Abstract

Introduction: Air pollution is emerging as a crucial risk factor for respiratory health problems like Chronic Obstructive Pulmonary Disease (COPD) and asthma in developing countries, including Nigeria where air pollutant concentrations are elevated. In these countries, urban and peri-urban areas like Abuja bear the bulk of the problem. Nevertheless, data on the health effects of air pollution and pollutants are limited. This study aimed to critically examine the health effects of particulate matter less than 10 μg/m3 (PM10), and nitrogen dioxide (NO2) in Abuja FTC, Nigeria.
Methodology: The diurnal effect of PM10, and NO2 concentrations was used to examine COPD and asthma patients due to exposure to these pollutants from November 2015 to December 2018. PM10 and NO2  air concentrations were monitored by the Nigerian Metrological Agency throughout the study. The 402 participants recruited were part of a major study which examined the effect of photochemical smog on COPD and asthma patients. For this study, participants completed the Medical Research Council (MRC) dyspnoea questionnaire; lung function tests was performed to determine the airway obstructive level in association with the pollutant at varying concentrations.
Results: The 24-hour mean of PM10 was 296.7µg/m3, and the NO2 1-hour mean was 253.1µg/m3, which are both higher than the WHO set thresholds. The diurnal variation of PM10 varied from an average of 149.5µg/m3 in the morning to 345.3µg/m3 during the afternoon (dry season) and 108.5µg/m3 to 250.4µg/m3 (wet season). The PM10 increase was significantly associated with decreased forced expiration volume (FEV)1 and forced vital capacity (FVC) in the participants (-786, P=.000); with a moderate significant association between NOx and FVC (-.582, P= .018). A significant association was also observed between PM10 with Dyspnoea (-.786, P=.000). When we stratified for gender, it was observed that women had a higher significance P=.001 and for every 10 μg/m3 increase in NO2 and PM10 concentration above the WHO recommended 24hr thresholds, the relative risk for developing respiratory symptoms was 1.09 (95% CI: 1.07 to 1.05) and 1.06 (95% CI: 1.01 to 1.10), respectively.
Conclusion/Recommendation: There is high level of pollutant concentration with strong association with COPD and asthma symptoms in FCT Abuja. Immediate policies and actions are needed to reduce pollutants from various sources including from transport and energy manufacturing facilities.