Advancements in Portable Voltammetry: A Promising Approach for Iron Speciation Analysis.

Iron, a crucial element in our environment, plays a vital role in numerous natural processes. Understanding the presence and concentration of iron in the environment is very important as it impacts various aspects of our planet's health. The on-site detection and speciation of iron are significant for several reasons. In this context, the present work aims to evaluate the applicability of voltammetry for the on-site determination of iron and its possible speciation using a portable voltammetric analyzer. Voltammetry offers the advantage of convenience and cost-effectiveness. For iron (III) determination, the modification of a glassy carbon electrode (GCE) with an antimony-bismuth film (SbBiFE) using the acetate buffer (pH = 4) as a supporting electrolyte was used. The technique adopted was Square Wave Adsoptive Cathodic Stripping Voltammetry (SW-AdCSV), and we used 1-(2-piridylazo)-2-naphthol (PAN) as the iron (III) ligand. Linearity, repeatability, detection limit, and accuracy were determined using synthetic solutions; then, a Standard Reference Material (SRM) of 1643f Trace Elements in Water (iron content: 93.44 ± 0.78 µg L-1) was used for validation measurements in the real matrix. the accuracy of this technique was found to be excellent since we obtained a recovery of 103.16%. The procedure was finally applied to real samples (tap, lake, and seawater), and the results obtained were compared via Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). The amount of iron found was 207.8 ± 6.6 µg L-1 for tap water using voltammetry and 200.9 ± 1.5 µg L-1 with ICP-OES. For lake water, 171.7 ± 3.8 µg L-1, 169.8 ± 4.1 µg L-1, and 187.5 ± 5.7 µg L-1 were found using voltammetry in the lab both on-site and using ICP-OES, respectively. The results obtained demonstrate the excellent applicability of the proposed on-site voltammetric procedure for the determination of iron and its speciation in water.

Strategies for mercury speciation with single and multi-element approaches by HPLC-ICP-MS.

Mercury (Hg) and its compounds are highly toxic for humans and ecosystems, and their chemical forms determine both their behavior and transportation as well as their potential toxicity for human beings. Determining the various species of an element is therefore more crucial than understanding its overall concentration in samples. For this reason, several studies focus on the development of new analytical techniques for the identification, characterization, and quantification of Hg compounds. Commercially available, hyphenated technology, such as HPLC-ICP-MS, supports the rapid growth of speciation analysis. This review aims to summarize and critically examine different approaches for the quantification of mercury species in different samples using HPLC-ICP-MS. The steps preceding the quantification of the analyte, namely sampling and pretreatment, will also be addressed. The scenarios evaluated comprehend single and multi-element speciation analysis to create a complete guide about mercury content quantification.

Methods for Elemental Analysis of Size-Resolved PM Samples Collected on Aluminium Foils: Results of an Intercomparison Exercise.

Aluminium is the most common substrate in studies using impactors for the measurement of the number or the weight of size-segregated atmospheric particulate matter (PM), as its characteristics perfectly fit impactor requirements. However, its use is not recommended by manufacturers when one of the purposes of the study is the determination of the metal content in the sample. The aim of this work was to develop an efficient analytical procedure for the removal and acid digestion of PM samples collected on aluminium foils by a cascade impactor to perform the determination of metals. The possibility of performing the trace metal analysis of PM samples collected using aluminium foils is of great importance, as it allows the determination of an accurate size distribution and the elemental composition of the PM collected on each impactor stage. Two procedures were optimised by using different digestion and analysis techniques. Both procedures were then applied to the two halves of several Dekati low-pressure impactor (DLPI) samples, and the results were critically compared. The two procedures proved to be effective in the determination of extremely low concentrations of a large suite of analytes in different size fractions of PM emitted by a brake system.

Charge transfer modulation in charge transfer co-crystals driven by crystal structure morphology.

The electronic properties of a charge-transfer (donor-acceptor) semiconducting organic co-crystal, Perylene:F4-TCNQ (PE:F4) (the donor, D, is PE and the acceptor, A, is 2,3,5,6-tetrafluoro-7,7,8,8 tetracyanoquinodimethane (F4)) in its 3 : 2 stoichiometry, are experimentally and theoretically studied. This is performed by means of electron paramagnetic resonance (EPR) and solid state electrochemical techniques, such as cyclic voltammetry (CV) measurements on single crystals. In particular, solid state electrochemistry proves to be an effective tool to probe, on a macroscopic scale, the electronic characteristics of the co-crystal. However, EPR highlights the presence of spin ½ radicals localized on F4 molecules, possibly linked to defects. The experimental findings are discussed on the basis of density functional theory (DFT) based calculations, carried out using both the projector augmented wave (PAW), with "periodic boundary conditions" (pbc), method and the localized orbitals, molecular cluster, approach. In particular, a satisfying agreement is found between the experimental, 0.336 eV (electrochemical), and theoretical, 0.303 eV (PAW), band gaps. Differences with the reported optical bandgap are discussed considering excitonic effects.

On-Site Determination of Methylmercury by Coupling Solid-Phase Extraction and Voltammetry.

A measurement and speciation procedure for the determination of total mercury (HgTOT), inorganic mercury (HgIN), and methylmercury (CH3Hg) was developed and the applicability for on-site determination was demonstrated. A simple, portable sample pretreatment procedure was optimized to extract the analytes. Home-made columns, packed with a new sorbent material called CYXAD (CYPHOS 101 modified Amberlite XAD), were used to separate the two forms of the analyte. HgTOT and CH3Hg were determined by anodic stripping voltammetry (ASV), using a solid gold electrode (SGE). Two certified reference materials (BCR-463 Tuna Fish and Tuna Fish ERM-CE 464) and eight fresh fishes were analyzed. Then, the results that were obtained following the optimized portable procedure were compared with the concentrations obtained, using a direct mercury analyzer (DMA). This quantification, using the two techniques, demonstrated the good performance of the proposed method.

Analytical Methods for the Characterization of Vegetable Oils.

The determination of the authenticity of extra virgin olive oils (EVOOs) has become more interesting in recent years. Italy is the first country in Europe in terms of number of Protected Designation of Origin (PDO) oils, which connects consumers to a feeling of tradition and thus to higher quality standards. This work focused on the consideration of the inorganic content as a possible marker of EVOOs. Ten vegetable oils (VOs), eight Italian EVOOs and seven not Italian EVOOs were analyzed. After pretreatment by acid mineralization, Al, Ba, Ca, Cu, Fe, K, Li, Mg, Mn, Na, P, Sb, Se and Zn were determined by ICP-OES. The electrochemical properties of a selected group of EVOOs and other vegetal oils of different botanical origin were investigated by voltammetry. Carbon paste electrodes (CPEs) were prepared. The features observed in the voltammograms reflect the reactions of electroactive compounds, which are present in the oils. A chemometric treatment of the results was performed to assess the possibility to distinguish (i) the region of provenience considering the inorganic profile; and (ii) the plant species from which each oil was obtained on the basis of the current profile registered during voltammetric analysis. Inorganic composition seems to be a useful marker for the assessment of the geographical origin of an EVOO. The EVOO-CPEs voltammetry seems to have a good ability to distinguish the plant species of origin. This method could be useful to monitor the conservation status of the oils, as the redox profile is linked to the oxidative degradation state.

A Phase I Dose Escalation Study of Oxaliplatin, Cisplatin and Doxorubicin Applied as PIPAC in Patients with Peritoneal Carcinomatosis.

Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC) is an innovative laparoscopic intraperitoneal chemotherapy approach with the advantage of a deeper tissue penetration. Thus far, oxaliplatin has been administered at an arbitrary dose of 92 mg/m2, cisplatin at 7.5 mg/m2 and doxorubicin 1.5 mg/m2. This is a model-based approach phase I dose escalation study with the aim of identifying the maximum tolerable dose of the three different drugs. The starting dose of oxaliplatin was 100 mg/m2; cisplatin was used in association with doxorubicin: 15 mg/m2 and 3 mg/m2 were the respective starting doses. Safety was assessed according to Common Terminology Criteria for Adverse Events (CTCAE version 4.03). Thirteen patients were submitted to one PIPAC procedure. Seven patients were treated with cisplatin and doxorubicin and 6 patients with oxaliplatin; no dose limiting toxicities and major side effects were found. Common adverse events included postoperative abdominal pain and nausea. The maximum tolerable dose was not reached. The highest dose treated cohort (oxaliplatin 135 mg/m2; cisplatin 30 mg/m2 and doxorubicin 6 mg/m2) tolerated PIPAC well. Serological analyses revealed no trace of doxorubicin at any dose level. Serum levels of cis- and oxaliplatin reached a peak at 60-120 min after PIPAC and were still measurable in the circulation 24 h after the procedure. Cisplatin and doxorubicin may be safely used as PIPAC at a dose of 30 mg/m2 and 6 mg/m2, respectively; oxaliplatin can be used at an intraperitoneal dose of 135 mg/m2. The dosages achieved to date are the highest ever used in PIPAC.

Machine Learning Profiling of Alzheimer's Disease Patients Based on Current Cerebrospinal Fluid Markers and Iron Content in Biofluids.

Alzheimer's disease (AD) is the most common form of dementia, characterized by a complex etiology that makes therapeutic strategies still not effective. A true understanding of key pathological mechanisms and new biomarkers are needed, to identify alternative disease-modifying therapies counteracting the disease progression. Iron is an essential element for brain metabolism and its imbalance is implicated in neurodegeneration, due to its potential neurotoxic effect. However, the role of iron in different stages of dementia is not clearly established. This study aimed to investigate the potential impact of iron both in cerebrospinal fluid (CSF) and in serum to improve early diagnosis and the related therapeutic possibility. In addition to standard clinical method to detect iron in serum, a precise quantification of total iron in CSF was performed using graphite-furnace atomic absorption spectrometry in patients affected by AD, mild cognitive impairment, frontotemporal dementia, and non-demented neurological controls. The application of machine learning techniques, such as clustering analysis and multiclassification algorithms, showed a new potential stratification of patients exploiting iron-related data. The results support the involvement of iron dysregulation and its potential interaction with biomarkers (Tau protein and Amyloid-beta) in the pathophysiology and progression of dementia.

Mechanistic Insights into the Role of Iron, Copper, and Carbonaceous Component on the Oxidative Potential of Ultrafine Particulate Matter.

Transition metals play a key role in the pathogenic potential of urban particulate matter (PM). However, air quality regulations include exposure limits only for metals having a known toxic potential like Pb, As, Cd, and Ni, neglecting other transition metals like Fe and Cu. Fe and Cu are mainly found in the water-soluble fraction of PM. However, a fraction of the ions may persist strongly bound to the particles, thus potentially acting as surface reactive sites. The contribution of surface ions to the oxidative potential (OP) of PM is likely different from that of free ions since the redox activity of metals is modulated by their local chemical environment. The aim of this study was to investigate how Fe and Cu bound to carbonaceous particles affect the OP and associated toxicity of PM toward epithelial cells and macrophages. Carbonaceous nanoparticles (CNPs) having well-defined size were loaded with controlled amounts of Cu and Fe. The effect of Cu and Fe on the OP of CNPs was evaluated by electronic paramagnetic resonance (EPR) spectroscopy associated with the spin-trapping technique and correlated with the ability to induce cytotoxicity (LDH, WST-1), oxidative stress (Nrf2 translocation), and DNA damage (comet assay) on lung macrophages (NR8383) and/or epithelial cells (RLE-6TN). The release of pro-inflammatory cytokines (TNF-α, MCP-1, and CXCL2) by macrophages and epithelial cells was also investigated. The results indicate a major contribution of surface Cu to the surface reactivity of CNPs, while Fe has a minor role. At the same time, Cu increases the cytotoxicity of CNPs and their ability to induce oxidative stress and DNA damage. In contrast, surface Fe increases the release of pro-inflammatory cytokines by macrophages. Overall, these results confirm the role of Cu and Fe in PM toxicity and suggest that the total metals content in PM might be a better indicator of pathogenicity than water-soluble metals.

Development of an easy portable procedure for on-site determination of mercury and methylmercury.

A portable measurement and speciation procedure for inorganic mercury (HgIN) and methylmercury (CH3Hg) was developed. A portable sample pretreatment was optimized to determine total mercury content. A new home-made sorbent (CYXAD, CHYPOS 101 modified Amberlite XAD), was prepared to separate HgIN and CH3Hg. Mercury species were determined using square wave anodic stripping voltammetry (SW-ASV) with a solid gold electrode (SGE) and using a portable potentiostat. A certified reference material, five freeze-dried samples and three fresh samples were analysed with conventional voltammetric analyzer, after dissolution of the samples in microwave oven, and with a portable potentiostat after the mild eating procedure. The results obtained by SW-ASV were compared with those obtained using Direct Mercury Analyser (DMA). The quantification with the portable method is comparable to that obtained with the DMA. Retention tests showed the selectivity of CYXAD for HgIN, its stability and the possibility to re-use the same aliquot of resin.

Influence of start-up phase of an incinerator on inorganic composition and lead isotope ratios of the atmospheric PM10.

A municipal solid waste incinerator (MSWI) was installed in a peripheral area of the city of Turin. In this study, we evaluated the contribution of this plant to the massive concentration of PM10, to its chemical composition and to the distribution of the lead isotopes during the start-up phase.We assessed the inorganic composition of PM10 collected in the vicinity of the Turin incinerator by inductively coupled plasma atomic emission spectroscopy (ICP-AES), magnetic sector inductively coupled plasma mass spectrometer (SF-ICP-MS) and ion chromatography (IC). The lead isotope ratios in PM10 samples were determined by SF-ICP-MS by a method developed and optimized using experimental design approach. Element trends and data chemometric treatment evidence that the vehicular traffic, increased in this area due to the opening of the MSWI plant, and, to a lesser degree, the direct incinerator emissions influence As, Cd, Cr, Cu, Ba, Mo, Pb, Sn and Zn concentrations. As a whole, however, the element concentrations in PM10 and the Enrichment Factors (EFs) were comparable with the values reported for other urban sites and target pollutant concentrations of MSWI emissions, namely Cd, Cr, Cu and Pb, were lower than in PM10 emitted from older MSWIs. This confirms that incinerators of new installation have a lower impact on atmospheric PM10 composition thanks to stricter current legislation and up-to-date technologies. The lead isotope ratios investigation allowed to distinguish the diverse sources (crustal, vehicular traffic and MSWI) that influence lead concentration in PM10 collected near incinerator during start-up phase.

Optimization of a sequential extraction procedure for trace elements in Arctic PM10.

In this work, a two-step sequential extraction scheme for the determination of trace elements in Arctic PM10 samples was optimized by using two certified reference materials (CRMs). By means of an experimental design for qualitative variables, the five most common extracting solutions for particulate matter (PM) sequential extraction (high purity water (HPW), 0.032 M HNO3, 0.022 M HCl, 0.11 M CH3COOH, and 0.012 M CH3COOH/CH3COONH4 buffer) and two different extraction methods (stirring and ultrasounds) were compared. The purpose of the study was the identification of the procedure which gives the best estimation of the anthropogenic portion of the elements present in PM10 samples. The use of ultrasounds instead of stirring induced a low but significant decrease of the extraction of all the elements and a decrease in the repeatability of the procedure. Diluted HNO3 was the extractant which allowed to maximize the extraction of anthropogenic elements (As, Cd, Pb, Zn) with respect to crustal ones (Al, Si, Ti). The optimized procedure proved successful in avoiding contaminations and, therefore, suitable to be applied to PM samples having extremely low concentrations, such as samples collected in polar or other remote areas. The chosen procedure was applied to ten Arctic PM10 samples, allowing for a better identification of their sources. Indeed, it was possible to hypothesize that even though the concentrations of As, Cd, K, Mg, Mn, and Ni in spring and summer were different, their mobility and, therefore, their chemical form in the analyzed PM10 samples were probably similar. Graphical abstract.

The Inorganic Component as a Possible Marker for Quality and for Authentication of the Hazelnut's Origin.

The inorganic component of hazelnuts was considered as a possible marker for geographical allocation and for the assessment of technological impact on their quality. The analyzed samples were Italian hazelnuts of the cultivar Tonda Gentile Romana and Turkish hazelnuts of the cultivars Tombul, Palaz and Çakildak. The hazelnuts were subjected to different drying procedures and different conservative methods. The concentration of 13 elements, namely Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Ni, P, Sn, Sr and Zn, were quantified by inductively coupled plasma optical emission spectroscopy (ICP-OES). All the samples were previously digested in a microwave oven. Before proceeding with the analysis of the samples, the whole procedure was optimized and tested on a certified reference material. The results show that the inorganic component: (i) can represent a fingerprint, able to identify the geographical origin of hazelnuts, becoming an important quality marker for consumer protection; (ii) is strongly influenced by the treatments undergone by the investigated product during all the processing stages. A pilot study was also carried out on hazelnuts of the cultivar Tonda Gentile Trilobata Piemontese, directly harvested from the plant during early development to maturity and analyzed to monitor the element concentration over time.

A Portable Setup for the Voltammetric Determination of Total Mercury in Fish with Solid and Nanostructured Gold Electrodes.

A simple procedure for field fish sample pretreatment was developed. This treatment in combination with square wave anodic stripping voltammetry (SW-ASV) with solid gold electrodes (SGE) and gold nanoparticle-modified glassy carbon electrodes (AuNPs-GCE) was applied for the determination of total mercury content. A certified reference material (CRM, Tuna Fish BCR 463), ten freeze-dried samples of canned tuna and two fresh fish samples were analysed both with a bench-top voltammetric analyser after microwave digestion and with a portable potentiostat after mild eating using a small commercial food warmer. The results obtained by the two SW-ASV approaches and by a Direct Mercury Analyser (DMA), the official method for mercury determination, were in very good agreement. In particular, (i) the results obtained with in field procedure are consistent with those obtained with the conventional microwave digestion; (ii) the presence of gold nanoparticles on the active electrode surface permits an improvement of the analytical performance in comparison to the SGE: the Limit of Quantification (LOQ) for mercury in fish-matrix was 0.1 µg L-1 (Hg cell concentration), corresponding to 0.06 mg kg-1 wet fish, which is a performance comparable to that of DMA. The pretreatment proposed in this study is very easy and applicable to fresh fish; in combination with a portable potentiostat, it proved to be an interesting procedure for on-site mercury determination.

Magnetic Iron Oxide Nanoparticles: Synthesis, Characterization and Functionalization for Biomedical Applications in the Central Nervous System.

Magnetic Nanoparticles (MNPs) are of great interest in biomedicine, due to their wide range of applications. During recent years, one of the most challenging goals is the development of new strategies to finely tune the unique properties of MNPs, in order to improve their effectiveness in the biomedical field. This review provides an up-to-date overview of the methods of synthesis and functionalization of MNPs focusing on Iron Oxide Nanoparticles (IONPs). Firstly, synthesis strategies for fabricating IONPs of different composition, sizes, shapes, and structures are outlined. We describe the close link between physicochemical properties and magnetic characterization, essential to developing innovative and powerful magnetic-driven nanocarriers. In conclusion, we provide a complete background of IONPs functionalization, safety, and applications for the treatment of Central Nervous System disorders.

Magnetic Nanoparticles in the Central Nervous System: Targeting Principles, Applications and Safety Issues.

One of the most challenging goals in pharmacological research is overcoming the Blood Brain Barrier (BBB) to deliver drugs to the Central Nervous System (CNS). The use of physical means, such as steady and alternating magnetic fields to drive nanocarriers with proper magnetic characteristics may prove to be a useful strategy. The present review aims at providing an up-to-date picture of the applications of magnetic-driven nanotheranostics agents to the CNS. Although well consolidated on physical ground, some of the techniques described herein are still under investigation on in vitro or in silico models, while others have already entered in-or are close to-clinical validation. The review provides a concise overview of the physical principles underlying the behavior of magnetic nanoparticles (MNPs) interacting with an external magnetic field. Thereafter we describe the physiological pathways by which a substance can reach the brain from the bloodstream and then we focus on those MNP applications that aim at a nondestructive crossing of the BBB such as static magnetic fields to facilitate the passage of drugs and alternating magnetic fields to increment BBB permeability by magnetic heating. In conclusion, we briefly cite the most notable biomedical applications of MNPs and some relevant remarks about their safety and potential toxicity.

Chromium, nickel, and cobalt in cosmetic matrices: an integrated bioanalytical characterization through total content, bioaccessibility, and Cr(III)/Cr(VI) speciation.

The presence of certain metals naturally contained inside raw materials (e.g., pigments) used to produce cosmetics for make-up may represent a serious concern for the final quality and safety of the product. The knowledge of the total concentration of metals is not sufficient to predict their reactivity and their toxicological profile. For these reasons, we set up a comprehensive approach to characterize the content of Co, Cr, and Ni in two raw materials for cosmetic production, a black iron oxide and a pearly pigment, and in a finished product, pearly powder eye shadow. Namely, besides the total metal concentrations, the speciation of chromium and the bioaccessibility of the three metals were assessed. Since no standard method is so far available for hexavalent chromium extraction from cosmetic samples, three approaches were compared (EPA 3060A method, IRSA 16 method, and a Na3PO4 extraction). Results show that Na3PO4 extraction is the most selective one. Cr(VI) was undetectable in black iron oxide and present at very low concentrations (about 0.3 mg/kg) in pearly pigment and in the pearly powder eye shadow samples. The extracted Cr(VI) concentrations are not related to the total Cr content in the samples. Bioaccessibility studies were performed by in vitro extractions with synthetic lacrimal fluids and sweat. Despite the wide range of metal concentrations in the samples, the amounts of bioaccessible elements were undetectable or very low (less than 0.4 mg/kg), thus suggesting that metals in the three samples are present in inert forms. Graphical abstract The possible leaching of metals from cosmetics to biological fluids. Spectroscopic and chromatographic techniques provide complementary information for an integrated bioanalytical approach to risk characterization.

Element variability in lacustrine systems of Terra Nova Bay (Antarctica) and concentration evolution in surface waters.

Major, minor and trace elements were determined in freshwater of lacustrine systems in Terra Nova Bay, along Victoria Land coast, Antarctica, as well as in algae and mosses. The samples were collected during some of the sampling campaigns between 2007 and 2011 (and the one of 2002) within the framework of the Italian National Program of Research in Antarctica (PNRA). Data were processed with chemometric techniques. Results showed that elements typically considered as potential anthropogenic pollutants (e.g. As, Pb, Zn, Cu and Ni) present a strong correlation with the lithogenic elements (e.g. Al, Si, Fe) in all matrices, suggesting that their origin is connected to natural phenomena. Metal concentrations in vegetation samples are in the same range as previously published data. The obtained results were compared with older literature data (since the early '90s) from the same lacustrine systems, in order to present a historical overview of element concentrations. This approach furnishes important information on surface water evolution as a function of time. A considerable variability was observed in metal concentrations but no clear trend was identified. This suggests that their concentration evolution is hardly correlated to specific natural or anthropic phenomena. No evidence of an increase of concentrations over time was apparent. Our results represent new important data about metal concentrations in lacustrine systems in Antarctica, furnishing ranges of values that can be considered as a reference. These data, therefore, could be used to detect or monitor future local and/or global anthropogenic contaminations.

Anodic stripping voltammetry with gold electrodes as an alternative method for the routine determination of mercury in fish. Comparison with spectroscopic approaches.

The applicability to the determination of mercury in tuna of square wave anodic stripping voltammetry (SW-ASV) conducted at both solid gold electrode (SGE) and a gold nanoparticle-modified glassy carbon electrode (AuNPs-GCE) was demonstrated. Mercury content in two certified materials and in ten samples of canned tuna was measured. The performances of the electrodes were compared with one another as well as with two spectroscopic techniques, namely cold vapour atomic absorption spectroscopy (CV-AAS) and a direct mercury analyser (DMA). The results found pointed out that both SW-ASV approaches were suitable and easy-to-use method to monitor mercury concentration in tunas, since they allowed accurate quantification at concentration values lower than the maximum admissible level in this matrix ([Hg]=1mg/kgwet weight,ww). In particular, mercury detection at the AuNPs-GCE showed a LOQ in fish-matrix of 0.1µg/l, corresponding to 0.06mg/kgww, with performance comparable to that of DMA.

Size resolved metal distribution in the PM matter of the city of Turin (Italy).

A work on the characterization of the air quality in the city of Turin was carried out in different sampling periods, reflecting early autumn and winter conditions, including a snow episode during the early 2012 European cold wave. The concentrations of 13 elements in eight size fractions of the aerosol were determined using inductively coupled plasma-mass spectrometry. The collection was carried out with a Andersen MkII cascade impactor. The size distribution of elements allowed the identification of three main behavioural types: (a) elements associated with coarse particles (Cd, Cr, Cu, Fe, Mn, Mo and Sn); (b) elements found within fine particles (As, Co, Pb and V) and (c) elements spread throughout the entire size range (Ni and Zn). Principal Component Analysis allowed to examine the relationships between the inorganic elements and to infer about their origin. Chemometric investigation and assessment of similarity in the distribution led to similar conclusions on the sources. The concentration of gaseous trace pollutants (O3, NOx and VOCs) was determined. The concentrations of these pollutants are scarcely correlated with the metal contents of all the size classes of the PM. The differences found in the O3, NO2 and VOCs levels of the two winter campaigns due to the high photochemical reactivity in the period after the snow episode, do not reflect in differences in the metals distribution in the PM. Since PM metals, NOx and VOC have common sources, this behaviour is due to relevant differences in the transformation and deposition processes.