Volume 11, No. 6, November 2011, Pages 689-695 PDF(698 KB)
Exposure to PM10, PM2.5, PM1 and Carbon Monoxide on Roads in Lahore, Pakistan
Ian Colbeck, Zaheer Ahmad Nasir, Shakil Ahmad, Zulfiqar Ali
1 Department of Biological Sciences, University of Essex, Colchester, CO4 3SQ, U K
2 Institute of Plant Pathology, University of the Punjab, Lahore, Pakistan
3 Department of Wildlife and Ecology, University of Veterinary and Animal Sciences Lahore
Particulate matter pollution is one of the major environmental concerns in Pakistan. Over the past 20 years there has been a considerable increase in the number of motor vehicles. The present study was conducted to assess journey time and roadside exposure to particulate matter and carbon monoxide along major roads of Lahore during November, 2007. Measurements of particulate mass and carbon monoxide were carried out continuously inside an air conditioned vehicle, while commuting, and outside the vehicle at 36 different locations in the city. Additionally, monitoring was undertaken at a background site throughout the period. The overall mean journey-time concentrations of PM10, PM2.5, PM1, PM10–2.5 and CO were 103 μg/m3, 50 μg/m3, 38 μg/m3, 53 μg/m3 and 8 ppm, respectively. At the roadside average PM10, PM2.5, PM1, PM10–2.5 and CO concentrations were 489 μg/m3, 91 μg/m3, 52 μg/m3, 397 μg/m3 and 4 ppm, respectively. The highest levels were found at the sites with traffic congestion reflecting, not only, the large contribution of automobile exhaust but also the resuspension of road dust. The majority of public transport vehicles in Lahore are not air-conditioned and it is very likely that commuters are exposed to the similar high levels of pollution.
Pakistan; Particulate matter; Carbon monoxide; Exposure; Air pollution.