J. Saudi Chem. Soc., Vol. 9, No. 1; pp. 27-36 (2005) 27 A COMPARATIVE ENVIRONMENTAL STUDY ON THE VARIATION OF HEAVY METALS IN SOIL AND PLANTS SPECIES BY FLAME ATOMIC ABSORPTION SPECTROSCOPY Iftikhar Imam Naqvi, M. Farrukh Ahmed and M. Akhyar Farrukh 1 Department of Chemistry, University of Karachi, Karachi-75270, Pakistan 1 Present Address: P.C.S.I.R. Laboratories Complex, Jamrud Road, Peshawar-25120, Pakistan E-mail: akhyar100@yahoo.com (Received 8 th May 2004; Accepted 29 th Dec. 2004) ﻓﻴﻬﺎ ﺍﻟﺜﻘﻴﻠﺔ ﺍﳌﻌﺎﺩﻥ ﻭﺟﻮﺩ ﲢﻠﻴﻞ ﻭﰎ ﻛﺮﺍﺗﺸﻲ ﻣﺪﻳﻨﺔ ﻣﻦ ﻭﻣﻠﻮﺛﺔ ﻧﻈﻴﻔﺔ ﻣﻨﺎﻃﻖ ﻣﻦ ﻟﻠﻄﺮﻕ ﺍﳉﺎﻧﺒﻴﺔ ﺍﻟﻨﺒﺎﺗﺎﺕ ﻣﻦ ﻋﻴﻨﺎﺕ ﺃﺧﺬﺕ. ﻭﺍﻟﺘﺮﺑﺔ ﺍﻟﻨﺒﺎﺗﺎﺕ ﻫﺬﻩ ﺃﻭﺭﺍﻕ ﺃﺧﺬﺕ ﻭﻗﺪ) ﻭﻋﻤﻴﻘﺔ ﺳﻄﺤﻴﺔ( ﺍﻟﺪﺭﺍﺳﺔ ﳍﺬﻩ ﻛﻌﻴﻨﺎﺕ. ﰲ ﺍﻟﺬﺭﻱ ﺍﻻﻣﺘﺼﺎﺹ ﻃﻴﻒ ﺗﻘﻨﻴﺔ ﺗﻄﺒﻴﻖ ﻭﰎ ﺍﻟﺘﺤﻠﻴﻞ ﻫﺬﺍ. ﺍﻟﺮﺻﺎﺹ ﻣﺴﺘﻮﻯ ﺃﻥ ﻭﻭﺟﺪ ﺍﳌﺮﻭﺭ ﻛﺜﺎﻓﺔ ﺫﺍﺕ ﻭﺍﳌﻨﺎﻃﻖ ﺍﻟﺼﻨﺎﻋﻴﺔ ﺍﳌﻨﺎﻃﻖ ﰲ ﻭﺍﻟﺘﺮﺑﺔ ﺍﻷﻭﺭﺍﻕ ﰲ ﻣﺮﺗﻔﻊ ﻭﺍﻟﻨﺤﺎﺱ ﺍﻟﻌﺎﻟﻴﺔ. ﺍﳌﻌﺪﻥ ﺗﺮﻛﻴﺰ ﻋﻠﻰ ﻳﺆﺛﺮ ﺍﳌﻄﺮ ﺃﻥ ﻭﻭﺟﺪ. ﺗﺮﻛﻴﺰ ﻣﺴﺘﻮﻯ ﻳﻘﻞ ﺑﻴﻨﻤﺎ ﻭﺍﻟﻜﻮﺑﺎﻟﺖ ﺍﻟﺮﺻﺎﺹ ﺗﺮﻛﻴﺰ ﻣﺴﺘﻮﻯ ﻳﺰﺩﺍﺩ ﺣﻴﺚ ﺍﳌﻄﺮ ﺑﻌﺪ ﻭﺍﻟﻜﺎﺩﻣﻴﻮﻡ ﺍﻟﻨﻴﻜﻞ ﺍﻟﻨﺤﺎﺱ،. ﺍﻷﻭﺭﺍﻕ ﰲ ﺍﳌﻌﺎﺩﻥ ﻣﺴﺘﻮﻯ ﺃﻥ ﻭﻭﺟﺪ ﺍﻟﺘﺮﺑﺔ ﰲ ﻣﻨﻪ ﺃﻗﻞ. ﰲ ﹰ ﺗﻘﺮﻳﺒﺎ ﻛﺎﻧﺖ ﻓﻘﺪ ﻭﺍﻟﻜﺎﺩﻣﻴﻮﻡ ﻭﺍﻟﻨﻴﻜﻞ ﺍﻟﻜﻮﺑﺎﻟﺖ ﻣﺴﺘﻮﻳﺎﺕ ﺃﻣﺎ ﺍﻟﺘﺮﺑﺔ ﻋﻤﻖ ﻭﰲ ﺳﻄﺢ ﻋﻨﺪ ﺍﳌﺴﺘﻮﻯ ﻧﻔﺲ. ﻋﻨﺪ ﻣﻠﺤﻮﻅ ﺑﺸﻜﻞ ﺃﻋﻠﻰ ﺍﻟﺴﻄﺢ ﻋﻨﺪ ﻭﺍﻟﻨﺤﺎﺱ ﺍﻟﺮﺻﺎﺹ ﳏﺘﻮﻯ ﻛﺎﻥ ﺑﻴﻨﻤﺎ ﺍﻟﻌﻤﻖ ﰲ ﻋﻨﻪ ﺍﻟﺴﻄﺢ. ﻭﺍﳌﺨﻠ ﺍﻟﺴﻴﺎﺭﺍﺕ ﻋﺎﺩﻡ ﺃﻥ ﻋﻠﻴﻬﺎ ﺍﳊﺼﻮﻝ ﰎ ﺍﻟﱵ ﺍﻟﺒﻴﺎﻧﺎﺕ ﻭﺃﻛﺪﺕ ﻟﻠﺘﻠﻮﺙ ﺍﳌﺴﺒﺐ ﻫﻲ ﻛﺮﺍﺗﺸﻲ ﻣﻨﻄﻘﺔ ﳏﻴﻂ ﰲ ﺍﻟﺼﻨﺎﻋﻴﺔ ﻔﺎﺕ. Roadside plants (Eucalyptus and Guaiacum Officinale) from controlled and polluted areas of Karachi city were analyzed for heavy metals. Leaves of these plants and the soil (surface and depth) were taken as samples for this study. Atomic Absorption technique was employed for the analysis. Levels of Pb and Cu were found to be elevated in leaves and soil of industrial and high traffic density areas. Rain was found to influence the metal concentration. Pb and Co levels increased while Cu, Ni and Cd levels got decreased following rain. Levels of metals in leaves were found to be less than that of soil. Levels of Co, Ni, and Cd were found to be almost the same at surface and depth of soil. However the Pb and Cu contents at surface soil were significantly higher than the depth. The collected data manifests that automobile exhaust and industrial wastes in urban areas of Karachi are causes of pollution. Key Words: Heavy metals, plants (Eucalyptus and Guaiacum Officinale), soil, Environment, Flame Atomic Absorption Spectroscopy (FAAS) INTRODUCTION Heavy metals along with other pollutants are discharged into the atmosphere through industrial activities (dye stuffs, pigments, drugs, agro- chemical, plastics, batteries, zinc recovery operations, electroplating and metal surface cleaning agents and discharge of untreated effluents from these industries), automobile exhaust, refuse burning, man made activities, pesticides use in agriculture etc. It has now been well established that aerosol and deposited dusts in urban areas contain substantial amounts of many potentially toxic trace metals in comparison with those found in non-urban areas [1]. Thus, people residing in urban areas are exposed to larger amounts of potentially hazardous elements than their city-counterparts. It has been reported that plants are more sensitive to pollution than animals or man. Injury to vegetation caused by heavy metals has been well documented as a result of many botanical and