Abstract
The objective of the present study is the assessment of Jeddah ambient air quality in terms of PM2.5, and the associated lead 7 years after phasing out leaded gasoline in Saudi Arabia. Twenty-four air samples were collected at four locations throughout Jeddah during the period from December 23, 2008 to April 6, 2009. The collected PM2.5-samples were analyzed by ICP-MS for determination of lead. The average atmospheric PM2.5 concentration was 50.8 mu g/m(3). Atmospheric PM2.5-concentrations were higher than the 24-h U.S. National Ambient Air Quality Standards (NAAQS) in 14 sample events. The average lead concentration for all samples was 0.07326 mu g/m(3). Atmospheric lead concentration was dependent on the sampling location. Concentrations at the two southern locations were higher than at the two northern locations. Southern locations had higher lead concentrations due to very high traffic density, in addition to their proximity to industrial zone. In general, the results of this study show a considerable decrease in atmospheric lead concentration 7 years after phasing out leaded gasoline. The study recommends further studies to accurately determine the current sources of atmospheric lead.