Study of Surface Morphology, Elemental Composition and Sources of Airborne Fine Particulate Matter in Agbara Industrial Estate, Nigeria

Ambient atmospheric fine particle emission contribution to industrial pollution load is hard to quantify due to absence of air quality monitoring stations and difficulties in assessing suitable analytical instruments. Therefore, to keep abreast of air quality information, the use of physicochemical signatures to assess the sources of elements associated with fine particulate matter in Agabra Industrial Estate was explored with Scanning Electron Microscopy (SEM) coupled with Energy Dispersive X-ray (EDX) and Principal Component Analysis (PCA). A greater proportion of Si and C were observed in the particles amongst other detected elements by EDX. Morphology results by SEM confirmed soot, alumino silicate and irregular shape mineral particles as the most common inhalable particles. Prominent among emission sources identified are industries, automobile exhaust, fugitive dust and solid waste combustion. The research suggests that adequate public awareness, industrial compliance, vehicle emission control, smooth operation of municipal solid waste incineration and government regulation will significantly reduce fine particulate pollution

Chemical Speciation and Health Risk Assessment of Fine Particulate Bound Trace Metals Emitted from Ota Industrial Estate, Nigeria

In this study carcinogenic and non-carcinogenic health risk due to exposure to PM2.5-bound trace metals from an industrial area in Southwestern Nigeria was estimated. A four-step chemical sequential extraction procedure was employed for the chemical extraction of arsenic (As), cadmium (Cd), chromium (Cr) copper (Cu), manganese (Mn), nickel (Ni), and zinc (Zn). Samples were analyzed using inductively coupled plasma mass spectrometry (ICPMS). Results reveal Cr and Cu as the most dominant exchangeable fraction metals, indicating possibility of their being readily soluble once PM2.5 is inhaled. Cd and Cr record the highest bioavailability index of 0.7. The cumulative lifetime cancer risks due to inhalation exposure for adults (4.25×10-2), children 1-6 years old (4.87×10-3), and children 6-18 years old (1.46×10-2) were found above Environmental Protection Agency’s acceptable range of 1×10-6 to 1×10-4. The hazard index values for all studied trace metals suggest significant potential for noncarcinogenic health risks to adults and children. The choice of chemical speciation as an essential tool in facilitating a better predictive insight on metal bioavailability and toxicity for immediate remediation action has been highlighted

Characterization of Airborne Fine Particulate Matter (PM2.5) and Its Air Quality Implications in Ogun State, Nigeria

Atmospheric aerosols pose a serious threat to environmental quality and health of the public. Several studies in Nigeria have documented the pollution levels from coarse particles but very few have elucidated the nature of the fine particles in the context of air quality index. Our investigation therefore focused on air quality index in relation to ambient fine particulate and composition of PM2.5 collected from an industrial area (IA) and a university community (UC) in Ogun State, Nigeria. The PM2.5 samples were collected using Environtech gravimetric sampler according to standard methods. The morphology and elemental composition of PM2.5 were assessed by scanning electron microscope (SEM) coupled with an energy dispersive X-ray (EDX). The SEM images of fine particles indicated the following clustered groups: soot particles, alumino silicates, and mixture of alumino silicate with soot. Energy dispersive X-ray spectra showed nine most abundant elemental composition in all samples. Possible source emissions of elements identified by principal component analysis are industrial processes, vehicle emissions, crustal dust, fuel-oil and biomass burning. Air quality index (AQI), for particulate pollution was calculated for each location. Fine particle pollution indices scaled from 51 to 500, reflecting six out of the seven AQI categories in varying proportions. The absence of 0 to 50 gradation representing the good AQI category is conspicuously highlighted. Results indicate that most AQI values were above 100. Possible adverse health concerns mostly for the vulnerable populations are indicated considering the unhealthy air quality state of studied locations

High performance valuation of CO2 gas separation ceramic membrane system.

Atmospheric carbon dioxide emissions are considered as the greatest environmental challenge the world is facing today. The tasks to control the emissions include the recovery of CO2 from flue gas. This concern has been improved due to recent advances in materials process engineering resulting in the development of inorganic gas separation membranes with excellent thermal and mechanical stability required for most gas separations. This paper therefore evaluates the performance of a highly selective inorganic membrane for CO2 recovery applications. Analysis of results obtained is in agreement with experimental literature data. Further results show the prediction performance of the membranes for gas separation and the future direction of research. The materials selection and the membrane preparation techniques are discussed. Method of improving the interface defects in the membrane and its effect on the separation performance has also been reviewed and in addition advances to totally exploit the potential usage of this innovative membrane

Chemical speciation and health risks of airborne heavy metals around an industrial community in Nigeria.

Quantification of PM2.5 (particulate matter <2.5 μm) bound heavy metals and their potential health risks were carried out around a cement manufacturing company in Ewekoro, Nigeria. The PM2.5 samples were collected using Environtech gravimetric sampler. A four-staged sequential extraction procedure was used to fractionate PM2.5 bound chromium (Cr), lead (Pb), aluminum (Al), copper (Cu), and silver (Ag), and further analyzed using inductively coupled plasma mass spectrometry. Chemical speciation results reveal bioavailable levels of Pb (4.05 μg/m3), Cr (10.75 μg/m3), Al (16.47 μg/m3), Cu (4.38E-01 μg/m3), and Ag (1.22E-02 μg/m3) in the airborne particulates. Pb and Cr levels exceeded the World Health Organization allowable limit of 0.5 and 2.5E-05 μg/m3, respectively. The labile phases showed strong indication of the presence of Cr and Cu metal. Excess cancer risks exposure for adults, outdoor workers and children were higher than the acceptable risk target level of 1E-06. Noncarcinogenic health risk estimated using hazard quotients (HQs) and hazard indices (HIs) showed ingestion route within the safe level of HI <1 implying no adverse effect while inhalation route exceeded the safe level for all receptors. Enforcement of pollution control by authorized agencies, and screening of greenbelts as sinks for air pollutants is strongly recommended

Weakly-supervised learning for image-based classification of primary melanomas into genomic immune subgroups

Determining early-stage prognostic markers and stratifying patients for effective treatment are two key challenges for improving outcomes for melanoma patients. Previous studies have used tumour transcriptome data to stratify patients into immune subgroups, which were associated with differential melanoma specific survival and potential treatment strategies. However, acquiring transcriptome data is a time-consuming and costly process. Moreover, it is not routinely used in the current clinical workflow. Here we attempt to overcome this by developing deep learning models to classify gigapixel H&E stained pathology slides, which are well established in clinical workflows, into these immune subgroups. Previous subtyping approaches have employed supervised learning which requires fully annotated data, or have only examined single genetic mutations in melanoma patients. We leverage a multiple-instance learning approach, which only requires slide-level labels and uses an attention mechanism to highlight regions of high importance to the classification. Moreover, we show that pathology-specific self-supervised models generate better representations compared to pathology-agnostic models for improving our model performance, achieving a mean AUC of 0.76 for classifying histopathology images as high or low immune subgroups. We anticipate that this method may allow us to find new biomarkers of high importance and could act as a tool for clinicians to infer the immune landscape of tumours and stratify patients, without needing to carry out additional expensive genetic tests

Assessment of differentially methylated loci in individuals with end-stage kidney disease attributed to diabetic kidney disease : an exploratory study

Publisher Copyright: © 2021, The Author(s).Background: A subset of individuals with type 1 diabetes mellitus (T1DM) are predisposed to developing diabetic kidney disease (DKD), the most common cause globally of end-stage kidney disease (ESKD). Emerging evidence suggests epigenetic changes in DNA methylation may have a causal role in both T1DM and DKD. The aim of this exploratory investigation was to assess differences in blood-derived DNA methylation patterns between individuals with T1DM-ESKD and individuals with long-duration T1DM but no evidence of kidney disease upon repeated testing to identify potential blood-based biomarkers. Blood-derived DNA from individuals (107 cases, 253 controls and 14 experimental controls) were bisulphite treated before DNA methylation patterns from both groups were generated and analysed using Illumina’s Infinium MethylationEPIC BeadChip arrays (n = 862,927 sites). Differentially methylated CpG sites (dmCpGs) were identified (false discovery rate adjusted p ≤ × 10–8 and fold change ± 2) by comparing methylation levels between ESKD cases and T1DM controls at single site resolution. Gene annotation and functionality was investigated to enrich and rank methylated regions associated with ESKD in T1DM. Results: Top-ranked genes within which several dmCpGs were located and supported by functional data with methylation look-ups in other cohorts include: AFF3, ARID5B, CUX1, ELMO1, FKBP5, HDAC4, ITGAL, LY9, PIM1, RUNX3, SEPTIN9 and UPF3A. Top-ranked enrichment pathways included pathways in cancer, TGF-β signalling and Th17 cell differentiation. Conclusions: Epigenetic alterations provide a dynamic link between an individual’s genetic background and their environmental exposures. This robust evaluation of DNA methylation in carefully phenotyped individuals has identified biomarkers associated with ESKD, revealing several genes and implicated key pathways associated with ESKD in individuals with T1DM.Peer reviewe

Maresins: novel macrophage mediators with potent antiinflammatory and proresolving actions

The endogenous cellular and molecular mechanisms that control acute inflammation and its resolution are of wide interest. Using self-resolving inflammatory exudates and lipidomics, we have identified a new pathway involving biosynthesis of potent antiinflammatory and proresolving mediators from the essential fatty acid docosahexaenoic acid (DHA) by macrophages (MΦs). During the resolution of mouse peritonitis, exudates accumulated both 17-hydroxydocosahexaenoic acid, a known marker of 17S-D series resolvin (Rv) and protectin biosynthesis, and 14S-hydroxydocosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid from endogenous DHA. Addition of either DHA or 14S-hydroperoxydocosa-4Z,7Z,10Z,12E,16Z,19Z-hexaenoic acid to activated MΦs converted these substrates to novel dihydroxy-containing products that possessed potent antiinflammatory and proresolving activity with a potency similar to resolvin E1, 5S,12R,18R-trihydroxyeicosa-6Z,8E,10E,14Z,16E-pentaenoic acid, and protectin D1, 10R,17S-dihydroxydocosa-4Z,7Z,11E,13E,15Z,19Z-hexaenoic acid. Stable isotope incorporation, intermediate trapping, and characterization of physical and biological properties of the products demonstrated a novel 14-lipoxygenase pathway, generating bioactive 7,14-dihydroxydocosa-4Z,8,10,12,16Z,19Z-hexaenoic acid, coined MΦ mediator in resolving inflammation (maresin), which enhances resolution. These findings suggest that maresins and this new metabolome may be involved in some of the beneficial actions of DHA and MΦs in tissue homeostasis, inflammation resolution, wound healing, and host defense