BACKGROUND Biofiltration of methane is of particular interest to contribute to limiting the greenhouse gas effect of biogas emissions from landfills. The complexity of the biogas mixture from landfills has underlined the importance of the presence of non-methane organic compounds. The aim of this study was to determine the effect of toluene on the microkinetic and macrokinetic parameters of methane biodegradation using an inorganic filter bed. RESULTS Two concentrations of toluene were tested, 0.7 and 3.4 gC m(-3), and compared with the case of methane biofiltration alone. The specific growth rates of methane decreased from 0.793 to 0.574 to 0.278 d(-1) when the toluene concentration was increased from 0 to 0.7 to 3.4 gC m(-3), respectively. The maximum elimination capacity of methane decreased from 39.4 to 5.6 gC m(-3) h(-1) when toluene concentration was increased from 0 to 3.4 gC m(-3). The half-saturation constants decreased from 4.6 to 1.6 gC m(-3) and from 4.6 to 0.7 gC m(-3), respectively. CONCLUSIONS Results show that an inhibition occurred on methane biodegradation when toluene was introduced into the biofilter. (c) 2013 Society of Chemical Industry