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1.
Water Res ; 260: 121913, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38901309

RESUMO

As global temperatures rise with climate change, the negative effects of heat on drinking water distribution systems (DWDS) are of increasing concern. High DWDS temperatures are associated with degradation of water quality through physical, chemical and microbial mechanisms. Perhaps the most pressing concern is proliferation of thermotolerant opportunistic pathogens (OPs) like Legionella pneumophila and Naegleria Fowleri. Many OPs can be controlled in DWDS by residual disinfectants such as chlorine or chloramine, but maintaining protective residuals can be challenging at high temperatures. This critical review evaluates the literature on DWDS temperature, residual disinfectant decay, and OP survival and growth with respect to high temperatures. The findings are synthesized to determine the state of knowledge and future research priorities regarding OP proliferation and control at high DWDS temperatures. Temperatures above 40 °C were reported from multiple DWDS, with a maximum of 52 °C. Substantial diurnal temperature swings from ∼30-50 °C occurred in one DWDS. Many OPs can survive or even replicate at these temperatures. However, most studies focused on just a few OP species, and substantial knowledge gaps remain regarding persistence, infectivity, and shifts in microbial community structure at high temperatures relative to lower water temperatures. Chlorine decay rates substantially increase with temperature in some waters but not in others, for reasons that are not well understood. Decay rates within real DWDS are difficult to accurately characterize, presenting practical limitations for application of temperature-dependent decay models at full scale. Chloramine decay is slower than chlorine except in the presence of nitrifiers, which are especially known to grow in DWDS in warmer seasons and climates, though the high temperature range for nitrification is unknown. Lack of knowledge about DWDS nitrifier communities may hinder development of solutions. Fundamental knowledge gaps remain which prevent understanding even the occurrence of high temperatures in DWDS, much less the overall effect on exposure risk. Potential solutions to minimize DWDS temperatures or mitigate the impacts of heat were identified, many which could be aided by proven models for predicting DWDS temperature. Industry leadership and collaboration is needed to generate practical knowledge for protecting DWDS water quality as temperatures rise.


Assuntos
Desinfecção , Água Potável , Temperatura Alta , Purificação da Água , Água Potável/microbiologia , Desinfecção/métodos , Abastecimento de Água , Microbiologia da Água , Desinfetantes/farmacologia , Qualidade da Água , Cloraminas/farmacologia , Naegleria fowleri , Legionella pneumophila
2.
Heliyon ; 10(8): e29152, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38644828

RESUMO

Access to safe, reliable, and equitable water services in urban settings of low- and middle-income countries remains a critical challenge toward achieving Sustainable Development Goal 6.1, but progress has either slowed or stagnated in recent years. A pilot water kiosk network funded by the United States Millennium Challenge Corporation was implemented by the Sierra Leone Millennium Challenge Coordinating Unit into the intermittent piped water distribution network of Freetown, Sierra Leone, as a private-public partnership to improve water service provision for households without reliable piped water connections and to reduce non-revenue water. This study employs the use of high-frequency instrumentation to monitor, model, and assess the functionality of this water kiosk network over 2,947 kiosk-days. Functionality was defined via functionality levels on a daily basis through monitored stored water levels and modeled water withdrawals. The functionality levels across the kiosk network were found to be 34% operational, 30% offline, and 35% empty. Statistically significant (p<0.001) determinants of functionality were found for several predictors across the defined thresholds. Finally, modeling of water supply, water demand and withdrawal capacity, and water storage was conducted to further explain findings and provide additionally externally relevant support for kiosk operations.

3.
Water Res ; 251: 121123, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241806

RESUMO

Computational fluid dynamics (CFD) can be a powerful tool for higher-fidelity water infrastructure planning and design. Despite decades of development and demonstration over a wide range of water systems such as clarification basins, activated sludge processes, ozone contactors, etc., CFD remains primarily used in academic research, with limited application in civil and environmental engineering practice. This limitation is contributed by its higher computational cost and demand for specialized user skills. This, however, need not be the case, if a robust and efficient surrogate model can be developed from CFD simulations and independently deployed for engineering purposes. Leveraging the emerging scientific machine learning (ML) techniques of physics-informed ML and operator learning, this study develops a composite neural network (CPNN) for learning the flow hydrodynamics and particulate matter (PM) transport and fate in clarification systems. The CPNN consists of a deep operator network (DeepONet) as an encoder and a physics-informed neural network (PINN) as a decoder. In contrast to common "black box" and lumped ML approaches, the developed CPNN directly incorporates physics principles into its architecture. Furthermore, the CPNN is designed for process-resolved and operator learning, enabling it to predict spatial hydrodynamics and PM concentration distribution (i.e., contours) across different basin geometrics and loading conditions. Compared to CFD simulation, the developed CPNN model has significantly higher computational efficiency (∼ milliseconds) while demonstrating robust predictive capability. For predicting basin hydrodynamics across 10,000 test cases, the trained CPNN model achieves an R2 above 0.8 for 66.4% of cases and an R2 above 0.4 for 89.2% of cases. A similar performance is also demonstrated by the CPNN in predicting basin PM concentration. Further investigation reveals that basin geometrics that trigger bi-modal flow solutions can be particularly challenging for ML. Additionally, this study visualizes the dependency of basin hydrodynamics and PM concentration on basin geometrics and loading conditions, providing valuable insights for optimizing basin configuration. Lastly, the potentials and benefits of web-based applications, e.g., DeepXtorm, as a user-friendly interface for the developed CPNN model is discussed. This study represents the initial step toward achieving real-time higher-fidelity water infrastructure planning, design, optimization, and regulation.


Assuntos
Hidrodinâmica , Material Particulado , Simulação por Computador , Redes Neurais de Computação
4.
J Expo Sci Environ Epidemiol ; 34(1): 3-22, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37739995

RESUMO

BACKGROUND: Advances in drinking water infrastructure and treatment throughout the 20th and early 21st century dramatically improved water reliability and quality in the United States (US) and other parts of the world. However, numerous chemical contaminants from a range of anthropogenic and natural sources continue to pose chronic health concerns, even in countries with established drinking water regulations, such as the US. OBJECTIVE/METHODS: In this review, we summarize exposure risk profiles and health effects for seven legacy and emerging drinking water contaminants or contaminant groups: arsenic, disinfection by-products, fracking-related substances, lead, nitrate, per- and polyfluorinated alkyl substances (PFAS) and uranium. We begin with an overview of US public water systems, and US and global drinking water regulation. We end with a summary of cross-cutting challenges that burden US drinking water systems: aging and deteriorated water infrastructure, vulnerabilities for children in school and childcare facilities, climate change, disparities in access to safe and reliable drinking water, uneven enforcement of drinking water standards, inadequate health assessments, large numbers of chemicals within a class, a preponderance of small water systems, and issues facing US Indigenous communities. RESULTS: Research and data on US drinking water contamination show that exposure profiles, health risks, and water quality reliability issues vary widely across populations, geographically and by contaminant. Factors include water source, local and regional features, aging water infrastructure, industrial or commercial activities, and social determinants. Understanding the risk profiles of different drinking water contaminants is necessary for anticipating local and general problems, ascertaining the state of drinking water resources, and developing mitigation strategies. IMPACT STATEMENT: Drinking water contamination is widespread, even in the US. Exposure risk profiles vary by contaminant. Understanding the risk profiles of different drinking water contaminants is necessary for anticipating local and general public health problems, ascertaining the state of drinking water resources, and developing mitigation strategies.


Assuntos
Arsênio , Água Potável , Criança , Humanos , Qualidade da Água , Reprodutibilidade dos Testes , Envelhecimento
5.
J Appalach Health ; 5(2): 32-49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38022490

RESUMO

Introduction: Quantitative studies on drinking water perceptions in Appalachia are limited. High-profile water infrastructure failures in the U.S. and Eastern Kentucky, coupled with human-made and natural disasters in the Appalachian Region, have likely impacted opinions regarding tap water. Purpose: To use existing unexplored data to describe baseline tap water v. bottled water consumption in Kentucky. Methods: Telephone-based cross-sectional data were obtained from the 2013 Kentucky Health Issues Poll (KHIP) directed by the Foundation for a Healthy Kentucky. Among many items in KHIP, self-reported consumption of bottled water over tap water, reasons for bottled water use, and demographic data were obtained. Results: Among Appalachian (n=356) and non-Appalachian (n=1,125) Kentucky respondents, a significantly higher frequency of Appalachian Kentuckians reported drinking bottled water more often than tap water relative to non-Appalachian Kentuckians (57% v. 34%; X2 p < 0.001). Appalachian residency significantly predicted bottled water consumption in simple and multivariable logistic regression adjusted for significant covariates (i.e., age, sex, and race). Among persons consuming bottled water more than tap water, Appalachian Kentuckians reported significantly more concerns regarding tap water taste or smell (p = 0.005) and safety (p = 0.008) than non-Appalachians. Implications: These results from 2013 data pre-date headline news items related to public water and likely underestimate current bottled water preferences. New data are needed, and these results warrant further investigation into tap water aesthetics in Appalachia, bottled water consumption impacts on personal finances, and approaches to build public trust for public drinking water among multiple populations including Appalachian Kentuckians.

6.
ACS ES T Water ; 3(8): 2247-2254, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37841341

RESUMO

Benzene contamination in drinking water systems affected by wildfires is a problem of emerging concern. Polyethylene pipes used in service lines and premise plumbing are vulnerable to permeation by benzene and can potentially cause challenges in sampling and remediation of contaminated systems. However, the kinetics and equilibria of the uptake of benzene by and release of benzene from pipes of differing polyethylene types and manufacturers are not well studied, leading to additional uncertainty when interpreting sampling data and selecting remediation options. This work addresses this data gap by providing diffusion and partitioning data for benzene and several varieties of polyethylene pipes, including field samples from water distribution systems. All polyethylene pipes that were studied exhibited similar partitioning behavior during benzene uptake and release, but some differences in kinetics were observed among pipes. However, these differences were of minor practical importance in the pipe contamination scenario examined in this work. The results of this study can be used in conjunction with diffusion modeling to inform remediation decisions for benzene-contaminated, polyethylene service lines, and premise plumbing.

7.
Sci Total Environ ; 893: 164775, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37308015

RESUMO

River regulation has a key role in water resource management, but the introduced pollutants cannot be underestimated. This study reported spatiotemporal variations of perfluoroalkyl acids (PFAAs) significantly affected by river regulations in a standard example of urban river network with bidirectional flow in China. Perfluoroalkyl sulfonic acids (PFSAs), mostly of domestic origin, dominated during discharge, and perfluoroalkyl carboxylic acids (PFCAs), industrial pollutants, during diversion. The estimated PFAA flux into the Yangtze River during discharge was 1.22 × 102 kg with 62.5 % from Taihu Lake and 37.5 % from the river network. And that from the Yangtze River during diversion was 90.2 kg with 72.2 % into Taihu Lake and 27.8 % into the river network. Our findings show that PFAAs can exert pressure on regional water security that most of the urban river network was at medium risk. This study improves understandings of the role of river regulations in urban water networks and provides solid reference for risk assessment.

8.
Water Res ; 239: 120058, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182309

RESUMO

Benefit cost analysis (BCA) is frequently used to evaluate potable water infrastructure (PWI) investments. However, a limitation raised by BCA researchers is the narrow view of analysts in identifying investment impacts. In this paper, we propose a systems-thinking framework, supported by data from the literature, interviews, and macroeconomic data, to provide analysts with a more systematic and comprehensive view of investment impacts. The framework, once built, can be applied to any PWI investment question, to identify the prominent impacts that an analyst should consider taking forward through the quantification stages of the BCA process. We validate our method for identifying impacts using data from New Zealand. Our method identifies impacts that are typically not valued in BCA of PWI investments, but that are a common impact of many types of PWI investment decision. Household costs, for example, score in the Top 10 investment outcomes, but are only typically valued in ex post analyses of outbreaks. These impacts warrant attention in future benefit cost analyses. An additional contribution is the development a new betweenness importance rating, which we call flow betweenness, to evaluate each impact's prominence within the PWI socio-economic system.


Assuntos
Água Potável , Análise Custo-Benefício , Investimentos em Saúde , Abastecimento de Água , Nova Zelândia
9.
Environ Sci Technol ; 57(15): 6205-6215, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37011143

RESUMO

As climate change and rapid urbanization stress our aging water infrastructure, cities are under increasing pressure to develop more flexible, resilient, and modular water management systems. In response, onsite water reuse practices have been adopted by several cities globally. In addition to technological innovation, these novel water treatment systems also require new stakeholder collaborations, relationships, and processes to support them. There are, however, few models for stakeholder arrangements that support and encourage the adoption and success of such infrastructure. In this paper, we use interviews with stakeholders involved in onsite water reuse projects in the San Francisco Bay Area to create a social network map that describes the interactions between stakeholders at large and during specific phases of project implementation. Using qualitative content analysis of expert interviews and social network analysis, we identify four actor roles that are key to the functioning of this novel water infrastructure paradigm─specialists, continuity providers, program champions, and conveners─and discuss the importance of each role through the course of project implementation. These findings can be helpful for policy interventions and outreach efforts by other cities and communities looking to implement onsite water systems.


Assuntos
Purificação da Água , São Francisco , Cidades , Urbanização , Mudança Climática
10.
Environ Manage ; 71(2): 421-431, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36370177

RESUMO

The Western United States is experiencing historic drought, increasing pressure on water management systems. Agricultural production that relies on surface water flows is therefore imperiled, requiring new innovations and partnerships in order to adapt and survive. In Arizona, some agriculture continues to rely on historic, low-tech irrigation infrastructure such as hand-dug open ditches that divert river water to flood fields. These ditch systems are managed through both formal ditch companies and informal associations. To address changing water availability and needs, ditch users regularly "tinker" with water infrastructure, experimenting and making changes beyond the original infrastructure plans. Such changes are informed and driven by local social relationships and realities of the physical infrastructure. These dynamics are critical to understanding the adaptive capacity and flexibility of the water system; however, they are challenging to recognize and record. In this paper, we apply the emerging conceptualization of sociotechnical tinkering to examine the adaptive management of irrigation ditches in the Verde Valley of Arizona. We find evidence that water users frequently tinker with their water delivery and monitoring infrastructure to respond to and anticipate changes in water availability. Viewed through the lens of sociotechnical tinkering, these interactions are understood as the material manifestations of situated practice and actor agency within a water management system. This case study contributes to literature on adaptive environmental management and the hydrosocial cycle.


Assuntos
Meio Ambiente , Água , Água/química , Agricultura , Abastecimento de Água
11.
Environ Manage ; 71(4): 730-740, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36378320

RESUMO

Hurricane Harvey caused unprecedented floods across large regions of Southeast Texas resulting in several infrastructural issues. One of the notable failures was of a drinking water source pump in Beaumont, Texas, that necessitated the emergency use of a temporary pump intake station in the Neches River system. This study examines the environmental consequences of Harvey-induced flooding in the Neches River system by focusing on sensitive locations, including a Superfund site (International Creosoting, IC) and adjacent to the temporary pump intake. Post-Harvey water samples showed greater than two orders of magnitude increase in polycyclic aromatic hydrocarbons (PAH) about 3 weeks after Harvey (350-420 µg L-1 on September 22) at locations adjacent to IC and the temporary water pump intake, which by that time was no longer in use. The organic carbon normalized PAH measurements in the heavily contaminated water samples from both locations (~3% w/w) agreed well with surficial soil/sediment samples collected at the east bank adjacent to the IC site (0.7-5.2% w/w). Furthermore, molecular diagnostic ratios of select PAHs supported the contribution of PAHs from the IC site into the surface waters. PAH measurements were consistent with sediment resuspension by floodwaters that were initially diluted by large flows but became more significant as the flood subsided. Overall, our data showed that flooding can cause high levels of contamination weeks after the initial flooding event, with potential for cascading risks through mobilization of pollutants from source areas and impacts to critical water infrastructure systems.


Assuntos
Tempestades Ciclônicas , Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Texas , Rios , Poluentes Ambientais/análise , Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Monitoramento Ambiental , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise
12.
Water Res ; 229: 119442, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36473410

RESUMO

Inter-basin water transfer (IBWT) infrastructure has been expanding to deliver water across China to meet water demands in populated and industrial areas. Water scarcity may threaten the ability to produce and distribute goods through supply chains. Yet, it is not clear if IBWTs transmit or buffer water scarcity throughout supply chains. Here we combine a national database of IBWT projects and multi-region input-output analysis to trace water transferred by IBWT and virtual scarce water (scarcity weighted water use) from IBWT sourcing basins to production sites then to end consumers. The results indicate that production and final consumption of sectoral products have been increasingly supported by IBWT infrastructure, with physically transferred water volumes doubling between 2007 and 2017. Virtual scarce water is about half of the virtual water supporting the supply chain of the nation. IBWT effectively reduced virtual scarce water supporting the supply chains of most provinces, with the exposure to water scarcity reduced by a maximum of 56.7% and 15.0% for production and final consumption, respectively. IBWT Infrastructure development can thus buffer water scarcity risk to the supply chain and should be considered in water management and sustainable development policy decisions.


Assuntos
Abastecimento de Água , Água , Insegurança Hídrica , Recursos Hídricos , China
13.
Proc Natl Acad Sci U S A ; 119(47): e2214291119, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36375068

RESUMO

Providing affordable and nutritious food to a growing and increasingly affluent global population requires multifaceted approaches to target supply and demand aspects. On the supply side, expanding irrigation is key to increase future food production, yet associated needs for storing water and implications of providing that water storage, remain unknown. Here, we quantify biophysical potentials for storage-fed sustainable irrigation-irrigation that neither depletes freshwater resources nor expands croplands but requires water to be stored before use-and study implications for food security and infrastructure. We find that water storage is crucial for future food systems because 460 km3/yr of sustainable blue water, enough to grow food for 1.15 billion people, can only be used for irrigation after storage. Even if all identified future dams were to contribute water to irrigation, water stored in dammed reservoirs could only supply 209 ± 50 km3/yr to irrigation and grow food for 631 ± 145 million people. In the face of this gap and the major socioecologic externalities from future dams, our results highlight limits of gray infrastructure for future irrigation and urge to increase irrigation efficiency, change to less water-intensive cropping systems, and deploy alternative storage solutions at scale.


Assuntos
Agricultura , Abastecimento de Água , Humanos , Água , Água Doce , Abastecimento de Alimentos , Conservação dos Recursos Naturais , Irrigação Agrícola
14.
Geohealth ; 6(11): e2022GH000605, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36381499

RESUMO

Climate change may alter access to safe drinking water, with important implications for health. We assessed the relationship between temperature and rainfall and utilization of basic drinking water (BDW) in The Gambia, Mozambique, Pakistan, and Kenya. The outcomes of interest were (a) whether the reported drinking water source used in the past 2 weeks met the World Health Organization definition of BDW and (b) use of a BDW source that was always available. Temperature and precipitation data were compiled from weather stations and satellite data and summarized to account for long- and short-term weather patterns and lags. We utilized random forests and logistic regression to identify key weather variables that predicted outcomes by site and the association between important weather variables and BDW use. Higher temperatures were associated with decreased BDW use at three of four sites and decreased use of BDW that is always available at all four sites. Increasing rainfall, both in the long- and short-term, was associated with increased BDW use in three sites. We found evidence for interactions between household wealth and weather variables at two sites, suggesting lower wealth populations may be more sensitive to weather-driven changes in water access. Changes in temperature and precipitation can alter safe water use in low-resource settings-investigating drivers for these relationships can inform efforts to build climate resilience.

15.
Environ Sci Pollut Res Int ; 29(56): 84049-84055, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36229735

RESUMO

Water is an important resource, and it is a worldwide struggle to provide water of good quality to the whole population. Despite good governing laws and guidelines set in place to help protect the water resources and ensure it is of good quality for various consumers, the water quality in South Africa is worsening due to lack of management. The deteriorating infrastructure is becoming progressively worse, due to corruption and insufficient funds. The ever-increasing number of toxicants, as well as the identification of emerging chemicals of concern, are also challenges South Africa is facing. Chemical analysis cannot determine the total biological effect of a mixture of chemical compounds, but this shortcoming can be addressed by adding effect-based methods (EBMs) to water quality monitoring programmes. In this paper, the current status of water quality monitoring in South Africa is discussed, as well as the capacity of the country to add EBMs to its water quality monitoring programmes to protect and improve human and animal life. Created in Biorender.com.


Assuntos
Países em Desenvolvimento , Qualidade da Água , Animais , Humanos , África do Sul , Recursos Hídricos , Substâncias Perigosas , Monitoramento Ambiental/métodos
16.
J Environ Manage ; 322: 116103, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36067663

RESUMO

There is a growing consensus that recycled water, as an alternative and renewable water source, can serve as a vital water supply to alleviate water scarcity problem and in support of water resilience. Accordingly, recycled water infrastructure investment has seen a significant growth in recent years in many regions of the world. However, previous studies found the perceptions of public, the main end user, toward using recycled water for potable or non-potable purposes remain negatively stereotyped. The negative stereotypes led to public rejections to the construction and operation of recycled water infrastructure. Traditionally, public perceptions of recycled water uses are captured through self-reporting interview or survey techniques. To gain a more accurate measurement of the implicit public stereotypes toward recycled water uses, this study employed an event-related potential (ERPs) technique to collect neurophysiological responses with participants and presented a few research findings. Firstly, the negative stereotypes of recycled water still exist. Secondly, the degree of human contact impacts the negative stereotypes of participants toward recycled water uses more significantly on the supply side (referring to the whole supply chain of recycled water) rather than on the demand side (referring to the potential consumers of recycled water) Third, knowledge level significantly impacts the negative stereotypes of participants toward recycled water uses that have close human contact, at both supply and demand sides, and shows a more significant impact on the supply side. The findings of study contributed to the literature through creatively dividing the negative stereotypes of recycled water into the "supply-side" and the "demand-side" ones, and meanwhile have managerial implication for policymaking and scheme implementation in the area.


Assuntos
Conservação dos Recursos Naturais , Água , China , Conservação dos Recursos Naturais/métodos , Potenciais Evocados , Humanos , Abastecimento de Água
17.
Sustain Water Resour Manag ; 8(4): 114, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35855975

RESUMO

The twenty-first century is witnessing an explosion in global population, environmental changes, agricultural land disintegration, hunger, and geopolitical instabilities. It is difficult to manage these conditions or standardize improvement systems without thinking of the three main elements or subsystems that are necessary for any meaningful development-namely water (W), energy (E), and food (F). These key elements form what is globally agreed upon as the "WEF Nexus." While considering them, one should think about the other key factors that influence WEF Nexus, including population's growth, impacts of environmental changes (including climate change), moderation and adaptation regimes to climate change and climate resilience, loss of biodiversity, and sustainable nature. Together, the WEF Nexus subsystems represent a framework to ensure environmental protection that should be seen as an ethical and socioeconomic obligation. Issues, such as protection of water resources, and strategies and management tools or mechanisms for the use of water assets and agricultural innovations under the obligations of sustainable use, are investigated in this paper. Attention is paid to the relationship between water and food (WF Nexus) or water for food security in various world regions, including the Gulf Cooperation Council (GCC) countries, Central Asia countries and the Caucasus, China, Africa, and Canada. This paper also presents analyses of a great number of up-to-date publications regarding the "Nexus" perspective and its applications and limitations. This paper suggests that the Nexus' approach, in its different concepts (WEF, WE, WF and EF), can promote sustainable development and improve the quality of life of communities, while preserving natural, human, and social capital, addressing sustainability challenges, and protecting natural resources and the environment for long-term use.

18.
ACS ES T Water ; 2(2): 357-366, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35647583

RESUMO

Wildfires have destroyed multiple residential communities in California in recent years. After fires in 2017 and 2018, high concentrations of benzene and other volatile organic compounds (VOCs) were found in public drinking water systems in fire-affected areas. The sources of the contamination and appropriate remediation have been urgent matters for investigation. This study characterizes target and non-target VOCs and semi volatile organic compounds (SVOCs) in water from a highly contaminated service line after the 2018 Camp Fire (Paradise, CA). Ninety-five organic compounds were identified or tentatively identified in the service line. Laboratory combustion experiments with drinking water pipes made of polyvinyl chloride (PVC), cross-linked polyethylene (PEX) and high-density polyethylene (HDPE) and a review of the literature were used to evaluate potential sources of the detected chemicals. Among the service line contaminants were thirty-two compounds associated with PVC pyrolysis and twenty-eight organic compounds also associated with the pyrolysis of polyethylene. The service line sample also contained fifty-five compounds associated with uncontrolled burning of biomass and waste materials. The findings support hypotheses that wildfires can contaminate drinking water systems both by thermal damage to plastic pipes and intrusion of smoke. Residual chlorine disinfectant in the water system modifies the contaminant distribution observed.

19.
Health Econ ; 31(7): 1317-1338, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35388563

RESUMO

I study the effect of rainfall shocks on child mortality at a sub-national level for a global set of developing countries. I establish that negative (positive) shocks to rainfall lead to an increase (drop) in child deaths overall. Low-income countries (LICs) and the group of countries reliant on agriculture are affected the most due to negative rainfall shocks. In LICs, the impact of negative rainfall shocks is mitigated by around 60% in districts located downstream to dams, an effect predominant among less affluent districts; in addition, the effect of rainfall fluctuations is persistent, lasting for up to three years following the shock. Results remain robust to the inclusion of relevant controls, to the consideration of relevant issues such as selective fertility and migration, and various other robustness tests.


Assuntos
Mortalidade da Criança , Água , Agricultura , Criança , Humanos , Mortalidade , Pobreza , Abastecimento de Água
20.
Cureus ; 14(1): e21477, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35223257

RESUMO

OBJECTIVE: To assess if hepatic abscess incidence in a Midwest cohort was higher in rural areas compared to metropolitan areas in relation to water infrastructure. MATERIALS AND METHODS: All cases of hepatic abscesses from Jan 1, 2016 through Dec 31, 2019 at Avera McKennan Hospital in Sioux Falls, South Dakota (SD), were retrospectively collected. Chart review was completed for each case for risk factor analysis. Microbiology cultures and patient demographic data were collected including age, gender, hometown, and ethnicity. Risk factors assessed included a history of abdominal surgery, gallbladder disease, sepsis, diverticulitis, cancer, and diabetes. The incidence of hepatic abscesses was calculated using the Poisson rate test and confidence interval equation. Averages of each risk factor were calculated. Finally, hometown was utilized to create a heatmap of disease burden and compared to the density of private wells. RESULTS: Our data yielded 116 confirmed adult hepatic abscesses between 2016 and 2019. The corrected incidence per 100,000 hospitalized patients per year is 95.66. The Poisson exact probability P-value was <0.01. Rural areas had a higher per capita incidence of abscesses and higher density of private wells. CONCLUSIONS: The incidence of hepatic abscesses is higher than national averages in this single-center study of Avera McKennan Hospital. Demographics, especially geographic location, play an important role in abscess rates. Rural location may be affecting the incidence of hepatic abscesses, explaining the much higher than expected incidence in this study. Infrastructure could be a contributing factor as much of the rural area is reliant on untreated groundwater.

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