¿The Lombardy Region (RL) is located in the Po Valley and with its more than 9 million residents
it is Italy¿s most densely inhabited area and one of the most polluted areas in Europe with regard to PM and photochemical smog. The EU air quality limit for PM10 of 50 µg m-3 (24 hours average) is exceeded up to 180 days per year and the limit of 40 µg m-3 (yearly average) is in breach for most urban / urban-background areas. In many cities in the new EU member-states,
where coal combustion is a major energy source, such as Krakow, the situation is similar or even
worse. With the aim of identifying efficient abatement strategies for the Lombardy Region, Italy
the EU Joint Research Centre has embarked on a major integrated air quality project focused on
particulate matter pollution to be carried out over a 5 years period (2006-2010). An overview is
given of the results obtained in the first phase of the project and comparisons are made to a recent
project carried out during winter 2005 in Krakow, Poland.
In total 700 (RL) + 150 (Krakow) PM10 samples were collected and analyzed chemically for
the regulated air toxics and source marker compounds including PAHs, higher linear alkanes,
levoglucosan, K and Rb (wood combustion); Ca, Al, Fe, Mg, K, Ti, Ce, and Sr (soil/dust re-
suspension); Na (road salt); Fe, Cu, Sn, Sb, and Mo (break-ware); V(fuel oil); Ce, Rh, Pt, and Pd
(vehicle exhaust catalysts); Zn (tire-ware/tire combustion); Fe, Mn, Cr (railroad steel abrasion). In
order to complete the chemical characterization the most significant cations and anions were also
determined. Quantitative source apportionment was achieved by positive/constrained matrix
factorization (PMF/CMF) and chemical mass balance modeling (CMB).
During the studied pollution episodes in Krakow (Jan.-Feb. 2005) the European air quality
limits were exceeded with up to a factor 8 for PM10 and up to a factor 200 for B(a)P, which is
typical during winter for regions like Krakow. The major culprit for the extreme pollution levels
resulted from CMB and CMF calculations to be residential heating by coal combustion in small
stoves and boilers (>50% for PM10 and >90% B(a)P), whereas road transport (<10% for PM10
and <3% for B(a)P), and industry (4-15% for PM10 and <6% for B(a)P) played a lesser role. The
inorganic secondary aerosol component of PM10 amounted to around 30%, which for a large part
may be attributed to the industrial emission of the precursors SO2 and NOX.
During the Lombardy Region study period (Feb. 2007), the PM10 concentrations were in the range of 21 to 209 µg m-3 and displayed a high degree of synchronism caused by typical winter
meteorological conditions with very weak, cyclic winds, temperature inversions and shallow
mixed boundary layers. The EU 24h limit was exceeded in the vast majority of days all over the
region. The associated air toxics B(a)P, Pb, Ni, Cd and As did not exceed their respective EU
limits with the exception of B(a)P in Sondrio. The secondary aerosol components NH4NO3 and
(NH4)2SO4 contributed with 30-45% of the mass and it is evident that abatement strategies in RL
for PM10 must include the reduction of emissions of gaseous precursors. At all sites, vehicle
emissions and the related re-suspension of road-dust/soil were the main contributors, amounting
to 31-41% of the total PM10 mass. Wood-burning was estimated by CMB with rater high
uncertainties. It contributed with 10-18% of the total PM10 mass in the Po valley and with 27% in
Sondrio (situated in the Valtelline valley). Minor specific sources were revealed for Sondrio
(combustion of fuel oil, 7%), Brescia (cement production, 3%) and sodium chloride was found to
contribute with around 2%, which may derive form long-transported sea-salt, or more likely may
derive from road de-freezing agents.
LARSEN Bo;
JIMENEZ MINGO Jose;
2009-10-15
Istanbul Technical University
JRC50469
https://publications.jrc.ec.europa.eu/repository/handle/JRC50469,
