The Subsurface Urban Heat Island Intensity in Enugu Urban, Nigeria
Francis Chibuike Nwalozie,
Ifeanyi Christian Enete
Issue:
Volume 11, Issue 4, July 2023
Pages:
57-62
Received:
9 January 2023
Accepted:
13 February 2023
Published:
24 July 2023
Abstract: Urbanisation over the past hundred years has caused environmental and thermal influences underground; yet little knowledge exists about subsurface warming in Enugu, despite previous studies confirming the presence of urban heat island in the area. This study analysed the subsurface urban heat island intensity in Enugu urban, using secondary urban subsoil temperature data set that was sourced from the Nigerian Meteorological Agency over 21 years (2000-2020). With an application known as grid, the rural subsoil temperature data set was gotten by downscaling that of the urban which is 40 km away. The statistical technique employed was Welch’s t-test. The study showed that the annual mean urban subsoil temperatures were generally warmer than that of the rural subsoil temperatures, with a mean difference or subsurface urban heat island intensity of 0.4°C. From the study, it was clear that the urban heat island effect occurred in the subsurface in Enugu, as it does above the ground. This study, to define urban and rural better, suggests that the use of the Local Climate Zone classification scheme should be considered in further research. A joint investigation of the three urban heat island categories in Enugu should also receive top priority in subsequent studies.
Abstract: Urbanisation over the past hundred years has caused environmental and thermal influences underground; yet little knowledge exists about subsurface warming in Enugu, despite previous studies confirming the presence of urban heat island in the area. This study analysed the subsurface urban heat island intensity in Enugu urban, using secondary urban s...
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Dietary Exposure, Risk and Toxicological Evaluation of Polycyclic Aromatic Hydrocarbons in Some Grains (Beans, Soya Beans, Corn, Guinea Corn) from Markets in Nigeria
Odika Ifeoma Maryrose,
Odidika Collins Chibuzor,
Muobike Chidinma Malinda,
Okoye Chukwuma Obiajulu
Issue:
Volume 11, Issue 4, July 2023
Pages:
63-73
Received:
11 July 2023
Accepted:
28 July 2023
Published:
22 August 2023
Abstract: This study aimed at determining the; quantity of polycyclic aromatic hydrocarbons, PAHs in beans, soyabeans, corn and guinea corn consumed in South East Nigeria; source of emission; daily intake amount and health risks associated with their consumption among adult male and female individuals. Thirty six grain samples from markets in Eastern part of Nigeria were analyzed of 16 PAHs. The extraction and analysis were respectively by sonication and gas chromatography coupled flame ionization detector, GC-FID. The limif of detection, LOD and limit of quantification, LOQ obtained ranged from 0.03 × 10-3 µg/dm3 - 0.09 × 10-3 µg/dm3 and 0.09 x 10-3 µg/dm3 - 0.25 × 10-3 µg/dm3 respectively. The average recoveries ranged from 94.0% - 99.2%. The ∑16 PAHs concentrations (× 10-2µg/kg) detected ranged from 18.69±1.991 - 28.581±11.213. The mean total of HMW PAHs ranged from 12.673±5.554 - 20.792±2.437. The sum of eight probable carcinogenic PAHs detected ranged from 8.875±2.725 - 13.573±8.793. The mean dietary exposure to PAH for male adult individuals (90.95 µg/kg bw/day) was less than that of female (100.52 µg/kg bw/day) implying that adult female were more exposed. The margin of exposure, MOE values were greater than 10,000 indicating no health concern for risk management actions. The source determination revealed fuel combustion and petrogenic as PAHs emission sources. The TTEC for the cPAHs of the analyzed grains showed non toxicity of the samples. The PAHs detected in the samples were below 1.0 µg/kg which is the permissible limit established by EFSA and are considered safe for consumption.
Abstract: This study aimed at determining the; quantity of polycyclic aromatic hydrocarbons, PAHs in beans, soyabeans, corn and guinea corn consumed in South East Nigeria; source of emission; daily intake amount and health risks associated with their consumption among adult male and female individuals. Thirty six grain samples from markets in Eastern part of...
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