The Assessment of Atmospheric Pollution of Heavy Metals with the Help of Ornamental Plants in Isfahan Landscape

Plants are the most common bioindicatorsused in air quality biomonitoringstudies because they are immobile and they have more sensitive to the mostprevalent air pollutants than humans and animals. to identify the concentrationsand sources of heavy metals in ornamental plants of isfahan landscape,samples of leaves and soil around pinuseldarica and nerium oleander werecollected at different distances (1, 4 and 10 km) from the most populated anddense vehicle traffic area of isfahan and control site with and opposite winddirections (sw and ne).for determination of heavy metal contaminationsource, plant leaves were washed with distilled water. finally, concentrationsof zinc, lead and cadmium in soil and plant samples were determined byatomic absorption. heavy metals were found at higher concentrations in the allstudied sites in comparison with control. heavy metal concentrations were increasedwith reducing distance from contamination center with wind direction.negligiblecorrelation between plant available zn and pb concentrations in soiland metal contents in plant leaves and reduction of these metals by waterwashing treatment indicated that soil cannot be the source of metal contaminationin plants. both ornamental plants were found to be appropriate indicators forairborne zn and pb contamination, especially nerium oleander.