Polycyclic aromatic hydrocarbons within the vicinity of a scrap-iron smelting plant: indoor-outdoor and seasonal pattern, source, and exposure risk assessment.

The growing demand for ferrous metals and abundant scrap materials has fueled Nigeria's scrap-iron smelting industry, leading to hazardous pollutant emissions. This study investigated the concentrations, seasonal and indoor-outdoor variations, origins, and health impacts of polycyclic aromatic hydrocarbons (PAHs) in dust samples around a scrap-iron smelting facility. Analyses of dust samples revealed that high molecular weight PAHs (HMWPAHs) dominated during both seasons, with 5-ring PAHs (34%) contributing most during the rainy season and 3-ring PAHs (36%) during the dry season.

Concentration and sources of persistent organic pollutants within the vicinity of a scrap-iron smelting plant: Seasonal pattern and health risk assessment.

Polychlorinated biphenyls (PCBs) are a class of ubiquitous and significant synthetic organic chemicals that pose deleterious threats to the environment and human health. This study examined the concentration, indoor-outdoor and seasonal change, sources, and health effects of PCBs in particulate-bound dust near a scrap iron recycling plant. PCBs levels were determined in samples using gas chromatograph mass spectrometer.

Quantifications and predictions of sectoral pollutants emissions in Nigeria from 1980 to 2050.

The fast-economic development and population growth in Nigeria have resulted in huge quantities of air pollutants emission which have implications on the environment. Detailed sectoral emission inventory to serve as the basis for policy formation to mitigate the condition is still lacking. This study builds detailed sectoral emission inventory using the emission factor approach to estimates various pollutant emissions from different sources.

Source identification and health risk assessments of heavy metals in indoor dusts of Ilorin, North central Nigeria.

Background And Purpose: Exposure to heavy metals (HMs) in indoor dusts is a serious public concern that is linked to a myriad of deleterious health outcomes. The objectives of this study are to estimate the contamination levels of HMs in indoor dusts of different residential areas in Ilorin, Nigeria; identify HMs sources in different residential areas; and evaluate human health risks of HMs in selected residential areas.

Methods: Indoor dust sampling was conducted in ten randomly selected from low, medium and high population density residential areas of Ilorin, Nigeria.

Polycyclic aromatic hydrocarbons in road dusts of a densely populated African city: spatial and seasonal distribution, source, and risk assessment.

Road dust is a principal source and depository of polycyclic aromatic hydrocarbons (PAHs) in many urban areas of the world. Hence, this study probed the spatial and seasonal pattern, sources, and related cancer health risks of PAHs in the road dusts sampled at ten traffic intersection (TIs) of a model African city. Mixed PAHs sources were ascertained using the diagnostic ratios and positive matrix factorization (PMF) model.

Indoor transmission dynamics of expired SARS-CoV-2 virus in a model African hospital ward.

Unlabelled: Cough and sneeze droplets' interactions with indoor air of a typical hospital clinic that could be majorly found in developing African countries were studied to investigate the effectiveness of existing guidelines/protocols being adopted in the control of the widespread coronavirus disease (COVID-19) transmission. The influences of indoor air velocity, the type, size distribution, residence time in air, and trajectory of the droplets, were all considered while interrogating the effectiveness of physical distancing measures, the use of face covers, cautionary activities of the general public, and the plausibility of community spread of the SARS-CoV-2 virus through airborne transmission. Series of 3-D, coupled, discrete phase models (DPM) were implemented in the numerical studies.

Emission factors of some common grass species in West Africa.

Frequent burnings occurring in the grasslands of the West African region during the dry seasons largely contribute to emissions of trace gases and particulates being released into the ambient environment, which has significantly impacted both regional and global climate patterns. Burning potentials of forty different grassland biomes were examined by determining their Net Heating Value (NHV) and Total Organic Carbon (TOC). Simulations of the field operations which involve open burning were performed in the laboratory using a fabricated combustion chamber for the determination of emission factors.

Evaporation rates and pollutants emission from heated cooking oils and influencing factors.

The heating of edible oils during cooking activities promotes the emissions of pollutants that have adverse impacts on the health of humans. This study investigated the evaporative emissions of fifteen (15) commonly used cooking oils. Split-plot experimental design under the response surface methodology framework was used to study singular and interaction effects of influencing parameters (temperature, volume of cooking oil and time) on cooking oil evaporation rate and pollutants emissions (i.

Landfill air and odour emissions from an integrated waste management facility.

A mixture of gases and obnoxious odours are major components of landfill emission. A dispersion modelling on air pollutants and odour emissions anticipated from a proposed Integrated Waste Management Facility was conducted considering five operating scenarios. Impacts of the predicted ground level concentrations of air pollutants (including carbon monoxide, CO; oxides of nitrogen, NO; sulphur dioxide, SO; particulate matter, PM and hydrocarbons, HC) and odour on ambient air quality were investigated using the 10-min 1 OU/m odour limit, CH Lower Explosive Limit (LEL) and the daily limits of CO, NOx, SO, PM and HC.

Modeling of an activated sludge process for effluent prediction-a comparative study using ANFIS and GLM regression.

In this paper, nonlinear system identification of the activated sludge process in an industrial wastewater treatment plant was completed using adaptive neuro-fuzzy inference system (ANFIS) and generalized linear model (GLM) regression. Predictive models of the effluent chemical and 5-day biochemical oxygen demands were developed from measured past inputs and outputs. From a set of candidates, least absolute shrinkage and selection operator (LASSO), and a fuzzy brute-force search were utilized in selecting the best combination of regressors for the GLMs and ANFIS models respectively.

Particulate matter concentration levels during intense haze event in an urban environment.

This study assessed concentration levels of particulate matter (PM) in the ambient environment of Ilorin metropolis, Nigeria, during haze episodes. Meteorological data (wind speed and direction, rainfall data, sunshine data, relative humidity and temperature) were obtained. Aerocet 531S particle counter (MetOne Instruments, USA) was used to measure four mass concentration ranges of PM (PM, PM, PM and the total suspended particles (TSP)) in 10 locations taking into consideration land use patterns.