Formation of oxidants other than o3 Formation of aldehydes(e.g. formaldehyde) Formation of pan (peroxyacetyl nitrate)and its analogs C +h +H. H3C H H3C H3C H3C PAN N H3C OONO ROO.+ No2> ROoNO2(peroxyalkyl nitrateFormation of oxidants other than O3 • Formation of aldehydes (e.g. formaldehyde) • Formation of PAN (peroxyacetyl nitrate) and its analogs ROO. + NO2 → ROONO2 (peroxyalkyl nitrate) O C H3C H + hv O C H3C + H O C H3C + O2 O C H3C OO O C H3C OO + NO2 O C H3C OONO2 PAN