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Campioni di particolato atmosferico in dodici diverse classi dimensionali sono stati raccolti nel periodo agosto-novembre 2018 a Sacca Fisola (Venezia), utilizzando un impattore multistadio MOUDI 110. Dopo la pesata, ciascun filtro è stato suddiviso in porzioni, che sono state trattate ed analizzate separatamente. Gli ioni maggiori ed alcuni acidi carbossilici sono stati analizzati in IC- MS dopo estrazione con ultrasuoni in acqua ultrapura; per l'analisi dei metalli le porzioni di filtro sono state digerite in microonde ed analizzate in ICP-MS; la frazione di carbonio organico ed elementare è state quantificata con metodo termo-ottico usando un Sunset analyser. Dalle analisi effettuate sono state ottenute le distribuzioni dimensionali sia della concentrazione di particolato che di tutte le specie selezionate. Il confronto tra le distribuzioni dimensionali, il calcolo di coefficienti diagnostici e l'applicazione di specifiche equazioni ha permesso di effettuare delle valutazioni sulle sorgenti presenti nella zona ed in particolare sull'impatto delle sorgenti nelle diverse classi dimensionali. E' stato infine applicato il modello a recettore Positive Matrix Factorization (PMF5) per ottenere informazioni sui contributi size-resolved delle sorgenti.

Il particolato atmosferico (PM) è un inquinante noto per i suoi effetti negativi sia sull'ambiente che sulla salute umana a causa di esposizione in ambienti indoor e di esposizione outdoor, ed è pertanto oggetto di numerosi studi scientifici. Seppure gli effetti tossici del PM siano stati correlati ad alcune sue proprietà chimico-fisiche, i meccanismi di tossicità non sono ancora del tutto noti. Numerosi studi hanno suggerito che alcuni effetti negativi sulla salute sono riconducibili al potenziale ossidativo (OP) del particolato, che porta ad elevate concentrazioni di Reactive Oxygen Species (ROS), specie chimiche in grado di provocare danni a livello cellulare. Per questo motivo, nella comunità scientifica internazionale, il potenziale ossidativo (OP) del particolato atmosferico è considerato come un potenziale indicatore di rischio per la salute umana. Il contributo al potenziale ossidativo di sorgenti antropogeniche specifiche, come il traffico stradale, la combustione di biomasse e le emissioni industriali, è stato studiato in diversi siti di misura. Tuttavia, le informazioni relative al OP di sorgenti naturali sono scarse e non sono, ad esempio, disponibili dati relativi all'influenza del trasporto transfrontaliero di polveri del Sahara (Saharan Dust Outbreak, SDO) al potenziale ossidativo. Pertanto, è stato condotto uno studio sul potenziale ossidativo di due frazioni dimensionali (PM2.5 e PM10) del particolato atmosferico raccolto presso l'Osservatorio Climatico-Ambientale di ISAC-CNR di Lecce, stazione regionale della Global Atmosphere Watch (GAW).

Le polveri in sospensione in atmosfera (particolato atmosferico) hanno effetti dannosi per la salute umana. I limiti normativi riguardano la concentrazione di polveri in atmosfera, tuttavia, i meccanismi che portano alla tossicità non sono ancora del tutto compresi e la concentrazione non è un indicatore diretto della tossicità. Per questo motivo, nella comunità scientifica internazionale, il potenziale ossidativo è sempre più studiato come un possibile indicatore di rischio per gli effetti dannosi causati a livello cellulare dal particolato atmosferico. Un gruppo di ricerca dell'Istituto di scienze dell'atmosfera e del clima (Isac) del Cnr di Lecce ha condotto uno studio, in collaborazione con l'Università del Salento, che evidenzia come il potenziale ossidativo vari a seconda della composizione chimico-fisica e delle sorgenti del particolato stesso: la tossicità per la salute umana dipenderebbe sensibilmente, quindi, dalla 'qualità' del particolato. Il potenziale ossidativo sarebbe, pertanto, un importante parametro da considerare negli studi epidemiologici sugli effetti dell'esposizione umana al particolato atmosferico.

Studio sulla qualità dell'aria negli ambienti interni, con particolare riferimento al particolato aerodisperso. Sono state effettuate campagne di misura sperimentali in ambienti confinati di diverso tipo (stazioni e convogli della metropolitana, scuole, abitazioni) e di diversa localizzazione geografica (città di Roma e zone semi-rurali circostanti, città di Gela), in diversi periodi dell'anno. Valutazione della concentrazione di massa, della composizione chimica delle polveri campionate e del contributo delle diverse sorgenti nelle diverse condizioni ambientali per la stima dell' impatto sulla salute.

The composition of airborne particulate matter in Montelupo Fiorentino (a small town about 20 km west of Florence characterized by the presence of a large number of ceramic and glass factories) was studied by means of continuous and sequential sampling, ion beam analysis (IBA) techniques and statistical methods. The aerosol PM 10 fraction was collected on a daily basis for about 9 months (September 2002-June 2003). To investigate the elemental size distribution, for a shorter period (about 3 weeks) we collected PM 10 , PM 25 and PM 1 simultaneously. A continuous streaker sampler was also used, which allows the study of the aerosol composition with 2 h time resolution. Mass concentrations were obtained using an analytical balance. The elemental analysis was performed at the INFN accelerator laboratory at the Physics Department of Florence University by particle-induced x-ray emission and particle elastic scattering analysis (the latter implemented for this campaign). The use of the two techniques allowed a complete reconstruction of the gravimetric mass. An absolute principal component analysis showed industrial sources to be, on average, the main contributors to PM 10 mass; however, the weight of the 'soil' source (connected to local soil re-suspension and to long-range Saharan transport episodes) becomes dominant during some of the days when the 50 μg m -3 limit is exceeded.

Sono presentati i risultati di una attività di campionamento e misura della concentrazione di 210Pb in aria tramite analisi spettrometrica gamma di campioni di particolato atmosferico raccolto con un aspiratore di elevato volume, senza ricorrere a metodiche di separazione fisico-chimico di difficile realizzazione. I risultati sono messi in correlazione con alcuni parametri meteorologici, potendo determinare una debole correlazione con la temperatura, la quantità di precipitazione su base mensile e con la direzione del vento più che con la sua intensità.

Psychotropic substances in the atmosphere were monitored in Italy in the frame of the Ariadrugs and PSALM Projects, both aimed at assessing their behavior with regards to spatial and temporal modulations. Average yearly concentrations ranged from 0.02 ± 0.01 to 0.26 ± 0.11 ng m-3 for cocaine, from 0.05 ± 0.05 to 0.96 ± 1.37 ng m-3 for cannabinoids, from 16 ± 6 to 61 ± 28 ng m-3 for nicotine, and from 1.0 ± 0.8 to 8 ± 7 ng m-3 for caffeine. Palermo and Turin were the cities suffering the lowest and the highest psychotropic substance concentrations, respectively. Levels of atmospheric drugs appeared depending on the abuse prevalence in each city. Thus, correlations between drugs and recognized pollutants were checked to identify tools eventually suitable for normalizing the drug concentrations with respect to atmospheric variables. Among all of the chemicals investigated nicotine looked as the best reference substance to normalize neat concentrations of cocaine with regards to the environmental contour where it is dispersed. Dipartimento delle Politiche antidroga della Presidenza del Consiglio dei Ministri

In letteratura sono relativamente pochi gli studi di Source Apportionment (SA) caratterizzati da una dettagliata risoluzione granulometrica del particolato atmosferico [1, 2]. Obiettivo di questo lavoro è stato condurre uno studio di SA su campioni di aerosol raccolti in modalità size-segregated, utilizzando un impattore a 10 stadi (MOUDI II, 120R, intervallo dimensionale tra 0.056 μm e 10 μm), posizionato in un sito di fondo urbano a Lecce.

In recent years there has been increasing interest in the public and in the authorities on properties and origin of atmospheric particulate matter (PM) because of it has been established its negative influence on environment and human health¹. In particular, it is becoming more important to understand the mechanisms that lead to the formation and distribution of atmospheric aerosol. It is a critical problem for analytical chemistry, because the particles consists of more than thousands of substances, both organic and inorganic, so it has not yet been realized a total speciation². Moreover, the processes of atmospheric transport of air masses and the transformation of compounds, which are subjected to oxidizing agents and chemical reactions, make it essential to identify the sources even when they are very distant from the point of collection of PM. For this reason, rather than characterizing all the substances, the modern approaches tend to identify specific substances (markers) that are characteristic of specific sources, in order to distinguish between biogenic and anthropogenic sources and estimate the oxidation level of the substances produced from primary sources (SOA: Secondary Organic Aerosol)³-⁵. The aim of this work was to develop an innovative multi-residue method for the analysis of a complex system like the atmospheric aerosol in order to obtain information about the sources, the anthropogenic contribution and the oxidation level (SOA), identifying and quantifying a wide range of compounds. This work had focused on a group of substances present in the PM that could provide relevant information: the soluble organic fraction (WSOC) in PM, that is the most bioavailable, may be useful in order to estimate the risk on human health. The main components of this fraction are the dicarboxylic acids and sugars³, ⁶. These compounds are present at very low concentrations (average few ng/m3 of air sampled), for this reason there is critical need for efficient and sensitive analytical techniques; gas chromatography coupled with mass spectrometry (GC-MS) is the mostly used because of its great sensitivity and excellent separation and identification capabilities on highly complex matrices such as PM. Moreover, it is necessary a preliminary process of derivatization in order to raise the volatility of polar compounds for GC analysis. Therefore, this work started considering and comparing the most used derivatization techniques, the silylation and esterification, in order to choose the one that would reach the level of sensitivity, specificity and applicability necessary for environmental analysis⁷-⁹. From the results, the best technique is silylation with N, O-bis (trimethylsilyl)-trifluoroacetammide (BSTFA): the developed method permits to analyze 15 carboxylic acids with detection limits lower than 3ng/m3. The study was extended in order to analyze other compuonds present in WSOC: in particular sugars, that are specific molecular markers that provide important information on sources of organic compounds in PM. The derivatization reaction was optimized, in particular the parameters that affect the yield and the sensitivity of the analytical method, such as time and reaction temperature and the amount or composition of the reagents. We used a mathematical/statistical approach to assess simultaneously the effect of these factors with a small number of experimental tests. We used an experimental design model: a central composite design¹⁰. This allowed the development of a method for the simultaneous determination of 15 acids and 7 sugars present in atmospheric particles in concentration level less than 10ng/m3 in most cases. The procedure was successfully applied to a series of samples of atmospheric particles, both fine (PM2.5) and ultrafine (PM1), within an integrated environmental monitoring of a local area around Bologna (Project Moniter , developed by ARPAER): consisted of two sampling campaigns, one on summer and one on winter, over 8 sites with urban, rural or intermediate characteristics. The analytical data obtained have provided significant information on the contribution from anthropogenic urban transport and domestic heating, the contribution due to agriculture and the state of formation of organic substances originating from processes in the atmosphere (SOA). In the development of innovative methods applicable to environmental monitoring, it has also studied a new method for analysis of PM samples, based on direct thermal desorption, with in situ derivatization and gas chromatography coupled with mass spectrometry time of flight (IDTD-GC-TOFMS)¹¹-¹³. This study was conducted in collaboration with Prof. Ralf Zimmermann and his research group at the Helmholtz Zentrum in Munich (Germany). This technique enables the analysis of environmental samples avoiding the most common extraction treatments because the analytes are thermally directly desorbed from filter and can enter the chromatographic column. The addition of the silylating agent on the filter permits a gas-phase reaction of polar compounds. The application of IDTD-GC-TOFMS in PM2.5 samples simultaneously led to the identification of both polar (such as sugars) and apolar species (e.g. alkanes and polycyclic aromatic hydrocarbons), with great advantage in terms of time consuming and loss of analytes during sample pretreatment. In conclusion, it had been developed analytical methods suitable for environmental monitoring in order to obtain information on chemical composition that can be integrated with other information, i.e. physical, meteorological, environmental, for an enhanced approach to the study of particulate air pollution and its impact on the environment and human health. --- 1: R. Ladji, N. Yassaa, A. Cecinato, B.Y. Meklati. Atmospheric Research, 86: 249–260, 2007. 2: Q. Zhang, D.R. Worsnop, M.R. Canagaratna, J.L. Jimenez. Atmos. Chem. Phys., 5: 3289–3311, 2005. 3: W.F. Rogge, M.A. Mazurek, L.M. Hildemann, G.R. Cass, B.R.T. Simoneit. Atmospheric Environment, 27A: 1309–1330, 1993. 4: J.J. Schauer, W.F. Rogge, L.M. Hildemann, M.A. Mazurek, G.R. Cass, B.R.T. Simoneit. Atmospheric Environment, 30: 3837–3855, 1996. 5: J.J. Schauer, G.R. Cass. Environmental Science and Technology, 34: 1821–1832, 1996. 6: B.R.T. Simoneit, V.O. Elias, M. Kobayashi, K. Kawamura, A.I. Rushdi, P.M. Medeiros, W.F. Rogge, B.M. Didyk. Environmental Science and Technology, 38: 5939–5949, 2004. 7: K. Kawamura, K. Ikushima. Environmental Science and Technology, 27: 2227–2235, 1993. 8: H. Wang, K. Kawamura, K.F. Ho, S.C. Lee. Environmental Science and Technology, 40: 6255–6260, 2006. 9: Z. Yue, M.P. Fraser. Atmospheric Environment, 38: 3253–3261, 2004. 10: G.E.P. Box, K.B. Wilson. Journal of the Royal Statistical Society, series B, 13(1): 1-45, 1951. 11: S.S.H. Ho, J.Z. Yu, J.C. Chow, B. Zielinska, J.G.Watson, J.J. Schauer. Journal of Chromatography A, 1200: 217-227, 2008. 12: .D. Hays, R.J. Lavrich. Trends in Analytical Chemistry, 26: 88-102, 2007. 13: J. Schnelle-Kreis, M. Sklorz, A. Peters, J. Cyrys, R. Zimmermann. Atmospheric Environment, 39: 7702-7714, 2005.

Vengono illustrati e interpretati i dati di composizione ionica ed elementare di Particolato atmosferico PM10, M2.5 e PM1 ottenuti nell'ambito del progetto triennale Moniter (http://www.arpa.emr.it/pubblicazioni/moniter/generale_619.asp ) finanziato dalla Regione Emilia Romagna e coordinato dall'ARPA ER. Compito dell'UO Ciamician è stato quello di analizzare oltre 800 campioni diaerosol atmosferico raccolto in varie località della Provincia di Bologna al fine di studiare l'influenza delle emissioni atmosferiche dell'Inceneritore municipale della città presso Granarolo. I risultati finali sonostati presentati a dicembre 2011. Gli autori sono in attesa di autorizzazione per la pubblicazione

Several epidemiological studies have shown the negative effect of Particulate Matter (PM) on human health; in particular, it was shown that the finer fractions of PM (PM2.5 and PM1) can penetrate deeply into the lung and cause negative effects which ranges from cardiovascular and neurotoxic effects to cancer (Künzli and Perez, 2009). For this reason, plans to suggest right policy controls for human health protection have to taken into account the most relevant emission sources for the area under investigation and how PM concentrations at receptors can be influenced by transport, mixing and transformation processes. In this work, the collaboration among different partners, such as Apulian Agency for Environmental Protection, University of Bari, University of Lecce, CNR-ISAC, allowed to obtain important results by a PM monitoring campaign performed in Apulia Region. PM10 has been collected in five different sampling sites (Torchiarolo, Galatina, Taranto- Tamburi, Palagiano e Montalbano-Ostuni) at different distance from the iron and steel pole of Taranto. The main interest on Taranto is due to the presence of several activities of high impact as very wide industrial area close to the town and the numerous maritime and military activities in the harbour area (Amodio et al., 2008). Therefore, the aim of this study was the chemical characterization of PM10 samples in order to estimate emission sources contributions and to evaluate how these sources influence pollutants concentrations at the sampling sites. Fifteen daily samples have been collected in the period from February 2009 to March 2009. The chemical characterization of the samples has been performed to determine inorganic components, Polycyclic Aromatic Hydrocarbons, carbonaceous fractions and metals. It was found that the sampling site close to the steel plant (Taranto-Tamburi) was affected by iron and manganese concentrations greater than those observed in other sites (an order of magnitude) when the wind direction allowed the transport from the plant to the receptor. The contribution of crustal matter source has been evaluated by means of titanium and silicon concentrations: almost the same values were observed in the different sites and it was explained according to a regional contribution of this source. On the contrary, the chemical concentrations of sodium and chlorine allowed to highlight the local contributions of marine aerosol. Finally, the relevance of biomass burning for domestic heating in the sampling site of Torchiarolo e Galatina has been shown by high concentrations of PAHs and potassium, in agreement with high aluminium concentrations. Moreover, SEM - EDS analysis allowed the morphological characterization of PM: the collected images were used both to obtain particles statistical size and shape distributions and to characterize chemical species. In the sampling period, Comprehensive Air Quality Model with extensions (CAMX) was used to evaluate meteorological dispersion condition of the atmosphere. Starting and edge domain concentrations of chemical species have been evaluated by taking into account data obtained by CHIMERE model. Source emissions data, available in Apulia Region Emission Inventory, were processed by means of GEM-PP code. Measured pollutants concentrations were compared to those obtained by applying the model and the underestimation of real concentrations were observed. It was explained taking into account some sources not considered in Emission Inventory and the chemical mechanism, performed by the model, for the simulation of secondary particulate matter formation. Künzli, N., Perez, L., (2009). Swiss Medical Weekly 139(17-18), 242-250. Amodio, M. et al., (2008). ChemiChemical Engineering Transactions 16, 193-199.

The study of the past global climatic variations plays a very important role in the comprehension of present climate change and in the assessment of its future development. In particular, it is important to understand the natural variability of the climatic system and in which way human activity is responsible for these variations. Paleoclimatic studies are based on information preserved in Natural Archives, sites around the world where it is possible to obtain indirect data, the so called proxy data, about climate-dependant parameters. Polar Ice Caps are one of the better natural archives both in terms of preservation and completeness. During the last two decades many drillings were performed in both Antarctic and Greenlandic ice caps, and in particular three ice cores from East Antarctic plateau have allowed to investigate a long period of past climate. These are Vostok ice core (Petit et al, 1999), Dome Fuji ice core (Goto-Azuma, 2006), and EPICA (European project for Ice Coring in Antarctica) Dome C ice core (EPICA community members, 2004). The last one covers 800,000 years BP (Before Present), and contains the oldest ice ever drilled. It is possible to collect many information from ice cores, and this work is focused on mineral dust concentration variability in the East Antarctic ice sheet, with the aim to create a very high resolution dust record. Atmospheric dust that has reached and deposited on Antarctic ice sheet from remote areas, are considered one of the best-preserved and detailed proxy data. Dust concentration, size distribution, isotopic signature and mineralogical studies give us information about climate variability and potential source areas (PSA), moreover it is possible to reconstruct paleoatmospheric circulation and back trajectories through models. In this way it is possible to contribute in increasing knowledge about coupled ocean-atmospheric system dynamics and about the important and not completely understood climate forcing role of the dust. In this work dust concentration was investigated through a new laser particle counter technique. The Laser Sensor Abakus Particle Counter (LS) operates through a 670 nm wavelength laser beam. The analysis were performed melting ice samples, from the new deep ice core drilling in Talos Dome (East Antarctica), in continuous through the Continuous Flow Analysis (CFA) system. The work was carried out in Alfred Wegner Institute for Polar and Marine Research (AWI – Bremerhaven, Germany) in the contest of a collaboration between Germany, Switzerland and Italian groups. This work is part of the TALDICE (TALos Dome ICE core) project, leaded by Italy, that involved also Germany, France, Switzerland and UK. Talos Dome (TD: 159°11’ E, 72°49’ S; 2315 m a.s.l.) is a peripheral dome at the edge of the East Antarctic plateau, 250 km from the Ross Sea and 300 km from the Southern Ocean. Dust concentration and size distribution analysis were performed also with the Beckmann Coulter Multisizer 3 (CC), a device which works through an electric principle, in a clean room located in the Environmental Science Department of Milano Bicocca University. The LS device has provided two kinds of outputs: bag mean values and high resolution data. Both signals were processed and have generated two dust records (with low and high resolution). In this work it was discussed part of the dust record that covered a period of about 60,000 years between the end of the last deglaciation (about 12,000 years BP) and Marine Isotopic Stage 4 (MIS 4, 70,000 years BP). The LS dust record was compared at first with the CC one and the good agreement between the two devices confirmed that LS is a suitable tool for this kind of studies. Than it was compared with other records from different ice cores drilled in East Antarctic plateau and on the Greenland ice sheet. In particular, the EPICA project ice cores drilled in Dome C (EDC) and Dronning Maud Land (EDML) were considered, together with Northern Hemisphere NGRIP (North Greenland Ice core project) ice core. In addition, dust records and stable isotope records (δ18O, δD) from Antarctic ice core (TD, EDC, EDML) and only δ18O record for NGRIP ice core were considered too. The comparison between TD dust record and the above-mentioned records provided interesting information about climatic condition in the TD area, atmospheric circulation and the link between climate and PSA during late Quaternary. It was noticed that TD dust record shows a good agreement with EDC and EDML ones, both for climatic variation at millennial and multimillennial scale. During Last Glacial Maximum (LGM) the dust flux in the three drilling site is comparable, but this is not the case for MIS 4, where TD shows an average lower flux value compared to LGM. This result is shown for the first time by the TD ice core. Consequently, now it is possible to suppose that dust transport mechanisms towards TD, EDC and EDML were the same during the last glacial period. Anyway, dust signal in TD is ambiguous, probably because it is the result of interaction of many factors. Likely, during LGM, very cool air masses extended above the Antarctic plateau, even in TD area, have created a subsidence condition which haven’t allowed the cyclonic perturbation to penetrate the interior of Antarctica continent. In fact, the Polar Front has moved towards lower latitude in that period, maintaining far away these “disturbances”. It is possible to hypothesize that this condition was weaker during MIS 4 and that the cyclonic perturbation have interfered with air masses coming from the plateau, and prevented dust flux towards TD. So it could be said that TD site shows a global climatic signal and it is sensitive to Southern Ocean conditions, in particular in the Indo-Pacific sector (like EDC), during LGM, instead it shows a mixed signal during MIS 4. In this period the TD area probably is sensitive partly to Southern Ocean Indo-Pacific sector, and partly to a more local Ross Sea sector condition. This work even highlights the significance of the PSA sensitivity to climate variations and to small temperatures changes during the glacial period. Many studies have proved that the main dust source area in East Antarctic plateau is the Southern South America, more precisely Patagonia (Delmonte et al., 2008a & 2004b; Basile et al., 1997), and a new work (Delmonte et al., 2009) shows that this is substantial even for TD. In fact It was noticed in TD, EDC and EDML, three clear oscillation over LGM, two of these likely due to periglacial activity related to the development of the Patagonian ice cap (Sugden et al., 2009). Through comparison with EDML δ18O, it has been possible to identify some Antarctic Isotopic Maximum (AIM, isotope peaks along the record) that correspond to dust minimum in TD dust record. AIMs have a correspondence with another kind of fast oscillation in the Northern Hemisphere, called Dansgaard/Oeschger events. These are abrupt warm events, more or less 2,000 years long and followed by less rapid cooling. EDML δ18O profile shows that AIMs are in antiphase with the D/O event, and data from TD ice core confirm this behaviour. This difference between Northern and Southern Hemisphere is explained by a recent theory called “Bipolar Seesaw”, that tries to understand the mechanisms with which the two Hemisphere were alternatively warmed up and cooled down. Although some works (Stenni et al., submitted; Barker et al., 2009; Lamy et al., 2007; EPICA community members, 2006; Stocker et al., 2003; Blunier et al., 2001 e 1998) tried to understand the dynamics involved in the Bipolar Seesaw theory, many uncertainties and doubts must be solved and the new results obtained by TD ice core have given a very important contribution for a better comprehension of this climatic trend. At least it is possible to assert that the new Talos Dome ice core results obtained in this work provided: - a confirmation of dust validity as climatic variability indicator; - an important contribution on next models studies and on a better understanding of coupled ocean-atmospheric circulation dynamics and their climatic pattern; - a confirmation of previous studies obtained by other ice cores from different drilling sites; - new information that will give an important motivation to improve these kind of studies, in particular on new coastal deep ice cores. The future work and perspective will be the conclusion of high resolution data processing, focusing mainly on the Holocene period. In particular analysis on the first 70 m of TD ice core will be carry out, with the aim to reconstruct the last 2,000 years of climate history. With the same goal, some shallow firn cores that were drilled along a traverse from TD to Dome C and from TD to Dumont d’Urville (East Antarctic coastal site on Pacific Sector and where is located the French Antarctic Station) in the frame of ITASE (International Trans Antarctic Scientific Expedition) project during 1998 and 2001 drilling campaign, will be analyse. This studies represent a real challenge for the future because, in the contest of a proved global warming, it will be essential to understand how and in which proportion natural variability and human activities are responsible of this change.

PIXE and XRF are very effective techniques in atmospheric aerosol investigation, therefore they are extensively used by the authors. In this work an inter-laboratory comparison of the results obtained analysing several samples (collected on different substrata) with both techniques is presented: the samples were analysed by PIXE (in Florence, at the 3 MV Tandetron accelerator of LABEC laboratory) and by XRF (in Genoa and Milan, where two Oxford XRF instruments are operational). The results of the three sets of measurements are in good agreement for all the analysed samples. The aim of this work was also to compare PIXE and XRF performance in atmospheric aerosol analysis with the routine set-up currently in use at the three laboratories, to determine the best technique to be applied depending on the substratum used for aerosol sampling and the main elements of interest for each specific research project. Results of the comparison between the minimum detection limits of both techniques will be shown for all the measured elements, for different substrata (Teflon, polycarbonate and cellulose mixed esters).

La valutazione del contenuto dei metalli in traccia nel particolato atmosferico attraverso estrazione chimica sequenziale ha ottenuto sempre maggiore attenzione negli ultimi anni (Smichowski et al., 2005). Tale studio costituisce infatti un potente strumento nell’interpretazione del comportamento tossicologico e ambientale del PM e può essere di aiuto nello stimare il contributo di diverse sorgenti al PM campionato.

Per una nazione come l’Italia, che possiede gran parte delle opere d’arte mondiali, la conservazione e la salvaguardia dei beni culturali costituisce un obiettivo di primaria importanza. In quest’ottica si colloca lo studio dell’impatto ambientale sul Battistero di Firenze, situato nel centro urbano della città, realizzato attraverso il campionamento dell’aerosol atmosferico presso due delle tre porte dell’edificio, ovvero Porta Nord, esposta direttamente al traffico veicolare, e Porta Sud, influenzata indirettamente dalle emissioni veicolari. Allo scopo di confrontare la composizione del particolato atmosferico in prossimità delle due porte con quella della zona circostante, un terzo campionamento è stato effettuato sul tetto del Museo dell’Opera del Duomo, sito considerato come background dell’area. Del particolato totale sospeso sono stati misurati la concentrazione in massa in atmosfera, la componente ionica solubile e il carbonio non carbonatico. I risultati ottenuti indicano nei processi di combustione le principali sorgenti di particolato atmosferico nel centro di Firenze. Presso la Porta Nord del Battistero, le emissioni da traffico veicolare contribuiscono in modo rilevante alle concentrazioni degli inquinanti misurati. Inoltre, lo studio dimostra che, anche all’aperto, il flusso di visitatori incrementa la quantità d’aerosol atmosferico, influenzandone la composizione. Ogni monumento situato all’aperto è quindi esposto agli agenti inquinanti caratteristici della zona in cui è ubicato e solo un ampio monitoraggio locale può fornire i dati necessari per individuare strategie idonee alla protezione e conservazione del patrimonio culturale.