Grandjean D, Fass S, Tozza D, Cavard J, Lahoussine V, Saby S, Guilloteau H, Block J-C
LCPME, UMR 7564 CNRS-UHP, Faculté de Pharmacie, Pôle de l'Eau, 15 avenue du Charmois, 54500 Vandoeuvre-lès-Nancy, France.
Water Res. 2005 May;39(9):1878-86. doi: 10.1016/j.watres.2005.03.012. Epub 2005 Apr 25.
The culturability of Escherichia coli in undersaturated drinking water with respect to CaCO3 (corrosive water) or in oversaturated water (non-corrosive water) was tested in different reactors: glass flasks (batch, "non-reactive" wall); glass reactors (chemostat, "non-reactive" wall) versus a corroded cast iron Propella reactor (chemostat, "reactive" wall) and a 15-year-old distribution system pilot (chemostat, "reactive" wall with 1% corroded cast iron and 99% cement-lined cast iron). The E. coli in E. coli-spiked drinking water was not able to maintain its culturability and colonize the experimental systems. It appears from our results that the optimal pH for maintaining E. coli culturability was around 8.2 or higher. However, in reactors with a reactive wall (corroded cast iron), the decline in E. coli culturability was slower when the pH was adjusted to 7.9 or 7.7 (i.e. a reactor fed with corrosive water; pH<pHs) than in non-corrosive water (pH 8.64 or 8.24; pH>pHs). We tentatively deduce that corrosion products coming from chemical reactions driven by corrosive waters on the pipe wall improve E. coli culturability.
在不同的反应器中测试了大肠杆菌在相对于碳酸钙不饱和的饮用水（腐蚀性水）或过饱和水（非腐蚀性水）中的可培养性：玻璃烧瓶（间歇式，“非反应性”壁）；玻璃反应器（恒化器，“非反应性”壁）与腐蚀的铸铁螺旋桨反应器（恒化器，“反应性”壁）以及一个有15年历史的配水系统试验装置（恒化器，“反应性”壁，含1%腐蚀铸铁和99%水泥衬里铸铁）。接种了大肠杆菌的饮用水中的大肠杆菌无法维持其可培养性并在实验系统中定殖。从我们的结果来看，维持大肠杆菌可培养性的最佳pH值约为8.2或更高。然而，在具有反应性壁（腐蚀铸铁）的反应器中，当pH值调整到7.9或7.7时（即一个用腐蚀性水进料的反应器；pH<pHs），大肠杆菌可培养性的下降比在非腐蚀性水（pH 8.64或8.24；pH>pHs）中更慢。我们初步推断，由腐蚀性水在管壁上引发的化学反应产生的腐蚀产物提高了大肠杆菌的可培养性。
