A method and apparatus are provided for improving the efficiency of an aqueous froth filter. An array of saturated mesh assemblies interacts with an incoming contaminated air stream. As the air stream flows through the saturated mesh assemblies, an aqueous froth is generated immediately downstream of each mesh assembly. As the bubbles of the froth move downstream towards the next saturated mesh assembly, the velocity of the air stream causes at least some of the bubbles to burst. The bursting bubbles rupture into hundreds or thousands of micro-droplets. The micro-droplets are used together with the aqueous froth to coalesce with or otherwise bind with contaminants in the air stream. An optional feature is that massive particles greater than three microns in diameter are removed by inertial impaction, whereby those heavy particles collide with the walls of serpentine shaped vanes of a mist eliminator. The method and apparatus are capable of filtering chemical and biological warfare agents out of an air stream. The invention is also useful in removing contaminants from industrial air streams.