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This study is focused on the identification of pollutant sources on black crust (BC) samples from the Monumental Cemetery of Milan (Italy), through a multi-analytical approach based on the determination of stable isotope ratios of carbon, sulphur, and oxygen. Six black crust samples, mainly developed on marble sculptures over a time span of 100-150 years, were analysed. For the first time, δ 13 C was measured for BC samples: δ 13 C values of the pulverized samples (from -1.2 to +1.3 ‰) are very close to the values obtained from the carbonate matrix, whereas after the removal of the matrix through acidification, δ 13 C values of BC samples from Milan range from -27.2 to -22.1 ‰, with no significant variation between samples with different ratios of organic carbon to elemental carbon. In sum, the δ 13 C values obtained for all BC samples fall within the range of anthropogenic emissions such as vehicle traffic, coal combustion and industrial emissions. δ 34 S and δ 18 O values of sulphate from BC samples range from -6.3 to +7.0 ‰ and from +7.6 to +10.5 ‰, respectively. Coupling the analysis of the oxygen isotope ratio with that of sulphur enables a more precise identification of the origin of sulphates: the observed isotopic composition falls in the range typical for anthropogenic emission of sulphur dioxide. Overall, in this study, C, S and O isotopes were combined for the first time to assess pollutant sources on black crust samples: this multi-stable isotope approach allowed to show that the BC formation on monuments from the Monumental Cemetery of Milan mostly results from anthropogenic emissions from fossil fuels combustion by road vehicles and factories, as well as domestic heating., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Antimicrobial treatment of methicillin-resistant Staphylococcus pseudintermedius associated with canine wounds represents an important challenge. The aim of this study was to create a canine wound infection model, Lubbock Chronic Wound Biofilm (LCWB), with a focus on S. pseudintermedius, drawing inspiration from the established human model involving Staphylococcus aureus. Methicillin-resistant S. pseudintermedius 115 (MRSP) and Pseudomonas aeruginosa 700 strains, isolated from dog wounds, were used to set up the LCWB at 24, 48 and 72 h. The LCWBs were evaluated in terms of volume, weight, and microbial CFU/mg. The microbial spatial distribution in the LCWBs was assessed by SEM and CLSM imaging. The best incubation time for the LCWB production in terms of volume (3.38 cm 3  ± 0.13), weight (0.86 gr ± 0.02) and CFU/mg (up to 7.05 × 10 6  CFU/mg ± 2.89 × 10 5 ) was 48 h. The SEM and CLSM images showed a major viable microbial colonization at 48 h with non-mixed bacteria with a prevalence of MRSP on the surface and P. aeruginosa 700 in the depth of the wound. The obtained findings demonstrate the capability of S. pseudintermedius to grow together P. aeruginosa in the LCWB model, representing the suitable model to reproduce the animal chronic wound in vitro., Competing Interests: Declaration of competing interest Authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

COVID-19 has reduced tourism in both museums and historical sites with negative economic effect. The wellbeing and good preservation of monuments is a key factor to encourage again tourism. Historical monuments exposed to outdoor pollution are subjected to well known degradation phenomenon including the formation on their surface of black crusts (BCs) causing blackening and deterioration of the monuments and, as a consequence, a worst fruition by the visitors. The aim of this research is the development and validation of a novel method to characterize and quantify the various components present in the black crusts. SO 2 together with the carbonaceous fraction (i.e. OC, organic carbon, and EC, elemental carbon) represent the main atmospheric pollutants involved in the process of BCs formation which consists in the partial transformation of the carbonate substrate into gypsum where black particles are embedded. A new methodology based on the use of TGA/DSC (Thermogravimetric Analysis/Differential scanning calorimetry) and CHN (Carbon, Hydrogen, Nitrogen) analysis was set up allowing to determine organic carbon and elemental carbon together with other components such as gypsum. Four standard mixtures simulating BCs composition were prepared and analysed by the set-up methodology. The new procedure was subsequently applied to study real BCs samples taken from monuments and historical buildings placed in cities heavily affected by atmospheric pollution and by PCA (principal component analysis) their main features, from the point of view of carbonaceous fraction, were highlighted., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The adverse effects of fine particulate matter (PM) and many volatile organic compounds (VOCs) on human health are well known. Fine particles are, in fact, those most capable of penetrating in depth into the respiratory system. People spend most of their time indoors where concentrations of some pollutants are sometimes higher than outdoors. Therefore, there is the need to ensure a healthy indoor environment and for this purpose the use of an air purifier can be a valuable aid especially now since it was demonstrated that indoor air quality has a high impact on spreading of viral infections such as that due to SARS-COVID19. In this study, we tested a commercial system that can be used as an air purifier. In particular it was verified its efficiency in reducing concentrations of PM10 (particles with aerodynamic diameter less than 10 μm), PM2.5 (particles with aerodynamic diameter less than 2.5 μm), PM1 (particles with aerodynamic diameter less than 1 μm), and particles number in the range 0.3 μm-10 μm. Furthermore, its capacity in reducing VOCs concentration was also checked. PM measurements were carried out by means of a portable optical particle counter (OPC) instrument simulating the working conditions typical of a household environment. In particular we showed that the tested air purifier significantly reduced both PM10 and PM2.5 by 16.8 and 7.25 times respectively that corresponds to a reduction of about 90% and 80%. A clear reduction of VOCs concentrations was also observed since a decrease of over 50% of these gaseous substances was achieved., (Crown Copyright © 2021. Published by Elsevier Inc. All rights reserved.)

In the last decades, many researchers investigated the relation between environmental pollution and the degradation phenomena on the built heritage, because of their rapid increase and growing harmfulness. Consequently, the identification of the main pollution sources has become essential to define mitigation actions against degradation and alteration phenomena of the stone materials. In this way, the present paper is focused on the study of the effect of air pollution on archaeological buildings in Historic Cairo. A multi-methodological approach was used to obtain information about the chemical composition of examined black crusts and to clarify their correlation with the air pollution, specifically the heavy metals and the carbonaceous fraction, their main sources, and their impact on the state of conservation of the studied sites. All specimens were characterized by polarized optical microscopy (POM), X-Ray Diffraction (XRD), Electron Probe Micro Analyser coupled with energy dispersive X-ray spectrometry (EPMA-EDS), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and Thermo-gravimetric analysis (TGA). The study conducted on heavy metals and carbonaceous fraction showed that the greatest contribution of the accumulation of pollutants is attributable to vehicular traffic and industrial activities, the main polluting sources in Cairo city. Furthermore, the comparison with other studies conducted on the carbonaceous fraction in the black crusts coming from both European and non-European cities, has allowed to discriminate the contribution of the primary and secondary polluting sources. Finally, the correlation of the data obtained on the heavy metals and the carbonaceous fraction allowed to formulate important hypothesis about the processes of sulphation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In the present paper total suspended particulate matter (TSP) was collected at the S. Marco Museum in Florence during seasonal monitoring campaigns carried out in 2013 and 2014. The analyses focused on the determination of TSP chemical composition: main ions, organic carbon (OC), elemental carbon (EC), water soluble organic compounds (WSOC) and levoglucosa which is considered the specific marker for wood burning. The analysis of TSP composition in Florence historical centre is of interest to assess what the damage caused to the surfaces of the urban monumental heritage could be. TSP higher value has been registered during December 2013 (58,6 μg/m 3  ± 7,3 μg/m 3 ) while the lower value has been registered in July 2013 (28,5 μg/m 3  ± 2,2 μg/m 3 ). OC and EC were also higher in winter with respect to summer. Sulphate is characterized by quite constant values during all the examined periods while ammonium and nitrate were higher in winter. The seasonal contribution of different sources such as combustion processes (from traffic and wood burning) and soil dust resuspension has been evidenced. In particular during winter a high concentration of levoglucosan, the specific marker for wood combustion, has been determined. Finally, all the data obtained were correlated with those previously determined in another study carried out in 2003 at the Baptistery of San Giovanni in Florence in order to evaluate any possible change in the atmospheric pollution composition., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This paper deals with the analysis of black crust coming from the statue of Oceanus belonging to the Fontana di Trevi (Rome). This monument is undoubtedly one of the main touristic attractions of Rome. During the restoration held between 2014 and 2015, some diagnostic analyses had been carried out. It has been highlighted that the sheltered surfaces suffer the formation of black crust, especially on the marble statues. The possibility to sample those degradation products, together with the unaltered substrate, represented an excellent opportunity to characterize the marble itself, to assess the impact of the urban air pollution on the stone material, and to detect the pollutant on a precise timescale. In fact, it is known that the previous restoration of the fountain had been carried out between 1989 and 1991 then, information about the air pollution over the last 25years can be highlighted, because it has been proved that black crusts act as passive samplers of pollution. In order to fully characterize those samples, several techniques were used, including optical and scanning electron microscopy, X-ray diffraction, laser ablation inductively coupled plasma mass spectrometry, infrared spectroscopy and ion chromatography. Furthermore, a new methodology based on CHN (Carbon, Hydrogen, Nitrogen) analysis has been developed for the quantification of the two main constituents of the carbonaceous fraction present in the black crusts, i.e. OC (organic carbon) and EC (elemental carbon). This integrated approach proposed in the present study allowed us to gain information about the mineralogical phases and the elements within the crusts and at the crust-substrate interface, giving the possibility to identify the pollution sources causing the stone decay within the monument., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In this paper, results on the potential toxicity of ultrafine particles (UFPs d<100nm) emitted by the combustion of logwood and pellet (hardwood and softwood) are reported. The data were collected during the TOBICUP (TOxicity of BIomass COmbustion generated Ultrafine Particles) project, carried out by a team composed of interdisciplinary research groups. The genotoxic evaluation was performed on A549 cells (human lung carcinomacells) using UFPs whose chemical composition was assessed by a suite of analytical techniques. Comet assay and γ-H2AX evaluation show a significant DNA damage after 24h treatment. The interpretation of the results is based on the correlation among toxicological results, chemical-physical properties of UFPs, and the type and efficiency conditions in residential pellet or logwood stoves., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This work is part of the TOBICUP (TOxicity of BIomass Combustion generated Ultrafine Particles) project which aimed at providing the composition of ultrafine particles (UFPs, i.e. particles with aerodynamic diameter, d ae , lower than 100nm) emitted by wood combustion and elucidating the related toxicity. Results here reported are from two ambient monitoring campaigns carried out at an alpine town in Northern Italy, where wood burning is largely diffused for domestic heating in winter. Wintertime and summertime UFP samples were analyzed to assess their chemical composition (i.e. elements, ions, total carbon, anhydrosugars, and polycyclic aromatic hydrocarbons) and biological activity. The induction of the pro-inflammatory cytokine interleukin-8 (IL-8) by UFPs was investigated in two human cells lines (A549 and THP-1) and in human peripheral blood leukocytes. In addition, UFP-induced oxidative stress and genotoxicity were investigated in A549 cells. Ambient UFP-related effects were compared to those induced by traffic-emitted particles (DEP) taken from the NIES reference material "vehicle exhaust particulates". Ambient air UFPs induced a dose-related IL-8 release in both A549 and THP-1 cells; the effect was more relevant on summer samples and in general THP-1 cells were more sensitive than A549 cells. On a weight basis our data did not support a higher biological activity of ambient UFPs compared to DEP. The production of IL-8 in the whole blood assay indicated that UFPs reached systemic circulation and activated blood leukocytes. Comet assay and γ-H2AX evaluation showed a significant DNA damage especially in winter UFPs samples compared to control samples. Our study showed that ambient UFPs can evoke a pulmonary inflammatory response by inducing a dose-related IL-8 production and DNA damage, with different responses to UFP samples collected in the summer and winter periods., (Copyright © 2017 Elsevier B.V. All rights reserved.)

This study aimed to collect, characterize ultrafine particles (UFP) generated from the combustion of wood pellets and logs (softwood and hardwood) and to evaluate their pro-inflammatory effects in THP-1 and A549 cells. Both cell lines responded to UFP producing interleukin-8 (IL-8), with wood log UFP being more active compared to pellet UFP. With the exception of higher effect observed with beech wood log UFP in THP-1, the ability of soft or hard woods to induce IL-8 release was similar. In addition, on weight mass, IL-8 release was similar or lower compared to diesel exhaust particles (DEP), arguing against higher biological activity of smaller size particles. UFP-induced IL-8 could be reduced by SB203580, indicating a role of p38MAPK activation in IL-8 production. The higher activity of beech wood log UFP in THP-1 was not due to higher uptake or endotoxin contamination. Qualitatively different protein adsorption profiles were observed, with less proteins bound to beech UFP compared to conifer UFP or DEP, which may provide higher intracellular availability of bioactive components, i.e. levoglucosan and galactosan, toward which THP-1 were more responsive compared to A549 cells. These results contribute to our understanding of particles emitted by domestic appliances and their biological effects., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

During a sampling campaign, carried out during June 2012, inside some traditional households located in four villages (Phakding, Namche, Pangboche and Tukla) of Mt. Everest region in southern part of the central Himalaya (Nepal), particulate matter (PM) depositions and ashes have been collected. Moreover, outdoor PM depositions have also been analyzed. Chemical characterization of PM depositions and ashes for major ions, organic carbon, elemental carbon (EC), metal content and PAHs (Polycyclic Aromatic Hydrocarbons) allowed identifying, as major contributes to indoor PM, the following sources: biomass burning, cooking and chimney ashes. These sources significantly affect outdoor PM depositions: in-house biomass burning is the major source for outdoor EC and K + as well as biomass burning and cooking activities are the major sources for Polycyclic Aromatic Hydrocarbons., (Copyright © 2016 Elsevier B.V. All rights reserved.)

In this work Positive Matrix Factorization (PMF) was applied to 4-hour resolved PM10 data collected in Milan (Italy) during summer and winter 2006. PM10 characterisation included elements (Mg-Pb), main inorganic ions (NH(4)(+), NO(3)(-), SO(4)(2-)), levoglucosan and its isomers (mannosan and galactosan), and organic and elemental carbon (OC and EC). PMF resolved seven factors that were assigned to construction works, re-suspended dust, secondary sulphate, traffic, industry, secondary nitrate, and wood burning. Multi Linear Regression was applied to obtain the PM10 source apportionment. The 4-hour temporal resolution allowed the estimation of the factor contributions during peculiar episodes, which would have not been detected with the traditional 24-hour sampling strategy., (Copyright © 2011 Elsevier B.V. All rights reserved.)