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1.
In Western-Europe, agricultural practices have contributed to environmental problems such as eutrophication of surface and ground water, flooding, drought and desiccation of surrounding natural habitats. Solutions that reduce the impact of these problems are urgently needed. Common reed (Phragmites australis) is capable of sanitizing surface water and may function as green energy source because of its high productivity. Here, the results of an experiment in a constructed wetland in the Netherlands are presented where two different sanitation treatments were compared. Depending on the residence time and volume per unit area, reed is capable to reduce the total amount of nitrogen in the water with average efficiencies from 32 to 47% and the total amount of phosphorous with 27–45%. Although biomass production still varies largely between different parts of the constructed wetland, a rapid increase in biomass was observed since planting. Constructed wetlands with reed provide opportunities to improve water quality and reed produces enough biomass to serve as green energy source. Moreover, these wetlands also function as a flood water reservoir and are possibly advantageous for biodiversity. The optimal moment of reed harvesting depends on the goal of the owner. This moment should be chosen wisely, as it may have consequences for reed filter regeneration, biomass production, biodiversity, methane emission and water sanitation efficiency.  相似文献   

2.
Close to 100 million Indonesians lack access to improved sanitation, while 33 million live without improved drinking water. Indonesia is home to the second largest number of open defecators in the world, behind India. Repeated exposure to fecal pathogens, especially common in areas where open defecation is practiced, can cause poor absorption and nutrient loss through diarrhea and poor gut function, leading to undernutrition, growth stunting and irreversible impairment of health, development, learning and earnings – the effects of which outlast a lifetime. Using data from a sample of over six thousand children in the Indonesia Family Life Survey (IFLS), a household socioeconomic panel representative of over 80 percent of the Indonesian population, we examine the relationship between poor household and community water and sanitation services and childhood stunting and cognitive development. We find that children living in households that have access to improved sanitation when they are under 2 years of age are approximately 5 percentage points less likely to end up being stunted. Community rates of sanitation are also important. Children living in open defecation free communities during this critical development window are more than 10 percentage points less likely to be stunted, than children in communities where all other households defecate in the open. Further, cognitive test scores are adversely affected by open defecation. These findings suggest that owning a toilet and living in a community where most of one’s neighbors own a toilet are important drivers of child growth and development.  相似文献   

3.
Access to proper sanitation is still elusive in many parts of Africa. While significant improvement in global sanitation has been realised, the sanitation situation in Africa is still appalling with almost 20 % of the population reported to still practice open defecation in Sub Saharan Africa. The impacts of poor sanitation systems range from negatively impacting natural resources water quality, to causing health risks to the populations involved. Obviously, the current sanitation systems have gaps and can barely help the situation, which points to the necessity of a paradigm shift in the wastewater management to include interventions that would make proper sanitation achievable for all. Such interventions include decentralisation and resource recovery, which will not only produce environmentally acceptable effluents, but are also pertinent in achieving decreased costs for sanitation systems, hence making them more affordable. The decentralised system is cheaper than the centralised system, mainly due to decreased sewer needs and combining it with resource recovery. This provides an opportunity of decreasing costs further due to the several economic benefits attached to the recovered products. Whereas sanitation involves both wastewater and solid waste, this review paper discusses the current sanitation situation in Africa and proposes a wastewater management plan that could contribute to improvement for small agricultural communities. The plan encourages zero waste generation through decentralisation and recovery of water, energy and by-products such as nutrients and organics relevant to the local community. Apart from the proposed technological strategies, a winning sanitation management plan should also be appreciated and supported by all stakeholders, which can be achieved through proper communication and integration of local user needs.  相似文献   

4.
Water, sanitation and hygiene interventions have been advocated as important complements to deworming programs to improve soil-transmitted helminth control. Evidence for the impact of water, sanitation and hygiene on soil-transmitted helminth infections is mixed, and based mainly on cross-sectional studies. In this study, we assessed associations between individual- and household-level water, sanitation and hygiene variables and soil-transmitted helminth infections, using data collected during the 2?year follow-up study period of the WASH for WORMS randomised controlled trial in Timor-Leste. Data were collected across four surveys, conducted at 6 monthly intervals in 23 communities. We analysed water, sanitation and hygiene and sociodemographic variables as risk factors for infection with Necator americanus, Ascaris spp., and undifferentiated soil-transmitted helminth infection, using generalised linear mixed models to account for clustering at community, household and participant levels. Water, sanitation and hygiene risk factors were examined both concurrently and with a 6?month lag period that coincided with the most recent deworming. The analysis included 2333 participants. Factors associated with N. americanus infection included age group, male sex (adjusted odds ratio (aOR) 3.1, 95% confidence interval (CI) 2.4–4.2), working as a farmer (aOR 1.7, 95% CI 1.2–2.4), and completing secondary school or higher (aOR 0.29, 95% CI 0.16–0.53). Risk factors for Ascaris spp. infection included age group, living in a dwelling with more than six people (aOR 1.6, 95% CI 1.1–2.3), having a tube well or borehole as the household water source (aOR 3.7, 95% CI 1.3–10.8), and using a latrine shared between households 6?months previously (aOR 2.3, 95% CI 1.2–4.3). Handwashing before eating was protective against infection with any soil-transmitted helminth (aOR 0.79, 95% CI 0.65–0.95). In the context of regular deworming, few water, sanitation and hygiene-related factors were associated with soil-transmitted helminth infections. Future research examining the role of water, sanitation and hygiene in soil-transmitted helminth transmission is required, particularly in low transmission settings after cessation of deworming. Identifying improved indicators for measuring water, sanitation and hygiene behaviours is also a key priority.  相似文献   

5.
Child mortality differentials according to water supply and sanitation in many urban areas of developing countries suggest that access to piped water and toilet facilities can improve the survival chances of children. The central question in this study is whether access to piped water and a flush toilet affects the survival chance of children under five in urban areas of Eritrea. The study uses data collected by the Demographic and Health Survey (DHS) project in Eritrea in 1995. The results show that while the unadjusted effect of household environment (water supply and toilet facility) is large and statistically significant during the post-neonatal and child periods, it is relatively small and statistically insignificant during the neonatal period. The effect of household environment remains substantial during the post-neonatal and child periods, even when other socioeconomic variables are held constant. However, the household environment effect totally disappears during the neonatal period when the socioeconomic factors are controlled for.  相似文献   

6.
Africa, though reported to be the least urbanized continent, is recognized as one where the rate of urbanization is highest. The development and expansion of informal settlements in the suburbs of the cities is widespread, while they harbor the majority of the urban population. Slums are characterized by, among other things, poorly constructed houses, poor water supply and sanitary conditions, and lack or inadequate support services. Besides the spreading of diseases related to surface water (e.g., malaria), one of the main problems associated with sanitation and water in slum areas is related to the pollutant load entering and leaving the slum catchment, either as surface water or groundwater. This is polluting drinking water or causing eutrophication of surface water, due to the extremely high nitrogen and phosphorus fluxes discharging those slum catchments. The SCUSA research project aims at identifying the most sustainable sanitation solutions in urban slums, including the most important parameters determining and guaranteeing sustainability. Our approach is multidisciplinary, and should therefore yield answers with a financial, social, technical, and environmental view on the extremely complex field of sanitation in urban slums.  相似文献   

7.
BackgroundTrachoma is a worldwide infectious disease causing blindness. Trachoma continued as a public health problem in Ethiopia due to a lack of sanitation and inadequate prevention strategies. This study aimed to identify the impact of water supply and sanitation intervention on preventing active trachoma among children.MethodsSystematic literature searches were performed from 4 international databases. The search involved articles published from January 1995 up to March 2019. The Cochran Q and I2 statistical tests were used to check heterogeneity among the studies. A random-effect meta-analysis was employed to determine the pooled estimates with a 95% confidence interval (CI). Data analysis was performed using the CMA V.3 and RevMan 5 software program, and the result of the systematic review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.FindingsOut of 211 studies screened for the analysis, only 29 studies were finally included in this systematic review and meta-analysis. The result revealed factors that are significantly associated with increased odds of active trachoma. Accordingly, households with no access to toilet facilities (odds ratio [OR]: 2.04, 95% CI: 1.75–2.38), no access to improved water (OR: 1.58, 95% CI: 1.27–1.96), and do not practice regular face washing for children (OR: 4.19, 95% CI: 3.02–5.81) have shown increased odds of active trachoma. Besides, the results show a higher prevalence of active trachoma among children who did not wash their faces with soap and frequently.ConclusionsThe study found strong evidence that lack of access to water, sanitation, and hygiene (WASH) was associated with increased prevalence of active trachoma among children. Therefore, a comprehensive and partnership-oriented program is needed to tackle the problem, but further study will be required to strengthen its implementation.  相似文献   

8.
Poor sanitation in urban slums results in increased prevalence of diseases and pollution of the environment. Excreta, grey water and solid wastes are the major contributors to the pollution load into the slum environment and pose a risk to public health. The high rates of urbanization and population growth, poor accessibility and lack of legal status in urban slums make it difficult to improve their level of sanitation. New approaches may help to achieve the sanitation target of the Millennium Development Goal (MDG) 7; ensuring environmental sustainability. This paper reviews the characteristics of waste streams and the potential treatment processes and technologies that can be adopted and applied in urban slums in a sustainable way. Resource recovery oriented technologies minimise health risks and negative environmental impacts. In particular, there has been increasing recognition of the potential of anaerobic co-digestion for treatment of excreta and organic solid waste for energy recovery as an alternative to composting. Soil and sand filters have also been found suitable for removal of organic matter, pathogens, nutrients and micro-pollutants from grey water.  相似文献   

9.
Egg rejection in birds is a specific adaptation toward avian brood parasitism, whereas nest sanitation is a general behavior for cleaning the nest and avoiding predation. However, both behaviors refer to the action of ejecting objects out of the nest, and nest sanitation has been proposed as a pre-adaptation for egg rejection. Here, we tested the eliciting effect of nest sanitation on egg rejection in the red-whiskered bulbul Pycnonotus jocosus, a potential host species that are sympatric with parasitic cuckoos. We conducted meta-analyses of previous studies on both nest sanitation and egg rejection, in order to evaluate the consistency of our conclusions. Our results showed that nest sanitation did not elicit egg rejection in P. jocosus. The conclusions concerning such an eliciting effect from previous studies were mixed, whereas the methodologies were inconsistent, making the studies unsuitable for comparisons. However, the ejection frequency of nest sanitation was consistently higher than the frequency of egg rejection across different host species or populations. These results suggest that nest sanitation, which is an ancient behavior, is more fundamental than egg rejection, but the effect of the former on the latter is complex and needs further study. Standardized methodologies and the integration of behavior, physiology, and modeling may provide better opportunities to explore the relationship between nest sanitation and egg rejection.  相似文献   

10.
Contaminated water causes an estimated 6 to 60 billion cases of gastrointestinal illness annually. The majority of these cases occur in rural areas of developing nations where the water supply remains polluted and adequate sanitation is unavailable. A portable, low-cost, and low-maintenance solar unit to disinfect unpotable water has been designed and tested. The solar disinfection unit was tested with both river water and partially processed water from two wastewater treatment plants. In less than 30 min in midday sunlight, the unit eradicated more than 4 log10 U (99.99%) of bacteria contained in highly contaminated water samples. The solar disinfection unit has been field tested by Centro Panamericano de Ingenieria Sanitaria y Ciencias del Ambiente in Lima, Peru. At moderate light intensity, the solar disinfection unit was capable of reducing the bacterial load in a controlled contaminated water sample by 4 log10 U and disinfected approximately 1 liter of water in 30 min.  相似文献   

11.
Appropriate technologies for environmental hygiene usually centre on the delivery of adequate and accessible water supply, and proper treatment and disposal of excreta and refuse. In the face of the International Drinking Water and Sanitation Decade of 1981-90, several research efforts are under way in the developing countries to develop technologies and approaches for improving environmental hygiene in both rural areas and urban squatter settlements. These are discussed and include the technical development and field testing of infiltration galleries, low-cost slow and fast filtration processes for water treatment, handpumps, on-site excreta disposal using aqua-privy and compost toilets, and excreta treatment and refuse through composting with refuse, biogas generation, fish culture and use of excreta as crop fertilizer. The relevant technology 'hardware' is but one of several components necessary for effective delivery of services. The dearth of qualified manpower at all levels is described as being the major constraint to the Water and Sanitation Decade.  相似文献   

12.
ABSTRACT: BACKGROUND: Greaves "delayed infection" hypothesis suggested that Acute Lymphoblastic Leukemia (ALL) in children is caused by a lack of exposure to infection in infancy, which may be due higher standards of sanitation. We have conducted an ecologic analysis of the relationship between sanitation, using Helicobacter pylori (H. pylori) as the marker, and the incidence of childhood ALL in 127 cancer registries from 28 countries. RESULTS: There were inverse associations between H. pylori perverse and ALL incidence rates in children. These associations were minor and only significant for ALL incidence rates for all cancer registries. They became non-significant and smaller in magnitude when the population source and/or the GNP per capita were added to the relationship. Furthermore, these results were unchanged when the associations were examined using the Generalized Estimating Equations. CONCLUSIONS: Although the findings showed lower prevalence of H. pylori and improved sanitation is associated with increased incidence of childhood ALL, they do not conclusively support Greaves "delayed infection" hypothesis.  相似文献   

13.
Applied Microbiology and Biotechnology - In the fresh produce industry, validation of sanitation efficacy is critical to prevent cross-contamination of produce. The current validation approaches...  相似文献   

14.
The problem of inadequate access to water, sanitation and hygiene (WASH) in less-developed nations has received much attention over the last several decades (most recently in the Millennium Development Goals), largely because diseases associated with such conditions contribute substantially to mortality in poor countries. We present country-level projections for WASH coverage and for WASH-related mortality in developing regions over a long time horizon (1975–2050) and provide dynamic estimates of the economic value of potential reductions in this WASH-related mortality, which go beyond the static results found in previous work. Over the historical period leading up to the present, our analysis shows steady and substantial improvements in WASH coverage and declining mortality rates across many developing regions, namely East Asia and the Pacific, Latin America and the Caribbean, Eastern Europe and the Middle East. The economic value of potential health gains from eliminating mortality attributable to poor water and sanitation has decreased substantially, and in the future will therefore be modest in these regions. Where WASH-related deaths remain high (in parts of South Asia and much of Sub-Saharan Africa), if current trends continue, it will be several decades before economic development and investments in improved water and sanitation will result in the capture of these economic benefits. The fact that health losses will likely remain high in these two regions over the medium term suggests that accelerated efforts are needed to improve access to water and sanitation, though the costs and benefits of such efforts in specific locations should be carefully assessed.  相似文献   

15.
The plant nutrients consumed in human society today are lost through the established wastewater treatment systems in industrialised countries as well as via insufficient or non-existent handling of sewage in the developing world. New sanitation systems have been designated to overcome this failure. The source separated wastewater streams collected within these systems contain a high nutrient content, and can be used as fertiliser as well as soil conditioner after appropriate storage and/or treatment. Application in agriculture with existing techniques is feasible. However, pathogens and pharmaceuticals contained in these fertiliser types are a potential hazard. Nevertheless, storage and appropriate treatment can minimise the risks. The products deriving from these systems have a high potential to preserve available plant nutrient resources and deficiencies in agriculture as well as being able to substitute synthetic plant nutrients and at the same time prevent unwanted environmental nutrient over-enrichment.  相似文献   

16.
Regression analyses were conducted between water pollutants discharges per capita (PDC) and gross domestic production per capita (GDPC) of developing countries in seven international coastal and lakeside Regions. Regional groupings of PDCs and GDPC were identified with graphical analyses. The inverted-U shaped curve relationships, namely environmental Kuznets curve (EKC), were found for biological oxygen demand (BOD) discharge per capita (PDC-BOD) and total phosphorus (TP) discharge per capita (PDC-TP) with a peak at ca. US$5, 050 and US$11,200, respectively, besides lower significance for PDC-BOD. Total nitrogen (TN) discharge per capita (PDC-TN) decreased linearly with GDPC increase. Possible reasons for the different tendencies of PDC-BOD, PDC-TN and PDC-TP with GCP per capita are that nutrient removal is introduced after economic development to some extent, and main nitrogen source is blackwater especially urine in domestic wastewater. Pollutants discharges reduction should be targeted with the relevant indicators to improve the ambient water quality especially after the achievement of the sanitation millennium development goals (MDGs) because the sanitation MDGs indicator mainly targets infectious diseases, hygiene health and lifestyle improvement, and there are several kinds of domestic wastewater treatment methods in the world.  相似文献   

17.
Emerging evidence demonstrates how inadequate access to water and sanitation is linked to psychosocial stress, especially among women, forcing them to navigate social and physical barriers during their daily sanitation routines. We examine sanitation-related psychosocial stress (SRPS) across women’s reproductive lives in three distinct geographic sites (urban slums, rural villages, and rural tribal villages) in Odisha, India. We explored daily sanitation practices of adolescent, newly married, pregnant, and established adult women (n = 60) and identified stressors encountered during sanitation. Responding to structured data collection methods, women ranked seven sanitation activities (defecation, urination, menstruation, bathing, post-defecation cleaning, carrying water, and changing clothes) based on stress (high to low) and level of freedom (associated with greatest freedom to having the most restrictions). Women then identified common stressors they encountered when practicing sanitation and sorted stressors in constrained piles based on frequency and severity of each issue. The constellation of factors influencing SRPS varies by life stage and location. Overall, sanitation behaviors that were most restricted (i.e., menstruation) were the most stressful. Women in different sites encountered different stressors, and the level of perceived severity varied based on site and life stage. Understanding the influence of place and life stage on SRPS provides a nuanced understanding of sanitation, and may help identify areas for intervention.  相似文献   

18.
Birds’ behavioral response to brood parasitism can be influenced not only by evolution but also by context and individual experience. This could include nest sanitation, in which birds remove debris from their nests. Ultimately, nest sanitation behavior might be an evolutionary precursor to the rejection of parasitic eggs. Proximately, the context or experience of performing nest sanitation behavior might increase the detection or prime the removal of parasitic eggs, but evidence to date is limited. We tested incubation-stage nests of herring gulls Larus argentatus to ask whether nest sanitation increased parasitic egg rejection. In an initial set of 160 single-object experiments, small, red, blocky objects were usually rejected (18 of 20 nests), whereas life-sized, 3D-printed herring gull eggs were not rejected whether red (0 of 20) or the olive-tan base color of herring gull eggs (0 of 20). Next, we simultaneously presented a red, 3D-printed gull egg and a small, red block. These nests exhibited frequent nest sanitation (small, red block removed at 40 of 48 nests), but egg rejection remained uncommon (5 of those 40) and not significantly different from control nests (5 of 49) which received the parasitic egg but not the priming object. Thus, performance of nest sanitation did not shape individuals’ responses to parasitism. Interestingly, parents were more likely to reject the parasitic egg when they were present as we approached the nest to add the experimental objects. Depending on the underlying mechanism, this could also be a case of experience creating variation in responses to parasitism.  相似文献   

19.
Safe drinking water and sanitation are important determinants of human health and wellbeing and have recently been declared human rights by the international community. Increased access to both were included in the Millennium Development Goals under a single dedicated target for 2015. This target was reached in 2010 for water but sanitation will fall short; however, there is an important difference in the benchmarks used for assessing global access. For drinking water the benchmark is community-level access whilst for sanitation it is household-level access, so a pit latrine shared between households does not count toward the Millennium Development Goal (MDG) target. We estimated global progress for water and sanitation under two scenarios: with equivalent household- and community-level benchmarks. Our results demonstrate that the “sanitation deficit” is apparent only when household-level sanitation access is contrasted with community-level water access. When equivalent benchmarks are used for water and sanitation, the global deficit is as great for water as it is for sanitation, and sanitation progress in the MDG-period (1990–2015) outstrips that in water. As both drinking water and sanitation access yield greater benefits at the household-level than at the community-level, we conclude that any post–2015 goals should consider a household-level benchmark for both.  相似文献   

20.
Abstract

This study evaluated the drinking water quality and associated human health risks in three (3) rural and urban areas each in Ibeju-Lekki and Epe local government areas of Lagos, Nigeria. Two hundred structured questionnaires were administered to stakeholders, and samples were obtained from prevailing drinking water sources in the study areas using standard methods for microbiological, physicochemical, heavy metals and human health risk evaluations. Wells and boreholes were the major sources of drinking water in the rural and urban areas, respectively. Drinking water samples from the study areas contained more than one pathogenic bacterium. The physicochemical parameters except total organic carbon (TOC) were within permissible limits of the Nigerian Standard for Drinking Water Quality (NSDWQ). The mean values of Cd and As exceeded the maximum permissible limit of NSDWQ. The hazard quotient of cadmium and arsenic was greater than 1 indicating potential health risks if the water is not treated. In order to achieve the UN Sustainable Development Goal 6 on clean water and sanitation by the next decade (2030), we recommend that frequent monitoring, treatment and stakeholders education on drinking water treatment techniques should be actively conducted particularly in rural areas in the state, country, region and continent.  相似文献   

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