To investigate metal biosorption in polluted environments where organic and inorganic pollutants coexisted, this study has focused on the removal of Cu(NO3)(2) by Stenotrophomonas maltophilia in the presence of benzo[a]pyrene (BaP). Initial pH, biosorbent dosage, contact time and BaP concentration were the significant factors for Cu biosorption. The uptake capacities of 2 and 10 mg L-1 Cu(II) by 0.25 g L-1 S. maltophilia were 7 and 26 mg g(-1) at 0.5 h, respectively. Cu(II) biosorption included bioaccumulation, ions and macromolecules release, Ca2+ and Mg2+ exchange, functional groups attraction, and Cu(II) and NO3- bio-reduction. During the biosorption process, S. maltophilia metabolically released K+, and metabolically independently exchanged Mg2+ and Ca2+ for Cu(II) bioaccumulation. When the initial concentration of Cu(II) was 2 or 10 mg L-1, the coexisted 1 mg L-1 BaP showed no significant influence on Cu(II) biosorption, ions release and cellular morphology. (C) 2013 Elsevier B.V. All rights reserved.