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Background Commercial fishing is a precarious industry with high fatal and nonfatal injury rates. The Risk Information System of Commercial [RISC] Fishing project at Oregon State University has been tracking both fatal and nonfatal injuries among Pacific Northwest commercial fishermen. We conducted a hazard analysis to identify injury-associated factors to highlight prevention opportunities. Method We identified 245 nonfatal commercial fishing injuries in the Pacific Northwest (2000-2018) and assessed the top three injury events (contact with objects or equipment, transportation incidents, and slips-trips-falls). We generated a Haddon matrix for each event type and populated the matrices with injury-associated factors following our a-priori matrix. Results We observed 108 nonfatal injuries due to contact with objects. Fishing gear (40%) was the dominant injury source. The top work process was hauling the fishing gear (22%). Handling heavy loads (32%) and contact with unsecured objects (27%) often resulted in contact injuries. Of the 58 transportation injuries most occurred in the catcher-vessels (93%) and smaller vessels (< 5 crew) (74%). Vessel casualties (91%) were common as several vessels struck rocks/bottom (29%) or experienced fire and explosion (19%). The crew was abandoned to water (38%) due to no raft or raft malfunctions. Slip, trip, and fall injuries (n = 43) typically happened during onboard traffic (49%). Such events were largely experienced by the catcher-processors (44%) including large vessels with >100 crew (28%). Conclusion The Haddon matrix demonstrated the injury-event timeline and helped to identify potential injury-associated factors. Our injury-specific risk matrices will let commercial fishing stakeholders determine priorities and work with the experts on prevention efforts.

Advisory boards play a key role in guiding and informing research programs, including occupational health surveillance. It is important to evaluate the effectiveness of these advisory boards. This report details the organization of the Risk Information System for Commercial (RISC) Fishing Technical Advisory Board (TAB), the approach taken to evaluate the TAB, and the results of the evaluation. The RISC TAB was formed to provide advice and recommendations to the study team and informed the development and use of the safety surveillance system.The evaluation approach was informed by limited previous literature on advisory board assessments. This evaluation was conducted in Year 5 of the 6-year project. A review of the meeting notes, materials and correspondences, and study progress was conducted internally to document input from the board and associated actions. To obtain member perspectives, we surveyed the TAB and discussed it in a subsequent TAB meeting.The RISC Fishing TAB members constitute a wide variety of commercial fishing safety stakeholders. The internal analysis identified the main project aspects and 14 of the proposed changes from the TAB that have either been implemented or are in progress in the project. Ten of the 15 TAB members responded indicating a positive experience on board organization and conduct.Evaluation of advisory boards is an essential part of a research program. A process is outlined in this report to inform future efforts to document measurable ways to inform projects based on advisory board feedback and reflections.

Pit latrines are the most common latrine technology in rural Bangladesh, and untreated effluent from pits can directly contaminate surrounding aquifers. Sand barriers installed around the latrine pit can help reduce contamination but can also alter the decomposition of the fecal sludge and accelerate pit fill-up, which can counteract their benefits. We aimed to evaluate whether there was a difference in decomposition of fecal sludge and survival of soil-transmitted helminth (STH) ova among latrines where a 50-cm sand barrier was installed surrounding and at the bottom of the pit, compared to latrines without a sand barrier, in coastal Bangladesh. We assessed decomposition in latrine pits by measuring the carbon-nitrogen (C/N) ratio of fecal sludge. We enumerated Ascaris lumbricoides and Trichuris trichiura ova in the pit following 18 and 24 months of latrine use. We compared these outcomes between latrines with and without sand barriers using generalized linear models with robust standard errors to adjust for clustering at the village level. The C/N ratio in latrines with and without a sand barrier was 13.47 vs. 22.64 (mean difference: 9.16, 95% CI: 0.15, 18.18). Pits with sand barriers filled more quickly and were reportedly emptied three times more frequently than pits without; 27/34 latrines with sand barriers vs. 9/34 latrines without barriers were emptied in the previous six months. Most reported disposal methods were unsafe. Compared to latrines without sand barriers, latrines with sand barriers had significantly higher log10 mean counts of non-larvated A. lumbricoides ova (log10 mean difference: 0.35, 95% CI: 0.12, 0.58) and T. trichiura ova (log10 mean difference: 0.47, 95% CI: 0.20, 0.73). Larvated ova counts were similar for the two types of latrines for both A. lumbricoides and T. trichiura. Our findings suggest that sand barriers help contain helminth ova within the pits but pits with barriers fill up more quickly, leading to more frequent emptying of insufficiently decomposed fecal sludge. Further research is required on latrine technologies that can both isolate pathogens from the environment and achieve rapid decomposition.

Goal The 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. Methods Fasting 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. Results Compared 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. Conclusions In 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.

OBJECTIVES: Commercial fishing is a high-risk occupation, yet there is a lack of surveillance documenting health conditions, health behaviors, and health care coverage among US fishermen. We used publicly available data sources to identify exposures and health outcomes common among fishermen. METHODS: We utilized the National Institute for Occupational Safety and Health–Worker Health Charts to estimate the prevalence of general exposures, psychosocial exposures, health behaviors, and health conditions from the national surveys National Health Interview Survey - Occupational Health Supplement (NHIS-OHS, 2015) and Behavioral Risk Factor Surveillance System (BRFSS) (2013–2015). We compared fishing workers with both agricultural workers and all-workers. RESULTS: Fishermen commonly reported general exposures, psychosocial exposures, non-standard work arrangements, frequent night shifts, and shift work. The prevalence of musculoskeletal conditions such as carpal tunnel syndrome (33%) and severe low-back pain (27%) was also high. Smoking (45%) and second-hand smoke exposure (25%) were widespread, and 21% reported no health care coverage. CONCLUSION: National household surveys such as NHIS-OHS, and BRFSS can be utilized to describe the health status of fishermen. This workforce would benefit from increased access to health care and health promotion programs. More comprehensive evaluations of existing data can help to identify occupation-specific health challenges.

Background We compared the relationship of past and contemporary sodium (Na) intake with cardiometabolic biomarkers. Methods and Results A total of 1191 participants' data from a randomized controlled trial in coastal Bangladesh were analyzed. Participants provided 24‐hour urine Na (24UNa) data for 5 monthly visits. Their fasting blood glucose, total cholesterol, triglycerides, high‐density lipoprotein, blood pressure, and 24‐hour urine protein were measured at the fifth visit. Participants' mean 24UNa over the first 4 visits was the past Na, and 24UNa of the fifth visit was the contemporary Na intake. We estimated the prevalence ratios of elevated cardiometabolic biomarkers and metabolic syndrome across 24UNa tertiles by multilevel logistic regression using participant‐, household‐, and community‐level random intercepts. Models were adjusted for age, sex, body mass index, smoking, physical activity, alcohol consumption, sleep hours, religion, and household wealth. Compared with participants in tertile 1 of past urine Na, those in tertile 3 had 1.46 (95% CI, 1.08–1.99) times higher prevalence of prediabetes or diabetes mellitus, 5.49 (95% CI, 2.73–11.01) times higher prevalence of large waist circumference, and 1.60 (95% CI, 1.04–2.46) times higher prevalence of metabolic syndrome. Compared with participants in tertile 1 of contemporary urine Na, those in tertile 3 had 1.93 (95% CI, 1.24–3.00) times higher prevalence of prediabetes or diabetes mellitus, 3.14 (95% CI, 1.45–6.83) times higher prevalence of proteinuria, and 2.23 (95% CI, 1.34–3.71) times higher prevalence of large waist circumference. Conclusions Both past and contemporary Na intakes were associated with higher cardiometabolic disease risk.

Background Drinking-water salinity has been associated with high blood pressure (BP) among communities in south-west coastal Bangladesh. We evaluated whether access to water from managed aquifer recharge (MAR)—a hydrogeological intervention to lower groundwater salinity by infiltrating rainwater into the aquifers—can reduce community BP. Methods We conducted a stepped-wedge cluster-randomized trial with five monthly visits between December 2016 and April 2017 in 16 communities. At each visit following baseline, four communities were randomized to access MAR water. Systolic BP was the primary outcome, measured during each visit using Omron® HEM–907 devices. We also measured participants’ 24-hour urinary sodium and households’ drinking- and cooking-water salinity each visit. We used multilevel regression models to estimate the effects of MAR-water access on participants’ BP. The primary analysis was intention-to-treat. Results In total, 2911 person-visits were conducted in communities randomized to have MAR-water access and 2834 in communities without MAR-water access. Households without MAR-water access predominantly used low-salinity pond water and 42% (range: 26–50% across visits) of households exclusively consumed MAR water when access was provided. Communities randomized to MAR-water access had 10.34 [95% confidence interval (CI): 1.11, 19.58] mmol/day higher mean urinary sodium, 1.96 (95% CI: 0.66, 3.26; p = 0.004) mmHg higher mean systolic BP and 1.44 (95% CI: 0.40, 2.48; p = 0.007) mmHg higher mean diastolic BP than communities without MAR-water access. Conclusions Our findings do not support the scale-up of MAR systems as a routine drinking-water source, since communities that shifted to MAR water from the lower-salinity pond-water source had higher urinary sodium and BP.

We evaluated the effectiveness of a sand barrier around latrine pits in reducing fecal indicator bacteria (FIB) leaching into shallow groundwater. We constructed 68 new offset single pit pour flush latrines in the Galachipa subdistrict of coastal Bangladesh. We randomly assigned 34 latrines to include a 50 cm thick sand barrier under and around the pit and 34 received no sand barrier. Four monitoring wells were constructed around each pit to collect water samples at baseline and subsequent nine follow-up visits over 24 months. Samples were tested using the IDEXX Colilert method to enumerate E. coli and thermotolerant coliforms most probable number (MPN). We determined the difference in mean log10MPN FIB counts/100 mL in monitoring well samples between latrines with and without a sand barrier using multilevel linear models and reported cluster robust standard error. The sand barrier latrine monitoring well samples had 0.38 mean log10MPN fewer E. coli (95% CI: 0.16, 0.59; p = 0.001) and 0.38 mean log10MPN f...

This study explores the associations of drinking rainwater with mineral intake and cardiometabolic health in the Bangladeshi population. We pooled 10030 person-visit data on drinking water sources, blood pressure (BP) and 24-h urine minerals. Fasting blood glucose (FBG) was measured in 3724 person-visits, and lipids in 1118 person-visits. We measured concentrations of sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) in 253 rainwater, 935 groundwater and 130 pond water samples. We used multilevel linear or gamma regression models with participant-, household- and community-level random intercepts to estimate the associations of rainwater consumption with urine minerals and cardiometabolic biomarkers. Rainwater samples had the lowest concentrations of Na, K, Ca and Mg. Rainwater drinkers had lower urine minerals than coastal groundwater drinkers: −13.42 (95% CI: −18.27, −8.57) mmol Na/24 h, −2.00 (95% CI: −3.16, −0.85) mmol K/24 h and −0.57 (95% CI: −1.02, −0.16) mmol Mg/24 h. The ratio of median 24-hour urinary Ca for rainwater versus coastal groundwater drinkers was 0.72 (95% CI: 0.64, 0.80). Rainwater drinkers had 2.15 (95% CI: 1.02, 3.27) mm Hg higher systolic BP, 1.82 (95% CI: 1.19, 2.54) mm Hg higher diastolic BP, 0.59 (95% CI: 0.17, 1.01) mmol/L higher FBG and −2.02 (95% CI: −5.85, 0.81) mg/dl change in high-density lipoprotein cholesterol compared with the coastal groundwater drinkers. Drinking rainwater was associated with worse cardiometabolic health measures, which may be due to the lower intake of salubrious Ca, Mg and K.

Managed aquifer recharge (MAR), a hydro-geological intervention designed to dilute groundwater salinity, pumps pond water treated through a slow sand filter into the underground aquifers. We evaluated the microbiological safety of the resulting MAR water at sites from three districts in southwest coastal Bangladesh. We collected monthly paired pond-MAR water samples from July 2016-June 2017 and enumerated fecal coliforms and E. coli using the IDEXX quanti-tray technique, by the most probable number (MPN) method. We used WHO risk categories for microbiological quality; no risk (10 MPN per 100 mL water). We estimated the difference in mean log10 MPN in pond and MAR water using linear mixed effect models with random intercepts and cluster adjusted robust standard error. Almost all pond water samples (292/299, 98%) had moderate- to high-risk level (>10 MPN) fecal coliforms and E. coli (283/299, 95%). In contrast, 81% (242/300) of MAR water samples had no or low risk level fecal coliforms (0-10 MPN), of which 60% (179/300) had no fecal coliforms. We detected no or low risk level E. coli in 94% (283/300) of MAR water samples of these 80% (240/300) had no E. coli. MAR samples had lower mean log10 MPN fecal coliforms (-2.37; 95% CI: -2.56, -2.19) and E. coli (-2.26; 95% CI: - 2.43, -2.09) than pond water; microbial reductions remained consistent during the wet (May-October) and dry seasons. MAR-systems provided water with reduced fecal indicator bacteria compared to infiltered pond water.

Background In the south-western coastal region of Bangladesh ground water, normally used for drinking, is excessively saline. Increased salinity in drinking water can have a range of adverse health impacts. Managed aquifer recharge (MAR) systems, which infiltrate rainwater and fresh pond water into aquifers, are adaptive strategies to deliver low-saline water to the affected communities. Several MAR systems have been piloted in these regions. The MAR pilot study demonstrated the potential for increasing freshwater availability and sustainable year-round drinking water supplies. The objective of this study was to identify MAR system management shortcomings and strengths to provide recommendations that are applicable for future MAR systems and engineering driven water management methods in low-income countries.Methods A qualitative study among the 18 pilot MAR communities with access to MAR systems since 2010 was conducted to assess perceptions of drinking MAR water and usage patterns. We conducted in-depth interviews (24), key informant interviews (2) and focus group discussions (3).Results More than half (13) of the respondents reported that drinking saline water causes diarrhea, dysentery, gastritis, digestive or abdominal disorders none described impact on blood pressure. More than two thirds (13/18) of current MAR users reported MAR as their preferred drinking water source. Almost half (11) reported that they were familiar with MAR but don’t understand how it works. A majority of respondents (17) considered MAR water safe because they thought there are no germs present. Nonetheless, respondents mentioned several problems including dissatisfaction with water quality (salinity/iron/smell/dirt in the water), and management (MAR sites found locked for most of the day). MAR installation and management staff and technical supervisors and caretakers thought that water quality was hampered by irregular water infiltration. They reported that management and maintenance issues were their primary concern, which were impeded by limited funds, as users do not pay regularly.Conclusions Though there is a demand for drinking water from MAR systems, the concerns about management related to finance, in addition to the amount collected are the greatest threat to system functionality and sustainability, which requires community-based solutions that will provide regular oversight and maintenance.

Background We compared the relationship between sodium (Na) intake and blood pressure when Na intake was estimated from first‐ and second‐morning spot urine samples using the INTERSALT (International Study on Salt and Blood Pressure) formula, versus directly measured 24‐hour samples. Methods and Results We collected 24‐hour urine and first‐ and second‐morning voids of 383 participants in coastal Bangladesh for 2 visits. We measured participants’ blood pressure using an Omron ® HEM–907 monitor. To assess the shape of the relationship between urinary Na and blood pressure, we created restricted cubic spline plots adjusted for age, sex, body mass index, smoking and alcohol consumption, physical activities, religion, sleep hours, and household wealth. To assess multicollinearity, we reported variance inflation factors, tolerances, and Leamer's and Klein's statistics following linear regression models. The mean daily urinary Na was 122 (SD 26) mmol/d for the first; 122 (SD 27) mmol/d for the second; and 134 (SD 70) mmol/d for the 24‐hour samples. The restricted cubic spline plots illustrated no association between first‐morning urinary Na and systolic blood pressure until the 90th percentile distribution followed by a downward relationship; a nonlinear inverse‐V‐shaped relationship between second‐morning urinary Na and systolic blood pressure; and a monotonic upward relationship between 24‐hour urinary Na and systolic blood pressure. We found no evidence of multicollinearity for the 24‐hour urinary Na model. Conclusions The urinary Na and systolic blood pressure relationship varied for 3 urinary Na measurements. Twenty‐four‐hour urinary Na captured more variability of Na intake compared with spot urine samples, and its regression models were not affected by multicollinearity.

Background: We assessed the association of groundwater chemicals with systolic blood pressure (SBP) and diastolic blood pressure (DBP). Methods: Blood pressure data for &ge, 35-year-olds were from the Bangladesh Demographic and Health Survey in 2011. Groundwater chemicals in 3534 well water samples from Bangladesh were measured by the British Geological Survey (BGS) in 1998&ndash, 1999. Participants who reported groundwater as their primary source of drinking water were assigned chemical measures from the nearest BGS well. Survey-adjusted linear regression methods were used to assess the association of each groundwater chemical with the log-transformed blood pressure of the participants. Models were adjusted for age, sex, body mass index, smoking status, geographical region, household wealth, rural or urban residence, and educational attainment, and further adjusted for all other groundwater chemicals. Results: One standard deviation (SD) increase in groundwater magnesium was associated with a 0.992 (95% confidence interval (CI): 0.986, 0.998) geometric mean ratio (GMR) of SBP and a 0.991 (95% CI: 0.985, 0.996) GMR of DBP when adjusted for covariates except groundwater chemicals. When additionally adjusted for groundwater chemicals, one SD increase in groundwater magnesium was associated with a 0.984 (95% CI: 0.972, 0.997) GMR of SBP and a 0.990 (95% CI: 0.979, 1.000) GMR of DBP. However, associations were attenuated following Bonferroni-correction for multiple chemical comparisons in the full-adjusted model. Groundwater concentrations of calcium, potassium, silicon, sulfate, barium, zinc, manganese, and iron were not associated with SBP or DBP in the full-adjusted models. Conclusions: Groundwater magnesium had a weak association with lower SBP and DBP of the participants.

Background Sodium (Na + ) in saline water may increase blood pressure ( BP ), but potassium (K + ), calcium (Ca 2+ ), and magnesium (Mg 2+ ) may lower BP . We assessed the association between drinking water salinity and population BP . Methods and Results We pooled 6487 BP measurements from 2 cohorts in coastal Bangladesh. We used multilevel linear models to estimate BP differences across water salinity categories: fresh water (electrical conductivity, BMI ), physical activity, smoking, household wealth, alcohol consumption, sleep hours, religion, and salt consumption. We evaluated the 24‐hour urinary minerals across salinity categories, and the associations between urinary minerals and BP using multilevel linear models. Compared with fresh water drinkers, mild‐salinity water drinkers had lower mean systolic BP (−1.55 [95% CI : −3.22–0.12] mm Hg) and lower mean diastolic BP (−1.26 [95% CI : −2.21–−0.32] mm Hg) adjusted models. The adjusted odds ratio among mild‐salinity water drinkers for stage 1 hypertension was 0.60 (95% CI : 0.43–0.84) and for stage 2 hypertension was 0.56 (95% CI : 0.46–0.89). Mild‐salinity water drinkers had high urinary Ca 2+ , and Mg 2+ , and both urinary Ca 2+ and Mg 2+ were associated with lower BP. Conclusions Drinking mild‐salinity water was associated with lower BP , which can be explained by higher intake of Ca 2+ and Mg 2+ through saline water.

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 ...

We analyzed data from a stepped wedge randomized trial to evaluate how urinary Na, K, Ca and Mg excretion are associated with the change in blood pressure (BP) among the adult population. We followed up a cohort of 1,191 participants (>20 years old) from 540 households in 16 communities of southwest coastal Bangladesh for five visits during December 2016 - April 2017 when they were exposed to high salinity drinking water. In all visits, we measured participants’ BP (N=5,746) and 24-hour urinary Na, K, Ca and Mg. We used multilevel linear regression models to determine the association among change in urinary excretion of Na, K, Ca and Mg with differences in mean systolic blood pressure (SBP) and diastolic blood pressure (DBP). Models included participant-, household-, and community-level random intercepts and were adjusted for age, sex, BMI, physical activity, smoking status, and household wealth. We restricted analysis among participants who had complete 24-hour urine collection based on measured versus expected urinary creatinine ratio of >=0.7 (N=5,103). The median urinary 24 hours Na excretion was 164 mmol, K was 34 mmol, Ca was 126 mg, and Mg was 83 mg in visit 1. The mean population SBP was 115.6 mmHg in visit 1 and 110.2 in visit 5, and the mean DBP was 68.9 mmHg in visit 1 and 65.9 in visit 5. Compared to visit 1, we found 85% higher urinary Ca in visit 3 and 57% higher urinary Mg in visit 5. We found 100 mmol per 24 hours increase in urinary Na was associated with 1.74 (95% CI: 0.85, 2.62) mmHg higher SBP and 0.51 (95% CI: -0.06, 1.08) mmHg higher DBP, and 50 mmol per 24 hours increase in urinary K was associated with 2.39 (95% CI: 0.84, 3.94) mmHg lower SBP and 0.79 (95% CI: -1.76, 0.17) mmHg lower DBP. We found 100 mg per 24 hours increase in urinary Ca was associated with 0.29 (95% CI: 0.02, 0.60) mmHg lower SBP and 0.32 (0.07, 0.57) mmHg lower DBP, and 100 mg per 24 hours increase in urinary Mg was associated with 1.09 (95% CI: 0.55, 1.64) mmHg lower SBP and 0.41 (0.07, 0.76) mmHg lower DBP. We found SBP lowering effect of urinary Mg increased if urinary Ca was lower (p = 0.048). We found urinary K, Ca, and Mg are associated with lower BP in coastal Bangladesh. Our results suggest a high intake of these beneficial minerals alongside Na reduction may successfully lower mean BP of the population.

IntroductionSaltwater intrusion and salinisation have contributed to drinking water scarcity in many coastal regions globally, leading to dependence on alternative sources for water supply. In southwest coastal Bangladesh, communities have few options but to drink brackish groundwater which has been associated with high blood pressure among the adult population, and pre-eclampsia and gestational hypertension among pregnant women. Managed aquifer recharge (MAR), the purposeful recharge of surface water or rainwater to aquifers to bring hydrological equilibrium, is a potential solution for salinity problem in southwest coastal Bangladesh by creating a freshwater lens within the brackish aquifer. Our study aims to evaluate whether consumption of MAR water improves human health, particularly by reducing blood pressure among communities in coastal Bangladesh.Methods and analysisThe study employs a stepped-wedge cluster-randomised controlled community trial design in 16 communities over five monthly visits. During each visit, we will collect data on participants’ source of drinking and cooking water and measure the salinity level and electrical conductivity of household stored water. At each visit, we will also measure the blood pressure of participants ≥20 years of age and pregnant women and collect urine samples for urinary sodium and protein measurements. We will use generalised linear mixed models to determine the association of access to MAR water on blood pressure of the participants.Ethics and disseminationThe study protocol has been reviewed and approved by the Institutional Review Boards of the International Centre for Diarrheal Disease Research, Bangladesh (icddr,b). Informed written consent will be taken from all the participants. This study is funded by Wellcome Trust, UK. The study findings will be disseminated to the government partners, at research conferences and in peer-reviewed journals.Trial registration numberNCT02746003; Pre-results.

In Dhaka, Bangladesh, the sensitivity and specificity of three human, three ruminant, and one avian source-associated QPCR microbial source tracking assays were evaluated using fecal samples collected on site. Ruminant-associated assays performed well, whereas the avian and human assays exhibited unacceptable cross-reactions with feces from other hosts. Subsequently, child hand rinses (n = 44) and floor sponge samples (n = 44) from low-income-households in Dhaka were assayed for fecal indicator bacteria (enterococci, Bacteroidales, and Escherichia coli) and a ruminant-associated bacterial target (BacR). Mean enterococci concentrations were of 100 most probable number (MPN)/2 hands and 1000 MPN/225 cm(2) floor. Mean concentrations of Bacteroidales were 10(6) copies/2 hands and 10(5) copies/225 cm(2) floor. E. coli were detected in a quarter of hand rinse and floor samples. BacR was detected in 18% of hand rinse and 27% of floor samples. Results suggest that effective household fecal management should account not only for human sources of contamination but also for animal sources. The poor performance of the human-associated assays in the study area calls into the question the feasibility of developing a human-associated marker in urban slum environments, where domestic animals are exposed to human feces that have been disposed in pits and open drains.

Background Drinking water salinity has contributed to scarcity of potable water in southwest coastal Bangladesh. Drinking saline water has been associated with high blood pressure among communities in southwest coastal Bangladesh, but the effect of water salinity on kidney health is unknown. We aimed to understand the association between drinking water salinity and urinary protein excretion from the baseline findings of a community-based stepped-wedge randomised trial. Methods We collected 24-h urine from 1185 participants from 532 households and 16 communities in three districts (Khulna, Satkhira, and Bagerhat) of southwest coastal Bangladesh between Nov 17, and Dec 21, 2016, and measured urinary sodium and total protein. We measured electrical conductivity in sampled households' stored drinking water. We estimated water chloride concentration by using a published conversion factor and then estimated daily sodium intake by drinking water assuming sodium ions will be coupled with chloride in water. Among normotensive participants who reported exclusively drinking household stored water, and did not report kidney or heart diseases or diabetes, we determined the effects of daily sodium intake by water and urinary sodium on total protein using hierarchical models accounting for household and community level clustering, and adjusted for age, sex and, weight. Findings Mean urinary sodium was 164 mmoL/24 h and total protein was 402 mg/24 h. Mean sodium intake through drinking water was 17 mmoL per day. For each 1000 μS/cm higher in drinking water electrical conductivity, there was a 8·2 mmoL/24 h (95% CI 5·3–11·1) higher excretion of 24-h urinary sodium. For each 10 mmoL increase in estimated daily sodium intake through drinking water, there was a 15·9 mg/24 h (95% CI 0·3–31·6) increase in total protein. We estimated a 62·9 mg/24 h (95% CI 29·7–96·1) increase in total protein for each 100 mmoL/24 h increase urinary sodium. We identified 37% participants that had mild proteinuria (total protein: 300–500 mg/24 h) and 20% had moderate or substantial proteinuria (total protein: >500 mg/24 h). Interpretation Drinking water sodium and urinary sodium were associated with increased protein excretion—a powerful marker for progressive kidney disease—in southwest coastal Bangladesh. Interventions aimed at lowering drinking water salinity could provide benefit to kidney health. Funding Wellcome Trust, UK.