Particle-phase polycyclic aromatic hydrocarbon emissions from non-catalysed, in-use four-stroke scooters.

The emissions of particle-phase polycyclic aromatic hydrocarbons (PAHs) were evaluated in the exhaust of four (two EURO-0 and two EURO-1) four-stroke engine, in-use scooters with displacement of 150 cc, which were not equipped with catalytic converters. Non-catalysed motorcycles still represent a large proportion of circulating two-wheelers in Italy and, possibly, also in other countries. Tests were performed on a dynamometer bench, using the ECE-40 test cycle procedure.