Toxicologia Ambiental e Analítica

Phylloremediation of Polyaromatic Hydrocarbonic Pollutants Using Phylloshere Bacteria

Abstract

Undugoda LJS, Nilmini AHL and Nugara NNRN

Polyaromatic air pollution is a serious environmental issue in the modern world due to the high carcinogenicity and geno-toxicity of these pollutants to the all-living beings. These pollutant concentrations in the air are being increased day by day due to huge vehicular emissions, oil refining processes and other industrial processes spread among urbanized areas. Gas or particle bounded PAHs in the air deposit on ground level through wet deposition or dry deposition. These pollutants deposition mainly on plants other than many exposing surfaces spread among the earth. Therefore, the plant leaves highly abundant in urban areas rich with these deposited pollutants. All plant leaves are great niches for microorganisms which is called phyllosphere. Phyllosphere of plants consists with many phyllosphere microorganisms belong to different group of bacteria, fungi, algea and protozoa. Among them bacteria are the predominant phyllosphere microorganisms. The phyllosphere bacteria highly abundant in polluted areas have special capability to degrade polyaromatic hydrocarbons. These PAH degrading phyllophere microorganisms can be used to clean the polluted air, this is called phylloremediation. Phylloremediation is an effective bioremediation method which can use to remediate the air, water and soil polluted from the PAH compounds. The aim of this review is to discuss polyaromatic hydrocarbonic air pollution and deposition of these chemicals on phyllosphere. High depositions of PAHs on plant leaves created harsh conditions to the inhabiting bacterial population in this phyllosphere and their ability to degrade PAH compounds are discussed. Then possibilities of usage of phylloremediation to clean the polluted air from the PAH compounds are discussed.