Institut de Veille Sanitaire, 14 rue de Val d'Osne, 94415, Saint-Maurice cedex, France.
J Water Health. 2010 Mar;8(1):20-34. doi: 10.2166/wh.2009.043.
This geographical study aimed to show natural or water-processing-related factors of faecal contamination incidents (FCIs) of drinking water in continental France. We defined a FCI as the occurrence of at least 20 colony-forming Escherichia coli or enterococci among all the 100 mL samples collected for regulatory purpose within one day from a given drinking water supply zone (SZ). We explored correlations between the standardized number of FCIs per département (N_Pols) and various indicators related to weather, land cover, topography, geology and water management for three SZ size sub-classes. In 2003-2004, 2,739 FCIs occurred in SZs supplying fewer than 2,000 people, mainly with simply disinfected groundwater. N_Pols correlates with four covariates: (1) precipitation; (2) the extension of the karst outcrops; (3) the extent of disinfection; and (4) catchment protection. One hundred millimetres of yearly excess in precipitation increases the pollution risk by 28-37%, depending on the sub-class. A 10% extension of the karst areas, a 10% increase of unprotected resources, or of SZs with no disinfection, could entail a higher risk of FCI by about 10%. The correlations are reproducible over the three sub-classes and corroborate expert appraisals. These results encourage the ongoing effort to generalize disinfection and catchment protection.
本地理研究旨在展示法国本土饮用水粪污染事件（FCIs）的自然或水加工相关因素。我们将 FCI 定义为在一天内从给定的饮用水供应区（SZ）中收集的所有 100 毫升样品中至少有 20 个菌落形成大肠杆菌或肠球菌。我们探索了在三个 SZ 大小子类中，FCIs 标准化数量（N_Pols）与各种与天气、土地覆盖、地形、地质和水管理相关的指标之间的相关性。在 2003-2004 年，有 2739 起 FCI 发生在供应人数少于 2000 人的 SZ 中，主要是经过简单消毒的地下水。N_Pols 与四个协变量相关：（1）降水；（2）喀斯特露头的延伸；（3）消毒的程度；（4）集水区的保护。每年降水量增加 100 毫米，污染风险会增加 28-37%，具体取决于子类。喀斯特地区每增加 10%，未受保护的资源或未消毒的 SZ 每增加 10%，FCIs 的风险就会增加约 10%。这些相关性在三个子类中具有再现性，并证实了专家的评估。这些结果鼓励继续努力推广消毒和集水区保护。
