Passenger cars emit exhaust emissions of regulated pollutants (CO, HC, NOx in the case of gasoline engines and also particulate matter (PM) in the case of diesel engines); however, they also emit several other pollutants which are not regulated (non-regulated pollutants, NRP). These pollutants are emitted in much lower concentrations than the regulated ones; however, they are sometimes much more dangerous for the environment and the human health. This work shows the emissions of several non-regulated pollutants of gasoline and diesel European passenger cars tested on the New European Driving Cycle. The pollutants studied in this work are individual HC and HC families, N₂O and NH₃, carbonyl compounds, PAH and nitro-PAH. The impact of emission technology from Euro1 to Tax Incentives Euro4, which are related with the emission level of regulated pollutants, and of mileage are presented and discussed.