Two types of biomass fuel were gasified in a steam atmosphere using a bench-scale fluidized bed reactor. Filter char, bed material and the product gas stream were sampled and analyzed for a total of 21 elements including Al, Ca, Fe, K, Mg, Na and Si defined as major elements (ME), and Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, P, Sr, Pb, Ti, V, and Zn defined as trace elements (TE). The effects of the sampling system and gasification system on the measurement were determined. Mass balances for ME and TE are reported for individual elements and overall. It was found that most ash particles or metal elements can be captured by a silicon carbide candle filter that removes small particles from the gas phase, but some of volatile elements pass through the filter and are present in the gas stream. (C) 2011 Elsevier Ltd. All rights reserved.