Gasoline light-duty vehicles were the main emitters of CO and NMVOC, accounting for 85% and 65% of emissions respectively, while they only represented a small fraction (w20%) of CH
2
4
,N
2
2
4
O, NO
emissions. Together, diesel light and heavy-duty vehicles were responsible for almost all PM emissions, 80% of SO
emissions and 55% of NO
x
2
emissions, while they accounted for only 4% of CO
2
x
and N
x
2
and SO
2
4
2