Department Of Public Health Engineering Research Articles

Institutional capacity assessment in the lens of implementation research: Capacity of the local institutions in delivering WASH services at Cox's Bazar district, Bangladesh.

The influx of Forcibly Displaced Myanmar Nationals (FDMNs) has left the Southwest coastal district of Cox's Bazar with one of the greatest contemporary humanitarian crises, stressing the existing water, sanitation, and hygiene (WASH) resources and services. This study aimed to assess the existing capacity of local institutions involved in delivering WASH services and identify relevant recommendations for intervention strategies. We used a qualitative approach, including interviews and capacity assessment workshops with institutions engaged in WASH service delivery. We conducted five key informant interviews (KII) with sub-district level officials of the Department of Public Health Engineering (DPHE), Directorate General of Health Services (DGHS), Directorate of Primary Education (DPE) and Bangladesh Rural Advancement Committee (BRAC) to have a general idea of WASH service mechanisms. Seven capacity assessment workshops were organized with the relevant district and sub-district level stakeholders from August 2019 to September 2019. These workshops followed three key areas: i) knowledge of policy, organizational strategy, guidelines, and framework; ii) institutional arrangements for service delivery such as planning, implementation, coordination, monitoring, and reporting; and iii) availability and management of human, financial and infrastructural resources. Data were categorized using thematic content analysis. The majority of stakeholders lacked awareness of national WASH policies. Furthermore, the top-down planning approaches resulted in activities that were not context-specific, and lack of coordination between multiple institutions compromised the optimal WASH service delivery at the local level. Shortage of human resources in delivering sustainable WASH services, inadequate supervision, and inadequate evaluation of activities also required further improvement, as identified by WASH stakeholders. Research evidence suggests that decision-makers, donors, and development partners should consider learning from the WASH implementers and stakeholders about their existing capacity, gaps, and opportunities before planning for any WASH intervention in any particular area.

Factors affecting the performance of household rainwater harvesting systems in the south-western coastal region of Bangladesh

Abstract This study aims to evaluate the post-installation performance of household (HH) rainwater harvesting (RWH) systems in the southwestern coastal region of Bangladesh. A conceptual framework for evaluating the effectiveness of RWH systems was developed based on seven determinants. An application of multivariable logistic regression showed that family size, monthly income, the practice of tank and downpipe cleaning, and the organizations supporting the installation were the most significant parameters (p< 0.05) affecting the effectiveness of the RWH systems. A family size of 1–4 has higher odds of having a properly functioning system (adjusted odds ratio (AOR) = 28.3; 95% confidence interval (CI) = 4.8–167.7) than a family of 9 or more. The practice of tank cleaning once per year (AOR = 3.3; 95% CI = 1.2–9.1) and downpipe cleaning more than 3 times/year (AOR = 9.7; 95% CI = 1.5–62.5) had higher odds than HHs practicing no cleaning at all. RWH systems installed by institutions other than the Department of Public Health Engineering, and NGOs had higher odds (AOR = 22.0; 95% CI = 2.3–213.0) compared to systems installed on their own. This study provides clues to strengthening the existing RWHS intervention programs in the water-challenged regions of Bangladesh.

Deadly Wells in Bangladesh

This case allows instructors to lay out the challenges of providing universal access to safe drinking water in some developing and emerging countries—one of the current UN development goals. The challenge across developing countries is to find long-lasting and sustainable solutions, and to realize that present answers to the challenge may be a far cry from these criteria. The discussion aims to address the complex and multifaceted nature of water supply in developing countries, and to emphasize that many of the assumptions made in advanced economies may not apply. The aim is to search for the best (long-lasting and sustainable) solutions, admitting there is no silver bullet, even though some alternatives are clearly better than others. Excerpt UVA-GEM-0158 Oct. 1, 2019 Deadly Wells in Bangladesh In the early 1980s, K.C. Saha from the Calcutta School of Tropical Medicine in India successfully related skin lesions in the Indian state of West Bengal to arsenic in groundwater. In 1992, researchers under the direction of Dipankar Chakraborti from the School of Environmental Studies at Jadavpur University came across an unusual female patient while they were active in the arsenic-affected village of Gobindapur in West Bengal. She was the only one in her West Bengali family with lesions, but she had migrated from Bangladesh after her marriage. It turned out that many of her Bangladeshi relatives had similar lesions, and she had noticed lesions in residents of neighboring Bangladesh villages as well. Soon suspicions were confirmed of arsenic contamination in Bangladesh. In 1994, the World Health Organization (WHO) and the United Nations International Children's Emergency Fund (UNICEF) were notified but slow to take action, as were Bangladeshi institutions. Reportedly in 1993, Bangladesh's Department of Public Health Engineering (DPHE) had already confirmed arsenic contamination in tube wells, which were PVC pipes with a cast-iron hand pump on top. The country and the international health community awoke to the reality and magnitude of the challenge in 1998, when an international conference was convened in Bangladesh's capital, Dhaka. In 2000, the Bulletin of the World Health Organization described Bangladesh's predicament in the strongest possible terms, which would resonate for many years to come: Bangladesh is grappling with the largest mass poisoning of a population in history because groundwater used for drinking has been contaminated with naturally occurring inorganic arsenic. It is estimated that of the 125million inhabitants of Bangladesh, between 35million and 77million are at risk of drinking contaminated water. The scale of this environmental disaster is greater than any seen before; it is beyond the accidents at Bhopal, India, in 1984, and Chernobyl, Ukraine, in 1986. . . .

Arsenic and fasting blood glucose in the context of other drinking water chemicals: a cross-sectional study in Bangladesh

GoalThe goal of this study was to evaluate the association between groundwater arsenic and fasting blood glucose in the context of other groundwater chemicals, in Bangladesh. MethodsFasting blood glucose, gender, body mass index, sociodemographic variables, and diabetes medication use were measured among adults ≥ 35 years of age (n = 6587) participating in the Bangladesh Demographic and Health Survey (BDHS) 2011. Groundwater chemicals in 3534 well water samples were measured in the British Geological Survey (BGS) and Department of Public Health Engineering (DPHE) 1998–99 survey. We assigned the nearest BGS-DPHE well's chemical exposure to each BDHS participant. We used survey-estimation linear regression methods to model natural log-transformed fasting blood glucose, among those using groundwater as their primary drinking-water source, as a function of groundwater arsenic. We considered possible interactions between categorical arsenic exposure and each of 14 other groundwater chemicals dichotomized at their medians. The chemicals considered as possible effect modifiers included: aluminum, barium, calcium, iron, potassium, lithium, magnesium, manganese, sodium, phosphorous, silicon, sulfate, strontium, and zinc. ResultsCompared to persons exposed to groundwater arsenic ≤ 10 μg/L, the adjusted geometric mean ratio (GMR) of fasting blood glucose was 1.01 (95% confidence interval: 0.98, 1.04) for individuals exposed to groundwater arsenic concentrations > 10 μg/L and ≤ 50 μg/L, and was 1.01 (0.97, 1.03) for those with > 50 μg/L arsenic. There were no Bonferroni-significant interactions with other chemicals, after accounting for the large number of chemicals tested as modifiers. ConclusionsIn our analysis of groundwater chemistry data from 1998/99 and fasting blood glucose outcomes measured in nearby populations approximately a decade later, there was no overall association of fasting blood glucose with nearby historical groundwater arsenic. This null association was not significantly modified by the historical levels of other groundwater chemicals. These null results are inconclusive regarding shorter-term potential toxicity of arsenic for glucose regulation, if there are differences between the historical concentrations measured in nearby groundwater and the actual drinking water chemical exposures in the population during the etiologically relevant period for more acute phenotypes like fasting blood glucose. Drinking water supply-relevant, longitudinal exposure assessment with less measurement error is needed to more precisely evaluate the joint impacts of drinking water chemicals and establish if there is a sensitive time window for glycemic outcomes.

Groundwater Arsenic and Fasting Blood Glucose in the Context of Other Groundwater Chemicals: A Cross-Sectional Study in Bangladesh

Goal: To evaluate the association between groundwater arsenic (As) and fasting blood glucose (FBG), in the context of other groundwater chemicals, in Bangladesh. Methods: FBG and demographics were measured among adults ≥ 35 years of age (n=6,587) participating in the Bangladesh Demographic and Health Survey (BDHS) 2011. Groundwater chemicals in 3,534 well water samples were measured in the British Geological Survey (BGS) and Department of Public Health Engineering (DPHE) 1998-99 survey. In this analysis, we assigned the nearest BGS-DPHE well’s chemical exposure to each BDHS participant. Survey-estimation linear regression methods were used to model log-transformed FBG, among those using groundwater as primary drinking-water source, as a function of groundwater As, adjusting for age, sex, BMI, smoking status, diabetes medication use, region, rural or urban residence, household wealth, and educational attainment. We considered interactions of As with 14 other groundwater chemicals. Results: Compared to persons exposed to groundwater As < 10 mg/L, the geometric mean ratio (GMR) of FBG was 1.01 (95% confidence interval: 0.98, 1.04) for individuals exposed to groundwater As concentrations ≥10 mg/L and<50 mg/L, and was 1.01 (0.97, 1.03) for those with ≥50 mg/L water As. Low K water may have potentiated As toxicity: among persons with low water K, the GMR of FBG for the ≥10 and < 50 As range vs. < 10 mg/L was 1.03 (1.00, 1.07), and for ≥ 50 vs.< 10 mg/Lwas 1.06 (1.01, 1.11). Persons with low Ca and persons with low Mg also had higher GMR of FBG in the ≥10 and < 50 mg/L As group vs. <10 mg/L As. However, after Bonferroni correction no associations were significant. Conclusions: We did not detect an overall association between As and FBG. This may be due to exposure misclassification. It is possible that low groundwater K, Ca, or Mg exacerbated As toxicity to detectible levels despite exposure misclassification, but these could be false positives from multiple testing.

Groundwater arsenic contamination in Bangladesh—21 Years of research

Department of Public Health Engineering (DPHE), Bangladesh first identified their groundwater arsenic contamination in 1993. But before the international arsenic conference in Dhaka in February 1998, the problem was not widely accepted. Even in the international arsenic conference in West-Bengal, India in February, 1995, representatives of international agencies in Bangladesh and Bangladesh government attended the conference but they denied the groundwater arsenic contamination in Bangladesh. School of Environmental Studies (SOES), Jadavpur University, Kolkata, India first identified arsenic patient in Bangladesh in 1992 and informed WHO, UNICEF of Bangladesh and Govt. of Bangladesh from April 1994 to August 1995. British Geological Survey (BGS) dug hand tube-wells in Bangladesh in 1980s and early 1990s but they did not test the water for arsenic. Again BGS came back to Bangladesh in 1992 to assess the quality of the water of the tube-wells they installed but they still did not test for arsenic when groundwater arsenic contamination and its health effects in West Bengal in Bengal delta was already published in WHO Bulletin in 1988. From December 1996, SOES in collaboration with Dhaka Community Hospital (DCH), Bangladesh started analyzing hand tube-wells for arsenic from all 64 districts in four geomorphologic regions of Bangladesh. So far over 54,000 tube-well water samples had been analyzed by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). From SOES water analysis data at present we could assess status of arsenic groundwater contamination in four geo-morphological regions of Bangladesh and location of possible arsenic safe groundwater. SOES and DCH also made some preliminary work with their medical team to identify patients suffering from arsenic related diseases. SOES further analyzed few thousands biological samples (hair, nail, urine and skin scales) and foodstuffs for arsenic to know arsenic body burden and people sub-clinically affected. SOES and DCH made a few follow-up studies in some districts to know their overall situations after 9 to 18 years of their first exposure. The overall conclusion from these follow-up studies is (a) villagers are now more aware about the danger of drinking arsenic contaminated water (b) villagers are currently drinking less arsenic contaminated water (c) many villagers in affected village died of cancer (d) arsenic contaminated water is in use for agricultural irrigation and arsenic exposure from food chain could be future danger. Since at present more information is coming about health effects from low arsenic exposure, Bangladesh Government should immediately focus on their huge surface water management and reduce their permissible limit of arsenic in drinking water.

Predicting arsenic concentration in groundwater of Bangladesh using Bayesian geostatistical model

The pattern of the spatial variation in arsenic concentration in groundwater of Bangladesh is usually needed for the planning of safe drinking water. Often a model-based prediction is required for this purpose. In this paper, we fit a Bayesian hierarchical geostatistical model by utilizing data from the project, ‘Groundwater studies of arsenic concentration in Bangladesh’ conducted by the British Geological Survey and the Department of Public Health Engineering of Bangladesh. We also develop a predictive model for arsenic concentration at different levels of well-depth using the same approach. The resulting predictive model has been cross-validated by appropriate statistical tools. Finally, we obtained reliable spatially continuous predictive maps and predictive probability maps showing the areas with high probability of arsenic concentration for different levels of well-depth. Results indicate that our model fits the data well and captures a substantial amount of spatial variation. Moreover, well-depth is found to have a significant contribution in explaining the observed variation in arsenic concentration. The predictive maps that have been produced are observed to be different for various levels of well-depths and are expected to be helpful to the policy makers in preparing proper regional planning for safe drinking water.

Zonal management of arsenic contaminated ground water in Northwestern Bangladesh

This paper used ordinary kriging to spatially map arsenic contamination in shallow aquifers of Northwestern Bangladesh (total area ∼ 35,000 km 2). The Northwestern region was selected because it represents a relatively safer source of large-scale and affordable water supply for the rest of Bangladesh currently faced with extensive arsenic contamination in drinking water (such as the Southern regions). Hence, the work appropriately explored sustainability issues by building upon a previously published study ( Hossain et al., 2007; Water Resources Management, vol. 21: 1245–1261) where a more general nation-wide assessment afforded by kriging was identified. The arsenic database for reference comprised the nation-wide survey (of 3534 drinking wells) completed in 1999 by the British Geological Survey (BGS) in collaboration with the Department of Public Health Engineering (DPHE) of Bangladesh. Randomly sampled networks of zones from this reference database were used to develop an empirical variogram and develop maps of zonal arsenic concentration for the Northwestern region. The remaining non-sampled zones from the reference database were used to assess the accuracy of the kriged maps. Two additional criteria were explored: (1) the ability of geostatistical interpolators such as kriging to extrapolate information on spatial structure of arsenic contamination beyond small-scale exploratory domains; (2) the impact of a priori knowledge of anisotropic variability on the effectiveness of geostatistically based management. On the average, the kriging method was found to have a 90% probability of successful prediction of safe zones according to the WHO safe limit of 10 ppb while for the Bangladesh safe limit of 50 ppb, the safe zone prediction probability was 97%. Compared to the previous study by Hossain et al. (2007) over the rest of the contaminated country side, the probability of successful detection of safe zones in the Northwest is observed to be about 25% higher. An a priori knowledge of anisotropy was found to have inconclusive impact on the effectiveness of kriging. It was, however, hypothesized that a preferential sampling strategy that honored anisotropy could be necessary to reach a more definitive conclusion in regards to this issue.

A Forensic Look at Groundwater Arsenic Contamination in Bangladesh

A comprehensive forensic analysis of AS contamination in Bangladesh was undertaken using geographic information system (GIS), univariate, and bivariate statistics. The assessment provided the background needed for fine-tuning emerging/evolving methods of spatial mapping based on nonlinear deterministic dynamics and multivariate factorial analyses. Data were derived from a nationwide AS survey completed in 1999 by the British Geological Survey (BGS) in collaboration with the Department of Public Health Engineering (DPHE) of Bangladesh. It was found that the standard deviation of arsenic concentration is highest along the river flood plains of the major rivers. The distribution of arsenic concentration was found to be symmetric in regions of very high mean concentration, while the regions of low and moderate contamination reveal a highly skewed distribution, suggesting the need for data transformation at these points prior to spatial interpolation. The mean value of Ca and Mg concentrations showed a strong spatial similarity in the southwest region of Bangladesh. This spatial similarity was also reflected in terms of skewness of the data. It was inferred that the mapping of AS concentrations at nonsampled locations on the basis of multivariate factorial or regression models may not require the dual presence of both Ca and Mg parameters; hence, one of them is redundant. Both the skewness and kurtosis of the distribution of Si concentration appeared very similar and highly heterogeneous in space, suggesting that Si data require careful transformation prior to modeling only in the smaller scale but not for country-wide/regional purposes. The age of wells was found to be nonlinearly correlated in the southeast region. The correlation of AS with Fe appeared strongest in the southwest region, indicating that the oxidation–reduction hypothesis may be more appropriate as a release mechanism in the southwest region. In another regard, the sulphate concentration was found to be more correlated to AS in the northwest Pleistocene region of Bangladesh, suggesting that the pyrite oxidation hypothesis may be appropriate. Overall, our forensic analysis using GIS revealed useful findings for data transformation and selection of parameters towards spatial mapping based on multivariate factorial and nonlinear deterministic models in the resource-poor settings of developing countries.

Arsenic Contamination in Ground Water in Bangladesh

Bangladesh is well known for her natural disasters such as floods and cyclones. Although Bangladesh has a higher amount of water per capita than most countries in the world, she often suffers from water shortages and droughts. Since the 1980s, groundwater (of hand tube wells) has been used for drinking and cooking all over the country to avoid water borne diseases. However, since 1993 tube wells in most parts of Bangladesh have become contaminated with high amounts of arsenic (0.05 mg/liter). In this paper the water situation of a village (Taranagar) severely affected by the arsenic problem is discussed based on a survey conducted in 2005. High levels of arsenic contaminated more than 97% of tube wells in this village. More than 90% of all households had patients with arsenicosis, five patients had already died. However, the villagers still remained almost without any effective alternative for a safe water source. The efforts of the Department of Public Health Engineering (DPHE) to install ring wells proved to be futile, as it was not possible to dig the wells according to the guidelines, and the water of these ring wells had bad odors. The paper concludes by urging all concerned to provide safe water to the people of Taranagar village.

Geostatistically based management of arsenic contaminated ground water in shallow wells of Bangladesh

This paper investigates the effectiveness of geostatistical approaches, specifically ordinary kriging, for regional management of arsenic contaminated shallow ground water in Bangladesh. The arsenic database for reference comprised the nation-wide survey (of 3534 drinking wells) completed in 1999 by the British Geological Survey (BGS) in collaboration with the Department of Public Health Engineering (DPHE) of Bangladesh. A Monte Carlo (MC) framework was devised for selection of randomly-sampled networks of wells from this reference database. Each randomly sampled network was assumed an equi-probable exploratory field campaign designed commensurably with the requirements of rapidity and cost-effectiveness in a rural setting. In general, the kriging method was found to underestimate the arsenic concentration at non-sampled locations. This underestimation exceeded the safe limits at the Holocene region of Southcentral Bangladesh. The probability of successful prediction of safe wells for this region was found to be 72% (WHO safe limit – 10 ppb) and 78% (Bangladesh safe limit – 50 ppb). For the Pleistocene Northwestern region of Bangladesh, the safe well prediction probability was in the ranges of 90%–97%. The relatively more contaminated Holocene region in Southcentral Bangladesh, on other hand, was found more amenable to accurate geostatistical prediction of unsafe wells. Findings from this study exemplify that, while mainstream geostatistical approaches (e.g., ordinary kriging) may not provide the most accurate prediction of mean arsenic concentration at non-sampled locations, they can delineate an approximate strategy for management of arsenic contaminated shallow ground water if applied carefully. The kriging methodology is applied to a test case in Bangladesh; the approach, however, is general and is expected to have application in rural settings for other developing countries where arsenic contamination of ground water is also widespread (e.g., parts of India, Vietnam, Taiwan and Mexico).

Statistical characterization of arsenic contamination in shallow tube wells of western Bangladesh

AbstractA regional assessment of the arsenic (As) contamination scenario in shallow tube wells (depth < 150 m) of western Bangladesh is presented. Comparisons are made in light of bulk geological differences (Pleistocene versus Holocene deposits/northwest versus southwest) and As measurement protocols (field kit (FK) versus atomic absorption spectroscopy (AAS)). Our As database comprised the following: (1) the nationwide As survey completed in 1999 by the British Geological Survey in collaboration with the Department of Public Health Engineering (DPHE); and (2) a regional As survey conducted in southwest Bangladesh by the Japan International Cooperation Agency in collaboration with DPHE in 2002. First, we characterize the error structure of the semi‐quantitative FK As measurements using collocated AAS As measurements as reference from a set of 307 wells located in southwest Bangladesh. The depth distribution of As is identified using a very dense cluster of 2963 wells over a 560 km2 domain. The probability of the FK method for successful detection of a well sample as unsafe (safe) was found to be 96·9% (34·1%) and 95·2% (80·3%) for the World Health Organization (WHO) and Bangladesh safe limits, respectively. Similarly, the probability of false alarms and false hopes for WHO (Bangladesh) safe limits were found to be 3·1% (4·8%) and 87·5% (19·7%), respectively. The depth at which the highest fraction of wells exceeding a given safe limit occurred could still be inferred correctly by FK measurements. A simple bias adjustment procedure on FK As data did not result in a more accurate characterization of depth distribution of As. This indicated that simple error statistics are inadequate for advancing the utility of FKs; rather, an understanding of the complex and multidimensional error structure is required. Regional anisotropy in the spatial dependence of As for the northwest was found to be stronger than the southwest. The correlation length for As concentration in the east–west direction of northwest Bangladesh (i.e. across major river floodplains) was found to be almost twice (158·80 km) that of the north–south direction (along the major axis of Pleistocene deposits) (78·21 km). For the southwest region, the ratio of east–west to north–south correlation lengths ranged from 1·40 to 1·51. For the northwest region, because it is well known to have the lowest concentrations of As countrywide, knowledge of this anisotropy appears to suggest the need for drilling twice as many remediation deep wells in the proximity of an unsafe shallow well in the north–south direction than in the east–west direction. Findings from this study are potentially useful in setting priority areas for emergency testing, distributing remediation resources equitably and formulating a regional water resources strategy for western Bangladesh. Copyright © 2005 John Wiley & Sons, Ltd.

Spatial pattern of arsenic contamination in shallow wells of Bangladesh: regional geology and nonlinear dynamics

Since the discovery of large-scale arsenic contamination of groundwater in Bangladesh more than a decade ago, studies related to its spatial characterization have relied on geostatistical approaches and the classical notion of linear stochastic dynamics. This study explores an alternative nonlinear approach, with a motivation to possibly achieve more cost-effective solutions for Bangladesh. It investigates the existence of nonlinear deterministic and chaotic dynamic behavior in the spatial pattern of arsenic contamination in the shallow wells (depth<150 m). The database comprises the nationwide arsenic survey completed in 1999 by the British Geological Survey (BGS) in collaboration with the Department of Public Health Engineering (DPHE) of Bangladesh. Distinction is made in terms of regional geology (Pleistocene vs. Holocene deposits/Northwest vs. Southwest) to understand the geologic dependency. Identification of possible presence of nonlinear deterministic and chaotic patterns is made via the Grassberger-Procaccia correlation dimension algorithm. The analysis yields correlation dimension values ranging anywhere from 8 to 11 depending on the region, suggesting that the arsenic contamination in space, from a chaotic dynamic perspective, is a medium- to high-dimensional problem. The dimension results also indicate that the spatial dynamics of arsenic may be moderately sensitive to geology, with Pleistocene aquifers appearing to require a minimum of about two less dominant processes/variables for its description when compared to that required by the Holocene aquifers. Based on these results, a qualitative discussion is also cast on the potential opportunities offered by a nonlinear deterministic and chaotic dynamic approach towards improving cost-effectiveness in siting new safe wells.