A mechanical filter-based air pollution control system for removing particle and gas phase pollutants in a waste airstream exhausted from commercial cooking operations is described, which includes a housing enclosing at least three filter stages to remove particle and gas pollutants in the airstream. The example system may include a fogger assembly that sprays fog droplets into the waste airstream to condense a portion of gas phase pollutants into condensed particles, a wash mechanism including spray nozzles to wash surfaces of the first stage filter to remove grease therefrom, and injection means for injecting activated ozone, which comprises ozone with a surplus of hydroxyl radicals, into the housing to initiate advanced oxidation processes (AOPs) to decompose particle and gas phase pollutants within the waste airstream in the filters. Where activated ozone is employed, the system includes a fourth stage filter that adsorbs and retains gas phase pollutants for subsequent oxidation.