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On October 2004, a sampling survey was carried out in Florence to estimate urban fine particle exposure concentrations inside commuting vehicles during workdays characterized by heavy traffic. Portable samplers were positioned inside four regularly scheduled diesel-powered buses and four taxis during eight weekdays. Each sampler consisted of a 2.5μm size pre-separator cyclone, a direct-reading data logging photometer (pDR-1200), and a 4Lmin−1 filter sampler for the determination of PM2.5 mass concentration. Based on reflectance analysis measurements, a PM2.5 Black Smoke Index was determined for each filter, and the elemental composition of the PM2.5 was analyzed by Particle Induced X-ray Emission (PIXE). PM2.5 mass concentrations inside the vehicles correlated well with the urban ambient air PM2.5 concentrations measured at the fixed-site monitoring stations. The PM2.5 excess above the urban ambient level was on average 32μgm− 3 (range: 22–52μgm− 3) and 20μgm− 3 (range: 11–29μgm− 3) in buses and taxis, respectively. The PM2.5-bound sulfur concentration was also higher in the buses than in the taxis. Based on daily Time-Microenvironment-Activity-Diary (TMAD) data, the Florentines spend on average 9.7% of their day in traffic, and the corresponding average exposure is approximately 12% of their daily PM2.5 personal exposure. The obtained data could be used to plan interventions to minimize the PM2.5 citizen exposures in commuting. [Copyright &y& Elsevier]

The benzo[ a ]pyrene temporal trend was investigated in 11 towns where at least five annual means were available. The overall number of stations was 22, of which 12 were traffic-oriented, 6 background and 4 industrial. The trend was generally declining at traffic-oriented sites and roughly stable at background sites. The annual means in 2004 still exceeded the forthcoming European target value of 1 ng/m 3 in two towns (up to 1.9 ng/m 3 ). The background means (up to 1.4 ng/m 3 in 2004) accounted for approximately 40–90% of those at the traffic-oriented sites in the same town. The presence of a coke plant was incompatible with the attainment of the target value, while the adoption of technical measures on a carbon electrode plant was successful in attaining concentrations lower than the target value. In heavy traffic areas in Italy, the attainment of the target value hardly appears feasible under the current conditions of traffic congestion. [ABSTRACT FROM AUTHOR]