Search

Abstract Exposures to fine particulate matter (PM $$_1$$ 1 ) have been associated with health impacts, but the understanding of the PM $$_1$$ 1 concentration-response (PM $$_1$$ 1 -CR) relationships, especially at low PM $$_1$$ 1 , remains incomplete. Here, we present novel data using a methodology to mimic lung exposure to ambient air (2 $$

Peat is the main constituent of cultivation substrates and a precious non-renewable fossil material. Peatlands provide important ecosystem services and allow the absorption and storage of carbon. Protecting peatlands helps tackle climate change and contributes to biodiversity conservation. Due to its importance, it is necessary to implement strategies to reduce the use of peat, such as replacing it with biomass-based alternative growing media constituents, such as Sphagnum moss. In this study, we compared the metal release and binding properties at two different pH, antioxidant activity, and total phenolic content of peat and Sphagnum moss from the Tierra del Fuego (TdF) region of southern Patagonia. Levels of the elements were determined by inductively coupled plasma mass spectrometry (ICP-MS), while the types and amounts of functional groups were characterized and compared using Fourier transform infrared (FTIR) spectroscopy. The total phenol level and antioxidant capacity were assessed using the Folin-Ciocalteu method and 2,2-diphenyl-1-picrylhydrazyl test. There are generally higher concentrations of leachable elements in peat than in Sphagnum moss at pH = 2, except Cs, Rb, Ti, and Zr. In contrast, at pH = 5, levels of all leached elements are highest in Sphagnum moss. Sphagnum moss shows a higher metal adsorption capacity than peat, except for Be, Mn, Tl, and Zn. Finally, the results showed that both matrices contained similar total phenolic contents: 0.018 ± 0.011 mg gallic acid equivalent (GAE) per gram dry sample for peat and 0.020 ± 0.007 mg GAE g-1 for Sphagnum moss. Instead, Sphagnum moss extracts showed a significantly higher antioxidant activity [0.026 ± 0.028 mmol Trolox equivalents (TE) g-1] than that estimated in peat (0.009 ± 0.005 mmol TE g-1). Humic acids, carboxylic acids, and phenolic and lignin groups were identified as the functional groups that mainly determined the antioxidant activity of the Sphagnum moss compared to peat. The present study resulted in an advancement of knowledge of these materials for more thoughtful future use and possible replacements.

The predicted increase in demand for minor metals for modern technologies raises major concerns regarding potential environmental concentration increases. Among the minor metals, lithium (Li) is particularly noteworthy due to growing demand for battery production. Concerns have been raised about the impact on biota of increasing Li concentrations in the environment. To expand the knowledge of the effects of Li on plants, garden cress (Lepidium sativum L.), a model plant for ecotoxicity assay, was tested in a 72 h test in Petri plates. The results showed a stimulation effect of Li at the lowest concentration (Li chloride 10 mg L−1) on seed germination and primary root elongation. Conversely, higher Li concentrations (50 and 150 mg L−1) caused a progressive impairment in both parameters. A genotoxic effect of Li on root cells, evaluated through the alkaline comet assay, was observed at each concentration tested, particularly at 150 mg L−1 Li chloride. Elemental analysis showed that Li accumulated in the seedlings in a dose–concentration relationship, confirming its ability to be readily absorbed and accumulated in plants. Given the likely increase in Li levels in the environment, further research is required to clarify the toxicity mechanisms induced by Li on growth and nucleic acids.

Abstract Peatlands in southern South America (Tierra del Fuego region, TdF) play a key role in the ecological dynamics of Patagonia. It is, therefore, necessary to increase our knowledge and awareness of their scientific and ecological value to ensure their conservation. This study aimed to assess the differences in the distribution and accumulation of elements in peat deposits and Sphagnum moss from the TdF. Chemical and morphological characterization of the samples was carried out using various analytical techniques, and total levels of 53 elements were determined. Furthermore, a chemometric differentiation based on the elemental content of peat and moss samples was performed. Some elements (Cs, Hf, K, Li, Mn, Na, Pb, Rb, Si, Sn, Ti and Zn) showed significantly higher contents in moss samples than in peat samples. In contrast, only Mo, S and Zr were significantly higher in peat samples than in moss samples. The results obtained highlight the ability of moss to accumulate elements and to act as a means to facilitate the entry of elements into peat samples. The valuable data obtained in this multi-methodological baseline survey can be used for more effective conservation of biodiversity and preservation of the ecosystem services of the TdF.

X-ray phase-contrast tomography offers a highly sensitive 3D imaging approach to investigate different disease-relevant networks at levels ranging from single cell through to intact organ. The authors present a concomitant study of the evolution of tissue damage and inflammation in different organs affected by the disease in the murine model for multiple sclerosis.

Abstract In this work, the application of a time resolved multi-contrast beam tracking technique to the investigation of the melting and solidification process in metals is presented. The use of such a technique allows retrieval of three contrast channels, transmission, refraction and dark-field, with millisecond time resolution. We investigated different melting conditions to characterize, at a proof-of-concept level, the features visible in each of the contrast channels. We found that the phase contrast channel provides a superior visibility of the density variations, allowing the liquid metal pool to be clearly distinguished. Refraction and dark-field were found to highlight surface roughness formed during solidification. This work demonstrates that the availability of the additional contrast channels provided by multi-contrast X-ray imaging delivers additional information, also when imaging high atomic number specimens with a significant absorption.

Environmental pollution caused by heavy metals has long been considered a relevant threat to ecosystem survival and human health. The use of safer substitutes for the most toxic heavy metals in many industrial applications is discussed as a potential way to face this issue. In this regard, Bi has been proposed for replacing Pb in several production processes. However, few literature records reported on the effects of Bi on living organisms, particularly on plants. In this study, garden cress (Lepidium sativum L.) plants were exposed to different concentrations of Bi nitrate added to soil in growth chambers for 21 days. Results evidenced the toxic effect of Bi on shoot growth, regardless of the Bi nitrate concentration in the soil, paralleled by a similar reduction in the chlorophyll and carotenoid content, a decrease in the nitrogen balance index values, and an impairment of the photosynthetic machinery evaluated by chlorophyll fluorescence image analysis. The presence of Bi in the soil was shown to affect element accumulation in roots and translocation to shoots, with micronutrient content particularly reduced in the leaves of Bi-treated plants. A dose-dependent plant accumulation of Bi to metal concentration in the soil was observed, even if very low metal bioconcentration ability was highlighted. The reduced Bi translocation from roots to shoots in plants exposed to increasing Bi concentrations in the soil is discussed as a possible defense mechanism likely associated with the observed increase of anthocyan and flavonol contents and the activation of photoprotection mechanisms preventing higher damages to the photosynthetic apparatus.

In this survey, we studied the levels of relevant atmospheric elements well known as tracers of vehicular traffic (i.e., Cu, Sb, Sn, Fe, Mn); biomass burning (i.e., K, Rb, Cs, Li, Tl); and soil resuspension (Si, Al, Ca, Ti) in bees and beehive products (honey, wax, pollen, propolis) in five selected sites in the Rome province (Italy). To attentively support the sustainable management of the involved ecosystems, we have enhanced the information variety endowment (fourteen elements, up to 454 samples, five sites, about thirteen thousand analytical determinations) by six sampling campaigns conducted in a one-year survey (2018–2019). The control charts of the considered elements were built for the first time, employing Johnson's probabilistic method in the Rome province area. Thus, we have measured the metal concentration overlap ranges in the selected biomonitor/indicators (as well as medians and distribution) and the overlap bioaccumulation index (OBI) with respect to the lowest (OBI-Lower) and the highest (OBI-Upper) extreme values of the overlap elements’ concentration ranges. The advantage of the OBI is that we can build the control charts by considering the extremes of the bioaccumulation curves of the elements in the matrices simultaneously, thus creating a ranking among the biomonitor/indicators. This study strongly confirms the selected biomonitor/indicators' ability (excluding honey) to reflect the atmospheric deposition of environmental tracers of traffic, biomass burning, and soil in the area of Rome province. Bees and wax resulted in being very strong accumulators of environmental tracers (i.e., Cu, Sn, Mn for traffic; K, Rb, Cs, and Li for biomass burning; and Al, a soil tracer), showing high OBI-U values. For instance, bees have high bioaccumulation surplus with OBI-U values of 68.6 and 92.7 for Cu and Mn, respectively. This confirms their ability as excellent biomonitors when assessing different environmental contamination cases becomes necessary. To a lesser extent, pollen and propolis showed high levels for several tracers for OBI-U and OBI-L values. Honey often showed a univocal bioaccumulation pattern with high OBI-L values (i.e., 53.7; 154.4; and 112.0 for Cu, Fe, and Mn, respectively), indicating the low transfer capability of contaminants from the environment to the final food product, and confirming its good quality. This further confirms that honey is not appropriate as an environmental indicator. Eventually, the OBI-L index can be applied as an early warning signal when the contamination process is in its initial stages. The OBI index boosts the observer's information variety about the performance of bees, wax, pollen, and propolis as element biomonitors in atmospheric ecosystems.

Abstract Margins of wide local excisions in breast conserving surgery are tested through histology, which can delay results by days and lead to second operations. Detection of margin involvement intraoperatively would allow the removal of additional tissue during the same intervention. X-ray phase contrast imaging (XPCI) provides soft tissue sensitivity superior to conventional X-rays: we propose its use to detect margin involvement intraoperatively. We have developed a system that can perform phase-based computed tomography (CT) scans in minutes, used it to image 101 specimens approximately half of which contained neoplastic lesions, and compared results against those of a commercial system. Histological analysis was carried out on all specimens and used as the gold standard. XPCI-CT showed higher sensitivity (83%, 95% CI 69–92%) than conventional specimen imaging (32%, 95% CI 20–49%) for detection of lesions at margin, and comparable specificity (83%, 95% CI 70–92% vs 86%, 95% CI 73–93%). Within the limits of this study, in particular that specimens obtained from surplus tissue typically contain small lesions which makes detection more difficult for both methods, we believe it likely that the observed increase in sensitivity will lead to a comparable reduction in the number of re-operations.

Food product safety and quality are closely related to the elemental composition of food. This study combined multielement analysis and chemometric tools to characterize 237 extra-virgin olive oil (EVOO) samples from 15 regions of Italy, and to verify the possibility of discriminating them according to different quality factors, such as varietal or geographical origin or whether they were organically or traditionally produced. Some elements have antioxidant properties, while others are toxic to humans or can promote oxidative degradation of EVOO samples. In particular, the antioxidant activity of oils’ hydrophilic fraction was estimated and the concentrations of 45 elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). At first, univariate and multivariate analyses of variance were used to compare the element concentrations, and statistically significant differences were found among samples from different regions. Successively, discriminant classification approaches were used to build a model for EVOO authentication, considering, in turn, various possible categorizations. The results have indicated that chemometric methods coupled with ICP-MS have the potential to discriminate and characterize the different types of EVOO, and to provide “typical” elemental fingerprints of the various categories of samples.

Characterizing nanoparticles (NPs) distribution in multiple and complex metastases is of fundamental relevance for the development of radiological protocols based on NPs administration. In the literature, there have been advances in monitoring NPs in tissues. However, the lack of 3D information is still an issue. X-ray phase-contrast tomography (XPCT) is a 3D label-free, non-invasive and multi-scale approach allowing imaging anatomical details with high spatial and contrast resolutions. Here an XPCT qualitative study on NPs distribution in a mouse brain model of melanoma metastases injected with gadolinium-based NPs for theranostics is presented. For the first time, XPCT images show the NPs uptake at micrometer resolution over the full brain. Our results revealed a heterogeneous distribution of the NPs inside the melanoma metastases, bridging the gap in spatial resolution between magnetic resonance imaging and histology. Our findings demonstrated that XPCT is a reliable technique for NPs detection and can be considered as an emerging method for the study of NPs distribution in organs.

The RHAPS (Redox-Activity And Health-Effects Of Atmospheric Primary And Secondary Aerosol) project was launched in 2019 with the major objective of identifying specific properties of the fine atmospheric aerosol from combustion sources that are responsible for toxicological effects and can be used as new metrics for health-related outdoor pollution studies. In this paper, we present the overall methodology of RHAPS and introduce the phenomenology and the first data observed. A comprehensive physico-chemical aerosol characterization has been achieved by means of high-time resolution measurements (e.g., number size distributions, refractory chemical components, elemental composition) and low-time resolution analyses (e.g., oxidative potential, toxicological assays, chemical composition). Preliminary results indicate that, at the real atmospheric conditions observed (i.e., daily PM1 from less than 4 to more than 50 μg m−3), high/low mass concentrations of PM1, as well as black carbon (BC) and water soluble Oxidative Potential (WSOP,) do not necessarily translate into high/low toxicity. Notably, these findings were observed during a variety of atmospheric conditions and aerosol properties and with different toxicological assessments. Findings suggest a higher complexity in the relations observed between atmospheric aerosol and toxicological endpoints that go beyond the currently used PM1 metrics. Finally, we provide an outlook to companion papers where data will be analyzed in more detail, with the focus on source apportionment of PM1 and the role of source emissions on aerosol toxicity, the OP as a predictive variable for PM1 toxicity, and the related role of SOA possessing redox-active capacity, exposure-response relationships for PM1, and air quality models to forecast PM1 toxicity.

The ability of lichen transplant Evernia prunastri (L.) Ach. to reflect air concentration and spatial distribution of 7 polychlorinated dibenzodioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), and 23 polychlorinated biphenyls (PCBs) was evaluated through the construction of a wide and dense biomonitoring network. For this purpose, 23 lichen transplants were placed in a highly polluted area in Central Italy, characterized by the presence of different local emission sources such as a power plant, a steel plant, vehicular traffic, and domestic heating. The high spatial resolution data obtained from lichens were used to map the spatial distribution of the studied compounds, useful to identify the location and strength of target compounds sources over the territory. The maps showed that the highest concentrations of the pollutants were detected, as expected, in the sites close to the power plant and to the steel plant, confirming their important role as persistent pollutants emission sources. The statistical analysis performed on the spatially resolved data allowed us to identify the steel plant as the main source of PCDD/Fs, while PCBs were emitted by both the steel plant and the power plant. Finally, the efficiency of lichen transplants to reflect PCDD/Fs and PCBs atmospheric concentrations was assessed by comparing lichen data with POPs deposition measured by bulk deposition samplers at sites impacted by intensive emission sources; good results were achieved from the comparison (R2 > 0.79). Lichen transplants have demonstrated to be suitable biomonitors of POPs, allowing to obtain a high spatial monitoring network. The low-cost biomonitoring and experimental approach described in this study can be applied to other monitoring campaigns for identifying localizing emission sources of POPs in areas contaminated by several disaggregated sources.

We report a qualitative study on central nervous system (CNS) damage that demonstrates the ability of X-ray phase contrast tomography (XPCT) to confirm data obtained with standard 2D methodology and permits the description of additional features that are not detected with 2D or other 3D techniques. In contrast to magnetic resonance or computed tomography, XPCT makes possible the high-resolution 3D imaging of soft tissues classically considered “invisible” to X-rays without the use of additional contrast agents, or without the need for intense processing of the tissue required by 2D techniques. Most importantly for studies of CNS diseases, XPCT enables a concomitant multi-scale 3D biomedical imaging of neuronal and vascular networks ranging from cells through to the CNS as a whole. In the last years, we have used XPCT to investigate neurodegenerative diseases, such as Alzheimer’s disease (AD) and multiple sclerosis (MS), to shed light on brain damage and extend the observations obtained with standard techniques. Here, we show the cutting-edge ability of XPCT to highlight in 3D, concomitantly, vascular occlusions and damages, close associations between plaques and damaged vessels, as well as dramatic changes induced at neuropathological level by treatment in AD mice. We corroborate data on the well-known blood-brain barrier dysfunction in the animal model of MS, experimental autoimmune encephalomyelitis, and further show its extent throughout the CNS axis and at the level of the single vessel/capillary.

Water-soluble and insoluble fractions of airborne particulate matter (PM) exhibit different toxicological potentials and peculiar mechanisms of action in biological systems. However, most of the research on the oxidative potential (OP) of PM is focused exclusively on its water-soluble fraction, since experimental criticisms were encountered for detaching the whole PM (soluble and insoluble species) from field filters. However, to estimate the actual potential effects of PM on human health, it is essential to assess the OP of both its water-soluble and insoluble fractions. In this study, to estimate the total OP (TOP), an efficient method for the detachment of intact PM10 from field filters by using an electrical toothbrush was applied to 20 PM10 filters in order to obtain PM10 water suspensions to be used for the DCFH, AA and DTT oxidative potential assays (OPDCFH, OPAA and OPDTT). The contribution of the insoluble PM10 to the TOP was evaluated by comparing the TOP values to those obtained by applying the three OP assays to the water-soluble fraction of 20 equivalent PM10 filters. The OP of the insoluble fraction (IOP) was calculated as the difference between the TOP and the WSOP. Moreover, each PM10 sample was analyzed for the water-soluble and insoluble fractions of 10 elements (Al, Cr, Cs, Cu, Fe, Li, Ni, Rb, Sb, Sn) identified as primary elemental tracers of the main emission sources in the study area. A principal component analysis (PCA) was performed on the data obtained to identify the predominant sources for the determination of TOP, WSOP, and IOP. Results showed that water-soluble PM10 released by traffic, steel plant, and biomass burning is mainly responsible for the generation of the TOP as well as of the WSOP. This evidence gave strength to the reliability of the results from OP assays performed only on the water-soluble fraction of PM. Lastly, the IOPDCFH and IOPDTT were found to be principally determined by insoluble PM10 from mineral dust.

Over the last years, various acellular assays have been used for the evaluation of the oxidative potential (OP) of particular matter (PM) to predict PM capacity to generate reactive oxygen (ROS) and nitrogen (RNS) species in biological systems. However, relationships among OP and PM toxicological effects on living organisms are still largely unknown. This study aims to assess the effects of atmospheric PM-selected components (brake dust - BD, pellet ash - PA, road dust - RD, certified urban dust NIST1648a - NIST, soil dust - S, coke dust - C and Saharan dust - SD) on the model plant A. thaliana development, with emphasis on their capacity to induce oxidative stress and root morphology alteration. Before growing A. thaliana in the presence of the PM-selected components, each atmospheric dust has been chemically characterized and tested for the OP through dithiothreitol (DTT), ascorbic acid (AA) and 2′,7′-dichlorofluorescin (DCFH) assays. After the exposure, element bioaccumulation in the A. thaliana seedlings, i.e., in roots and shoots, was determined and both morphological and oxidative stress analyses were performed in roots. The results indicated that, except for SD and S, all the tested dusts affected A. thaliana root system morphology, with the strongest effects in the presence of the highest OPs dusts (BD, PA and NIST). Principal component analysis (PCA) revealed correlations among OPs of the dusts, element bioaccumulation and root morphology alteration, identifying the most responsible dust-associated elements affecting the plant. Lastly, histochemical analyses of NO and O2− content and distribution confirmed that BD, PA and NIST induce oxidative stress in A. thaliana, reflecting the high OPs of these dusts and ultimately leading to cell membrane lipid peroxidation. Keywords: Arabidopsis thaliana, Atmospheric dust, Element bioaccumulation, Oxidative potential, Oxidative stress, Root morphology

Peroxisomes are important in plant physiological functions and stress responses. Through the production of reactive oxygen and nitrogen species (ROS and RNS), and antioxidant defense enzymes, peroxisomes control cellular redox homeostasis. Peroxin (PEX) proteins, such as PEX7 and PEX5, recognize peroxisome targeting signals (PTS1/PTS2) important for transporting proteins from cytosol to peroxisomal matrix. pex7-1 mutant displays reduced PTS2 protein import and altered peroxisomal metabolism. In this research we analyzed the role of PEX7 in the Arabidopsis thaliana root system exposed to 30 or 60 μM CdSO4. Cd uptake and translocation, indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) levels, and reactive oxygen species (ROS) and reactive nitrogen species (RNS) levels and catalase activity were analyzed in pex7-1 mutant primary and lateral roots in comparison with the wild type (wt). The peroxisomal defect due to PEX7 mutation did not reduce Cd-uptake but reduced its translocation to the shoot and the root cell peroxisomal signal detected by 8-(4-Nitrophenyl) Bodipy (N-BODIPY) probe. The trend of nitric oxide (NO) and peroxynitrite in pex7-1 roots, exposed/not exposed to Cd, was as in wt, with the higher Cd-concentration inducing higher levels of these RNS. By contrast, PEX7 mutation caused changes in Cd-induced hydrogen peroxide (H2O2) and superoxide anion (O2●−) levels in the roots, delaying ROS-scavenging. Results show that PEX7 is involved in counteracting Cd toxicity in Arabidopsis root system by controlling ROS metabolism and affecting auxin levels. These results add further information to the important role of peroxisomes in plant responses to Cd.

Bees and their products are useful bioindicators of anthropogenic activities and could overcome the deficiencies of air quality networks. Among the environmental contaminants, mercury (Hg) is a toxic metal that can accumulate in living organisms. The first aim of this study was to develop a simple analytical method to determine Hg in small mass samples of bees and beehive products by cold vapor atomic fluorescence spectrometry. The proposed method was optimized for about 0.02 g bee, pollen, propolis, and royal jelly, 0.05 g beeswax and honey, or 0.1 g honeydew with 0.5 mL HCl, 0.2 mL HNO3, and 0.1 mL H2O2 in a water bath (95 °C, 30 min); samples were made up to a final volume of 5 mL deionized water. The method limits sample manipulation and the reagent mixture volume used. Detection limits were lower than 3 µg kg−1 for a sample mass of 0.02 g, and recoveries and precision were within 20% of the expected value and less than 10%, respectively, for many matrices. The second aim of the present study was to evaluate the proposed method’s performances on real samples collected in six areas of the Lazio region in Italy.

Potential exposure to toxic elements initially occurs during gestation and after birth via breast milk, which is the principal source of nutrients for infants during the first months of life. In this study, we evaluated whether maternal oral supplementation with a multi-strain probiotic product can protect infants from exposure to arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) via breast milk. In-vitro studies of the bacterial strains present in this probiotic product showed a high bacterial tolerance for As, Cd, Hg, and Pb, and good binding capacity for Cd, Hg, and Pb (72%, 81%, and 64%, respectively) within 1 h of contact. We evaluated concentrations (5 mg L−1 for Cd and Pb, and 2 mg L−1 for Hg) that largely exceeded the provisional tolerable weekly intake of these toxic elements via food or water applicable for human consumption. Changes in the levels of these elements in breast milk and newborn stools were evaluated in the control (orally supplemented with placebo) and experimental (orally supplemented with probiotic) groups at birth (t0), 15 days (t15), and 30 days (t30) after delivery. Elemental analysis of breast milk did not show significant differences between the control and experimental groups at different stages of lactation; however, stool samples obtained from newborns of mothers supplemented with the probiotic product showed that Cd levels were significantly reduced (by 26%) at t15 compared with the levels of the controls. Our data did not show an association between concentration of toxic elements in breast milk and that in newborn stools. Indeed, the concentration of Cd, Hg, and Pb in breast milk decreased during the lactation period, whereas the levels of these elements in newborn stools were stable over time. Although our in-vitro data indicate that the consortium of these probiotic strains can absorb toxic compounds, this study was limited by its small sample size and potential uncontrolled confounding effects, such as maternal diet and lifestyle. Therefore, we could not confirm whether prophylactic use of this probiotic product can reduce the absorption of toxic elements. The risk assessment in the studied population evidenced a margin of exposure (MOE) of 1, or between 1 and 10 for Pb, and lower than 50 for As. This poses a potential risk for breastfed infants, indicating that interventions aimed to avoid breastfeeding-related health risks remain a major challenge in public health. Keywords: Breast milk, Meconium, Probiotic, Biomonitoring, Toxic element, Risk assessment

Bee health and beehive products’ quality are compromised by complex interactions between multiple stressors, among which toxic elements play an important role. The aim of this study is to optimize and validate sensible and reliable analytical methods for biomonitoring studies and the quality control of beehive products. Four digestion procedures, including two systems (microwave oven and water bath) and different mixture reagents, were evaluated for the determination of the total content of 40 elements in bees and five beehive products (beeswax, honey, pollen, propolis and royal jelly) by using inductively coupled plasma mass and optical emission spectrometry. Method validation was performed by measuring a standard reference material and the recoveries for each selected matrix. The water bath-assisted digestion of bees and beehive products is proposed as a fast alternative to microwave-assisted digestion for all elements in biomonitoring studies. The present study highlights the possible drawbacks that may be encountered during the elemental analysis of these biological matrices and aims to be a valuable aid for the analytical chemist. Total elemental concentrations, determined in commercially available beehive products, are presented.

The mass concentration of atmospheric particulate matter (PM) has been systematically used in epidemiological studies as an indicator of exposure to air pollutants, connecting PM concentrations with a wide variety of human health effects. However, these effects can be hardly explained by using one single parameter, especially because PM is formed by a complex mixture of chemicals. Current research has shown that many of these adverse health effects can be derived from the oxidative stress caused by the deposition of PM in the lungs. The oxidative potential (OP) of the PM, related to the presence of transition metals and organic compounds that can induce the production of reactive oxygen and nitrogen species (ROS/RNS), could be a parameter to evaluate these effects. Therefore, estimating the OP of atmospheric PM would allow us to evaluate and integrate the toxic potential of PM into a unique parameter, which is related to emission sources, size distribution and/or chemical composition. However, the association between PM and particle-induced toxicity is still largely unknown. In this commentary article, we analyze how this new paradigm could help to deal with some unanswered questions related to the impact of atmospheric PM over human health.

Increasing arsenic environmental concentrations are raising worldwide concern for its impacts on human health and ecosystem functionality. In order to cope with arsenic contamination, bioremediation using fungi can represent an efficient, sustainable, and cost-effective technological solution. Fungi can mitigate arsenic contamination through different mechanisms including bioaccumulation. In this work, four soil saprotrophic fungi Absidia spinosa, Purpureocillium lilacinum, Metarhizium marquandii, and Cephalotrichum nanum, isolated from soils with naturally high arsenic concentrations, were tested for their ability to tolerate different sodium arsenite concentrations and accumulate As in different cultural conditions. pH medium after fungal growth was measured to study pH variation and metabolic responses. Arsenic bioaccumulation and its influence on the uptake of other elements were investigated through multi-elemental analysis using hydride generation atomic fluorescence spectrometry (HG-AFS), inductively coupled plasma mass spectrometry (ICP-MS) and inductively coupled plasma optical emission spectroscopy (ICP-OES). Considering the increasing interest in siderophore application for metal bioremediation, the production of siderophores and their affinity for both Fe and As were also evaluated. All species were able to tolerate and accumulate As in their biomass in all of the tested conditions and produced siderophores with different affinities for Fe and As. The results suggest that the tested fungi are attractive potential candidates for the bioremediation of As contaminated soil and worthy of further investigation.

Washed and unwashed Arundo donax L. (A. donax) leaves were analyzed for elements, and results were compared with element concentrations detected in river water and particulate matter (PM) Samples were collected along a river in an urban and industrial hot spot of Central Italy, where element concentrations show relevant spatial gradients both in air and river water. The aim of this study is to identify the role of the two environmental matrices on leaves composition. Element concentrations of washed and unwashed leaves were compared to differentiate between the superficial deposition and the uptake into leaf tissues of elements. Water-soluble and -insoluble element concentrations were measured in PM10 samples collected on membrane filters by using innovative high spatial resolution samplers. The comparison among leaf and atmospheric concentrations of PM10 elements showed a similar trend for Ni, Mo, Cr, Ti, and Fe, which are reliable tracers of the PM10 contribution by steel plant and vehicular traffic. Soluble species appeared to be mainly bounded into leaf tissues, while insoluble species were deposited on their surface. On the other hand, element concentrations detected in washed A. donax leaves were poorly correlated with those measured in river water samples. The obtained results proved that A. donax leaves can be used as reliable biomonitors for the evaluation of the atmospheric concentrations of some PM10 elemental components.

Ethane 1,2-diamineborane (EDAB) is an alkyl-containing amine-borane adduct with improved hydrogen desorption properties as compared to ammonia borane. In this work, it is reported the high temperature thermolytic decomposition of EDAB. Thermolysis of EDAB has been investigated by concomitant thermogravimetry-differential thermal analysis-mass spectrometry experiments. EDAB shows up to four H2 desorption events below 1000 °C. Small fractions of CH4, C2H4 and CO/CO2 are also observed at moderate-high temperatures. The solid-state thermolysis product has been characterized by means of different structural and chemical methods, such as X-ray diffraction, Raman spectroscopy, Scanning electron microscopy, Elemental analysis, and X-ray photoelectron spectroscopy (XPS). The obtained results indicate the formation of a ternary borocarbonitride compound with a poorly-crystalline graphitic-like structure. By contrast, XPS measurements show that the surface is rich in carbon and nitrogen oxides, which is quite different to the bulk of the material.

Graphene grown on crystalline metal surfaces is a good candidate to act as a buffer layer between the metal and organic molecules that are deposited on top, because it offers the possibility to control the interaction between the substrate and the molecules. High-resolution angular-resolved ultraviolet photo electron spectroscopy (ARPES) is used to determine the interaction states of iron phthalocyanine molecules that are adsorbed onto graphene on Ni(111). The iron phthalocyanine deposition induces a quenching of the Ni d surface minority band and the appearance of an interface state on graphene/Ni(111). The results have been compared to the deposition of iron phthalocyanine on graphene/Ir(111), for which a higher decoupling of the organic molecule from the underlying metal is exerted by the graphene buffer layer.

Recent studies have shown the potential of food waste materials as low cost adsorbents for the removal of heavy metals and toxic elements from wastewater. However, the adsorption experiments have been performed in heterogeneous conditions, consequently it is difficult to compare the efficiency of the individual adsorbents. In this study, the adsorption capacities of 12 food waste materials were evaluated by comparing the adsorbents’ efficiency for the removal of 23 elements from complex multi-element solutions, maintaining homogeneous experimental conditions. The examined materials resulted to be extremely efficient for the adsorption of many elements from synthetic multi-element solutions as well as from a heavy metal wastewater. The 12 adsorbent surfaces were analyzed by Fourier transform infrared spectroscopy and showed different types and amounts of functional groups, which demonstrated to act as adsorption active sites for various elements. By multivariate statistical computations of the obtained data, the 12 food waste materials were grouped in five clusters characterized by different elements’ removal efficiency which resulted to be in correlation with the specific adsorbents’ chemical structures. Banana peel, watermelon peel and grape waste resulted the least selective and the most efficient food waste materials for the removal of most of the elements.

A study of spatial variability of PM10 elemental components was conducted in Terni city (Central Italy), situated in an intramountain depression characterized by the presence of several particulate matter emission sources. The meteorological conditions of the Terni basin limit the dispersion and enhance the accumulation of atmospheric pollutants. Thanks to the utilization of new smart samplers, used for the first time and working in parallel at 23 sampling sites, spatially resolved data were obtained. Localizations of the samplers were chosen in order to evaluate the impact of different local PM10 sources. Chemical composition of the samples was determined in combination with a chemical fractioning procedure that allowed us to discriminate water-soluble and residual fractions of analyzed elements in which proved to be a valuable approach for increasing selectivity of elements as source tracers. Spatial variability of elements underlined the contribution of local emission sources and the different dispersion capacity of each element. The city of Terni resulted to be an ideal area to test and validate a new experimental method for the acquisition of spatially resolved data providing the possibility to properly evaluate the spatial variability of PM10 and its chemical components.