In this study, particulate matter (PM) were characterized from a place impacted by heavy-duty vehicles (Bus Station) fuelled with diesel/biodiesel fuel blend (B3) in the city of Londrina, Brazil. Sixteen priority polycyclic aromatic hydrocarbons (PAH) concentrations were analyzed in the samples by their association with atmospheric PM, mass size distributions and major ions (fluorite, chloride, bromide, nitrate, phosphate, sulfate, nitrite, oxalate; fumarate, formate, succinate and acetate; lithium, sodium, potassium, magnesium, calcium and ammonium). Results indicate that major ions represented 21.2% particulate matter mass. Nitrate, sulfate, and ammonium, respectively, presented the highest concentration levels, indicating that biodiesel may also be a significant source for these ions, especially nitrate. Dibenzo[a,h]anthracene and indeno[1,2,3,-cd]pyrene were the main PAH found, and a higher fraction of PAH particles was found in diameters lower than 0.25 μm in Londrina bus station. The fine and ultrafine particles were dominant among the PM evaluated, suggesting that biodiesel decreases the total PAH emission. However, it does also increase the fraction of fine and ultrafine particles when compared to diesel.

The use of biofuels in Brazil is encouraged so it is important to monitor changes in emissions from combustion processes, in air quality and impacts on the environment. Concentrations of phenanthrene in vapor and particulate phases were measured inside a bus station following the changes in the biodiesel/diesel mixtures (B0 to B8) along seven sampling campaigns. Impactors were used for collection of fine particulate material (PM2.5) and for vapor phase, cartridges with resin XAD-4. Phenanthrene was determined by HPLC and fluorimetric detection. Comparing B0 and B8 campaigns, it was observed that phenanthrene concentrations decreased by 93 % in MP2.5 and 42 % in the vapor phase. Despite that decrease, the emissions resulting from the use of diesel/biodiesel blends with the growing addition of biodiesel should continue to be investigated, due to the health risks associated with HPA exposure.