The concentration of a number of trace elements (Cr, Mn, Fe, Co, Ni, CU, Zn, Ga, As, and Pb) in submicrometer aerosols generated in the combustion of a biomass in an entrained flow reactor has been determined in a wide range of realistic combustion conditions (which included variations in temperature and concentration of O-2 and SO2 in combustion gases). Fine particles were enriched in most of these elements with respect to the bulk fly ash; the fraction of each one found in fines is ascribed to vaporization and subsequent condensation. Their concentrations increased with the combustion temperature, were little affected by the SO2 concentration (except for Fe) or the major composition of fine particles, and displayed element-dependent behaviors when the oxygen concentration was varied. Also, the sequential condensation of trace elements was experimentally studied at moderate temperatures (900-560 degrees C); Ph was found to condense in this temperature range, whereas CU remained partly as vapor still at 560 degrees C.