The use of Aleppo pine needles as a bio-monitor of heavy metals in the atmosphere.

The needles of Aleppo pine (Pinus halepensis L.) tree were tested as a possible bio-monitor of heavy metal pollution in Amman City, Jordan. Concentrations of Pb, Cd, Cu and Zn were determined in soils, unwashed and washed needles collected from different sites of the city, viz. industrial, residential and on the roadside of a busy high way. The analyte concentrations were compared with that of samples from the control site (uncontaminated area that was 60 km away from Amman City). The results of the investigation indicate that the industrial site has high levels of the metal pollutants except for Pb and Cu which is much higher on samples from the roadside. The highest concentrations were registered for Pb and Zn where 10 and 1210 microgg(-1), respectively, were found in soil, thereby leading into the contamination factor of 13 and 17 as compared with samples from the control site. The results obtained indicate that P. halepensis L. needles are useful bio-monitor of the heavy metals in the arid environment.