Abstract
"Air pollution causes 65,000 premature deaths across the Middle East and North Africa every year, where 99% of the population is exposed to pollution that exceeds World Health Organization standards. Nevertheless, studies on the issue are limited. Greater Cairo is the largest megacity in the region where commuters are exposed to excessive pollution. Based on reviewing the literature, conducting field campaigns and emission modelling, this thesis focuses on Greater Cairo on-road transport with the aim to (i) understand car users’ exposure to particulate matter (PM10 with aerodynamic diameter ≤10 µm and PM2.5 ≤2.5 µm) and gaseous pollutants under different car settings, (ii) compare PM2.5 exposure in car, microbus, cycling and walking commutes, (iii) assess five transport emission control scenarios against a ‘do nothing’ scenario for 2030, and finally (iv) estimate the corresponding health burden and economic losses associated with exposure to PM2.5 during commutes.
This thesis includes two field campaigns where personal exposure air quality data were collected using portable monitors during daily commutes. Emission modelling was also carried out to evaluate mitigation measures. Collected data were analysed to understand concentration variations, spatial variability and hot spots, PM2.5/PM10 ratios, exposure doses, commuting costs, assess control scenarios and estimate health burden and economic losses. Several significant findings were noted from the analysis: (i) the choice of car setting affects exposure levels where windows-open resulted in 48% higher PM2.5 concentrations compared to recirculation and AC, (ii) pedestrians and cyclists were exposed to 3.1-times PM2.5 levels of car users with recirculation and AC, (iii) in terms of emission control measures, inspection and maintenance programs proved most effective in reducing health-damaging pollutants while public transport reduced overall emissions and improved the quality of life, (iv) deaths in the microbus population contributed to 57% of the economic losses due to PM2.5 amongst the four modes."