Environmental health in slum communities : analysis of household water quality in four slum communities in the City of Bhuj, India

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Environmental health in slum communities Analysis of household water quality in four slum communities in the City of Bhuj, India Fiona Wieland, Basel 1 Introduction The environment in which we live greatly affects our health. To stay healthy, the water we drink, the air we breathe and the food we eat must be clean, wholesome and/or free from contamination. A good environment is, thus, most relevant for our well-being. However, especially in slum communities, environmental health conditions are particularly bad. Both the natural and the built environment are not free from undue hazard. In many cases, essential environmental services, such as adequate sanitation facilities, water supply and solid waste management, are not provided to households and communities.
However, the poor are vulnerable not only because of where they live, but also due to the work they do, the greater risks they run and their lower resistance to infections. 1.1 billion people worldwide do not have access to a safe water supply and 2.4 billion lack adequate sanitation World Health Organization 2001: 6). As is illustrated in Fig. 1, many diseases may be linked to an inadequate water and sanitation situation.
Environmental health focuses on all aspects related to health. When poor people get ill, they lose their income and in many cases, also their jobs.
Environmental health interventions, such as improved water supply, drainage and sanitation are known to improve the health situation of poor communities. For the poor, however, health is often only a minor benefit of such improvements. The main benefits frequently are about saving time e.g. from water collection), reducing the burden of daily life, lowering the basic cost of living, supporting the emancipation of women, promoting dignity, self-respect and safety, creating a more pleasant and ordered living space and raising income. Additionally, environmental health can contribute to national and regional education goals: diseases keep children away from school, not only when they are ill themselves, but also when they have to work instead of their ill parents. The lack of environmental services at schools, particularly with regard to sanitation and water supply, is also an important determinant to school registration of girls, especially after puberty Cairncross & Kolsky 2003: 1-3).

Research focus
The article presents results of a sub-project within the research project «GIS-based slum monitoring for mitigating poverty, vulnerability and disease in urban slums» led by the Urban and Regional Studies Unit of the Institute of Geography, University of Basel, Switzerland, and the All IndiaDisaster Mitigation Institute in Ahmedabad AIDMI), India. The study area is built by four selected slum communities in the City of Bhuj, notably Jayprakashnagar, Shantinagar, Bhimraonagar and Mustuffanagar.
The main research objective was to determine key variables affecting the water quality of the surveyed households. These variables may have a demographic, social or financial character or concern environmental services. Thus, attention was paid in particular to the following aspects: -The description of the prevailing water supply, sanitation and hygiene situation within the four surveyed slum communities.
-The creation of maps to show the spatial distribution of the drinking water quality in the four surveyed slums.
-The identification of indicator variables for the water quality and of areas with urgent drinking water problems.
-The specification of the action to be taken and the areas of application. The analyses took place at both the micro and the macro level. Thus, data was evaluated at both household level and slum level. This enabled a clear comparison of the four surveyed slum communities.

Spatial information and questionnaire
In order to create a spatial information basis, the slum areas were systematically mapped inthe field and visually presented using Geographic Information System GIS).

Water analysis
As faecal contamination is often considered a major health riskin association with small-community water supplies, particular attention was given to water quality analysis. Micro-biological analysis of the drinking water was carried out to determine the hygienic quality of the water supply. This examination required the isolation 13).
For membrane filtration, a minimum sample volume of 10 mlis introduced aseptically into a sterile or properly disinfected filtration assembly containing a sterile membrane filter with a nominal pore size of 0.2 or 0.45 Mm. The volume to be filtered strongly depends on the degree of pollution. The World Health Organization WHO) recommends a standard volume of 100 ml in its guidelines for safe drinking water. But, if for example water of a river is examined, a dilution of the sample is meaningful. In surface water in particular, a high degree of pollution can be expected, making countability of bacteria colonies in non-diluted solutions problematic.
By means of vacuum, the sample is drawn through the membrane filter. This allows all indicator organisms to be retained on or within the filter. The filter is then transferred to a suitable selective culture medium in a petri dish. The petri dish is transferred to an incubator set at an appropriate temperature. There it is incubated for a determined time to allow the indicator organisms to mulitply. Thus, visually identifiable and In addition to the analysis of the faecal contamination, the turbidity, the pH value and the amount of chlorine residual were tested. The amount of suspended matter in the water is an important aspect to be taken into consideration when applying disinfectants. High water turbidity could prevent the micro organisms from getting attacked by the disinfecting agent. The acidity of the water pH value), on the other hand, influences the effectiveness of disinfection by chlorine and other chemical solutions. Specifically, pH values above 8 reduce the ability of a chlorine disinfectant to eliminate germs. Where water has been disinfected by chlorine, there should be a small amount of residual chlorine in the water to protect it against recontamination.
If this amount is too high, it could harm the consumer's health. 4 Results and discussion 4.1 Water quality situation at slum level A comparison of the tested water samples by slum community adds a spatial dimension for the large differences in quality.
Although drinking water in the Jaypragashnagar slum community was particularly highly contaminated, overall water quality in Shantinagar was alarming. Such high concentrations of E.coli bacteria can be explained by a very poor quality of water supplies or a lack of sanitary drinking water handling. In fact, it is likely that both of the above apply here. The results show that immediate interventions are necessary in these slum communities.
The water samples from the Bhimraonagar and Mustuffanagar slum communities also indicated a contamination with E.coli bacteria. Although the levels found here are still very harmful for human health,compared to the concentrations found in the other two slums, they were relatively low maps 1-4).
In order to examine whether dependencies between a household's water quality and demographic, social or financial factors exist, water samples from around 100 households spread over the four slum areas were taken and analysed.

Water quality situation at household level
Neither the results of the pH analysis nor the turbidity testing appeared particularly alarming: the pH value of the tested water samples ranged from 6.5-7 pH. These results lie within the normal range for water and thus indicate more or less neutral conditions neither acidic nor alkaline).The turbidity of the tested water samples was light with only five samples showing a turbidity higher than 5 NTU Nephelometric Turbidity Units).
On the other hand, water quality testing revealed greater differences, particularly with regards to the amount of E.coli bacteria in the water Tab. 1). E.coli bacteria per 100 ml, thus making them of «high risk» for human health. 11 households 12.5%) were found to be consuming drinking water with over 1000 E.coli/100 ml veryhigh risk) WorldHealth Organization 1997: 78).
These results show that most of the families living in the four surveyed slum communities daily consume water with a great amount of E.coli bacteria. The presence of these bacteria indicates a faecal contamination of the water. Specific diseases like diarrhoea, cholera and typhoid, which can be transmitted over water are called faecal-oral diseases. They represent the most common water related diseases World Health Organization 2002: 127).

Water treatment methods
In light of the alarming water quality results, water samples were analysed according to undergone purification treatment, if any.
Of 77 households analysed 11 households did not indicate their treatment method), 72.7% appear to filter their drinking water through a piece of cloth before consumption. Only five households 6.5%) boil their water before drinking and 26% of the households do not treat their water at all Tab. 2). A family using this method to «clean» its drinking water may not be sure of drinking safe water after the treatment. Either the method does not effectively rid water of these particular germs or recontamination of water after treatment has to be taken into account.
However, it cannot be taken for granted that 82.7% of the E.coli bacteria pollution came from recontamination by the consumers alone. To argue that recontamination is the main cause would be to imply that all other treatment methods have a similar risk or recontamination is linked to a particular water treatment method. To get a general idea of the effectiveness of other treatment methods, isolated tests were carried out. Thus, in addition to the household water samples taken, specific samples from community wells and hand pumps were collected. From each of these external sources, three water samples were taken. One was tested without treating, the second was treated with Micropur Forte chlorination pill for water treatment) and the last sample was exposed to sunlight by using SODIS, which is a low-cost water treatment method using the solar energy to disinfect microbiologically contaminated raw water Swiss Federal Institute of Aquatic Science andTechnology 2005) Fig. 2).
Compared to the results of cloth filtration,which showed a highly diverging water quality, the treatment by chlorination and SODIS showed satisfying results. Both methods eliminated the existing germs inalltested water samples with an efficiency of 100%. But as thechlorination products are quite expensive, theiramount has to be adapted to the degree of contamination and they leave a bad aftertaste to the water, the SODIS method seems to be the most appropriate method to be used in slum community households. Pet bottles are locally available, the needed insolation is mostly given and water with a high turbidity can be filtered before Fig. 3 On the whole, it appears that a household's water supply and sanitation situation is affected more by financialsecurity than by social environment.The only social factor, which shows a constant trend in relation to tested water quality, is the «number of family members» The more members a family has, the worse the drinking water quality gets. However, this trend depends more on a certain threshold value than minimal differences of one or two family members; when a certain household size is exceeded, the water quality deteriorates. This could be explained by increasing risk of recontamination as the number of family members increases, or by the weaker financial situation of a larger family.
Indeed, the relation between household water quality and total family monthly income appears significant.
In a household with high financial security, the willingness to invest in water supply and sanitation facilities The higher the education level of the family head, the better the awareness of relations between environmental health and personal health. The results show a high coherence between the awareness of these facts and the water quality found in the family Tab. 5).
The better water quality of families with a higher income can therefore be explained by their higher education standard and greater awareness of environmental influences, in addition to a greater willingness Water quality, measured by E.coli per 100 ml to invest in improving their personal water and sanitary situation. Particularly the last aspect has a direct influence on improving a family's health situation.

Implications
The results of the study point out three areas of action and approaches to solutions.

Water supply and sanitation situation improvement
The water supply and sanitation situation in the surveyed slum communities is insufficient. It is therefore unsurprising that the water quality tests showed an insufficient overall drinking water quality in the four surveyed slum communities. Only 31.8% of the tested households could consume their water safely or with low health risks. The remaining households consumed drinking water which was highly contaminated with E.coli bacteria, raising their risk of infection by various diseases. Although the drinking water provided by private taps has a better quality than the water from public wells and hand pumps, it does not satisfy the WHO guidelines for drinking water and should not be consumed untreated. The second area of action concerns education efforts and changes in behavioural patterns. The most direct route to improving environmental health is to improve hygiene in all aspects related to water, food and sanitation. People need to know the relations between environmental health and their personal health conditions. They should be sensitised to disease transmission routes and the way they can prevent their families and themselves from infections. An ideal place to communicate this information and behaviour pattern is at school. If children learn to treat their drinking water and food in a hygienically suitable manner and to wash their hands after defecation, they are likely to continue doing so even when they are adults and they will hopefully pass their knowledge on to their children.
A further possibility of awareness raising is to initiate community workshops to reach the adult population.
5.3 Dissemination of more effective water treatment methods and support of use The third area of action is related to the people's ignorance on how to handle bad drinking water. Even though about 77% of the households treat their drinking water, they do not use effective methods. As the prevailing water and sanitation situation cannot change from one day to the other, better education relating to treatment methods is necessary. To adequately treat their water, the slum dwellers need to know the different treatment methods, the way they work, their advantages and limitations. in the City of Bhuj an effective treatment of their drinking water is essential for their personal health.Application trainings and support during the weeks of application at home may encourage people to keep on treating their drinking water after the initial experimental phase. The water disinfection methods mentioned above may also be taught in school but more effort should be invested into the education of the adult slum dwellers. It is, of course, beneficial when children learn to treat their drinking water as early as possible but parents, and in particular the women, are normallyresponsible for the household's water treatment. Their education, therefore, is an essential factor in the propagation of effective water treatment methods.
Summary: Environmental health in slum communities.
Analysis of household water quality in four slum communities in the City of Bhuj, India The main focus of this study is on water quality in four slum communities in the City of Bhuj, India. In order to determine key variables affecting water quality in surveyed households, the interrelation between household water quality, environmental services, and demographic, social and financial factors was examined. The data used in this study draws on a household survey and the analysis of water samples collected within the targeted slum communities. As faecal contamination of drinking water is a major health risk in smallcommunity supplies, water samples were tested for E.coli bacteria using the membrane-filter method. In a next step, the efficiency of three water treatment methods filtration through cloth, chlorination and solar disinfection -was tested. Considering various factors, solar disinfection is identified to be the most appropriate method for households in most slum areas. The analysis shows that the water supply and sanitation situation of a household has an effect on that household's drinking water quality. Personal endeavours to Comme le risque principal pour la santé provient de la pollution de l'eau par des matières fécales, des bactéries E.coli ont tout d'abord été recherchées dans les prélèvements d'eau analysés, en utilisant la méthode des filtres à membranes. La fiabilité de trois méthodes de purification de l'eau a ensuite été testée: lafiltration par des textiles, la chloration et la désinfection solaire.