Quality of water the slum dwellers use: The case of a Kenyan slum
Quality of water the slum dwellers use: The case of a Kenyan slum
复制标题
DOI：
10.1007/s11524-007-9199-x
复制
发表时间：
2007-11-01
影响因子：
6.6
通讯作者：
Ngindu, Augustine M.
中科院分区：
文献类型：
--
作者：
Kimani-Murage, Elizabeth Wambui;Ngindu, Augustine M.
在经济困难的背景下，由于快速城市化，撒哈拉以南非洲的大多数城市居民生活在贫民窟中，其特点往往是缺乏水和排污等基本服务。因此，城市穷人经常使用廉价的坑式厕所，同时可能从附近的水井取水。贫民窟的过度拥挤限制了井和坑式厕所之间的适当距离，从而使微生物从厕所迁移到水源。这些过度拥挤的贫民窟的卫生做法也很差，导致这些水井受到污染。这项研究试图评估肯尼亚城市贫民窟居民的卫生做法和他们家庭水源的粪便污染。这项横断面研究涉及来自肯尼亚兰加斯贫民窟的192名受访者。从受访者使用的水源采集了40个水样，用于进行大肠菌群实验室分析。在这40个样本中，31个来自浅井，4个来自深井，5个来自水龙头。采用多管发酵技术对水中的大肠菌群进行了计数。研究发现，兰加斯贫民窟的大多数人(91%)使用水井作为主要的生活用水来源，而其余的人使用自来水。虽然大多数人使用坑式厕所来处理排泄物，但相当大比例(30%)的儿童在露天场地排泄物。据估计，坑式厕所与井之间的距离一般较短，约40%的坑式厕所距离井不到15米。主要生活水源地被发现高度污染粪便。100%的浅井水样中发现总大肠菌群，而97%的浅井水样耐热大肠菌群呈阳性。来自深井的四个样本中有三个样本的总大肠菌群呈阳性，而四个样本中的两个样本的耐热大肠菌群呈阳性。来自水龙头的样本中，没有一个样本的总大肠菌群或耐热大肠菌群呈阳性。由于水中耐热大肠菌群的存在表明粪便受到污染，井和坑式厕所之间的距离很近，因此研究表明，坑式厕所是含有粪便物质的井的主要污染源。然而，降雨期间通过地表径流造成的污染也是合理的，因为不分青红皂白地处理排泄物也很常见，特别是儿童的排泄物。由于粪便污染，水中存在疾病病原体的可能性很高；因此，兰加斯井水可能不适合人类饮用。为了解决这个问题，建议在社区或家庭一级对水进行处理，并在卫生实践中强化行为改变。应努力向这一社区和撒哈拉以南非洲其他无法获得自来水的贫民窟提供受管制的自来水。
As a result of rapid urbanization in a context of economic constraints, the majority of urban residents in sub-Saharan Africa live in slums often characterized by a lack of basic services such as water and sewerage. Consequently, the urban poor often use inexpensive pit latrines and at the same time may draw domestic water from nearby wells. Overcrowding in slums limits the adequate distance between wells and pit latrines so that micro-organisms migrate from latrines to water sources. Sanitary practices in these overcrowded slums are also poor, leading to contamination of these wells. This study sought to assess sanitary practices of residents of a Kenyan urban slum and fecal contamination of their domestic water sources. This cross-sectional study involved 192 respondents from Langas slum, Kenya. Forty water samples were collected from the water sources used by the respondents for laboratory analysis of coliforms. Of these 40 samples, 31 were from shallow wells, four from deep wells, and five from taps. Multiple-tube fermentation technique was used to enumerate coli form bacteria in water. The study found that most people (91%) in the Langas slum used wells as the main source of domestic water, whereas the rest used tap water. Whereas most people used pit latrines for excreta disposal, a substantial percentage (30%) of children excreted in the open field. The estimated distance between the pit latrines and the wells was generally short with about 40% of the pit latrines being less than 15 m from the wells. The main domestic water sources were found to be highly contaminated with fecal matter. Total coliforms were found in 100% of water samples from shallow wells, while 97% of these samples from shallow wells were positive for thermotolerant coliforms. Three out of the four samples from deep wells were positive for total coliforms, while two of the four samples were positive for thermotolerant coliforms. None of the samples from taps were positive for either total or thermotolerant coliforms. Because the presence of thermotolerant coliforms in water indicates fecal contamination, facilitated by the proximity between the wells and pit latrines, the study suggests that the pit latrines were a major source of contamination of the wells with fecal matter. However, contamination through surface runoff during rains is also plausible as indiscriminate excreta disposal particularly by children was also common. Owing to the fecal contamination, there is a high possibility of the presence of disease pathogens in the water; thus, the water from the wells in Langas may not be suitable for human consumption. To address this problem, treatment of the water at community or household level and intensive behavioral change in sanitary practices are recommended. Efforts should be made to provide regulated tap water to this community and to other slums in sub-Saharan Africa where tap water is not accessible.