Chemical transport models often underestimate inorganic aerosol acidity in remote regions of the atmosphere

The inorganic fraction of fine particles affects numerous physicochemical processes in the atmosphere. However, there is large uncertainty in its burden and composition due to limited global measurements. Here, we present observations from eleven different aircraft campaigns from around the globe and investigate how aerosol pH and ammonium balance change from polluted to remote regions, such as over the oceans. Both parameters show increasing acidity with remoteness, at all altitudes, with pH decreasing from about 3 to about −1 and ammonium balance decreasing from almost 1 to nearly 0. We compare these observations against nine widely used chemical transport models and find that the simulations show more scatter (generally R2 < 0.50) and typically predict less acidic aerosol in the most remote regions. These differences in observations and predictions are likely to result in underestimating the model-predicted direct radiative cooling effect for sulfate, nitrate, and ammonium aerosol by 15–39%.

Halogenated Volatile Organic Compounds in Water Samples and Inorganic Elements Levels in Ores for Characterizing a High Anthropogenic Polluted Area in the Northern Latium Region (Italy)

This paper shows a characterization of the organic and inorganic fraction of river waters (Tiber and Marta) and ores/soil samples collected in the Northern Latium region of Italy for evaluating the anthropogenic/natural source contribution to the environmental pollution of this area. For organic compounds, organochloride volatile compounds in Tiber and Marta rivers were analyzed by two different clean-up methods (i.e., liquid–liquid extraction and static headspace) followed by gas chromatography–electron capture detector (GC-ECD) analysis. The results show very high concentrations of bromoform (up to 1.82 and 3.2 µg L−1 in Tiber and Marta rivers, respectively), due to the presence of greenhouse crops, and of chloroform and tetrachloroethene, due to the presence of handicrafts installations. For the qualitative and quantitative assessment of the inorganic fraction, it is highlighted the use of a nuclear analytical method, instrumental neutron activation analysis, which allows having more information as possible from the sample without performing any chemical-physical pretreatment. The results have evidenced high levels of mercury (mean value 88.6 µg g−1), antimony (77.7 µg g−1), strontium (12,039 µg g−1) and zinc (103 µg g−1), whereas rare earth elements show levels similar to the literature data. Particular consideration is drawn for arsenic (414 µg g−1): the levels found in this paper (ranging between 1 and 5100 µg g−1) explain the high content of such element (as arsenates) in the aquifer, a big issue in this area.

Variations in Reactive Oxygen Species Generation by Urban Airborne Particulate Matter in Lung Epithelial Cells—Impact of Inorganic Fraction

Air pollution is associated with numerous negative effects on human health. The toxicity of organic components of air pollution is well-recognized, while the impact of their inorganic counterparts in the overall toxicity is still a matter of various discussions. The influence of airborne particulate matter (PM) and their inorganic components on biological function of human alveolar-like epithelial cells (A549) was investigated in vitro. A novel treatment protocol based on covering culture plates with PM allowed increasing the studied pollutant concentrations and prolonging their incubation time without cell exposure on physical suffocation and mechanical disturbance. PM decreased the viability of A549 cells and disrupted their mitochondrial membrane potential and calcium homeostasis. For the first time, the difference in the reactive oxygen species (ROS) profiles generated by organic and inorganic counterparts of PM was shown. Singlet oxygen generation was observed only after treatment of cells with inorganic fraction of PM, while hydrogen peroxide, hydroxyl radical, and superoxide anion radical were induced after exposure of A549 cells to both PM and their inorganic fraction.

Ion-molecule interactions enable unexpected phase transitions in organic-inorganic aerosol

Atmospheric aerosol particles are commonly complex, aqueous organic-inorganic mixtures, and accurately predicting the properties of these particles is essential for air quality and climate projections. The prevailing assumption is that aqueous organic-inorganic aerosols exist predominately with liquid properties and that the hygroscopic inorganic fraction lowers aerosol viscosity relative to the organic fraction alone. Here, in contrast to those assumptions, we demonstrate that increasing inorganic fraction can increase aerosol viscosity (relative to predictions) and enable a humidity-dependent gel phase transition through cooperative ion-molecule interactions that give rise to long-range networks of atmospherically relevant low-mass oxygenated organic molecules (180 to 310 Da) and divalent inorganic ions. This supramolecular, ion-molecule effect can drastically influence the phase and physical properties of organic-inorganic aerosol and suggests that aerosol may be (semi)solid under more conditions than currently predicted. These observations, thus, have implications for air quality and climate that are not fully represented in atmospheric models.

Deep Inorganic Fraction Characterization of PM10, PM2.5, and PM1 in an Industrial Area Located in Central Italy by Means of Instrumental Neutron Activation Analysis

Atmospheric pollution is an important task in life sciences and, in particular, inorganic fraction characterization is considered as an important issue in this field. For many years, researchers have focused their attention on the particulate matter fraction below 10 μm: in this case, our attention was also focused on PM2.5 (i.e., particles with a size fraction smaller than 2.5 μm) and PM1 (below 1 μm). This paper would like to investigate whether the element accumulation in different granulometric fractions is similar, or whether there are behavior dissimilarities. Among the different analytical techniques, the instrumental neutron activation analysis, an instrumental nuclear method, was used for its peculiarity of investigating the sample without performing any chemical-physical treatment. Forty-two daily samples using the reference method were collected, 15 filters for PM10, 18 for PM2.5, and 12 for PM1; the filters, along with primary standards and appropriate standard reference materials, were irradiated at the National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) R.C.-Casaccia’s Triga MARK II reactor. The irradiations carried out in the Rabbit and Lazy Susan channels allowed for the investigation of 36 elements and the relative Pearson’s correlations between elements and PM-fractions (PM10 vs. PM2.5 was good, whereas PM10 vs. PM1 was the worst). The Enrichment Factors were studied for the three fractions to show how anthropogenic sources have affected the element content. A comparison between these data and element levels determined worldwide showed that our concentrations were lower than those determined in similar scenarios. Furthermore, a statistical approach (source discrimination, hierarchical cluster analysis, principal component analysis) has allowed us to identify similarities between the samples: the airborne filters can be divided in two main groups (i.e., one made of PM10 and PM2.5 filters and one only of PM1 filters), meaning a different element contribution to this fraction coming from other sources present at the site.

Wine traceability and authenticity: approaches for geographical origin, variety and vintage assessment

The aim of this work is to identify and discuss physicochemical wine characteristics, to provide to some extent a link to the vintage, variety, and/or geographical origin. Bibliographic datasets were attempted to provide the main information for topic comprehension, identifying the sources of wine compositional variability and how these can be expressed in terms of the belonging categories. Since all the environmental and technological conditions which vineyard and wine are subjected are rarely known, different sources were inspected. Great importance was given to the study of isotopic composition because of its importance in food frauds detection history. The interaction of the plant genotype with the environmental conditions of the vintage is the main responsible for the wines organic and inorganic fraction variability in terms of both total and relative content. This phenotypical expression, together with human and abiotic variability sources, has been examined since it contains to some extent the information for the discrimination of wines according to their category. Recently, new proton nuclear magnetic resonance (1H NMR) spectroscopy techniques have been under study and, used concurrently to chemometric data management procedures, showed to be an interesting and promising tool for wine characterization according to both vintage and variety.

X-ray powder diffraction of mineral pigments and medicines from the 17th century pharmacy (Spezieria) Santa Maria della Scala in Rome, Italy

The pharmacy (spezieria) Santa Maria della Scala was founded in Rome by the Discalced Carmelites Order in the 17th century, and during the 18th and 19th centuries it became the official supplier of medicines for Vatican Popes. The laboratory and the cases of this spezieria still preserve glass jars with organic and inorganic materials, which were presumably used for medicine and artistic material preparation, whose composition is unknown to date. A research project was initiated with the aim to study the stored materials and the role that the pharmacy played in regional, national and international contexts. In this manuscript, the compounds were analysed through X-ray powder diffraction with the scope to derive the quantitative mineralogical composition of the inorganic fraction, their possible use in pharmacopoeias and as mineral pigments. Most of the analysed samples are salts (sulphates, chlorides, carbonates, phosphates, borates, sulphides), sulphates being the predominant class; oxides were also detected.