scholarly journals Isotopic and hydrogeochemical characterization of groundwater and surface water from a mine site in Tanzania

2021 ◽  
Author(s):  
Musiba Masamba Musiba ◽  
Mwemezi J. Rwiza
Keyword(s):  
Anthropogenic Activities ◽  
World Health ◽  
Elevated Concentration ◽  
Piper Diagram ◽  
Ph Values ◽  
Isotopic Studies ◽  
Western Side ◽  
Hydrogeochemical Characterization ◽  
Health Organization

Abstract This study used the hydrochemical properties of water to reveal the causes of water quality degradation. The results showed that most samples located downstream of the mine tailings dam were slightly acidic with pH as low as 4.6. Samples with high levels of Na+, Cl−, and could not be isotopically linked to the local geochemistry, but the anthropogenic activities and evaporation were probably responsible for the observed water chemistry. The Piper diagram indicated cations were dominate by Ca and Mg, while anions were dominated by bicarbonates and sulphates. Pb and Hg levels (mean 70.29 and 17.95 μg/L, respectively) were all higher than the World Health Organization (WHO) and Tanzanian drinking water guidelines. Mining activities probably contributed to the observed low pH values and elevated concentration of cyanides, heavy metals, and metalloids. Stable isotope results indicated a vulnerability of the water to recent contamination that could be attributed to anthropogenic activities. Moreover, isotopic studies indicated a flow pattern from the eastern to the western side of the mine study site. Lowland samples were more 3H-enriched than highland ones. The present study concludes that groundwater recharge from recent local precipitation may have an impact on the sources studied.

scholarly journals Evaluation of Groundwater Quality in the Vicinity of Khurrianwala Industrial Zone, Pakistan

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1321 ◽  
Author(s):  
Muhammad Aleem ◽  
Cao Shun ◽  
Chao Li ◽  
Arslan Aslam ◽  
Wu Yang ◽  
...  
Keyword(s):  
Water Quality ◽  
Groundwater Quality ◽  
Anthropogenic Activities ◽  
World Health ◽  
Total Hardness ◽  
Industrial Zone ◽  
High Concentration ◽  
Physico Chemical ◽  
Health Organization ◽  
National Environmental

The industrial augmentation and unguided anthropogenic activities contaminate water sources in most parts of the world especially in developing countries like Pakistan. High concentration of pollutants in groundwater affects human, soil, and crop health badly. The present study was conducted to investigate groundwater quality for drinking and irrigation purposes in an industrial zone of Pakistan. A GIS tool was used to investigate the spatial distribution of different physico-chemical parameters. In this study, the average results exceeding World Health Organization (WHO) and National Environmental Quality Standards (NEQS) were found for pH 7.84, total dissolved solids (TDS) 1492 mg/L, phosphate 0.51 mg/L, dissolved oxygen (DO) 9.92% saturation, F-coli 6.48 colonies/100 mL, Na+ 366 mg/L, HCO3− 771 mg/L, sulfate 251 mg/L, chlorides 427 mg/L, total hardness (as CaCO3) 292 mg/L, electrical conductivity (EC) 2408 μS/cm, iron (Fe) 0.48 mg/L, chrome (Cr) 0.50 mg/L, arsenic (As) 0.04 mg/L, total phosphorus (TP) 0.17 mg/L, sodium adsorption ratio (SAR) 9.76 (in meq/L), residual sodium carbonate (RSC) 9.28 meq/L, % ion balance 14.4 (in meq/L), percentage sodium ion (% Na+) concentration 58.9 meq/L, and water quality index (WQI) 69.0. The trend of cations and anions were (in meq/L) Na > Mg > Ca > K and HCO3 > Cl > CO3 > SO4 respectively. Although the results of the present study showed poor conditions of the groundwater for drinking as WQI but and irrigation purposes as SAR, it needs to improve some more conditions for the provision of safe drinking water and irrigation water quality.

scholarly journals Spatial Distribution of Fluoride in Drinking Water in Dhamar City, Yemen

2021 ◽  
Vol 10 (1) ◽  
pp. 49-63
Author(s):  
Hefdhallah Al Aizari ◽  
Rachida Fegrouche ◽  
Ali Al Aizari ◽  
Saeed S. Albaseer
Keyword(s):  
Drinking Water ◽  
Anthropogenic Activities ◽  
Groundwater Resources ◽  
Principal Component ◽  
World Health ◽  
Residential Areas ◽  
Central Plateau ◽  
The World ◽  
Pca Method ◽  
Health Organization

The fact that groundwater is the only source of drinking water in Yemen mandates strict monitoring of its quality. The aim of this study was to measure the levels of fluoride in the groundwater resources of Dhamar city. Dhamar city is the capital of Dhamar governorate located in the central plateau of Yemen. For this purpose, fluoride content in the groundwater from 16 wells located around Dhamar city was measured. The results showed that 75% of the investigated wells contain fluoride at or below the permissible level set by the World Health Organization (0.5 – 1.5 mg/L), whereas 25% of the wells have relatively higher fluoride concentrations (1.59 – 184 mg/L). The high levels of fluoride have been attributed to the anthropogenic activities in the residential areas near the contaminated wells. Interestingly, some wells contain very low fluoride concentrations (0.30 – 0.50 mg/L).  Data were statistically treated using the principal component analysis (PCA) method to investigate any possible correlations between various factors. PCA shows a high correlation between well depth and its content of fluoride. On the other hand, health problems dominating in the study area necessitate further studies to investigate any correlation with imbalanced fluoride intake.

scholarly journals Microbiological and Physicochemical Characterization of Hospital Effluents before and after Treatment with Two Types of Sawdust

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Rabea Elmountassir ◽  
Bahia Bennani ◽  
Youssef Miyah ◽  
Ahlam Fegousse ◽  
Ghita El Mouhri ◽  
...  
Keyword(s):  
Physicochemical Characterization ◽  
Oxygen Demand ◽  
Fecal Coliforms ◽  
World Health ◽  
Hospital Effluents ◽  
Before And After ◽  
Health Organization ◽  
Filter Bed ◽  
Microbiological Analyses

Physicochemical and microbiological analyses of liquid hospital effluents have demonstrated that they are loaded with organic and inorganic pollutants then discharged into the sewerage networks without treatment. The aim of this study is to suggest an effective solution for their treatment. Column filtration is an adequate method to reduce the pollutant load which makes it possible to have a rate of abatement of 97% and 79% by filtering the pollutant material using sawdust of catia and red sawdust, respectively, with a filter bed height equal to 13 cm. Physicochemical parameters such as chemical oxygen demand, biological oxygen demand, nitrate, ammonia, phosphorus, electrical conductivity and the bacteriological parameters like fecal coliforms, Streptococci, and Staphylococci have been measured. The analysis of heavy metals displays compliance with the World Health Organization standards. The red sawdust and catia sawdust have been characterized by scanning electron microscopy and Fourier-transform infrared spectroscopy.

scholarly journals Physico-Chemical Evaluation of Groundwater in Kuje, Federal Capital Territory, Abuja, Nigeria

1970 ◽  
Vol 12 (1) ◽  
pp. 1-5
Author(s):  
KO Ibrahim ◽  
O Joel ◽  
A Abdulrahman ◽  
SA Bankole
Keyword(s):  
Physical Properties ◽  
Quality Standard ◽  
World Health ◽  
Water Type ◽  
Piper Diagram ◽  
Quality Of Water ◽  
Physico Chemical ◽  
Dug Wells ◽  
Total Dissolved Solid ◽  
Health Organization

This study was done to determine the quality of water from hand-dug wells in Kuje, Federal Capital Territory Abuja Nigeria. The study area lies between latitudes 080 53’ 24’’N and 080 53’ 47’’N and longitude 070 14’ 24’’E and 070 14’ 35’’E. Water from twenty wells were randomly sampled. The physical properties investigated are pH, temperature, total dissolved solid (TDS) and electrical conductivity. The chemical analysis involved determination of the concentration of anions (SO42-, HCO3-, Fl-, CO3-, Cl-, NO3) and cations (Ca2+, Mg+, Na+,K+, Zn+, Fe2+, Cu2+. A piper diagram based on the relative percentages of the ions was plotted for classification according to hydrogeochemical facies of each water sample based on their dominant ions. The Piper diagram indicated Ca2+ and HCO3- as the dominant ions and therefore it is Ca−HCO3 water type. The physical properties of the water were found to be good based on World Health Organization (WHO) guidelines and National Drinking Water Quality Standard (NDWQS) and therefore water in the study area is safe for human consumption.KEYWORDS: groundwater, hydrochemical facies, anion, cation, piper diagram

scholarly journals Insights into SARS-CoV-2, the Coronavirus Underlying COVID-19: Recent Genomic Data and the Development of Reverse Genetics Systems

2020 ◽  
Vol 101 (10) ◽  
pp. 1021-1024
Author(s):  
Severino Jefferson Ribeiro da Silva ◽  
Renata Pessôa Germano Mendes ◽  
Caroline Targino Alves da Silva ◽  
Alessio Lorusso ◽  
Alain Kohl ◽  
...  
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Reverse Genetics ◽  
World Health ◽  
Close Relative ◽  
Sequence Information ◽  
Recombinant Viruses ◽  
Protein Functions ◽  
Genomic Studies ◽  
Health Organization

The emergence and rapid worldwide spread of a novel pandemic of acute respiratory disease – eventually named coronavirus disease 2019 (COVID-19) by the World Health Organization (WHO) – across the human population has raised great concerns. It prompted a mobilization around the globe to study the underlying pathogen, a close relative of severe acute respiratory syndrome coronavirus (SARS-CoV) called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Numerous genome sequences of SARS-CoV-2 are now available and in-depth analyses are advancing. These will allow detailed characterization of sequence and protein functions, including comparative studies. Care should be taken when inferring function from sequence information alone, and reverse genetics systems can be used to unequivocally identify key features. For example, the molecular markers of virulence, host range and transmissibility of SARS-CoV-2 can be compared to those of related viruses in order to shed light on the biology of this emerging pathogen. Here, we summarize some recent insights from genomic studies and strategies for reverse genetics systems to generate recombinant viruses, which will be useful to investigate viral genome properties and evolution.

scholarly journals Mosquito Acetylcholinesterase as a Target for Novel Phenyl-Substituted Carbamates

2019 ◽  
Vol 16 (9) ◽  
pp. 1500
Author(s):  
James M. Mutunga ◽  
Ming Ma ◽  
Qiao-Hong Chen ◽  
Joshua A. Hartsel ◽  
Dawn M. Wong ◽  
...  
Keyword(s):  
Anopheles Gambiae ◽  
Parent Compound ◽  
World Health ◽  
Contact Toxicity ◽  
Ache Inhibitors ◽  
Mosquitocidal Activity ◽  
Health Organization ◽  
Reduced Activity

New insecticides are needed for control of disease-vectoring mosquitoes and this research evaluates the activity of new carbamate acetylcholinesterase (AChE) inhibitors. Biochemical and toxicological characterization of carbamates based on the parent structure of terbam, 3-tert-butylphenyl methylcarbamate, was performed. In vitro enzyme inhibition selectivity (Anopheles gambiae versus human) was assessed by the Ellman assay, as well as the lethality to whole insects by the World Health Organization (WHO) paper contact assay. Bromination at the phenyl C6 position increased inhibitory potency to both AChEs, whereas a 6-iodo substituent led to loss of potency, and both halogenations caused a significant reduction of mosquitocidal activity. Similarly, installation of a hexyl substituent at C6 drastically reduced inhibition of AgAChE, but showed a smaller reduction in the inhibition of hAChE. A series of 4-carboxamido analogs of the parent compound gave reduced activity against AgAChE and generally showed more activity against hAChE than AgAChE. Replacement of the 3-t-buyl group with CF3 resulted in poor anticholinesterase activity, but this compound did have measurable mosquitocidal activity. A series of methyl- and fluoro- analogs of 3-trialkylsilyl compounds were also synthesized, but unfortunately resulted in disappointing activity. Finally, a series of sulfenylated proinsecticides showed poor paper contact toxicity, but one of them had topical activity against adult female Anopheles gambiae. Overall, the analogs prepared here contributed to a better understanding of carbamate structure–activity relationships (SAR), but no new significant leads were generated.

scholarly journals A34 Molecular characterization of Zika virus in Cuba

2019 ◽  
Vol 5 (Supplement_1) ◽  
Author(s):  
P A Martínez ◽  
G Díaz ◽  
E M Castillo ◽  
M Álvarez ◽  
E Santana ◽  
...  
Keyword(s):  
Molecular Characterization ◽  
Latin American ◽  
Zika Virus ◽  
Evolutionary Dynamics ◽  
Western Hemisphere ◽  
World Health ◽  
Published Data ◽  
Reference Laboratory ◽  
Health Organization

Abstract Until now, three genotypes of Zika virus (ZIKV) have been detected (two African lineages and one Asian lineage). After the declaration of Public Health Emergency of International Concern issued by The Pan American Health Organization and the World Health Organization authors from some Latin American countries have identified the Asian genotype as the lineage responsible for the Zika epidemic in the western hemisphere. However, data from the Caribbean are sparse, and there is no published data regarding the genotypes that produced isolated outbreaks in Cuba. Aiming to realize the molecular characterization of ZIKV in Cuba, we will sequence by next-generation sequencing the full genome of the ZIKV identified in samples from Cuban patients of different provinces in which ZIKV produced outbreaks. All samples required for this study have been collected during the molecular surveillance of Arboviral diseases conducted at the National Reference Laboratory at Pedro Kourí Tropical Medicine Institute. Viral RNA will be purified from urine and serum samples collected from patients with confirmed ZIKV infection by real time PCR. Using evolutionary dynamics studies, we will map the spread of a virus or of particular variants in time and space in order to understand how frequently ZIKV has been introduced into Cuba. Moreover, we will evaluate the amino acid diversity of each ZIKV proteins. Further, we will evaluate the population dynamics of ZIKV in samples from patients with varying clinical outcomes. The results will allow us to characterize the ZIKV genome and its evolution into the Cuban population that would also have impact for vaccine development, diagnosis, and pathogenesis studies.

Epidemology: The role of the World Health Organization in the study of influenza

1980 ◽  
Vol 288 (1029) ◽  
pp. 417-421 ◽  
Keyword(s):  
World Health Organization ◽  
Diagnostic Procedures ◽  
Early Years ◽  
World Health ◽  
Isolation And Characterization ◽  
The World ◽  
Pandemic Strains ◽  
Health Organization

The World Health Organization (W.H.O.), since its inception in 1947, has given close attention to influenza. In its early years W.H.O. laid the foundations of its present network of over 100 national influenza centres and collaborating laboratories which today constitute the backbone of its influenza activities. The activities of the network include the isolation and characterization of influenza strains and the early notification of any changes in surface antigens, the preparation of reference reagents, standardization of diagnostic procedures, formulation of requirements for vaccines, training, and collaboration in research. The efficacy of the network has been proved in the 1957, 1968 and 1977 epidemics. Collaborative research organized by W.H.O. has made important contributions to our understanding of the epidemiology of influenza, including the possible role of lower animals as the origin of some pandemic strains. The latter subject is briefly discussed.

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