Preliminary Investigation of Heavy Metals in Deposited Dust on Roadside Sidr Leaves

Urban pollution has different forms; one of them is air pollution by natural sources such as dust storms or by anthropogenic sources such as traffic, whereas both are considered among the most risky environmental problems especially when it reaches soil surface and is transported to plants and enters food chain. The current study aims to evaluate the heavy metals in dust, deposited on the leaves of the Sidr trees by roadsides as a first step in assessing the use of this plant as a bio-monitor of environmental pollution. The Sidr tree was chosen to evaluate the impact of pollution because it is very common in the region and among evergreen trees in the streets, gardens and residential areas of Doha. The study was carried out close to Qatar University campus in Doha city (traffic intersections and near construction activities) as well as from a farm (located far away from traffic) as a control sample. The concentrations of ten traffic-related metals namely iron (Fe), cadmium (Cd), lead (Pb), copper (Cu), nickel (Ni), zinc (Zn), manganese (Mn), aluminum (Al), barium (Ba), and mercury (Hg) were determined in the deposited dust on leaves using ICP-OES. In our preliminary findings, we found that the distribution of trace metals in leaf dust samples from our study is similar to those reported in an earlier study done in southwestern Iran.