Incineration of sewage sludge and recovery of residue ash as building material: A valuable option as a consequence of the COVID-19 pandemic

Circular economy principles were adopted by European Commission, to support a sustainable growth. They contain general rules that should be considered in all situations. At present, during pandemic, some waste disposal practices are under evaluation to guarantee safety conditions. For example, in view of the recent results reporting the presence of SARS-CoV-2 virus in sewage sludge, the possibility that it diffuses in the environment is alarming. The situation may result critical in densely populated cities, which are the largest sources of sewage sludge. In this frame the diffused practice of reuse of this waste in agriculture is under revision. In this context, incineration may represent a valuable alternative strategy to manage sewage sludge during pandemic. Indeed, due to thermal treatment, the destruction of organic micropollutants and pathogens, eventually present in the waste, is guarantee. Moreover, it is fundamental to highlight that also if the management of sewage sludge changes, the ash resulting from its combustion may have suitable reuse opportunities, and their landfilling should be avoided. This work presents the available possibilities of sewage sludge ash recovery in building applications and shows the results obtained by the analysis of their sustainability. The approach is based on the use of embodied energy and carbon footprint values, to make a simple and fast new method able to be a suitable tool to support and promote sustainability also in critical situations (such as pandemic) and when all the information about a technology are not available, making not possible to perform a full-LCA approach. This work aims to be not only a reference paper for promotion of strategies able to increase waste management safety, but also an example showing that circular economy principles should be pursued also if boundary conditions can change.

Beyond waste: new sustainable fillers from fly ashes stabilization, obtained by low cost raw materials

A sustainable economy can be achieved only by assessing processes finalized to optimize the use of resources. Waste can be a relevant source of energy thanks to energy-from-waste processes. Concerns regarding the toxic fly ashes can be solved by transforming them into resource as recycled materials. The commitment to recycle is driven by the need to conserve natural resources, reduce imports of raw materials, save landfill space and reduce pollution. A new method to stabilize fly ash from Municipal Solid Waste Incinerator (MSWI) at room temperature has been developed thanks to COSMOS-RICE LIFE+ project (www.cosmos-rice.csmt.eu). This process is based on a chemical reaction that occurs properly mixing three waste fly ashes with rice husk ash, an agricultural by-product. COSMOS inert can replace critical raw materials (i.e. silica, fluorspar, clays, bentonite, antimony and alumina) as filler. Moreover the materials employed in the stabilization procedure may be not available in all areas. This paper investigates the possibility of substituting silica fume with corresponding condensed silica fume and to substitute flue-gas desulfurization (FGD) residues with low-cost calcium hydroxide powder. The removal of coal fly ash was also considered. The results will be presented and a possible substitution of the materials to stabilize fly ash will be discussed.

Quetiapine and its metabolite norquetiapine: translation from in vitro pharmacology to in vivo efficacy in rodent models

BACKGROUND AND PURPOSE

Quetiapine has a range of clinical activity distinct from other atypical antipsychotic drugs, demonstrating efficacy as monotherapy in bipolar depression, major depressive disorder and generalized anxiety disorder. The neuropharmacological mechanisms underlying this clinical profile are not completely understood; however, the major active metabolite, norquetiapine, has been shown to have a distinct in vitro pharmacological profile consistent with a broad therapeutic range and may contribute to the clinical profile of quetiapine.

EXPERIMENTAL APPROACH

We evaluated quetiapine and norquetiapine, using in vitro binding and functional assays of targets known to be associated with antidepressant and anxiolytic drug actions and compared these activities with a representative range of established antipsychotics and antidepressants. To determine how the in vitro pharmacological properties translate into in vivo activity, we used preclinical animal models with translational relevance to established antidepressant-like and anxiolytic-like drug action.

KEY RESULTS

Norquetiapine had equivalent activity to established antidepressants at the noradrenaline transporter (NET), while quetiapine was inactive. Norquetiapine was active in the mouse forced swimming and rat learned helplessness tests. In in vivo receptor occupancy studies, norquetiapine had significant occupancy at NET at behaviourally relevant doses. Both quetiapine and norquetiapine were agonists at 5-HT1A receptors, and the anxiolytic-like activity of norquetiapine in rat punished responding was blocked by the 5-HT1A antagonist, WAY100635.

CONCLUSIONS AND IMPLICATIONS

Quetiapine and norquetiapine have multiple in vitro pharmacological actions, and results from preclinical studies suggest that activity at NET and 5-HT1A receptors contributes to the antidepressant and anxiolytic effects in patients treated with quetiapine.

Metal fractionation in soils and assessment of environmental contamination in Vallecamonica, Italy

Metal contamination was investigated in soils of the Vallecamonica, an area in the northern part of the Brescia province (Italy), where ferroalloy industries were active for a century until 2001. The extent in which emissions from ferroalloy plants affected metal concentration in soils is not known in this area. In this study, the geogenic and/or anthropogenic origin of metals in soils were estimated. A modified Community Bureau of Reference sequential chemical extraction method followed by inductively coupled plasma optical emission spectroscopy (ICP-OES) analyses were employed to evaluate the potential bioavailability of Al, Cd, Mn, Fe, Cr, Zn, and Pb in soils. Principal component analysis (PCA) was used to assess the relationships among metal sources in soil samples from different locations. This approach allowed distinguishing of different loadings and mobility of metals in soils collected in different areas. Results showed high concentrations and readily extractability of Mn in the Vallecamonica soils, which may suggest potential bioavailability for organisms and may create an environmental risk and potential health risk of human exposure.

Airborne particulate matter (PM) filter analysis and modeling by total reflection X-ray fluorescence (TXRF) and X-ray standing wave (XSW)

This work is presented as an improvement of a recently introduced method for airborne particulate matter (PM) filter analysis [1]. X-ray standing wave (XSW) and total reflection X-ray fluorescence (TXRF) were performed with a new dedicated laboratory instrumentation. The main advantage of performing both XSW and TXRF, is the possibility to distinguish the nature of the sample: if it is a small droplet dry residue, a thin film like or a bulk sample. Another advantage is related to the possibility to select the angle of total reflection to make TXRF measurements. Finally, the possibility to switch the X-ray source allows to measure with more accuracy lighter and heavier elements (with a change in X-ray anode, for example from Mo to Cu). The aim of the present study is to lay the theoretical foundation of the new proposed method for airborne PM filters quantitative analysis improving the accuracy and efficiency of quantification by means of an external standard. The theoretical model presented and discussed demonstrated that airborne PM filters can be considered as thin layers. A set of reference samples is prepared in laboratory and used to obtain a calibration curve. Our results demonstrate that the proposed method for quantitative analysis of air PM filters is affordable and reliable without the necessity to digest filters to obtain quantitative chemical analysis, and that the use of XSW improve the accuracy of TXRF analysis.

Total reflection X-ray fluorescence (TXRF) for direct analysis of aerosol particle samples

Atmospheric aerosol particles have a great impact on the environment and on human health. Routine analysis of the particles usually involves only the mass determination. However, chemical composition and phases provide fundamental information about the particles' origins and can help to prevent health risks. For example, these particles may contain heavy metals such as Pb, Ni and Cd, which can adversely affect human health. In this work, filter samples were collected in Brescia, an industrial town located in Northern Italy. In order to identify the chemical composition and the phases of the atmospheric aerosols, the samples were analysed by means of total reflection X-ray fluorescence (TXRF) spectrometry with a laboratory instrument and X-ray microdiffraction at Synchrotron Daresbury Laboratories, Warrington (Cheshire, UK). The results are discussed and correlated to identify possible pollution sources. The novelty of this analytical approach is that filter samples for TXRF were analysed directly and did not require chemical pretreatment to leach elements from the aerosol particulates. The results of this study clearly show that TXRF is a powerful technique for the analysis of atmospheric aerosols on 'as-received' filters, thereby leaving samples intact and unaltered for possible subsequent analyses by other methods. In addition, the low detection limits for many elements (low ng/cm2) indicate that this method may hold promise in various application fields, such as nanotechnology.

Analysis of crystalline phases in airborne particulate matter by two-dimensional X-ray diffraction (XRD2)

In this work, the potentiality of two-dimensional X-ray diffraction (XRD(2)) to characterise aerosol particles collected on commercial glass filters is presented. Indeed, even if routine analysis usually requires only mass determination, and rarely chemical composition, phase determination is fundamental to recognize the primary or secondary origin of the particulate matter and thus to determine the main sources of the pollution and to model contamination events. The experiments were performed at Daresbury Synchrotron (UK) Laboratory on 14.1 Beamline. The analysis of filters collected in Tuscany (Italy) is discussed with particular attention to the presence of arsenic sulfide. The first results of these experiments are very promising, showing the presence of unexpected compounds in the particulate matter of the investigated area.

Isolation, biochemical characterization and ultrastructural analysis of the limbic system-associated membrane protein (LAMP), a protein expressed by neurons comprising functional neural circuits

The limbic system-associated membrane protein (LAMP) is a cell surface glycoprotein expressed by cortical and subcortical regions of the mammalian CNS that comprise or receive direct projections from limbic system structures. The early and restricted expression of LAMP has led to its postulated role in neural development. Purification and biochemical characterization of LAMP was performed in order to ascertain its relationship to other, well-defined cell surface proteins in the nervous system. Subcellular fractionation, immunoaffinity chromatography, and Western blots of rodent and bovine hippocampus revealed that LAMP is an integral membrane protein with a molecular mass of 64-68 kDa and a pI of 5.2-5.5. Deglycosylation of LAMP indicates that it contains N-linked high mannose or hybrid sugars and a minor amount of sialic acid. The LAMP protein exhibits an identical molecular mass in developing hippocampus and in several different brain regions in the adult. No cross-reactivity was obtained using the monoclonal antibody that recognizes the HNK-1 carbohydrate epitope, a complex sulfated moiety expressed on members of a large family of glycoproteins. Immunocytochemical analysis at the ultrastructural level reveals that LAMP immunoreactivity is exhibited by neurons in a stereotyped pattern throughout limbic system areas. Glial cells are not immunoreactive. In the adult, LAMP-immunoreactive membrane patches are present exclusively postsynaptically on neuronal somata and dendrites. Myelinated and unmyelinated axons are not stained in any brain region examined. Analysis of LAMP expression in the developing CNS during synaptogenesis demonstrates that LAMP is located on growing axons and both pre- and postsynaptically at forming terminal complexes. Double-labeling studies of the hippocampal neurons grown in vitro reveal that the LAMP epitope is extracellular and is expressed on neurofilament- and microtubule-associated protein 2-positive neurites. Cells expressing glial fibrillary acidic protein are not LAMP-immunoreactive. These results demonstrate that in the adult brain, LAMP is expressed almost exclusively by the postsynaptic (target) elements in limbic circuits, but that during development, all components of the surface of the growing neuron contain LAMP. The stereotyped anatomical pattern of expression of LAMP in the developing and mature brain and its biochemical characteristics suggest that LAMP is a unique, system-associated membrane glycoprotein that is distinct from previously identified, developmentally important cell surface proteins.