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An industrially polluted soil (3.1gPAHkg⁻¹) was used to study C, N and P limitations to dissipation of polycyclic aromatic hydrocarbons (PAHs) in a model rhizosphere. Soil columns (50cm³) were packed with soil and percolated daily with artificial root exudates (ARE) at 100μgCg⁻¹, 1mM NH₄NO₃ or 1mM NaH₂PO₄, or any double or triple combination of these for 30 days. At harvest, soil was analyzed for PAHs, and the numbers of total heterotrophic and PAH degrading bacteria estimated by an MPN technique. Dissipation of 3 and 4 ring PAHs was highest in soil receiving ARE+N, followed by the treatments with N+P and ARE+N+P. The complete treatment ARE+N+P had the highest dissipation of 5-ring PAHs. For both 5 and 6 ring PAHs most treatments resulted in increased concentrations at the end of the experiment, which was attributed to desorption of initially unextractable molecules. PAH degrading bacteria …