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Gyimah R, Lebu S, Owusu-Frimpong I, Semiyaga S, Salzberg A, Manga M. Effluents from septic systems and impact on groundwater contamination: a systematic review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:62655-62675. [PMID: 39480579 DOI: 10.1007/s11356-024-35385-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Accepted: 10/18/2024] [Indexed: 11/02/2024]
Abstract
Globally, 2.2 billion people rely on groundwater for their water supply, and 2.8 billion use onsite sanitation systems for their sanitation needs. Groundwater contamination from septic systems is a critical public health concern, linked with diseases related to water sanitation and hygiene. Despite the severe impacts of septic systems on groundwater quality, comprehensive global studies remain limited. This study conducted a systematic review of articles published between 2012 and 2023 on topics related to septic systems and groundwater contamination, and 82 peer-reviewed articles met the inclusion criteria. The review identified key contaminants, including E.coli, nitrate, Enterococcus spp., total coliform, ammonium, phosphate, chlorides, and pharmaceuticals. Research on microbial indicators is more prevalent in Africa, while research on nutrients is common in North America. Research on organic contaminants including polyfluoroalkyl substances (PFAS), pharmaceuticals, and personal care products (PCPPs) is limited, particularly in low-and middle-income countries. Critical factors contributing to groundwater contamination include soil, hydrogeological conditions, climate, septic system maintenance and functioning, and septic density. The goal of this study was to comprehensively assess the extent of groundwater contamination resulting from septic system effluents by identifying the major contaminants typically found in affected groundwater sources and exploring the factors contributing to contamination. Identifying the major contaminants and factors related to groundwater contamination from septic systems is crucial for developing effective management strategies to protect groundwater sources.
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Affiliation(s)
- Rita Gyimah
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, Chapel Hill, NC, NC 27599, USA
| | - Sarah Lebu
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, Chapel Hill, NC, NC 27599, USA
| | - Isaac Owusu-Frimpong
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Swaib Semiyaga
- Department of Civil and Environmental Engineering, CEDAT, Makerere University, Kampala, Uganda
| | - Aaron Salzberg
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, Chapel Hill, NC, NC 27599, USA
| | - Musa Manga
- The Water Institute at UNC, Department of Environmental Sciences and Engineering, The Gillings School of Global Public Health, University of North Carolina at Chapel Hill, 4114 McGavran Hall, Campus Box # 7431, Chapel Hill, NC, NC 27599, USA.
- Department of Construction Economics and Management, CEDAT, Makerere University, Kampala, Uganda.
- Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, USA.
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Chavarria K, Batista J, Saltonstall K. Widespread occurrence of fecal indicator bacteria in oligotrophic tropical streams. Are common culture-based coliform tests appropriate? PeerJ 2024; 12:e18007. [PMID: 39253603 PMCID: PMC11382651 DOI: 10.7717/peerj.18007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 08/08/2024] [Indexed: 09/11/2024] Open
Abstract
Monitoring of stream water quality is a key element of water resource management worldwide, but methods that are commonly used in temperate habitats may not be appropriate in humid tropical systems. We assessed the influence of four land uses on microbial water quality in 21 streams in the Panama Canal Watershed over a one-year period, using a common culture-based fecal indicator test and 16S rDNA metabarcoding. Each stream was located within one of four land uses: mature forest, secondary forest, silvopasture, and traditional cattle pasture. Culturing detected total coliforms and Escherichia coli across all sites but found no significant differences in concentrations between land uses. However, 16S rDNA metabarcoding revealed variability in the abundance of coliforms across land uses and several genera that can cause false positives in culture-based tests. Our results indicate that culture-based fecal indicator bacteria tests targeting coliforms may be poor indicators of fecal contamination in Neotropical oligotrophic streams and suggest that tests targeting members of the Bacteroidales would provide a more reliable indication of fecal contamination.
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Affiliation(s)
- Karina Chavarria
- Smithsonian Tropical Research Institute, Panama City, Panama
- Department of Civil and Environmental Engineering, University of Massachusetts at Amherst, Amherst, MA, United States of America
| | - Jorge Batista
- Smithsonian Tropical Research Institute, Panama City, Panama
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Nguyen AT, Grembi JA, Riviere M, Barratt Heitmann G, Hutson WD, Athni TS, Patil A, Ercumen A, Lin A, Crider Y, Mertens A, Unicomb L, Rahman M, Luby SP, Arnold BF, Benjamin-Chung J. Influence of Temperature and Precipitation on the Effectiveness of Water, Sanitation, and Handwashing Interventions against Childhood Diarrheal Disease in Rural Bangladesh: A Reanalysis of the WASH Benefits Bangladesh Trial. ENVIRONMENTAL HEALTH PERSPECTIVES 2024; 132:47006. [PMID: 38602833 PMCID: PMC11008709 DOI: 10.1289/ehp13807] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 03/08/2024] [Accepted: 03/13/2024] [Indexed: 04/13/2024]
Abstract
BACKGROUND Diarrheal disease is a leading cause of childhood morbidity and mortality globally. Household water, sanitation, and handwashing (WASH) interventions can reduce exposure to diarrhea-causing pathogens, but meteorological factors may impact their effectiveness. Information about effect heterogeneity under different weather conditions is critical to refining these targeted interventions. OBJECTIVES We aimed to determine whether temperature and precipitation modified the effect of low-cost, point-of-use WASH interventions on child diarrhea. METHODS We analyzed data from a trial in rural Bangladesh that compared child diarrhea prevalence between clusters (N = 720 ) that were randomized to different WASH interventions between 2012 and 2016 (NCT01590095). We matched temperature and precipitation measurements to diarrhea outcomes (N = 12,440 measurements, 6,921 children) by geographic coordinates and date. We estimated prevalence ratios (PRs) using generative additive models and targeted maximum likelihood estimation to assess the effectiveness of each WASH intervention under different weather conditions. RESULTS Generally, WASH interventions most effectively prevented diarrhea during monsoon season, particularly following weeks with heavy rain or high temperatures. The PR for diarrhea in the WASH interventions group compared with the control group was 0.49 (95% CI: 0.35, 0.68) after 1 d of heavy rainfall, with a less-protective effect [PR = 0.87 (95% CI: 0.60, 1.25)] when there were no days with heavy rainfall. Similarly, the PR for diarrhea in the WASH intervention group compared with the control group was 0.60 (95% CI: 0.48, 0.75) following above-median temperatures vs. 0.91 (95% CI: 0.61, 1.35) following below-median temperatures. The influence of precipitation and temperature varied by intervention type; for precipitation, the largest differences in effectiveness were for the sanitation and combined WASH interventions. DISCUSSION WASH intervention effectiveness was strongly influenced by precipitation and temperature, and nearly all protective effects were observed during the rainy season. Future implementation of these interventions should consider local environmental conditions to maximize effectiveness, including targeted efforts to maintain latrines and promote community adoption ahead of monsoon seasons. https://doi.org/10.1289/EHP13807.
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Affiliation(s)
- Anna T. Nguyen
- Department of Epidemiology and Population Health, Stanford University, Stanford, California, USA
| | - Jessica A. Grembi
- Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, USA
| | - Marie Riviere
- Department of Epidemiology and Population Health, Stanford University, Stanford, California, USA
| | | | - William D. Hutson
- Brown School, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Tejas S. Athni
- Department of Epidemiology and Population Health, Stanford University, Stanford, California, USA
- Harvard Medical School, Boston, Massachusetts, USA
| | - Arusha Patil
- Department of Epidemiology and Population Health, Stanford University, Stanford, California, USA
| | - Ayse Ercumen
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina, USA
| | - Audrie Lin
- Department of Microbiology and Environmental Toxicology, University of California, Santa Cruz, Santa Cruz, California, USA
| | - Yoshika Crider
- King Center on Global Development, Stanford University, Stanford, California, USA
| | - Andrew Mertens
- Division of Epidemiology and Biostatistics, University of California, Berkeley, Berkeley, California, USA
| | - Leanne Unicomb
- Environmental Health and WASH, Health System and Population Studies Division, ICDDR,B, Dhaka, Bangladesh
| | - Mahbubur Rahman
- Environmental Health and WASH, Health System and Population Studies Division, ICDDR,B, Dhaka, Bangladesh
| | - Stephen P. Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, USA
| | - Benjamin F. Arnold
- Francis I. Proctor Foundation, University of California, San Francisco, San Francisco, California, USA
| | - Jade Benjamin-Chung
- Department of Epidemiology and Population Health, Stanford University, Stanford, California, USA
- Chan Zuckerberg Biohub, San Francisco, California, USA
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Nipa NJ, Aktar N, Hira HM, Akter F, Jahan D, Islam S, Etando A, Abdullah A, Chowdhury K, Ahmad R, Haq A, Haque M. Intestinal Parasitic Infections Among Pediatric Patients in a Metropolitan City of Bangladesh With Emphasis on Cryptosporidiosis. Cureus 2022; 14:e26927. [PMID: 35865179 PMCID: PMC9293268 DOI: 10.7759/cureus.26927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2022] [Indexed: 11/26/2022] Open
Abstract
Introduction Gastrointestinal parasitic infections are one of the global health concerns in developing countries like Bangladesh. Among them, Cryptosporidium spp. plays an essential role in causing diarrhea, malnutrition, and poor cognitive function, especially in children. This study was conducted to identify the frequency of Cryptosporidium cases and other parasitic agents. Methods A cross-sectional observational study was conducted among 219 hospitalized children with diarrhea. The conventional microscopic technique was applied for parasitic detection. Particular staining (modified Ziehl-Neelsen) procedure was performed to identify oocysts of Cryptosporidium spp. A polymerase chain reaction (PCR) was performed to determine the SSU rRNA and gp60 gene of Cryptosporidium. Results Cysts of Giardia duodenalis (2.3%), ova of Ascaris lumbricoides (1.4%,), Trichuris trichiura (0.5%), and both A. lumbricoides and T. trichiura (0.9%) were identified in samples through wet mount preparation. The distribution of Cryptosporidium spp. as detected by the staining method and nested PCR was 1.4% and 4.1%, respectively. Conclusion Factors independently associated with Cryptosporidium infection are unsafe water, lack of regular hand washing, and insufficiency of exclusive breastfeeding. This study reports, presumably for the first time, the detection of Cryptosporidium oocysts in Chattogram metropolitan city of Bangladesh.
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Affiliation(s)
| | - Nasima Aktar
- Microbiology, Chittagong Medical College, Chattogram, BGD
| | - Hasina M Hira
- Community Medicine, Chittagong Medical College, Chattogram, BGD
| | - Farhana Akter
- Endocrinology and Diabetes, Chittagong Medical College, Chattogram, BGD
| | | | | | - Ayukafangha Etando
- Medical Laboratory Sciences, Faculty of Health Sciences, Eswatini Medical Christian University, Mbabane, SWZ
| | - Adnan Abdullah
- Occupational Medicine, Faculty of Medicine and Defence Health, Universiti Pertahanan Nasional Malaysia (National Defence University of Malaysia), Kuala Lumpur, MYS
| | - Kona Chowdhury
- Pediatrics, Gonoshasthaya Samaj Vittik Medical College, Savar, BGD
| | - Rahnuma Ahmad
- Physiology, Medical College for Women and Hospital, Dhaka, BGD
| | - Ahsanul Haq
- Statistics, Gonoshasthaya - RNA Biotech Limited, Savar, BGD
| | - Mainul Haque
- Pharmacology and Therapeutics, Universiti Pertahanan Nasional Malaysia (National Defence University of Malaysia), Kuala Lumpur, MYS
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5
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Lebel L, Aung N, Long CTM, Siharath P, Lebel P, Navy H, Hoanh CT, Lebel B. Stakeholder Perspectives on COVID-19 and Household Water Access in Vulnerable Communities in the Mekong Region. ENVIRONMENTAL MANAGEMENT 2022; 69:1066-1077. [PMID: 35237852 PMCID: PMC8890463 DOI: 10.1007/s00267-022-01616-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 02/15/2022] [Indexed: 06/14/2023]
Abstract
The COVID-19 pandemic has underlined the importance of safe access to sufficient clean water in vulnerable communities, renewing interest in water, sanitation and hygiene (WASH) programs and related targets under Sustainable Development Goal 6 (SDG 6). The purpose of this study was to better understand the obstacles to water access in vulnerable communities and identify ways they might be addressed in five countries in the Mekong Region (Cambodia, Laos, Myanmar, Thailand, Vietnam). To this end, qualitative interviews with 50 government officials and development or health experts were complimented with a quantitative survey of the experiences and views of individuals in 15 vulnerable communities. There were several key findings. First, difficulties in accessing sufficient clean water for drinking and hygiene persist in certain vulnerable communities, including informal urban settlements, remote minority villages, and migrant worker camps. Second, limited rights, high prices, and remote locations were common obstacles to household access to improved water sources. Third, seasonal differences in the availability of clean water, alongside other disruptions to supply such as restrictions on movement in COVID-19 responses, drove households towards lower quality sources. Fourth, there are multiple threats to water quality from source to consumption that should be addressed by monitoring, treatment, and watershed protection. Fifth, stakeholder groups differ from each other and residents of vulnerable communities regarding the significance of water access, supply and quality difficulties, and how they should be addressed. The paper ends with a set of program suggestions addressing these water-related difficulties.
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Affiliation(s)
- Louis Lebel
- Unit for Social and Environmental Research, Department of Social Science and Development, Faculty of Social Sciences, Chiang Mai University, Chiang Mai, Thailand
| | | | - Chau Thi Minh Long
- Western Highlands Agriculture and Forestry Science Institute, Dak Lak, Vietnam
| | - Phoummixay Siharath
- Department of Environmental Engineering, Faculty of Engineering, National University of Laos, Vientiane, Lao PDR
| | - Phimphakan Lebel
- Unit for Social and Environmental Research, Department of Social Science and Development, Faculty of Social Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Hap Navy
- Inland Fisheries Research and Development Institute, Fisheries Administration, Ministry of Agriculture, Forestry and Fisheries, Phnom Penh, Cambodia
| | - Chu Thai Hoanh
- International Water Management Institute, Regional Office for Southeast Asia, Vientiane, Lao PDR
| | - Boripat Lebel
- Unit for Social and Environmental Research, Department of Social Science and Development, Faculty of Social Sciences, Chiang Mai University, Chiang Mai, Thailand.
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Socio-Economic Aspects of Centralized Wastewater System for Rural Settlement under Conditions of Eastern Poland. WATER 2022. [DOI: 10.3390/w14101667] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
This paper presents a case study concerning multivariate analysis, including social and financial aspects, as well as environmental impacts, of the organized sanitation development under conditions of the selected rural settlement in Poland. Three technologically up-to-date variants of sanitary sewerage network concepts with the different assumed sewage transport, i.e., pressure, pressure-gravity and gravity, were proposed together with the investment and operation and maintenance costs estimation. The willingness-to-accept (WTA) and willingness-to-pay (WTP) survey was used to analyze the level of social acceptance and involvement. The financial analysis covered two economic and cost-efficiency dynamic indicators, benefits–costs ratio (BCR) and dynamic generation cost (DGC), commonly used to support the decision-making process. The environmental aspects were assessed by the possible anthropopressure caused by sewerage leakage and odor emissions. Results of the WTA and WTP survey presented a significant level of acceptance and involvement of the local population to sustain the improved sanitation. The determined values of DGC indicated low cost-efficiency of the gravity system, while obtained values of BCR for all variants and the actual regional sewage fees showed the low profitability of improved sanitation, i.e., BCR < 1.0. All studied sanitation systems were assessed positively due to their environmental impacts. The performed studies showed that, despite the declared willingness to accept the organized sanitation and to pay the sewage fees, the economical sustainability of the proposed designs is doubtful over the longer time duration due to the significant capital and operation costs affecting the sewerage payment value.
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7
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Contreras JD, Islam M, Mertens A, Pickering AJ, Kwong LH, Arnold BF, Benjamin-Chung J, Hubbard AE, Alam M, Sen D, Islam S, Rahman M, Unicomb L, Luby SP, Colford JM, Ercumen A. Longitudinal Effects of a Sanitation Intervention on Environmental Fecal Contamination in a Cluster-Randomized Controlled Trial in Rural Bangladesh. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:8169-8179. [PMID: 34086447 PMCID: PMC8213058 DOI: 10.1021/acs.est.1c01114] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/18/2021] [Accepted: 05/20/2021] [Indexed: 05/06/2023]
Abstract
Household latrine access generally is not associated with reduced fecal contamination in the environment, but its long-term effectiveness has not been measured. We conducted an environmental assessment nested within the WASH Benefits Bangladesh randomized controlled trial (NCT01590095). We quantified E. coli and fecal coliforms in samples of stored drinking water, child hands, mother hands, soil, and food among a random sample of households from the sanitation and control arms of the trial. Samples were collected during eight quarterly visits approximately 1-3.5 years after intervention initiation. Overall, there were no substantial differences in environmental fecal contamination between households enrolled in the sanitation and control arms. Statistically significant reductions were found in stored water and child hands after pooling across sampling rounds, but the effects were small and not consistent across rounds. In addition, we assessed potential effect modification of intervention effects by follow-up time, season, wealth, community-level latrine density and coverage, population density, and domestic animal ownership. While the intervention had statistically significant effects within some subgroups, there were no consistent patterns of effect modification. Our findings support a growing consensus that on-site latrines are insufficient to prevent fecal contamination in the rural household environment.
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Affiliation(s)
- Jesse D. Contreras
- Department
of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Mahfuza Islam
- Environmental
Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Andrew Mertens
- Division
of Epidemiology and Biostatistics, School
of Public Health, University of California, Berkeley, California 94720, United States
| | - Amy J. Pickering
- Department
of Civil and Environmental Engineering, University of California, Berkeley, California 94720, United States
| | - Laura H. Kwong
- Woods
Institute for the Environment, Stanford
University, Stanford, California 94305, United States
| | - Benjamin F. Arnold
- Francis I.
Proctor Foundation, University of California, San Francisco, California 94143, United States
| | - Jade Benjamin-Chung
- Division
of Epidemiology and Biostatistics, School
of Public Health, University of California, Berkeley, California 94720, United States
| | - Alan E. Hubbard
- Division
of Epidemiology and Biostatistics, School
of Public Health, University of California, Berkeley, California 94720, United States
| | - Mahfuja Alam
- Environmental
Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Debashis Sen
- Environmental
Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Sharmin Islam
- Environmental
Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Mahbubur Rahman
- Environmental
Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Leanne Unicomb
- Environmental
Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research Bangladesh, Dhaka 1212, Bangladesh
| | - Stephen P. Luby
- Woods
Institute for the Environment, Stanford
University, Stanford, California 94305, United States
| | - John M. Colford
- Division
of Epidemiology and Biostatistics, School
of Public Health, University of California, Berkeley, California 94720, United States
| | - Ayse Ercumen
- Department
of Forestry and Environmental Resources, North Carolina State University, Raleigh, North Carolina 27695, United States
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Pak HY, Chuah CJ, Tan ML, Yong EL, Snyder SA. A framework for assessing the adequacy of Water Quality Index - Quantifying parameter sensitivity and uncertainties in missing values distribution. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 751:141982. [PMID: 33181998 DOI: 10.1016/j.scitotenv.2020.141982] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/06/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
Water quality monitoring is a pillar in water resource management, but it can be resource intensive, especially for developing countries with limited resources. As such, Water Quality Indices (WQI) are developed to summarise general water quality, but efforts to assess the utility, flexibility, and practicality of WQI have been limited. In this study, we introduced an additional step to the traditional WQI development framework by introducing an adjusted form of WQI (WQIADJUSTED) to handle missing values, and capitalise on the remaining available information for the development of a WQI. A Sub-WQI was also developed to address local water quality conditions. WQI results (weighted and non-weighted) developed using different parameter optimisation methods, namely Multivariate Linear Regression and Principal Component Analysis were compared. To build upon the current framework, a new procedure was developed to assess the adequacy of WQI based on the sensitivity analysis of parameters and uncertainties associated with each parameter's missing values distribution. The number of observations needed for the development of a robust WQI was optimised with respect to user-defined acceptable change in WQI, based on Monte Carlo probabilistic simulation. The Johor River Basin (JRB), Malaysia is used as a case-study for the application of this new framework. The JRB serves as an important resource for Johor, one of the most populous state in Malaysia, and Singapore, a country south of Johor. WQIMLR performed better in explaining the general water quality than WQIPCA for weighted water quality parameters. Optimisation of sampling frequency revealed that around 130 samples will be required if a 2% change in WQI can be tolerated. The results (specific to the JRB) also revealed that total coliform is the most sensitivity parameter to missing values, and the distribution of sensitive parameters are similar for both WQINON-ADJUSTED and WQIADJUSTED.
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Affiliation(s)
- Hui Ying Pak
- Nanyang Environment And Water Research Institute (NEWRI), Nanyang Technological University of Singapore, 1 Cleantech Loop, 637141, Singapore
| | - C Joon Chuah
- Nanyang Environment And Water Research Institute (NEWRI), Nanyang Technological University of Singapore, 1 Cleantech Loop, 637141, Singapore; Tembusu College, National University of Singapore, 28 College Ave E, #B1-01, 138598, Singapore
| | - Mou Leong Tan
- Geography Section, School of Humanities, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Ee Ling Yong
- Department of Environmental Engineering, Faculty of Civil Engineering, Universiti Teknologi Malaysia (UTM), 81310, Johor, Malaysia
| | - Shane A Snyder
- Nanyang Environment And Water Research Institute (NEWRI), Nanyang Technological University of Singapore, 1 Cleantech Loop, 637141, Singapore.
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Effect of Inter-Observer Variation on the Association between Contamination Hazards and the Microbiological Quality of Water Sources: A Longitudinal Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17249192. [PMID: 33317003 PMCID: PMC7764753 DOI: 10.3390/ijerph17249192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 11/26/2020] [Accepted: 12/02/2020] [Indexed: 11/29/2022]
Abstract
Sanitary risk inspection protocols are often used to identify contamination hazards at water sources; however, different observers sometimes struggle to record hazards consistently. This study aimed to assess the effect of inter-observer variation in hazard observations on the strength of relationships between observed hazards and the bacterial contamination of water sources, particularly relationships with animal-related hazards. In a longitudinal study, five surveyors independently recorded hazards at 93 water sources used by 234 households in Siaya County, Kenya, in both wet and dry seasons. One surveyor collected samples from sources for subsequent Escherichia coli and intestinal enterococci testing. The relationship between each surveyor’s hazard observations and high bacterial contamination was examined using logistic regression. After controlling for water source type and preceding rainfall; percentage scores for animal-related hazards were significantly related to high contamination with enterococci and E. coli for one surveyor (odds ratio 1.02; 95% confidence intervals 1.00–1.03 for both parameters), but not for the remaining four surveyors. The relationship between observed contamination hazards and the microbiological contamination of water sources is sensitive to variation in hazard recording between surveyors. Sanitary risk protocols should be designed to enable robust and consistent observation of hazards.
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10
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Kurwadkar S. Occurrence and distribution of organic and inorganic pollutants in groundwater. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2019; 91:1001-1008. [PMID: 31230394 DOI: 10.1002/wer.1166] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/13/2019] [Accepted: 06/16/2019] [Indexed: 06/09/2023]
Abstract
Depletion of groundwater resources and continued decline in overall groundwater quality is a cause of concern because large human population around the world uses groundwater as a source of drinking water. This paper presents a comprehensive review of studies published in the year 2018 that documented issues of groundwater pollution, sources, and distribution reported from across the world due to anthropogenic, hydroclimatogical, and natural processes. Groundwater pollution due to organic contaminants focuses particularly on pesticides, herbicides, and contaminants of emerging concern. Pollution due to inorganic pollutants such as arsenic and other heavy metals is also reviewed with particular emphasis on regions that have reported a significantly higher incidence of these pollutants in groundwater. A compilation of various studies is also included in the review paper that showed increased incidences of waterborne illnesses due to fecal and microbial contamination due to poor sanitary practices. Reviews of groundwater contaminants such as fluoride and nitrate are included to provide readers a holistic understanding of groundwater pollution problem around the world. PRACTITIONER POINTS: Groundwater pollution issues during 2018 are reviewed and documented. Occurrence of organic and inorganic pollutants in groundwater is reported. Groundwater pollution vulnerability remains a critical issue.
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Affiliation(s)
- Sudarshan Kurwadkar
- Department of Civil and Environmental Engineering, California State University, Fullerton, California, USA
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11
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Ansari FA, Khan AA, Mahmood R. Ameliorative effect of carnosine and N-acetylcysteine against sodium nitrite induced nephrotoxicity in rats. J Cell Biochem 2019; 120:7032-7044. [PMID: 30368897 DOI: 10.1002/jcb.27971] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 10/04/2018] [Indexed: 01/24/2023]
Abstract
The widespread use of sodium nitrite (NaNO2 ) for various industrial purposes has increased human exposure to alarmingly high levels of nitrate/nitrite. Because NaNO 2 is a strong oxidizing agent, induction of oxidative stress is one of the mechanisms by which it can exert toxicity in humans and animals. We have investigated the possible protection offered by carnosine (CAR) and N-acetylcysteine (NAC) against NaNO 2 -induced nephrotoxicity in rats. Animals orally received CAR at 100 mg/kg body weight/d for seven days or NAC at 100 mg/kg body weight/d for five days followed by a single oral dose of NaNO 2 at 60 mg/kg body weight. The rats were killed after 24 hours, and the kidneys were removed and processed for various analyses. NaNO 2 induced oxidative stress in kidneys, as shown by the decreased activities of antioxidant defense, brush border membrane, and metabolic enzymes. DNA-protein crosslinking and DNA fragmentation were also observed. CAR/NAC pretreatment significantly protected the kidney against these biochemical alterations. Histological studies supported these findings, showing kidney damage in NaNO 2 -treated animals and reduced tissue impairment in the combination groups. The protection offered by CAR and NAC against NaNO 2 -induced damage, and their nontoxic nature, makes them potential therapeutic agents against nitrite-induced nephrotoxicity.
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Affiliation(s)
- Fariheen Aisha Ansari
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, India
| | - Aijaz Ahmed Khan
- Department of Anatomy, Faculty of Medicine, J.N. Medical College, Aligarh Muslim University, Aligarh, UP, India
| | - Riaz Mahmood
- Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh, UP, India
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12
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Goh SG, Saeidi N, Gu X, Vergara GGR, Liang L, Fang H, Kitajima M, Kushmaro A, Gin KYH. Occurrence of microbial indicators, pathogenic bacteria and viruses in tropical surface waters subject to contrasting land use. WATER RESEARCH 2019; 150:200-215. [PMID: 30528917 PMCID: PMC7112093 DOI: 10.1016/j.watres.2018.11.058] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 11/18/2018] [Accepted: 11/19/2018] [Indexed: 05/21/2023]
Abstract
Fecal indicator bacteria, such as Escherichia coli (E.coli) and Enterococcus, have been widely used to indicate the presence of pathogens. However, the suitability of fecal indicator bacteria to represent health risks is still being challenged, particularly in tropical aquatic environments. The objective of this study is to understand the occurrence and prevalence of indicators and pathogens in areas with contrasting land use, as well as to identify the major correlations between indicators, pathogens and environmental parameters. The spatial and temporal variation of indicators and pathogens was studied to examine the distribution patterns for areas with different land use, and the impact of seasonal changes on microbial populations. A total of 234 water samples were sampled for two years from reservoirs and their tributaries, and tested for fecal indicator bacteria, coliphages, human specific markers, pathogenic bacteria and viruses. The prevalence of indicators and pathogens in reservoirs were generally low, while relatively high concentrations were observed in tributaries to varying degrees. Of the enteric viruses, norovirus GII was among the most prevalent and had the highest concentration. Although strong correlations were found between indicators, only relatively weak correlations were found between indicators and pathogens. The results in this study showed that none of the bacteria/phage indicators were universal predictors for pathogens. Inclusion of the alternative indicators, Methanobrevibacter smithii, Bacteroides and human polyomaviruses (HPyVs) to monitoring programs could help to determine whether the fecal source was human. The microbial distribution patterns allow the classification of sampling sites to different clusters and thus, help to identify sites which have poor water quality. This approach will be useful for water quality management to pinpoint factors that influence water quality and help to prioritize sites for restoration of water quality.
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Affiliation(s)
- Shin Giek Goh
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore
| | - Nazanin Saeidi
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore
| | - Xiaoqiong Gu
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore
| | | | - Liang Liang
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore
| | - Haoming Fang
- NUS Environmental Research Institute, National University of Singapore, Singapore
| | - Masaaki Kitajima
- Division of Environmental Engineering, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Ariel Kushmaro
- School of Material Science and Engineering, Nanyang Technological University, Singapore
| | - Karina Yew-Hoong Gin
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore; NUS Environmental Research Institute, National University of Singapore, Singapore.
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13
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Nawrocki CC, Kiatsopit N, Namsanor J, Sithithaworn P, Carlton EJ. Culture of fecal indicator bacteria from snail intestinal tubes as a tool for assessing the risk of Opisthorchis viverrini infection in Bithynia snail habitat. Parasit Vectors 2019; 12:66. [PMID: 30700304 PMCID: PMC6354346 DOI: 10.1186/s13071-019-3313-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 01/13/2019] [Indexed: 11/10/2022] Open
Abstract
Background Like many trematodes of human health significance, the carcinogenic liver fluke, Opisthorchis viverrini, is spread via fecal contamination of snail habitat. Methods for assessing snail exposure to fecal waste can improve our ability to identify snail infection hotspots and potential sources of snail infections. We evaluated the feasibility of culturing fecal indicator bacteria from Bithynia snail intestinal tubes as a method for assessing snail exposure to fecal waste. Snails and water samples were collected from a site with a historically high prevalence of O. viverrini infected snails (“hotspot” site) and a site with historically no infected snails (“non-hotspot” site) on two sampling days. Snails were tested for O. viverrini and a stratified random sample of snails from each site was selected for intestinal tube removal and culture of gut contents for the fecal indicator bacteria, Escherichia coli. Water samples were tested for E. coli and nearby households were surveyed to assess sources of fecal contamination. Results At the hotspot site, 26 of 2833 Bithynia siamensis goniomphalos snails were infected with O. viverrini compared to 0 of 1421 snails at the non-hotspot site. A total of 186 snails were dissected and cultured. Escherichia coli were detected in the guts of 20% of uninfected snails, 4% of O. viverrini-positive snails and 8% of snails not examined for cercarial infection at the hotspot site. Only one of 75 snails from the non-hotspot site was positive for E. coli. Accounting for sampling weights, snails at the hotspot site were more likely to have gut E. coli than snails from the non-hotspot site. The concentration of fecal indicator bacteria in surface water was higher at the hotspot vs non-hotspot site on only the first sampling day. Conclusions Fecal indicator bacteria can be detected in the intestinal tubes of Bithynia snails. The presence of fecal indicator bacteria in Bithynia snail guts may indicate risk of O. viverrini infection in snail populations. This method has the potential to aid in identifying locations and time windows of peak snail infection risk and may be applicable to other trematodes of human-health significance. Electronic supplementary material The online version of this article (10.1186/s13071-019-3313-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Courtney C Nawrocki
- Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Nadda Kiatsopit
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,Cholangiocarcinoma Research Institute, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Jutamas Namsanor
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,Cholangiocarcinoma Research Institute, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Paiboon Sithithaworn
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.,Cholangiocarcinoma Research Institute, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Elizabeth J Carlton
- Department of Environmental and Occupational Health, Colorado School of Public Health, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA.
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