A comparison of the mineralization of xenobiotic compounds in uncontaminated and contaminated soils

grantor: University of TorontoSoils from various locations in Ontario, Canada, were taken and tested for their ability to mineralize several chlorinated aromatic compounds. Samples were taken from three forests and two agricultural fields. The compounds tested are pentachlorophenol, 2,4-dichlorophenol, 4-chlorophenol, 3-chlorobenzoate, 2,4-dichlorophenoxyacetate and atrazine. Results reveal that the ability to mineralize chlorinated organic compounds is commonly found in soils without previous direct exposure to xenobiotics. Natural compounds that are analogs of xenobiotics may explain why microorganisms can quickly mineralize them. 3-Chlorobenzoate and 2,4-dichlorophenol, appear to resemble natural compounds in forest soils to a greater extent than the other compounds, since the former are mineralized better in forest soils than in agricultural soils. The 2,4D degraders in the forest soils may belong to a recently isolated group of slow growing degraders ($\alpha$-Proteobacteria) that mineralize 2,4-dichlorophenoxyacetate via an unknown pathway.M.Sc