A vulnerability-based approach to human-mobility reduction for countering COVID-19 transmission in London while considering local air quality

Manu Sasidharan; Ajit Singh; Mehran Eskandari Torbaghan; Ajith Kumar Parlikad

Various studies have reported an association between air pollution levels and excess morbidity and mortality from respiratory diseases [29, 30] . Both long-term and short-term exposure to air pollution has been associated with a variety of respiratory conditions [11] with children and elderly people being at most risk [31] . Our analysis shows that short-term exposure to air pollution (both NO2 and PM2.5) is significantly correlated with an increased risk of contracting and dying from 20 COVID-19. It was reported by [6] that long-term exposure to fine particulate matter (PM2.5) increases the risk of COVID-19 deaths. Biologically, either long-term or short-term exposure to air pollutants such as PM2.5 and NO2 can compromise lung function and therefore increasing the risk of death from COVID-19 [7] . Also, the median level of airborne PM2.5 in LU during summer is often several times higher than other transport environments such as cycling (35 μg m −3 ), bus 25 (30.9 μg m −3 ), cars (23.7 μg m −3 ) [32, 26] . The greatest PM2.5 concentrations across the LU network was reported to be on the Victoria Line (around 16 times higher than roadside environment), followed by Northern, Bakerloo and Piccadily line [26] . The routine cleaning and maintenance of LU ranges from litter removal to preventing safety incidents rather than on reducing PM concentrations. Our study is in agreement with [22] who reported that there are higher 30 pandemic case rates for London boroughs with access to interchange stations, as individuals would interact with more people in comparison to through stations.