菌血清型2 - 14菌株、嗜肺军团菌血清型1菌株和嗜肺军团菌属（非嗜肺军团菌的其他种类）分别占城市MWSS分离菌株总数的64.3%、17.5%和18.2%，农村MWSS的分别为100%、0和0，家庭水井的分别为69.2%、7.7%和23.1%，PWSS的分别为66.7%、0和33.3%。城市MWSS阳性样本中嗜肺军团菌菌株浓度在86.1%的样本中超过了100 cfu/100 ml的阈值，而其他水源未超过该值。在所检测的水样中未分离出耶尔森菌菌株。在所检测的样本中共发现了8种属于肠杆菌科的革兰氏阴性菌（GNB - E）和10种不属于肠杆菌科的革兰氏阴性菌（GNB - NE）。在MWSS样本中，发现嗜肺军团菌与GNB - E以及肠杆菌属和沙雷氏菌属菌株数量之间呈负相关，在无嗜肺军团菌的样本中肠杆菌属和沙雷氏菌属菌株更为常见。相比之下，在PWSS样本中，含有嗜肺军团菌的样本中肠杆菌属、克雷伯菌属和沙门氏菌属的数量明显且显著更多（p<0.01 - p<0.001）。在GNB - NE中，铜绿假单胞菌菌株在含有嗜肺军团菌的样本中出现频率显著更高（MWSS和井水样本分别为p<0.05，总样本为p<0.001）。同样，短黄杆菌和黄单胞菌属菌株在含有嗜肺军团菌的样本中出现频率显著更高，而气单胞菌属和弧菌属菌株数量在不含嗜肺军团菌的样本中显著更多。总之，由于嗜肺军团菌的高流行率和浓度，接触城市MWSS的水可能存在健康风险，而由于嗜肺军团菌与潜在致病性肠杆菌科菌株的相关性以及协同效应的可能性，接触PWSS的井水也可能存在健康风险。各种水源水中嗜肺军团菌与铜绿假单胞菌的显著相关性也可能产生不良影响。
