Many types of non-thermal plasma processes have been investigated for environmental applications. The potential of these devices for the destruction of pollutants or toxic molecules has already been demonstrated on NOx and SOx, Volatile Organic Compounds, PAHs in both industrial and engine flue gas. New environmental regulations have been recently issued through European directives. These regulations reinforce constraints and controls for industrial plants especially for gaseous emissions. The understanding of the influence of the various process parameters on the pollutants removal needs to be validated through the chemical balance and the identification of toxic minor components. This approach is essential for predicting the scaling of the process to commercial size units.