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Asefa EM, Damtew YT, Mengistu DA, Tolera ST, Dugasa FF, Berhanu A, Enoe J, Ober J, Teklu BM, Weldemariam ED. Heavy metals in Ethiopian drinking water and public health risks: Insights from nationwide and regional analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 947:174527. [PMID: 38977100 DOI: 10.1016/j.scitotenv.2024.174527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 07/03/2024] [Accepted: 07/03/2024] [Indexed: 07/10/2024]
Abstract
The ambitious sustainable development goal (SDG) 6 of the United Nations, which aims to achieve universal access to safe water and sanitation by 2030, remains elusive for many developing countries like Ethiopia. This is often due to a multitude of intricate factors, including the escalating degradation of water quality. Here, we present a comprehensive nationwide and regional analysis of heavy metal pollution in drinking water sources and the associated human health risks in Ethiopia based on a dataset of 11 heavy metal concentrations (n = 975) collated from available studies. Results indicate significant variations in heavy metal pollution in drinking water sources in Ethiopia, with 44 % of the total concentration exceeding maximum permissible limits. The mean concentrations were ranked as follows: Pb (1.92 mg/L) > Zn (1.25 mg/L) > Fe (0.56 mg/L) > Mn (0.43 mg/L) > Cu (0.40 mg/L) > Co (0.30 mg/L) > As (0.12 mg/L) > Ni (0.12 mg/L) > Cr (0.10 mg/L) > Cd (0.06 mg/L) > Hg (0.04 mg/L). We found that children are more vulnerable to non-carcinogenic health risks than adults, with the highest hazard quotient (HQ) exceedances of up to a factor of 1823 and 762, respectively. Furthermore, a Monte Carlo-based probabilistic risk assessment highlighted significant concerns regarding co-exposure to multiple heavy metals. The measured concentrations, ingestion rates, and exposure frequencies were identified as sensitive parameters. Overall, a higher risk was attributed to Pb and As, with river drinking water sources and the Tigray region requiring immediate mitigation measures. In conclusion, the findings emphasize the urgent need to test and purify water before consumption and to implement effective public health interventions. Furthermore, a multifaceted approach including regular monitoring, source protection, and proper waste management is recommended to expedite the achievement of SDGs and promote water sustainability in resource-limited Ethiopia and sub-Saharan Africa.
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Affiliation(s)
- Elsai Mati Asefa
- School of Environmental Health, College of Health and Medical Sciences, Haramaya University, 235 Harar, Ethiopia.
| | - Yohannes Tefera Damtew
- School of Environmental Health, College of Health and Medical Sciences, Haramaya University, 235 Harar, Ethiopia; School of Public Health, The University of Adelaide, Adelaide 5005, Australia
| | - Dechasa Adare Mengistu
- School of Environmental Health, College of Health and Medical Sciences, Haramaya University, 235 Harar, Ethiopia
| | - Sina Temesgen Tolera
- School of Environmental Health, College of Health and Medical Sciences, Haramaya University, 235 Harar, Ethiopia
| | - Faye Fekede Dugasa
- School of Pharmacy, College of Health and Medical Sciences, Haramaya University, 235 Harar, Ethiopia
| | - Abdi Berhanu
- School of Medicine, College of Health and Medical Sciences, Haramaya University, 235 Harar, Ethiopia
| | - Jerry Enoe
- Department of Geomatics Engineering and Land Management, The University of the West Indies, St. Augustine, Trinidad and Tobago
| | - Józef Ober
- Department of Applied Social Sciences, Faculty of Organization and Management, Silesian University of Technology, Roosevelta 26-28, 41-800 Zabrze, Poland
| | - Berhan M Teklu
- Plant Quarantine and Regulatory Lead Executive, Ethiopian Agricultural Authority, 313003 Addis Ababa, Ethiopia
| | - Ermias Deribe Weldemariam
- Department of Environmental Management, Faculty of Urban Development Studies, Kotebe University of Education, 31248 Addis Ababa, Ethiopia
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Sultana Z, Rehman MYA, Khan HK, Malik RN. Health risk assessment associated with heavy metals through fractioned dust from coal and chromite mines in Pakistan. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:1617-1633. [PMID: 35552963 DOI: 10.1007/s10653-022-01285-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 04/19/2022] [Indexed: 06/15/2023]
Abstract
Heavy metals exposure through dust emissions pose a health risk to workers in coal and chromite mines. The processes involved in mining are noteworthy for the generation of heavy metal-contaminated dust which causes human health implications, especially to the workers that are mainly exposed to such toxins. This study determined pollution levels in coal and chromite mines and calculated the health risk of workers being exposed to heavy metal-contaminated dust. We used fractioned dust with particle sizes < 75, 75-106, and 107-150 µm to assess the pollution levels, anthropogenic impacts, geo-accumulation index, and enrichment factor for selected coal and chromite mines. Through a probabilistic approach, Monte Carlo simulations were used to determine health risks. The findings revealed that the smallest size dust fraction (< 75 μm) contained the highest metal concentrations. Ingestion was considered a prominent exposure route contributing to health risk. In the dust fraction (< 75 μm), chromite mines exhibited the highest Cr (340.6 mg/kg) and lowest Cd (8.4 mg/kg) concentrations. In coal mines, Mn (284.9 mg/kg) and Cd (2.1 mg/kg) were measured highest and lowest, respectively. Pollution assessment revealed dust to be moderately polluted. Health risk assessment showed that Cr in chromite mines exhibited a mean HI value of 1.16E + 00 that was higher than the safe level (HI > 1) having the potential to cause significant health risk to workers. In coal mines, the estimated total HI was 6E-1. Sensitivity analysis revealed concentration and exposure time to be the most influential parameters contributing to risk. Therefore, governmental and nongovernmental organizations must develop dust pollution control guidelines and mitigation measures to safeguard the health of mineworkers by limiting heavy metal exposure.
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Affiliation(s)
- Zakia Sultana
- Environmental Health Laboratory, Department of Environmental Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Yasir Abdur Rehman
- Environmental Health Laboratory, Department of Environmental Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Hudda Khaleeq Khan
- Environmental Health Laboratory, Department of Environmental Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Riffat Naseem Malik
- Environmental Health Laboratory, Department of Environmental Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
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Sheng D, Meng X, Wen X, Wu J, Yu H, Wu M. Contamination characteristics, source identification, and source-specific health risks of heavy metal(loid)s in groundwater of an arid oasis region in Northwest China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 841:156733. [PMID: 35716754 DOI: 10.1016/j.scitotenv.2022.156733] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 05/28/2022] [Accepted: 06/12/2022] [Indexed: 05/09/2023]
Abstract
Heavy metal(loid)s accumulation in groundwater has posed serious ecological and health concerns worldwide. Source-specific risk apportionment is crucial to prevent and control potential heavy metal(loid)s pollution in groundwater. However, there is very limited comprehensive information on the health risk apportionment for groundwater heavy metal(loid)s in arid regions. Thus, the Zhangye Basin, a typical arid oasis region in Northwest China, was selected to investigate the contamination characteristics, possible pollution sources, and source-specific health risks of groundwater heavy metal(loid)s. The heavy metal pollution index (HPI), the Nemerow index (NI), and the contamination degree (CD) were adopted to assess the pollution level of heavy metal(loid)s; then source-specific health risk was apportioned integrating the absolute principal component scores-multiple linear regression (APCS-MLR) with health risk assessment. Noticeable accumulation of Mn, Fe, and As was observed in this region with especially Fe/As in 12.68%/2.11% of the samples revealing significant enrichment. Approximately 3.5% of the groundwater samples caused moderate or higher pollution level based on the HPI. The APCS-MLR model was more physically applicable for the current research than the positive matrix factorization (PMF) model. Industrial-agricultural activity factor (12.56%) was the major source of non-cancer (infants: 59.15%, children: 64.87%, teens: 64.06%, adults: 64.02%) and cancer risks (infants: 77.36%, children: 77.35%, teens: 77.40%, adults: 77.41%). Industrial-agricultural activities should be given priority to control health risks of heavy metal(loid)s in groundwater. These findings provide fundamental and significant information for mitigating health risks caused by heavy metal(loid)s in groundwater of typical arid oasis regions by controlling priority sources.
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Affiliation(s)
- Danrui Sheng
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, Gansu 730000, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Xianhong Meng
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, Gansu 730000, People's Republic of China
| | - Xiaohu Wen
- Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, Gansu 730000, People's Republic of China.
| | - Jun Wu
- Yantai Research Institute, Harbin Engineering University, Yantai, Shandong 264006, People's Republic of China.
| | - Haijiao Yu
- School of Resources and Environment, Linyi University, Linyi, Shandong 276005, People's Republic of China
| | - Min Wu
- College of Geomatics, Xi'an University of Science and Technology, Xi'an, Shaanxi 710054, People's Republic of China
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Rashid S, Shah IA, Supe Tulcan RX, Rashid W, Sillanpaa M. Contamination, exposure, and health risk assessment of Hg in Pakistan: A review. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 301:118995. [PMID: 35189298 DOI: 10.1016/j.envpol.2022.118995] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 02/11/2022] [Accepted: 02/12/2022] [Indexed: 06/14/2023]
Abstract
Mercury is a highly toxic and highly mobile heavy metal. It has been regarded as more toxic than other nonessential and toxic nonradioactive heavy metals. Moreover, it has a high tendency of bioaccumulation and biomagnification in the ecosystem. This study aimed to assess the environmental and health risks related to Hg. Seventy studies related to Hg in environmental media, aquatic biota, and food stuffs across Pakistan were reviewed, and their concentrations were used for ecological and human health risk assessments. High concentrations of Hg were reported in the environment, with maximum concentrations of 72 mg L-1, 144 mg kg-1, 887 mg kg-1, and 49,807 ng m-3 in surface water, surface soil, surface sediments, and urban atmosphere, respectively. The possible non-carcinogenic health risk (hazard quotient) of Hg was assessed in soil, water, and fish. High risks were calculated for seafood and vegetable consumption, while low risks were estimated for soils and groundwater ingestion and exposure. Overall, children showed higher risks than adults. Last, the risk quotient analysis (RQ) revealed significant risks for aquatic species. RQs showed that multiple species, especially those with smaller resilience, could face long-term detrimental impacts. High, medium, and low risks were calculated from 66.66, 16.17, and 16.17% of the reported Hg concentrations.
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Affiliation(s)
- Sajid Rashid
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, No. 19 Xinjiekouwai Street, Beijing, 100875, China
| | - Izaz Ali Shah
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, No. 19 Xinjiekouwai Street, Beijing, 100875, China
| | - Roberto Xavier Supe Tulcan
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing, 100875, China
| | - Wajid Rashid
- Department of Environmental and Conservation Sciences, University of Swat, 19130, Pakistan.
| | - Mika Sillanpaa
- Department of Chemical Engineering, School of Mining, Metallurgy and Chemical Engineering, University of Johannesburg, P. O. Box 17011, Doornfontein, 2028, South Africa; Chemistry Department, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia; Department of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia; International Research Centre of Nanotechnology for Himalayan Sustainability, Shoolini University, Solan, 173212, Himachal Pradesh, India
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Zohra T, Ikram A, Salman M, Amir A, Saeed A, Ashraf Z, Ahad A. Wastewater based environmental surveillance of toxigenic Vibrio cholerae in Pakistan. PLoS One 2021; 16:e0257414. [PMID: 34591885 PMCID: PMC8483414 DOI: 10.1371/journal.pone.0257414] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 09/01/2021] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Pakistan has been experiencing intervals of sporadic cases and localized outbreaks in the last two decades. No proper study has been carried out in order to find out the environmental burden of toxigenic V. cholerae as well as how temporal and environmental factors associated in driving cholera across the country. METHODS We tested waste water samples from designated national environment surveillance sites in Pakistan with RT-PCR assay. Multistage sampling technique were utilized for samples collection and for effective sample processing Bag-Mediated Filtration system, were employed. Results were analysed by district and month wise to understand the geographic distribution and identify the seasonal pattern of V. cholera detection in Pakistan. RESULTS Between May 2019, and February 2020, we obtained and screened 160 samples in 12 districts across Pakistan. Out of 16 sentinel environmental surveillance sites, 15 sites showed positive results against cholera toxigenic gene with mostly lower CT value (mean, 34±2) and have significant difference (p < 0.05). The highest number of positive samples were collected from Sindh in month of November, then in June it is circulating in different districts of Pakistan including four Provinces respectively. CONCLUSION V. cholera detection do not follow a clear seasonal pattern. However, the poor sanitation problems or temperature and rainfall may potentially influence the frequency and duration of cholera across the country. Occurrence of toxigenic V. cholerae in the environment samples showed that cholera is endemic, which is an alarming for a potential future cholera outbreaks in the country.
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Affiliation(s)
- Tanzeel Zohra
- Public Health Laboratories Division, Department of Microbiology, National Institute of Health, Islamabad, Pakistan
| | - Aamer Ikram
- Public Health Laboratories Division, Department of Microbiology, National Institute of Health, Islamabad, Pakistan
| | - Muhammad Salman
- Public Health Laboratories Division, Department of Microbiology, National Institute of Health, Islamabad, Pakistan
| | - Afreenish Amir
- Public Health Laboratories Division, Department of Microbiology, National Institute of Health, Islamabad, Pakistan
| | - Asim Saeed
- Public Health Laboratories Division, Department of Microbiology, National Institute of Health, Islamabad, Pakistan
| | - Zurva Ashraf
- Public Health Laboratories Division, Department of Microbiology, National Institute of Health, Islamabad, Pakistan
| | - Abdul Ahad
- Public Health Laboratories Division, Department of Microbiology, National Institute of Health, Islamabad, Pakistan
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Abbas Z, Imran M, Natasha N, Murtaza B, Amjad M, Shah NS, Khan ZUH, Ahmad I, Ahmad S. Distribution and health risk assessment of trace elements in ground/surface water of Kot Addu, Punjab, Pakistan: a multivariate analysis. ENVIRONMENTAL MONITORING AND ASSESSMENT 2021; 193:351. [PMID: 34021412 DOI: 10.1007/s10661-021-09150-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 05/17/2021] [Indexed: 06/12/2023]
Abstract
Water is a key component for living beings to sustain life and for socio-economic development. Anthropogenic activities contribute significantly to ground/surface water contamination particularly with trace elements. The present study was designed to evaluate distribution and health risk assessment of trace elements in ground/surface water of the previously unexplored area, Tehsil Kot Addu, Southern-Punjab, Pakistan. Ground/surface water samples (n = 120) were collected from rural and urban areas of Kot Addu. The samples were analyzed for physicochemical characteristics: total dissolved solids (TDS), pH, and EC (electrical conductivity), cations, anions, and trace elements particularly arsenic (As), lead (Pb), cadmium (Cd), and zinc (Zn). All of the water characteristics were evaluated based on the water quality standards set by World Health Organization (WHO). Results revealed the suitability of water for drinking purpose with respect to physicochemical attributes. However, the alarming levels of trace elements especially As, Cd, and Pb make it unfit for drinking purpose. Noticeably, 23, 96, and 98% of water samples showed As, Cd, and Pb concentrations higher than the permissible limits. Overall, the estimated carcinogenic and non-carcinogenic risk to the exposed community was higher than the safety level of USEPA, suggesting the probability of cancer and other diseases through long-term exposure via ingestion routes. Therefore, this study demonstrated an urgent need for water filtration/purification techniques, and some quality control measures are warranted to protect the health of the exposed community in Tehsil Kot Addu.
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Affiliation(s)
- Zafar Abbas
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan
| | - Muhammad Imran
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan.
| | - Natasha Natasha
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan
| | - Behzad Murtaza
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan.
| | - Muhammad Amjad
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan
| | - Noor Samad Shah
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan
| | - Zia Ul Haq Khan
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan
| | - Iftikhar Ahmad
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan
| | - Sajjad Ahmad
- Department of Environmental Sciences, COMSATS University Islamabad, Vehari-Campus, Vehari, 61100, Pakistan
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Sheng D, Wen X, Wu J, Wu M, Yu H, Zhang C. Comprehensive Probabilistic Health Risk Assessment for Exposure to Arsenic and Cadmium in Groundwater. ENVIRONMENTAL MANAGEMENT 2021; 67:779-792. [PMID: 33606066 DOI: 10.1007/s00267-021-01431-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 01/13/2021] [Indexed: 06/12/2023]
Abstract
Probabilistic health risk assessment has widely been used for more realistic risk analysis of contaminants. However, the existing probabilistic modeling process may be unable to reflect the actual health risks comprehensively. In the present study, the Monte Carlo simulation was employed to assess the probabilistic health risks of exposing to arsenic (As) and cadmium (Cd) in groundwater through ingestion and dermal contact pathways. To systematically evaluate the actual health risks of residents, two scenarios of the probabilistic health risk assessment were proposed: (1) fixed exposure parameters, whereas uncertain metal concentrations, and (2) uncertain exposure parameters and metal concentrations. The results indicated that the mean hazard index (HI) for local residents was mostly accepted (HI < 1), while the non-cancer risk of infants at the 95th percentile under scenario 2 (HI = 1.42) exceeded the safe level of 1, signifying the potential non-cancer risk on infants. Meanwhile, the average total cancer risk (TCR) values were several times greater than the acceptable limit of 1E-06 for all the age groups under both scenarios 1 and 2, reflecting the unacceptable cancer risk. Moreover, sensitivity analysis identified the exposure duration (ED) and concentration factor (CW) were the most relevant parameters that affect the health risk. Overall, the results of this study will be useful for the policy makers in comprehensively understanding the actual health risks of the heavy metal(loids) contamination in groundwater on receptors, as well as setting up suitable groundwater management strategies to guarantee safe water supply and to maintain health for local residents.
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Affiliation(s)
- Danrui Sheng
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, Gansu, People's Republic of China
- University of Chinese Academy of Sciences, 100049, Beijing, People's Republic of China
| | - Xiaohu Wen
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, Gansu, People's Republic of China.
| | - Jun Wu
- School of Resources and Environmental Engineering, Ludong University, Yantai, 264025, Shandong, People's Republic of China.
| | - Min Wu
- Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, Gansu, People's Republic of China
- University of Chinese Academy of Sciences, 100049, Beijing, People's Republic of China
| | - Haijiao Yu
- Faculty of Geographical Science, Beijing Normal University, 100875, Beijing, People's Republic of China
| | - Chuanqi Zhang
- Liaoning Huayi Environmental Consulting Co., Ltd, Shenyang, 110000, Liaoning, People's Republic of China
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Jamal R, Mubarak S, Sahulka SQ, Kori JA, Tajammul A, Ahmed J, Mahar RB, Olsen MS, Goel R, Weidhaas J. Informing water distribution line rehabilitation through quantitative microbial risk assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 739:140021. [PMID: 32758946 DOI: 10.1016/j.scitotenv.2020.140021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/01/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
Poor urban water quality has been linked to diminished source water quality, poorly functioning water treatment systems and infiltration into distribution lines after treatment resulting in microbiological contamination. With limited funding to rehabilitate distribution lines, developing nations need tools to identify the areas of greatest concern to human health so as to target cost effective remediation approaches. Herein, a case study of Hyderabad, Pakistan was used to demonstrate the efficacy of combining quantitative microbial risk assessment (QMRA) for multiple pathogens with spatial distribution system modeling to identify areas for pipe rehabilitation. Abundance of Escherichia coli, Enterococcus (enterococci), Salmonella spp., Shigella spp., Giardia intestinalis, Vibrio cholera, norovirus GI and adenovirus 40/41, were determined in 85 locations including the source water, treatment plant effluent and the city distribution lines. Bayesian statistics and Monte Carlo simulations were used in the QMRA to account for left-censored microbial abundance distributions. Bacterial and viral abundances in the distribution system samples decreased as follows: 9400 ± 19,800 norovirus gene copies/100 mL (average ± standard deviation, 100% of samples positive); 340 ± 2200 enterococci CFU/100 mL (94%), 71 ± 97 Shigella sp. CFU/100 mL (97%), 60 ± 360 E. coli CFU/100 mL (89%), 35 ± 79 adenovirus gene copies/100 mL (100%), and 21 ± 46 Salmonella sp. CFU/100 mL (76%). The QMRA revealed unacceptable probabilities of illness (>1 in 10,000 illness level) from the four exposure routes considered (drinking water, or only showering, tooth brushing, and rinsing vegetables consumed raw). Disease severity indices based on the QMRA combined with mapping the distribution system revealed areas for targeted rehabilitation. The combined intensive sampling, risk assessment and mapping can be used in low- and middle-income countries to target distribution system rehabilitation efforts and improve health outcomes.
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Affiliation(s)
- Rubayat Jamal
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA
| | - Shaista Mubarak
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Sierra Q Sahulka
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA
| | - Junaid A Kori
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Ayesha Tajammul
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Jamil Ahmed
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | - Rasool B Mahar
- US Pakistan Center for Advanced Studies in Water, Mehran University of Engineering and Technology, Jamshoro, 76062, Sindh, Pakistan
| | | | - Ramesh Goel
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA
| | - Jennifer Weidhaas
- Civil and Environmental Engineering, University of Utah, 110 Central Campus Drive Suite 2000, Salt Lake City, UT 84112, USA.
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