With 24 million inhabitants and 6.6 million vehicles on the roads, Karachi, Pakistan ranks among the world's most polluted cities due to high levels of fine particulate matter (PM). This study aims to investigate PM mass, seasonal and temporal variability, chemical characterization, source apportionment, and health risk assessment at two urban sites in Karachi.
View Article and Find Full Text PDFDiabetic retinopathy is one of the abnormalities of the retina in which a diabetic patient suffers from severe vision loss due to an affected retina. Proliferative diabetic retinopathy (PDR) is the final and most critical stage of diabetic retinopathy. Abnormal and fragile blood vessels start to grow on the surface of the retina at this stage.
View Article and Find Full Text PDFEliminating hazardous contaminants is a necessity for maintaining a healthy environment on Earth. This work used a sustainable method to create Iron-Zinc nanocomposites with polyvinyl alcohol assistance. Mentha Piperita (mint leaf) extract was used as a reductant in the green synthesis of bimetallic nanocomposites.
View Article and Find Full Text PDFEnvironmental pollution has exacerbated the availability of clean water to mankind. In this study, leaf extract was used for sustainable synthesis of Fe-Zn nanocomposites (IZNC). The instrumental techniques of Fourier transformed infrared (FTIR) spectroscopy, energy dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) were used to determine the structural and chemical composition.
View Article and Find Full Text PDFLike many urban centers in developing countries, the effect of air pollution in Karachi is understudied. The goal of this study was to determine the chemical characterization, temporal and seasonal variability, sources, and health impacts of fine particulate matter (PM) in Karachi, Pakistan. Daily samples of PM were collected using a low-volume air sampler at two different sites (Makro and Karachi University) over the four seasons between October 2009 and August 2010.
View Article and Find Full Text PDFEnviron Monit Assess
January 2023
Karachi, Pakistan, is a priority site for air pollution research due to high emissions of air pollutants from vehicular traffic, industrial activities, and biomass burning, as well as rapid growth in population. The objectives of this study were to investigate the levels of gaseous pollutants (NO, NO, O, HNO, and SO) in Karachi, to determine temporal and seasonal variations, to compare Karachi's air quality with other urban centers, to identify relationships with meteorological conditions, to identify source characterization, and to perform a backward-in-time trajectory analysis and a health impact assessment. Daily samples of gaseous pollutants were collected for six consecutive weeks in each of the four seasons for a year.
View Article and Find Full Text PDFMass gathering events commonly encounter environmental challenges that necessitate assurance of water quality and food security. The current outbreak of the coronavirus disease 2019 (COVID-19) call for maintaining safe drinking water supply and providing assessment tools of drinking water quality to avoid contamination in water sources or distribution networks. Arid environmental conditions also add more stress on supplied water to mass gathering events.
View Article and Find Full Text PDFTo reduce the spread of COVID-19, lockdowns were implemented in almost every single country in the world including Saudi Arabia. In this paper, the effect of COVID-19 lockdown on O, NO, and PM in Makkah was analysed using air quality and meteorology data from five sites. Two approaches were employed: (a) comparing raw measured concentrations for the lockdown period in 2019 and 2020; and (b) comparing weather-corrected concentrations estimated by the machine learning approach with observed concentrations during the lockdown period.
View Article and Find Full Text PDFIn this paper, the emission sources of PM10 are characterised by analysing its trace elements (TE) and ions contents. PM10 samples were collected for a year (2019−2020) at five sites and analysed. PM10 speciated data were analysed using graphical visualization, correlation analysis, generalised additive model (GAM), and positive matrix factorization (PMF).
View Article and Find Full Text PDFThe vehicular industry is looking for continuous challenges to develop the sustainability of its manufacturing, maintenance processes, and vehicle emissions due to marketability, environmental, economic, and policy concerns. The present study focuses on the impact of these processes on the environment. In Pakistan, most of the auto-body refinishing processes are carried out in an open atmosphere.
View Article and Find Full Text PDFA simple, accurate and precise RP-HPLC method was developed for the simultaneous determination of chloroquine, pyrimethamine and cetirizine hydrochloride concentrations in bulk drug and human serum. The assay was performed using a mobile phase of methanol: water (70:30) at pH of 2.8 ± 0.
View Article and Find Full Text PDFIn the present study, occurrence of arsenic (As) and lead (Pb) is reported in rural and urban household dust (floor and AC filter dust) of the Kingdom of Saudi Arabia (KSA). Several studies have found concerning concentrations of these toxic metals in indoor dust from different countries, but data from this region is missing. The association between studied toxic metals and different socioeconomic parameters was investigated.
View Article and Find Full Text PDFThis study presents a detailed measurement of indoor and outdoor terrestrial gamma radiation levels in different cities of Pakistan. The measurements covered dwellings in 27 cities, covering all provinces and region of Azad Kashmir. Most of the houses were of attached type, made of brick walls and concrete roofs.
View Article and Find Full Text PDFChemical phase and distribution of natural radionuclides (226Ra, 232Th and 40K) were determined for sand samples collected from ten different beaches of Karachi. All samples, except one, were identified with major and minor phases as SiO2 and CaCO3, respectively. The average activity concentrations were 24.
View Article and Find Full Text PDFAir pollution remains a major global public health and environmental issue. We assessed the levels of PM and delineated the major sources in Makkah, Saudi Arabia. Fine particulate matter (PM) sampling was performed from February 26, 2014-January 27, 2015 in four cycles/seasons.
View Article and Find Full Text PDFHealth effects linked to PM, have been extensively studied in developed countries of Europe and N. America. However, little has been done in Saudi Arabia and the Middle East.
View Article and Find Full Text PDFTo assess cardiopulmonary morbidity associated with daily exposures to PM2.5 in Western Coast of Saudi Arabia. Methods: We monitored 24-h PM2.
View Article and Find Full Text PDFThe Arabian Peninsula experiences severe air pollution, the extent and sources of which are poorly documented. Each year in Saudi Arabia this situation is intensified during Hajj, the Holy Pilgrimage of Islam that draws millions of pilgrims to Mecca. An initial study of air quality in Mecca and surrounding holy sites during the 2012 Hajj (October 24-27) revealed strongly elevated levels of the combustion tracer carbon monoxide (CO, up to 57 ppmv) and volatile organic compounds (VOCs) along the pilgrimage route-especially in the tunnels of Mecca-that are a concern for human health.
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