Joshua Edokpayi - Profile on Academia.edu (original) (raw)

Papers by Joshua Edokpayi

A spatial approach to assessing PM _2.5 exposure level of a brickmaking community in South Africa

Journal of the Air & Waste Management Association, Mar 21, 2024

Applied water science, Feb 27, 2024

In recent times, dyes such as Congo Red have proven to be resilient environmental pollutants affe... more In recent times, dyes such as Congo Red have proven to be resilient environmental pollutants affecting freshwater portability among other media. Its toxicity to humans, animals and plant life is both a cause of concern and a motivation to prioritize decontamination. Many materials have been explored for the removal of this pollutant via adsorption; however, there are notable areas of improvement. Dicerocaryum eriocarpum (DE) seed is a non-toxic, cost-effective plant material which is possible as a sorbent and has not been reported in Congo Red sequestration. This research is therefore based on the removal of Congo Red dye from aqueous solution using raw (RDE) and citric acid-modified DE (CDE). The sorbents were characterized before and after sorption using various characterization techniques such as FTIR, EDS, SEM and BET. The effects of contact time, adsorbent dosage, concentration, pH and temperature were optimized during the experiment. According to experimental findings, modification with citric acid resulted in a reduction of the equilibration interval from 90 to 60 min. Sorption effectiveness increased with an increase in temperature for CDE but a decrease in temperature for RDE. The equilibrium data were best described by the Langmuir isotherm with maximum sorption capacity (q max ) of 51.02 mg/g and 53.19 mg/g for RDE and CDE, respectively. Pseudo-second-order model better suited the kinetic data, while thermodynamic analysis revealed a spontaneous sorption process. Five cycles of desorption experiments using 0.1 M NaOH revealed that the regenerated sorbent effectively removed CR dye for the first three cycles at comparable efficiency to the virgin samples. This study therefore supports the use of DE seed as an easily accessible and efficient sorbent for remediation of harmful dyes from water.

Quantification and Modelling of Methane and Carbon Dioxide Surface Emissions from a South African Landfill

Frontiers in Public Health, Dec 18, 2023

Introduction: Wastewater-based genomic surveillance of severe acute respiratory syndrome coronavi... more Introduction: Wastewater-based genomic surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) provides a comprehensive approach to characterize evolutionary patterns and distribution of viral types in a population. This study documents the molecular epidemiology of SARS-CoV-2, in Northern South Africa, from January 2021 to May 2022. Methodology: A total of 487 wastewater samples were collected from the influent of eight wastewater treatment facilities and tested for SARS-CoV-2 RNA using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). SARS-CoV-2 positive samples with genome copies/mL ≥1,500 were subjected to allele-specific genotyping (ASG) targeting the Spike protein; 75 SARS-CoV-2 positive samples were subjected to whole genome sequencing (WGS) on the ATOPlex platform. Variants of concern (VoC) and lineages were assigned using the Nextclade and PangoLIN Software. Concordance for VoC between ASG and WGS analyses was determined. Sequence relationship was determined by phylogenetic analysis. Results: Seventy-five percent (365/487) of the influent samples were positive for SARS-CoV-2 RNA. Delta and Omicron VoC were more predominant at a prevalence of 45 and 32%, respectively, and they were detected as early as January and February 2021, while Beta VoC was least detected at a prevalence of 5%. A total of 11/60 (18%) sequences were assigned lineages and clades only, but not a specific VoC name. Phylogenetic analysis was used to investigate the relationship of these sequences to other study sequences, and further characterize them. Concordance in variant assignment between ASG and WGS was seen in 51.2% of the study sequences. There was more intra-variant diversity among Beta VoC

Exploring the Dichotomy: Shotgun Metagenomics Reveals Diversity of Beneficial and Pathogenic Protist Community in South African Subtropical Arid Wetlands

Scientific Reports

This study focuses on the evaluation of trace metals as well as microbial contamination of ground... more This study focuses on the evaluation of trace metals as well as microbial contamination of groundwater. Groundwater samples were collected from 17 boreholes. The microbial quality was tested using membrane filtration method. Higher levels of contamination for both E. coli and total coliform was recorded in the wet season. Majority of the boreholes had nitrate levels above the regulatory guideline value of the World health Organisation and the South African National Standards. The water type was established by Piper plot which showed the predominance of a magnesium bicarbonate water type, with alkaline earth metals dominating the alkali metals, as well as the weaker acids (bicarbonates) dominating the stronger ones (Sulphates and chlorides). Most of the trace metals detected were in compliance with the regulatory standard except for aluminium (0.41–0.88 mg/L). The hazard quotient and Hazard indice exceeded 1 mostly for children in both season which implies a possible non-carcinogenic...

The Open Microbiology Journal, Feb 28, 2018

Background: Access to clean and safe drinking water is still a problem in developing countries an... more Background: Access to clean and safe drinking water is still a problem in developing countries and more pronounced in rural areas. Due to erratic supply of potable, rural dwellers often seek for an alternative source of water to meet their basic water needs. The objective of this study is to monitor the microbiological and physicochemical water quality parameters of Nzhelele River which is a major alternative source of drinking water to villages along its course in Limpopo province of South Africa. Methods: Membrane filtration method was employed in evaluating the levels of E. coli and Enterococci in the river water from January-June, 2014. Specialized multimeter was used to measure the pH, electrical conductivity and turbidity of the river water. Ion Chromatograph was used to measure major anions such as fluoride, chloride, nitrate and sulphate in the water. Results: High levels of E. coli (1 x 10 2-8 x 10 4 cfu/100 mL) and enterococci (1 x 10 2-5.7 x 10 3 cfu/100 mL) were found in the river water and exceeded their permissible limits of 0 cfu/100 mL for drinking water. Turbidity values ranged from 1.12-739.9 NTU. The pH, electrical conductivity, chloride, fluoride, nitrate and sulphate levels were below their permissible limits for drinking water. Conclusion: The river water is contaminated with faecal organisms and is unfit for drinking purposes. However, the levels of the major anions accessed were within the permissible limits of drinking water.

Estimation of landfill gas production and potential utilization in a South Africa landfill

Journal of the Air & Waste Management Association, Jun 21, 2022

Determination of Polycyclic Aromatic Hydrocarbons in Rivers, Sediments and Wastewater Effluents in Vhembe District of South Africa Using GC-TOF-MS

World Academy of Science, Engineering and Technology, International Journal of Environmental and Ecological Engineering, Feb 22, 2016

Cyanotoxins in groundwater; occurrence, potential sources, health impacts and knowledge gap for public health

Toxicon, Apr 1, 2023

Sustainability, Mar 30, 2023

This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY

Chemistry Central Journal, Jan 12, 2018

Groundwater is considered as good alternative to potable water because of its low turbidity and p... more Groundwater is considered as good alternative to potable water because of its low turbidity and perceived low contamination. The study assessed the physio-chemical and heavy metals concentrations in eight randomly selected boreholes water at Muledane village in Limpopo Province of South Africa and the results were compared with South African National standard permissible limit. The impacts of heavy metals on human health was further determined by performing quantitative risk assessment through ingestion and dermal adsorption of heavy metals separately for adults and children in order to estimate the magnitude of heavy metals in the borehole samples. Parameters such as turbidity, nitrate, iron, manganese and chromium in some investigated boreholes did not comply with standard limits sets for domestic water use. Multivariate analyses using principal component analysis and hierarchical cluster analysis revealed natural and anthropogenic activities as sources of heavy metal contamination in the borehole water samples. The calculated non-carcinogenic effects using hazard quotient toxicity potential, cumulative hazard index and chronic daily intake of groundwater through ingestion and dermal adsorption pathways were less than a unity, which showed that consumption of the water could pose little or no significant health risk. However, maximum estimated values for an individual exceeded the risk limit of 10 −6 and 10 −4 with the highest estimated carcinogenic exposure risk (CR ing) for Cr and Pb in the groundwater. This could pose potential health risk to both adults and children in the investigated area. Therefore, precaution needs to be taken to avoid potential CR ing of people in Muledane area especially, children using the borehole water.

Scientific Reports, Apr 11, 2022

Water quality has been linked to health outcomes across the world. This study evaluated the physi... more Water quality has been linked to health outcomes across the world. This study evaluated the physicochemical and bacteriological quality of drinking water supplied by the municipality from source to the point of use at Thulamela municipality, Limpopo Province, South Africa; assessed the community practices regarding collection and storage of water and determined the human health risks associated with consumption of the water. Assessment of water quality was carried out on 114 samples. Questionnaires were used to determine the community's practices of water transportation from source to the point-of-use and storage activities. Many of the households reported constant water supply interruptions and the majority (92.2%) do not treat their water before use. While E. coli and total coliform were not detected in the water samples at source (dam), most of the samples from the street taps and at the point of use (household storage containers) were found to be contaminated with high levels of E. coli and total coliform. The levels of E. coli and total coliform detected during the wet season were higher than the levels detected during the dry season. Trace metals' levels in the drinking water samples were within permissible range of both the South African National Standards and World Health Organisation. The calculated non-carcinogenic effects using hazard quotient toxicity potential and cumulative hazard index of drinking water through ingestion and dermal pathways were less than unity, implying that consumption of the water could pose no significant non-carcinogenic health risk. Intermittent interruption in municipal water supply and certain water transportation and storage practices by community members increase the risk of water contamination. We recommend a more consistent supply of treated municipal water in Limpopo province and training of residents on hygienic practices of transportation and storage of drinking water from the source to the point of use.

Morphological Analysis of an Organic-rich Shale: Implication for Potential Gas Energy Generation, Witbank Coalfield, South Africa

Microscopy and Microanalysis

Wastewater-Based Surveillance of Sars-Cov-2 and Description of Variants of Concern in Northern South Africa: Observations from 2021 – 2022

Frontiers in Microbiology

Enteric viruses are common waterborne pathogens found in environmental water bodies contaminated ... more Enteric viruses are common waterborne pathogens found in environmental water bodies contaminated with either raw or partially treated sewage discharge. Examples of these viruses include adenovirus, rotavirus, noroviruses, and other caliciviruses and enteroviruses like coxsackievirus and polioviruses. They have been linked with gastroenteritis, while some enteric viruses have also been implicated in more severe infections such as encephalitis, meningitis, hepatitis (hepatitis A and E viruses), cancer (polyomavirus), and myocarditis (enteroviruses). Therefore, this review presents information on the occurrence of enteric viruses of public health importance, diseases associated with human exposure to enteric viruses, assessment of their presence in contaminated water, and their removal in water and wastewater sources. In order to prevent illnesses associated with human exposure to viral contaminated water, we suggest the regular viral monitoring of treated wastewater before discharging...

Journal of Materials & Environmental Sustainability Research

Advanced material science has resulted in materials with atomic-scale dimensions whose tremendous... more Advanced material science has resulted in materials with atomic-scale dimensions whose tremendous application includes filtration, drug delivery, membrane, sensor, and encapsulation. Nanoporous fibre has been formed using temperature-induced phase separation (TIPS) and vapour-induced phase separation (VIPS) mechanism, but polymer concentration has been underestimated in the electrospinning parameter. This work aims at showcasing the effect of electrospinning parameters including polymer concentration and resultant phases on pore formation on fibre. Pore formation in electrospun fibre was carried out by electrospinning expanded polystyrene (EPS). The surface morphology of the resulting nanoporous fibre was characterized with Scanning Electron Microscope (SEM) while the pore distribution was analyzed with a BET (Brunauer, Emmet, Teller) micromeritics analyzer. From the result, an increased concentration of polymer from 10 % decreased bead population to zero, meanwhile, bombardment wit...

International Conference on Sustainable Management of Natural Resources (ICSMNR) : Proceedings of the First International Conference in Sustainable Management of Natural Resources: 15th - 17th October 2018, Bolivia Lodge, Polokwane, South Africa

Improving Antibacterial Performance of Household Water Filters with a Silver-Embedded Ceramic Tablet

Journal of Environmental Engineering

African Journal of Infectious Diseases, 2017

Background: The Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) ... more Background: The Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) are still global health problems. This study was conducted to describe the attitudes of female street vendors (FSV) in Thohoyandou, Vhembe district, towards HIV/AIDS and those infected with the virus. Materials and methods: A quantitative, cross-sectional survey design was adopted. Data were collected by means of a structured, self-administered questionnaire and analyzed using the Statistical Package for Social Sciences (SPSS) version 20.0. Results: Majority (85.0%) of the participants had completed secondary education, 46.7% were single and 41.5% were aged 40 and above. Most of them (90.5%) indicated that they would accept to do a voluntary HIV test. Fear of stigmatization ranked highest among the reasons given by those not in favour of testing. Whilst 91.0% of the participants reported that they can stay in the same house with a person who is HIV positive and 88.5% said they would not have sex in exchange for money, only 57.5% indicated that they would agree to take antiretroviral drugs if they tested positive in pregnancy. The level of education was found to be significantly associated (p-value = 0.000) with the type of attitude shown towards HIV and those infected. Conclusion: It is recommended that HIV information providers and health workers in South Africa pay more attention to enlightening women about the importance of taking antiretroviral drugs in pregnancy to reduce the incidence of mother-to-child transmission of HIV.