Comparative assessment of air quality in Epe, and Olusosun dumpsites of Nigeria

Abstract

ABSTRACT

A comparative assessment of air quality in Epe and Olusosun dumpsites was carried out with a view to understanding if the historical background of dumpsites had an influence on their perceived impacts on the environment as well as their emission concentrates. Primary data was collected through questionnaire administration and the use of portable emission monitoring instruments. A total of 120 copies of self-designed interview questions were administered for the study but 116 were retrieved from both dumpsites and considered valid for the analysis. On the other hand, data collection with a portable air quality monitor was carried out during the month of October 2022. Sampling was done between 10 am and 1 pm. A 60-minute exposure time was observed with each of the instruments (AEROQUAL 500 Series) to measure Carbon dioxide (CO₂), Methane (CH₄), Oxides of nitrogen (NO_x), Sulfur dioxide (SO₂) and Carbon monoxide (CO) and sizes of suspended particulate matter (PM_2.5 and PM_10.0) were measured using handheld particulate matter monitoring equipment (AEROCET 531S by Met One Instruments). Within this time belt, the readings were taken three (3) times and averaged to get a value for the time belt using descriptive statistics. The result indicated high concentrations of CO₂, CH₄ and PM during the early hours of the day and gradually decreased as the day went by at both dumpsites. The concentration of SO₂ was higher at Olusosun dumpsite on day 5 when temperature and relative humidity were high from 12 noon. NO_x was detected at both dumpsites at a minimal concentration. In conclusion, higher concentration levels recorded in all analysed gas samples collected from the Olusosun upland dumpsite suggested that the only historical component that could have influenced the dumpsite was “the age of dumpsite” since it is way older than the Epe wetland dumpsite. The topographical nature of the dumpsites (upland and wetland) appears not to have an impact on the air quality values measured. The perception of residents in both dumpsites showed that they were concerned about living and carrying out daily operations in and around the dumpsites.