ASSESSMENT OF SEASONAL VARIATION OF AMBIENT AIR POLLUTANT CONCENTRATIONS AROUND SLUM SETTLEMENTS IN LAGOS METROPOLIS, NIGERIA
Keywords:Assessment, seasonal variation, air pollutant, slum settlements, meteorology
This study assessed the effect of seasonal variations on the air quality around slum settlements within Lagos Metropolis. Air parameters were monitored from different slums around the settlement of Majidun (Group A), Oworoshoki (Group B), Bariga (Group C), Iwaya (Group D) and Ijora Badia (Group E) for wet and dry seasons from 2018 to 2019. Parameters analysed are volatile organic compounds (VOC), carbon dioxide (CO2), nitrogen dioxide (NO2) and sulphur dioxide (SO2) using Aeroqual gas monitor. The data obtained were analysed using statistical package for social sciences (SPSS) for Windows. The result of the analyses showed that all the parameters have higher concentration during the dry season than in the wet season across the Groups, except VOC. Pressure and relative humidity have higher concentration during wet season than dry season among the groups.
Paired sample t-test results revealed that VOC, CO2, NO2 and SO2 showed no significant variation in all Groups. Pressure and relative humidity had significant variation across the groups. Most of the parameters have their mean values within the WHO standards in both seasons. Mean values for NO2 and SO2 are higher than the guideline provisions. Results of principal component analysis (PCA) revealed that CO2 contributed a strong positive loading across the groups except for Group C, while
VOC had a strong positive loading in Group C and D during wet season. Temperature and relative humidity (RH) contributed to a strong positive loading across the Groups except for Group C during wet season. CO2 and VOC have a strong positive loading across the Groups except for Group E and B during dry season. More so, temperature and pressure exhibited a strong positive loading across the Groups except for Group A, C, and E respectively. The study concludes that seasons significantly influence the concentration of pollutants in the slums. Therefore, the need for monitoring and enforcement of appropriate laws should be considered in the slum settlement to reduce the risks associated with these pollutants.