An evaluation of the PM_(2.5) trace elemental composition in the Venice Lagoon area and an analysis of the possible sources

摘要

Global emissions reported by many authors have shown as natural and anthropic sources can contribute to the principal aerosol classes, but values change according the local scenario. The Venice Lagoon is exposed to different anthropic source emissions like vehicular traffic, industrial thermoelectric power plant, petrochemical plant, incinerator plant, domestic heating, ship traffic, glass factories and airport. Samplings of PM_(2.5) were daily performed between March and November 2007 in Sacca San Biagio island (Venice), and values of PM_(2.5) concentration and element concentration were obtained. Monthly average concentrations (μg m~(-3)) during this period show higher values during the spring and the autumn. A good relationship between data obtained and concentration values from environmental local agencies is evidenced, both for PM_(2.5) from urban area (Venezia Mestre), and for PM_(10) sampled in the same area, as well as the influence of some meteorological parameters on PM_(2.5) concentration sampled. Trace elements samples were measured by an Inductively Coupled Plasma-Quadrupole Mass Spectrometry (ICP-QMS), and values (ng m~(-3) and μg g~(-1)) for elements regulated by European directives (As, Cd, Ni, Pb), as well as, other elements (Na, Al, K, Ti, V, Mn, Fe, Co, Zn, Se, Ag) are also reported. Data analysis by mean of Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF) pointed out four principal groups of elements like Mn-Fe-K, As-Se-Cd, V-Co, and Pb that could be assigned to specific sources of the Venetian wetland basin.