The national statistics release that covers UK emissions of:
sulphur dioxide (SO2),
nitrogen oxides (NOx),
non methane volatile organic compounds (NMVOCs),
ammonia (NH3)
and particulate matter (PM10 and PM 2.5).
The National Atmospheric Emissions Inventory: http://naei.defra.gov.uk/ contains further information on air pollutant emissions and methodology http://naei.beis.gov.uk/reports/reports?report_id=946.
The Devolved Administrations’ Air Quality Pollutant Inventories is : NAEI http://naei.defra.gov.uk/reports/reports?report_id=763