Environmental impact of biomass burning for civil uses onto a mountain area

The impact of biofuel combustion for civil uses onto the environment was investigated through determining a list of air toxicants at Leonessa, a town lying in Apennines mountain region, Central Italy, and in its surroundings (Terzone). Attention was focussed on suspended particulate matter (PM10), polycyclic aromatic hydrocarbons (PAHs) and regulated pollutants (nitrogen dioxide, ozone and benzene).Two in-field campaigns, each lasting two weeks, were carried out in summer 2012 and winter 2013. Contemporarily, air was monitored in downtown Rome and in other localities of the province. In the summer all pollutants were more abundant in Rome (e.g., PAHs, 0.93 ng/m3, vs. 0.37 ng/m3 at Leonessa and 0.14 ng/m3 at Terzone; benzene, 0.9 µg/m3 in Rome vs. 0.2 µg/m3 at Leonessa), apart from ozone (73 µg/m3 in Rome and >100 µg/m3 at Leonessa). By contrast, in the winter PAHs were more at Leonessa (15.8 ng/m3) than in the capital city (7.0 ng/m3), and benzene was similar (2.3 µg/m3), despite suspended particulates were less (22 vs. 34 µg/m3). Due to lack of other important sources and the scarce impact of transport at mid (inter-regional) scale, biomass burning was identified as the major emitter of PAHs at Leonessa during the winter. Its importance was confirmed by the molecular signatures, pictured by PAH concentration ratios distinct from those of Rome. Other towns too experienced PM levels similar to capital city but higher PAH loads (~9.6 ng/m3), suggesting that uncontrolled biomass burning contributed to pollution across the Rome province. Important differences among PAH diagnostic ratios were observed at the sites also in the summer; nevertheless, in this case the ageing of air masses could play a role. As results of the two in filed compaign can be concluded that biomass burning was the major emitter of PAHs at Leonessa during the winter. In summer period important differences among PAH diagnostic ratios were observed. Despite, the suspended particulates were less than in Rome suggesting the lack of other important sources and the scarce impact of transport at mid scale.