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1.
Environ Monit Assess ; 192(7): 421, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32514793

RESUMO

Due to unevenly distributed water resources, semi-arid regions are particularly prone to severe water shortage and quality degradation. In this study, based on long-term hydrological database (1935-2015), and the latest available water quality data sets (2011-2016), we analyzed the water crisis and its driving forces in the upper Yongding River watershed, a typical water shortage area in North China. The results showed that human induced excessive water consumption is responsible for the significantly decreased river flow over the past eight decades. Although the capacity of the watershed wastewater treatment has improved, current water quality does not meet the requirements of the national water management goals, because of the excessive nitrogen and CODCr (chemical oxygen demand), which mainly come from the wastewater and feedlots discharge. Due to the decreased river flow, current Yongding River is unable to dilute and assimilate pollutions. The analysis of river pollutant load illustrated that more than 60 % of the nitrogen in the river water system is diverted for reservoir storage, and more than 50 % of the CODCr and TP are diverted for irrigation, thereby, increasing the risk of reservoirs eutrophication and threatening food safety. Besides, the high Cl- (388.2 ± 322.5 mg/L) and SO42- (470.6 ± 357.7 mg/L) imply that the upper river water are not suitable for drinking and irrigation purposes, and a potential risk of salinization if the river flow continues to decrease. We conclude that water resources over extraction and quality degradation are the main driving factors of the Yongding River water crisis.


Assuntos
Monitoramento Ambiental , Rios , Poluentes Químicos da Água , Qualidade da Água , China , Humanos , Nitrogênio/análise , Movimentos da Água , Poluentes Químicos da Água/análise , Qualidade da Água/normas
2.
Ann Ig ; 32(5): 439-448, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32578839

RESUMO

Public health measures to cope with the Covid-19 pandemic, imposed also a shutdown of sports facilities and swimming pools. Safety issues related to recreational waters were emerging during the lockdown, rising concerns on how and when reopening pools and on how improve their management while SARS-CoV-2 is circulating in the population. The GSMS-SItI, Working Group on Movement Sciences for Health of the Italian Society of Hygiene Preventive Medicine and Public Health, discussed and summarized some indications for a suitable preventive approach. Several measures are highlighted, including social distancing, optimized water management, airflow and microclimatic parameters in the pool as well in the annexed rooms, verification of sanitation procedures. The GSMS-SItI underlines that prevention should be based on monitoring of the local epidemiological situation and on the constant collaboration with the local health authority and the national health service.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Controle de Infecções/métodos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Saúde Pública , Piscinas/normas , Qualidade da Água/normas , Infecções por Coronavirus/transmissão , Transmissão de Doença Infecciosa/prevenção & controle , Desinfecção , Exercício Físico , Arquitetura de Instituições de Saúde , Humanos , Higiene/normas , Itália , Equipamento de Proteção Individual , Pneumonia Viral/transmissão , Vigilância da População , Quarentena , Medição de Risco , Microbiologia da Água/normas , Purificação da Água/métodos , Purificação da Água/normas
3.
Proc Natl Acad Sci U S A ; 117(21): 11566-11572, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32385161

RESUMO

Large-scale and rapid improvement in wastewater treatment is common practice in developing countries, yet this influence on nutrient regimes in receiving waterbodies is rarely examined at broad spatial and temporal scales. Here, we present a study linking decadal nutrient monitoring data in lakes with the corresponding estimates of five major anthropogenic nutrient discharges in their surrounding watersheds over time. Within a continuous monitoring dataset covering the period 2008 to 2017, we find that due to different rates of change in TN and TP concentrations, 24 of 46 lakes, mostly located in China's populated regions, showed increasing TN/TP mass ratios; only 3 lakes showed a decrease. Quantitative relationships between in-lake nutrient concentrations (and their ratios) and anthropogenic nutrient discharges in the surrounding watersheds indicate that increase of lake TN/TP ratios is associated with the rapid improvement in municipal wastewater treatment. Due to the higher removal efficiency of TP compared with TN, TN/TP mass ratios in total municipal wastewater discharge have continued to increase from a median of 10.7 (95% confidence interval, 7.6 to 15.1) in 2008 to 17.7 (95% confidence interval, 13.2 to 27.2) in 2017. Improving municipal wastewater collection and treatment worldwide is an important target within the 17 sustainable development goals set by the United Nations. Given potential ecological impacts on biodiversity and ecosystem function of altered nutrient ratios in wastewater discharge, our results suggest that long-term strategies for domestic wastewater management should not merely focus on total reductions of nutrient discharges but also consider their stoichiometric balance.


Assuntos
Lagos/química , Nitrogênio/análise , Fósforo/análise , Águas Residuárias/química , Purificação da Água , China , Ecossistema , Monitoramento Ambiental , Purificação da Água/métodos , Purificação da Água/normas , Qualidade da Água/normas
4.
Washington; Organización Panamericana de la Salud; mayo 11, 2020. 3 p.
Não convencional em Espanhol | LILACS | ID: biblio-1096915

RESUMO

Proporcionar acceso universal a las estaciones públicas de higiene de manos, con indicaciones precisas para su uso correcto. •Garantizar el suministro continuo de agua segura en las instalaciones de salud. •Asegurar que las instalaciones de atención a largo plazo y los espacios comunitarios cerrados tengan un suministro continuo de agua segura. •Asegurar el acceso de agua segura a no más de 500 metros de la residencia. •Abogar para el acceso continuo de agua segura para toda la población. •Instalar tanques de almacenamiento temporales en áreas desatendidas y donde haya un servicio interrumpido, con niveles de cloro residual de 0,5 mg/L. •Asegurar que los tanques de agua y los camiones cisterna tengan un nivel de cloro residual de 0,5-1 mg/L. •Asegurar que el nivel de cloro residual en todo el sistema de suministro y en el punto de uso es de 0,5 mg/L. •Fortalecer las acciones de vigilancia de la calidad del agua, especialmente en las zonas más afectadas. •Promover el almacenamiento seguro de agua en los hogares, como tanques elevados con tapas y grifos. •Promover tecnologías de bajo costo para garantizar la calidad del agua, como los filtros de agua domésticos. •Realizar la coordinación del sector salud, con el sector de agua y otros sectores relevantes para definir e implementar las intervenciones. •Abogar por la participación intersectorial (por ejemplo, sector del agua, agricultura) en los comités de emergencia y desastre de los paises. •Reparar las tuberías con fugas. •Establecer una prohibición sobre el uso de mangueras. • Recomendar el uso de sistemas de inodoros de bajo flujo (por diseño o modernizados) en áreas propensas a la sequía. •Realizar intervenciones de prevención que hayan demostrado ser efectivas contra el SARS-COV-2.


This technical note contains recommendations for the public sector, the community, and health establishments to make rational use of water in conditions of low water availability due to drought.


Assuntos
Pneumonia Viral/prevenção & controle , Qualidade da Água/normas , Desinfecção das Mãos/normas , Saúde Ambiental/normas , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/epidemiologia , Pandemias/prevenção & controle , Betacoronavirus
5.
Washington; Organización Panamericana de la Salud; mayo 11, 2020. 4 p.
Não convencional em Inglês, Espanhol | LILACS | ID: biblio-1096872

RESUMO

Esta ficha contiene indicadores y estándares mínimos necesarios para la respuesta a la emergencia en los siguientes temas: cantidad de agua, acceso al agua, calidad del agua, saneamiento, higiene, residuos sólidos, limpieza y desinfección, así como dosificaciones para la preparación de soluciones desinfectantes utilizando hipoclorito de sodio.


This technical note contains indicators and minimum standards necessary for emergency response in the following topics: quantity of water, access to water, quality of water, sanitation, hygiene, solid waste, cleaning and disinfection, as well as dosages for the preparation of solutions disinfectants using sodium hypochlorite.


Assuntos
Humanos , Pneumonia Viral/prevenção & controle , Qualidade da Água/normas , Higiene , Infecções por Coronavirus/prevenção & controle , Saneamento Básico/organização & administração , Pandemias/prevenção & controle , Betacoronavirus , Serviços Públicos de Saúde/normas
6.
PLoS One ; 15(5): e0230990, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32357151

RESUMO

The goal of this study was to determine the co-occurrence between acetochlor use on crops and potentially vulnerable soils in the Permanent Interstate Committee for Drought Control in the Sahel region of Western Africa. Acetochlor, a pre-emergence herbicide, is used primarily on row crops and has the potential to reach groundwater or surface water following a rain event shortly after application. Off-field transport is often determined by soil properties; therefore, soils within potential use areas were assessed and mapped to establish areas with soils vulnerable to leaching and/or runoff. Corn and cotton production areas were used as surrogate crops for high potential use areas of acetochlor within areas identified using GlobCover land use data and the Spatial Production Allocation Model agricultural statistics data. The geospatial analysis identified approximately 462 million ha of potentially vulnerable soils in the Sahel region of which 65.7 million ha are within agricultural areas. An adjustment for corn and cotton production areas showed that 2.2 million ha or 3.3% of agricultural fields could have potential restrictions for acetochlor use. Approximately 0.159 million ha of soils or 0.24% of agricultural fields are in the presence of shallow groundwater, defined by depth < 9 m. In addition, 0.0128 million ha or 0.02% were determined to be adjacent to surface water bodies. To understand the uncertainty associated with the use of specific land cover datasets, an overlay assessment was conducted using alternative data sources. Overlap between selected land cover datasets in the Sahel region varies and ranges from 24.7% to 75.5% based on a merged 2009 GlobCover and CCI LC datasets. In comparison with the merged 2005 and 2009 GlobCover dataset, the cropland overlaps range from 38.9% to 85.0%. This demonstrates that the choice of land cover dataset can have a significant impact on a spatial assessment. Results from this assessment demonstrate that only a small fraction of vulnerable agricultural soils across the region may be a risk for contamination by acetochlor of groundwater or surface resources, based on product label recommendations. Given the availability of spatial data in a region, the methods contained herein may additionally be used in other localities to provide similar information that can be helpful for water quality management.


Assuntos
Biodegradação Ambiental , Monitoramento Ambiental/métodos , Água Subterrânea/análise , Herbicidas/análise , Poluentes do Solo/análise , Toluidinas/análise , Qualidade da Água/normas , África Ocidental , Humanos
7.
PLoS One ; 15(5): e0229701, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401786

RESUMO

Recreational water monitoring can be challenging due to the highly variable nature of pathogens and indicator concentrations, the myriad of potential biological hazards to measure for, and numerous access points, both official and unofficial, that are used for recreation. The aim of this study was to develop, deploy, and assess the effectiveness of a quantitative polymerase chain reaction (qPCR) community-based monitoring (CBM) program for the assessment of bacterial and parasitic hazards in recreational water. This study developed methodologies for performing qPCR 'in the field,' then engaged with water management and monitoring groups and tested the method in a real-world implementation study to evaluate the accuracy of CBM using qPCR both quantitatively and qualitatively. This study found high reproducibility between qPCR results performed by non-expert field users and expert laboratory results, suggesting that qPCR as a methodology could be amenable to a CBM program.


Assuntos
Bactérias/isolamento & purificação , Monitoramento Ambiental , Microbiologia da Água , Água/parasitologia , Bactérias/genética , Bactérias/patogenicidade , Humanos , Recreação , Qualidade da Água/normas
8.
Environ Monit Assess ; 192(6): 393, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32451637

RESUMO

The physico-chemical and bacteriological analyses of four rivers namely: Ajali, Obinna, Karawa and Adada in Ezeagu and Uzo-uwani Local Government Areas (LGAs) of Enugu State, South-eastern Nigeria, were carried out to evaluate their suitability for consumption. Water samples from Ajali River were taken from a point where the river receives brewery effluents and other two points that were impacted by non-point pollution sources. A total of 54 water samples were collected during the dry season, early rainy season and rainy season proper for 2 years. For each trip, nine samples were collected from three sampling points in Ajali and two each in Adada, Obinna and Karawa. The water quality index (WQI) was calculated using the arithmetic index method. Significant seasonal and spatial variations (p < 0.05) were evident for sulphate, phosphate, sodium, magnesium, pH, total alkalinity, nitrate and total dissolved solids. Mean values of WQI were 71.75 ± 16.07 57.26 ± 5.39, 60.47 ± 13.12, and 66.75 ± 15.30 for Adada, Obinna, Karawa and Ajali, respectively.


Assuntos
Agricultura , Monitoramento Ambiental , Rios , Poluentes Químicos da Água , Qualidade da Água , Agricultura/estatística & dados numéricos , Nigéria , Rios/química , Estações do Ano , Poluentes Químicos da Água/análise , Qualidade da Água/normas
9.
Environ Monit Assess ; 192(6): 394, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32458103

RESUMO

The Kali River is a significant source of surface water as well as the main tributary of River Hindon that flows through major cities of western Uttar Pradesh, India. It flows throughout the urban and industrial regions; hence, it carries various amounts of pollutant. Therefore, a study was conducted to examine spatial-temporal variations in river water quality by determining physicochemical variables and heavy metal concentrations at seventeen sampling stations (S1-S17) throughout the river stretch. Various physicochemical variables, namely pH, EC, TDS, turbidity, BOD, COD, TH, TA, Ca, Mg, Na, K, HCO3-, Cl-, SO42-, NO3-, and PO43- were higher in summer than in winter. The order of mean metal concentrations was Fe > Pb > Mn > Ni > Zn > Cu > Cr > Cd. The relationships among measured physicochemical variables and pollution index were examined. Furthermore, multivariate statistical methods were used to assess spatial-temporal variation in water quality to identify current pollution sources and validate results. Water quality index and comprehensive pollution index indicated that the Kali River was less polluted from S1 to S8. However, downstream sampling sites were polluted. Pollution starts from S9 and drastically increases at and beyond S13 because of effluents from industries and sugar mills in Muzaffarnagar. The study suggests cleaning the downstream region of river to restore human health and flora and fauna in the river ecosystem.


Assuntos
Monitoramento Ambiental , Análise Multivariada , Rios , Poluentes Químicos da Água , Qualidade da Água , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Índia , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , Qualidade da Água/normas
10.
Environ Monit Assess ; 192(4): 261, 2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242256

RESUMO

River water quality monitoring at limited temporal resolution can lead to imprecise and inaccurate classification of physicochemical status due to sampling error. Bayesian inference allows for the quantification of this uncertainty, which can assist decision-making. However, implicit assumptions of Bayesian methods can cause further uncertainty in the uncertainty quantification, so-called second-order uncertainty. In this study, and for the first time, we rigorously assessed this second-order uncertainty for inference of common water quality statistics (mean and 95th percentile) based on sub-sampling high-frequency (hourly) total reactive phosphorus (TRP) concentration data from three watersheds. The statistics were inferred with the low-resolution sub-samples using the Bayesian lognormal distribution and bootstrap, frequentist t test, and face-value approach and were compared with those of the high-frequency data as benchmarks. The t test exhibited a high risk of bias in estimating the water quality statistics of interest and corresponding physicochemical status (up to 99% of sub-samples). The Bayesian lognormal model provided a good fit to the high-frequency TRP concentration data and the least biased classification of physicochemical status (< 5% of sub-samples). Our results suggest wide applicability of Bayesian inference for water quality status classification, a new approach for regulatory practice that provides uncertainty information about water quality monitoring and regulatory classification with reduced bias compared to frequentist approaches. Furthermore, the study elucidates sizeable second-order uncertainty due to the choice of statistical model, which could be quantified based on the high-frequency data.


Assuntos
Benchmarking , Qualidade da Água/normas , Teorema de Bayes , Monitoramento Ambiental/métodos , Incerteza , Água
11.
Environ Monit Assess ; 192(5): 308, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32328812

RESUMO

The continuous deterioration of drinking water quality supplies by several anthropogenic activities is a serious global challenge in recent times. In this current study, the drinking water quality of Ikem rural agricultural area (southeastern Nigeria) was assessed using chemometrics and multiple indexical methods. Twenty-five groundwater samples were collected from hand-dug wells and analyzed for physicochemical parameters such as pH, major ions, and heavy metals. The pH of the samples (which ranged between 5.2 and 6.7) indicated that waters were slightly acidic. Cations and anions (except for phosphate) were within their respective standard limits. Except for Mn, heavy metals were also found to be below their maximum allowable limits. Factor analysis identified both geogenic processes and anthropogenic inputs as possible origins of the analyzed physicochemical parameters. Modified heavy metal index, geoaccumulation index, and overall index of pollution revealed that all the hand-dug wells were in excellent condition, and hence safe for drinking purposes. However, pollution load index, water quality index (WQI), and entropy-weighted water quality index (EWQI) revealed that some wells (about 8-12%) were slightly contaminated, and hence are placed in good water category. A hierarchical cluster analysis (HCA) was performed based on the integration of the WQI and EWQI results. The HCA revealed two major quality categories of the samples. While the first cluster comprises of samples classified as excellent drinking water by both WQI and EWQI models, the second cluster comprises of about 12% samples which were identified as good water by either the WQI or EWQI.


Assuntos
Água Potável , Monitoramento Ambiental , Qualidade da Água , Água Potável/química , Água Potável/normas , Monitoramento Ambiental/métodos , Água Subterrânea/química , Nigéria , Poluentes Químicos da Água/análise , Qualidade da Água/normas , Abastecimento de Água/normas
12.
Environ Monit Assess ; 192(5): 312, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32328819

RESUMO

Continuous monitoring of water quality in dam reservoirs is a typically difficult and costly operation. In this study, the results of computer modeling with the CE-QUAL-W2 model were combined with data mining techniques to develop a new method called "delta-normal stress" for identifying the critical temporal and spatial monitoring ranges. For this purpose, long-term variations of three quality parameters including nitrite-nitrate level, dissolved oxygen (DO) level, and water temperature near the outlet of the dam, which is the point of interest for reservoir exploitation, were analyzed. Based on this analysis, the time intervals and depth ranges with the highest frequency of significant variations in terms of each parameter were identified. The results showed that given the difference between the delta-normal stress trend of temperature and that of other parameters in Karkheh Dam Reservoir, temperature can be monitored at much lower sampling resolutions and using cheaper methods and equipment without sacrificing accuracy. Based on the frequency of occurrence of delta-normal stress of more than 20% above the total average, the key sampling times and locations for nitrite-nitrate and DO levels were determined to be the periods of January-February, February-March, and March-April, and depths of 60, 55, 50, and 5 m, respectively.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Água/química , Poluentes Químicos da Água/análise , Qualidade da Água/normas , Abastecimento de Água
13.
Ecotoxicol Environ Saf ; 195: 110436, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32182527

RESUMO

Sediment is the most dominant reservoir of organic pollutants in the aquatic environment. Understanding carbon and nitrogen sources in sediments and factors that controls distribution enhances our understanding of biogeochemical cycles of carbon and nitrogen. Different end-members and surface sediments of rivers and sediments profiles of lakes were collected. The concentrations of TOC and TON and their δ13C and δ15N were studied for qualitative and quantitative analysis of natural and anthropogenic sources. The results show that TOC and TON concentrations of the sediments from rivers range from 0.63% to 10.83% and 0.06%-0.86%, respectively, indicating substantial great environmental risks in these rivers. The concentrations of TOC and TON for the four sediment profiles below the 5 cm, increase in the order of Miyun < Chuidiao < Qunming < Houhai, as influenced by their respective environment condition. Moreover, water quality was quite good and there was no risk of eutrophication in Miyun reservoir. δ13Corg and δ15Norg in surface sediments of the studied 18 rivers range from -27.2‰ to -24.9‰ and -2.2‰ to +10.9‰, respectively. Based on a simple δ13C-based end-member mixing and a C/N ratio model, organic matter in the surface sediments of these rivers were mainly derived from sewage and C3 plant. In addition, the sources of organic matter differed in each layer of the four sediment profiles. This study provides a reliable method for qualitative and quantitative identification of the source of organic matter in sediments, and offers theoretical basis for better management of rivers and lakes.


Assuntos
Carbono/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos/química , Nitrogênio/análise , Rios/química , Poluentes Químicos da Água/análise , Isótopos de Carbono , Eutrofização , Isótopos de Nitrogênio , Compostos Orgânicos/análise , Esgotos/análise , Qualidade da Água/normas
14.
Bull Environ Contam Toxicol ; 104(5): 575-581, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32166333

RESUMO

Intensive agricultural and livestock activities demand high pesticide use and, consequently, contaminants reach aquatic ecosystems. In the lower Jacuí River, southern Brazil, there is a lack of knowledge about pesticide residues in water samples and the biochemical responses in native fish species. Thus, this study aimed to estimate the influence of pesticide residues and water parameters to biomarker responses in the native fish Astyanax spp. We performed seasonal biomonitoring in 2017 with water samples and fish collections. Biomarkers of oxidative stress, antioxidants, biotransformation, and neurotoxicity were analyzed in fish tissues. Fourteen pesticide residues were detected; they presented correlations with detoxification enzyme and oxidative stress biomarkers. These data indicate that most of variations can be related to the pesticide presence in water indicating high aquatic pollution in this place.


Assuntos
Characidae/metabolismo , Monitoramento Ambiental/métodos , Praguicidas/análise , Rios/química , Poluentes Químicos da Água/análise , Qualidade da Água/normas , Agricultura , Animais , Biomarcadores/metabolismo , Brasil , Ecossistema , Estresse Oxidativo/efeitos dos fármacos , Praguicidas/metabolismo , Poluentes Químicos da Água/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-32208958

RESUMO

Benthic macroinvertebrates are used to evaluate water quality in 8 sampling stations in Lepenci river basin in Kosovo. Sampling was performed in spring, summer and fall 2017. Following biotic indices are used: EPT taxa richness, Biological Monitoring Working Party (BMWP), Average Score per Taxon (ASPT), Stroud Water Research Center index (SWRC), Family biotic index (FBI), as well as diversity indices: Shannon-Weaver index (H), Simpsons index (D), Hill's index (Hi), Mergalef index (DMe) and Menhicnik's index (DMa). Our results show the presence of 34 macroinvertebrate taxa in Lepenci river which belong to Insecta, Crustaceans and Annelidae. The water quality along the river show variation from high and good class upstream, to moderate, poor and bad, downstream. The Pearson's bivariate correlation used to analyze the relationship between physicochemical parameters with biotic and diversity indices showed a significant correlation (p < 0.01) of EC, TSS, O2, COD, BOD, NH4, and PO43- with biotic indices EPT, BMWP, ASPT, SWRC, FBI. We can conclude that the values of biotic and diversity indices have shown differences in water quality between polluted and unpolluted sites and reflect the ecological status of the river, therefore we can consider them as valuable tools for water quality assessment in rivers in Kosovo.


Assuntos
Monitoramento Ambiental/métodos , Invertebrados/classificação , Rios/química , Poluentes Químicos da Água/análise , Qualidade da Água/normas , Animais , Ecossistema , Kosovo , Estações do Ano
16.
Chemosphere ; 251: 126379, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32171130

RESUMO

Ammonia is one of the two mandatory indexes for China's water environment pollution control. The current China ammonia water quality standard does not reflect the effect of water quality parameters on ammonia toxicity. The Ministry of Ecology and Environment of China just released the China National Aquatic Life Criteria Report for ammonia. This paper discusses the technical route, formulation process and results of the national ammonia criteria. Based on China's own technical guidelines, a total of 259 acceptable acute and 44 acceptable chronic data for ammonia were adopted. The temperature of the water body corresponding to the ammonia criteria was divided into 6 grades, and the pH was divided into 12 grades, which constitutes 72 groups of water quality conditions. Based on the empirical formulas recommended by USEPA, the ammonia toxicity data was adjusted, and the optimal fitting model was used to derive the 72 short-term criteria and the 72 long-term criteria for ammonia. In terms of criteria derivation, the method used by the USEPA to extrapolate at the criteria level has been improved and replaced with extrapolation at the species level, making the final criteria value more accurate.


Assuntos
Amônia/análise , Conservação dos Recursos Naturais , Poluentes Químicos da Água/análise , Qualidade da Água/normas , Animais , China , Ecologia , Água Doce , Estados Unidos , United States Environmental Protection Agency
17.
Bull Environ Contam Toxicol ; 104(4): 538-544, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32130459

RESUMO

The Three Gorges Dam (TGD) is the largest hydropower facility in the world, influencing the riverine hydrology and mass flux in the Yangtze River. Little is known about its impact on the riverine dissolved organic matter (DOM) quality. In this work, the water quality and DOM quality for water samples collected from the upstream and downstream sites of TGD were investigated. The presence of TGD significantly affects the quantity and quality of DOM but has no pronounced effect on nutrient concentrations. Upstream DOM had higher concentration but lower average molecular weight and aromaticity than the downstream DOM. The biological processes in the dam reservoir contribute significantly to upstream DOM. In the downstream sites, terrestrial DOM input raises the average molecular weight and aromaticity of the overall DOM pool. These results suggest that TGD will influence not only the mass flux of organic carbon but also its quality and lability, which has both environmental and ecological significance.


Assuntos
Monitoramento Ambiental/métodos , Substâncias Húmicas/análise , Rios/química , Qualidade da Água/normas , China , Centrais Elétricas
18.
PLoS One ; 15(3): e0227611, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32196493

RESUMO

This paper presents country-level estimates of water, sanitation and hygiene (WASH)-related mortality and the economic losses associated with poor access to water and sanitation infrastructure in sub-Saharan Africa (SSA) from 1990 to 2050. We examine the extent to which the changes that accompany economic growth will "solve" water and sanitation problems in SSA and, if so, how long it will take. Our simulations suggest that WASH-related mortality will continue to differ markedly across countries in sub-Saharan Africa. In many countries, expected economic growth alone will not be sufficient to eliminate WASH-related mortality or eliminate the economic losses associated with poor access to water and sanitation infrastructure by 2050. In other countries, WASH-related mortality will sharply decline, although the economic losses associated with the time spent collecting water are forecast to persist. Overall, our findings suggest that in a subset of countries in sub-Saharan Africa (e.g., Angola, Niger, Sierra Leone, Chad and several others), WASH-related investments will remain a priority for decades and require a long-term, sustained effort from both the international community and national governments.


Assuntos
Desenvolvimento Econômico/tendências , Higiene/normas , Mortalidade/tendências , Saneamento/normas , Qualidade da Água/normas , África ao Sul do Saara/epidemiologia , Previsões , Humanos , Higiene/economia , Saneamento/economia , Desenvolvimento Sustentável/economia , Desenvolvimento Sustentável/tendências , Abastecimento de Água/economia , Abastecimento de Água/normas
20.
PLoS One ; 15(2): e0229303, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32074128

RESUMO

INTRODUCTION: Diarrhea is one of the leading causes of child morbidity and mortality in low- and middle-income countries like Ethiopia. The use of safe drinking water and improved sanitation are important practices to prevent diarrhea. However, limited research has been done to link water supply, sanitation and hygiene practices and childhood diarrhea. Therefore, this study aimed at assessing the association between microbial quality of drinking water, sanitation and hygiene practices and childhood diarrhea. METHODS: Community-based matched case-control study design was applied on 198 paired children from June to July 2019 in Kersa and Omo Nada districts of Jimma Zone, Ethiopia. Cases are children < 5 years of age with diarrhea during the two weeks before the survey. The controls are children without diarrhea during the two weeks before the survey. Twenty-five percent matched pair samples of water were taken from households of cases and controls. Data were collected using structured questionnaire by interviewing mothers/caregivers. A sample of water was collected in nonreactive borosilicate glass bottles and analyzed by the membrane filtration method to count fecal indicator bacteria. A conditional logistic regression model was used; variables with p-value less than 0.05 were considered as significantly associated with childhood diarrhea. RESULTS: A total of 396 (each case matched with control) under-five children with their mothers/caregivers were included in this study. In the analysis, variables like presence of under-five child in their home (AOR = 2.76; 95% CI: 1.33-5.71), wealth status (AOR = 5.39; 95% CI: 1.99-14.55), main sources of drinking water (AOR = 4.01; 95% CI: 1.40-11.44), hand washing practice before water collection (AOR = 4.28; 95% CI: 1.46-12.56), treating water at household level (AOR = 1.22; 95% CI: 0.48-3.09), latrine use all the times of the day and night (AOR = 0.22; 95% CI: 0.06-0.78), using pit as method of waste disposal (AOR = 4.91; 95% CI: 1.39-13.29) and use of soap for hand washing (AOR = 2.89; 95% CI: 1.35-6.15) were significantly associated with childhood diarrhea. Moreover, 30% of sampled water from cases and 26% of sampled water from controls families were free from Escherichia coli whereas all sampled water analyzed for Total coliforms were positive. CONCLUSIONS: We conclude that the main sources of drinking water, hand washing before water drawing from a storage container, domestic waste disposal place and use of soap for hand washing were the most important factors for the prevention of childhood diarrhea.


Assuntos
Diarreia/epidemiologia , Diarreia/prevenção & controle , Higiene/normas , Saneamento/métodos , Qualidade da Água/normas , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Diarreia/microbiologia , Etiópia/epidemiologia , Feminino , Humanos , Lactente , Masculino , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Adulto Jovem
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