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Rice cultivation stands as the primary agricultural activity in Asia, generating a substantial amount of agricultural waste. Unfortunately, this waste is often disposed of through burning, contributing to severe environmental, health and climate issues. This study presents the characterization of PCDD/Fs, PCBs and PAHs. The emissions were quantified using a fixed-grid-system biomass plant and measuring the macro-pollutants online and sampling the organic micro-pollutants and metals in isokinetic mode, followed by ISO and CEN standards methods. Additionally, the role of agrochemicals was monitored in terms of metal catalysis resulting in POP emissions. This study provides the comprehensive characterization of the most relevant groups of pollutants (metals, PCDD/Fs, PCBs and PAHs) resulting from agricultural waste combustion. Prominent catalytic metals quantified were Cu (22–48 µg/Nm3) and Fe (78–113 µg/Nm3). Rice straw samples from AJK exhibited higher values of organochlorine micro-pollutants compared to those from Punjab and Sindh, i.e., ∑PCDD/F (2594 > 1493 > 856 pg/Nm3) and ∑PCB (41 > 38 > 30 pg/Nm3), respectively, whereas the organic micro-pollutants ∑c-PAH, indicators of incomplete combustion (PICs), were recorded high in the samples from Sindh followed by Punjab and AJK. The average EF is 100 pg/kg, 2.2 pg/kg and 1053.6 µg/kg for ∑PCDD/F, ∑PCB and ∑c-PAH. This study supports the idea that the phenomena leading to the formation of dioxin and dioxin-like compounds are influenced not only by poor combustion but also by the presence of metal catalysts in the burned fuel. [ABSTRACT FROM AUTHOR]

The European and American methods for the determination of polychlorodibenzo- p-dioxins and polychlorodibenzofurans in stationary source emissions require a high-resolution mass spectrometer detector. At the same time, all of the 17 toxic 2,3,7,8-chlorine-substituted isomers have to be separated by an appropriate chromatographic method. The resulting analysis has long runtimes and sometimes a double-column run is needed, which results in a huge waste of time, money and manual labor. To obtain a fast and cost-effective but still reliable analytical system, a single-column gas chromatography with hydrogen as carrier gas and tandem mass spectrometry detection is proposed. The use of hydrogen as the carrier gas is a good choice to shorten runtimes and improve the chromatographic resolution, while tandem mass spectrometry is a well-known alternative for this analysis. All the chromatographic and mass spectrometric parameters fill the requirements of the reference methods with a 35% reduction of runtimes. The accuracy is tested with three fly ash samples of a proficiency interlaboratory test. A good correlation between the results is obtained ( R2 = 0.992, slope = 0.9675), and no coelutions are noted. The system robustness is tested during 5 years of constant use and the maximal relative standard deviation of the relative response factor is 18.8%. [ABSTRACT FROM AUTHOR]

Indoor aerosol sources may significantly contribute to the daily dose of particles deposited into the human respiratory system. Therefore, it is important to characterize the aerosols deriving from the operations currently performed in an indoor environment and also to estimate the relevant particle respiratory doses. For this aim, aerosols from indoor combustive and non-combustive sources were characterized in terms of aerosol size distributions, and the relevant deposition doses were estimated as a function of time, particle diameter and deposition site in the respiratory system. Ultrafine particles almost entirely made up the doses estimated. The maximum contribution was due to particles deposited in the alveolar region between the 18th and the 21st airway generation. When cooking operations were performed, respiratory doses per unit time were about ten-fold higher than the relevant indoor background dose. Such doses were even higher than those associated with outdoor traffic aerosol. [ABSTRACT FROM AUTHOR]

• Determination of 22 PAHs in honey samples by DLLME-GC–MS. • Chemometric approach for identifying the main PAHs responsible of contamination. • Comparison with similar database for evidencing the contamination sources. • Chemometrics for tracing the food quality based on the production area. The quality of honey is assessed through the determination of some commodity parameters: a certain importance is to be attributed to the absence of contaminating residues, in particular of Polycyclic Aromatic Hydrocarbons (PAHs). This paper deeply investigates the presence of 22 PAHs in 57 honey samples collected in Central Italy and identifies the possible source apportionment and fingerprint identification by DLLME-GC–MS analysis and a chemometric approach. Cluster Analysis and Principal Component Analysis have allowed to identify the main PAHs responsible of the contamination, benzo[ a ]anthracene and phenanthrene, characteristics pollutants of areas constantly exposed. The entire database has been compared to similar ones present in literature, particularly data from Serbia and Belgrado samples. The PCA applied to overall the data confirms the combustion to be the main contamination source in Italian samples whereas highlights the importance of the role of naphthalene, added during beekeeping practices in the other data-set. [ABSTRACT FROM AUTHOR]

Emissions from biomass combustion depend on biomass characteristics, operating parameters and concern different types of compounds such as: CO 2 , CO, SO 2 , NO X , inorganic and organic micro-pollutants, polyciclic aromatic hydrocarbons, polychlorinated byphenils, and particulate matter. The aim of this work is the development of a fixed source sampling method for total levoglucosan emission, commonly considered, along with its isomer mannosan and galactosan as an atmosphere tracers for Total Suspended Particles generated by biomass burning. The semi-volatile behavior of such compound was taken into account and its sampling occurred by depositing the main fraction on a filter and the volatile fraction sampled by impingers filled with specific solution. Subsequently, the emission factors of levoglucosan in Total Suspended Particles from burning of rice and wheat straw varying from 53.7 to 65.8 mg/kg fuel were evaluated. The proposed method uses an isokinetic probe with quartz filter for particle fraction sampling and a system of impingers for the volatile fraction. The important result obtained from the experiment showed that a percentage between 30% and 50% of levoglucosan exceeds the filter and was sampled in the impingers. This result suggests the importance to collect both fractions of levoglucosan emission in order to not neglect the volatile fraction which represents an important component and must not be omitted. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: This study investigates the removal efficiency of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) by the APCDs of an iron ore sintering plant, an electrostatic precipitator (ESP) and a wetfine scrubbing system (WS). The removal efficiencies of the ESP on the total PCDD/Fs concentration and the total PCDD/Fs I-TEQ concentration are 44.3% and 41.4%, respectively, while those of the WS are 66.7% and 68.4%, respectively, but the vapor/solid phase distribution changes after APCDs abatement. At ESP inlet, the PCDD/Fs account for 31.2% in vapor phase and for 68.8% in particulate phase while, at ESP outlet, the PCDD/Fs account for 63.3% in vapor phase and for 36.7% in solid phase. The ESP removes effectively solid-phase PCDD/Fs for its effectiveness to capture the particulate while it is ineffective in removing vapor-phase PCDD/Fs. It, on the contrary, increase for the vaporization within the ESP, especially for these congeners with a lower chlorination degree, and for the PCDD/Fs “stripping” from particulate to gas-phase during the sampling. At WS inlet, the PCDD/Fs account for 63.3% in vapor phase and for 36.7% in solid phase while, at WS outlet, the PCDD/Fs account for 21.4% in vapor phase and for 78.6% in solid phase. Considering that WS outlet temperature is about 40°C, the PCDD/Fs vapor-phase condense to particles: therefore, even if the particulate is removed by WS, the final result is that PCDD/Fs percentage decreases in vapor-phase and increases in solid-phase. [Copyright &y& Elsevier]

This study investigated the influence of different charge typologies and additives on the PCDD/Fs amount produced and on the congener profiles in an iron ore sintering plant. Many tests were carried out combining different typologies of charge (iron materials) and solid fuel (“coke breeze” or “anthracite”) with or without the use of urea. The PCDD/Fs produced ranged from 1.2 to 22.7 μg I-TEQ/ton of agglomerate, whereas the PCDD/Fs released to the ambient air ranged from 0.10 to 1.92 ng I-TEQ/Nm3 because of cleaning in an electrostatic precipitator (ESP) and a Wetfine scrubber (WS). A more homogeneous charge with a higher amount of fine particles charge appeared to produce a lower PCDD/Fs concentration due to a better combustion but this hypothesis needs further investigations on charges having different dimension particles. Only a synergitic action of urea and anthracite was able to reduce the high PCDD/Fs content due to the bad combustion of the more inhomogeneous charge with a lower amount of fine particles. The congener profile was a typical combustion process fingerprint because the PCDFs predominated, the highly chlorinated congeners (HeptaCDD and OctaCDD) prevailed in PCDDs, whereas in PCDFs the profile was more varied; 1,2,3,4,6,7,8-HeptaCDF was the main contributor to the total concentration while 2,3,4,7,8-PentaCDF was the main contributor to the I-TEQ concentration. Whereas all the parameters under scrutiny influenced strongly the amount of PCDD/Fs produced, they affected only slightly the fingerprint of PCDD/Fs. In all cases studied, the reduction obtained using urea, anthracite, or the more homogeneous charge with a higher amount of fine particles was slightly greater on the higher chlorinated congeners in respect to the lower ones. [ABSTRACT FROM AUTHOR]

Active carbon-based sorbents are well known and are used in analytical chemistry. Activated carbon fibers (ACFs) are mainly used as abatement systems in industrial emission pollution control. The objective of this study was to extend the use of ACFs in analytical chemistry for the analysis of polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), dioxin-like polychlorobiphenyls (PCBs), and chlorobenzenes (CBs). For this purpose, the extraction efficiency was evaluated based on the QA/QC criteria defined by EPA/ISO reference methods on 13C-standards recovery rates. The procedures tested were ultrasonic assisted extraction (UAE), Soxhlet extraction (SE), accelerated solvent extraction (ASE), and microwave-assisted extraction (MAE). Each experiment was performed in triplicate to ensure the repeatability of the results, and a second extraction assessed the complete extraction. The comparison of the results of each set of experiments with the minimum requirements of the reference methods for each class of compounds led to SE being chosen as the best technique. SE with toluene resulted in a reduction of time and costs and with respect to the other investigated techniques. The present work demonstrated that ACFs can be used in environmental fields means of both prevention and control (exploiting the adsorbent characteristics) and for analytical purposes (exploiting the desorption) for the described chlorinated classes of pollutants. [ABSTRACT FROM AUTHOR]

A monitoring campaign of polychlorinated dibenzop- dioxins and dibenzofurans, polyaromatic hydrocarbons (PAHs), and polychlorinated biphenyl was carried out in an Italian iron ore sintering plant by sampling the combustion gases at the electrostatic precipitator (ESP) outlet, at the Wetfine scrubber (WS) outlet, and by collecting the ESP dust. Few data are available on these micropollutants produced in iron ore sintering plants, particularly from Italian plants. This study investigates the PAH emission profiles and the removal efficiency of ESPs and WS. PAHs were determined at the stack, ESP outlet flue gases, and in ESP dust to characterize the emission profiles and the performance of the ESP and the WS for reducing PAH emission. The 11 PAHs monitored are listed in the Italian legislative decree 152/2006. The mean total PAH sum concentration in the stack flue gases is 3.96 μg/N · m3, in ESP outlet flue gases is 9.73 μg/N · m3, and in ESP dust is 0.53 μg/g. Regarding the emission profiles, the most abundant compound is benzo(b)fluoranthene, which has a relative low BaP toxic equivalency factors (TEF) value, followed by dibenzo(a,l)pyrene, which has a very high BaP(TEF) value. The emission profiles in ESP dust and in the flue gases after the ESP show some changes, whereas the fingerprint in ESP and stack flue gases is very similar. The removal efficiency of the ESP and of WS on the total PAH concentration is 5.2 and 59.5%, respectively. [ABSTRACT FROM AUTHOR]

Due to the increasing tattoo practicing in Eastern countries and general concern on tattoo ink composition and safety, the green tattoo inks Green Concentrate by Eternal, for European and "for Asia Market Only" were analyzed, under the premise that only the former falls under a composition regulation. A separation of the additives from the pigment was carried out by successive extraction in solvents of different polarities, i.e., water, acetone and dichloromethane. The solid residues were analyzed by IR and Raman spectroscopies, the liquid fractions by GC/mass spectrometry. The relative pigment load and element traces were also estimated. We found that the European and the Asian inks are based on the same pigment, PG7, restricted in Europe, though at different loads. They have a similar content of harmful impurities, such as Ni, As, Cd and Sb and both contain siloxanes, including harmful D4. Furthermore, they have different physical-chemical properties, the European ink being more hydrophilic, the Asian more hydrophobic. Additionally, the Asian ink contains harmful additives for the solubilization of hydrophobic matrices and by-products of the phthalocyanine synthesis. Teratogenic phthalates are present as well as chlorinated teratogenic and carcinogenic compounds usually associated to the laser treatment for removal purposes, to a larger extent in the European ink. The composition of the inks does not seem to reflect regulatory restrictions, where issued. [ABSTRACT FROM AUTHOR]

The tattoos removal has become an issue upon spread of the tattooing practice worldwide and hindsight regrets. Lasers are typically used for the purpose, though some colours such as green are considered "recalcitrant" to the treatment. In the current investigation, we aim at determining the efficacy of removal of a green ink water dispersion, using 5 laser treatments: Nd:YAG nano- and picosecond lasers in normal and array mode and Ruby nanosecond laser, keeping the total irradiated energy constant. The UV–Vis spectroscopy of the treated samples indicate that Nd:YAG picosecond laser is most effective, and the Ruby nanosecond laser is the least efficient. Fragment compounds generated from the pigment and siloxanes are common to all treatments, whereas hydrocarbon emerge by a larger amount upon Nd:YAG nanosecond treatment. Fibres are formed upon picosecond treatments and when operating in array mode, and lamellae are achieved by Ruby nanosecond laser treatment. Residual particles suspensions are very heterogeneous upon nanosecond treatments. [ABSTRACT FROM AUTHOR]

Comparative laser and thermal treatments were carried out on PG36, a green phthalocyanine-based pigment, permitted in European countries where legislation on tattoo composition was issued. Prior to the treatments, PG36 was characterized by SEM imaging, EDX, IR and UV–Vis spectroscopies, revealing an excess of Si and C and O as compared to the pure halogenated Cu-phthalocyanine. Laser treatments were carried out with a Nd:YAG device applied to H2O and propan-2-ol dispersions. Pyrolysis and calcinations were carried out in air or under N2 flow. The outcome of the different procedures was analyzed by UV–Vis spectroscopy, GC–mass spectrometry, X-ray diffraction of the solid residues, SEM microscopy and dynamic light scattering. The comparative analysis indicated the production of different fragment compounds depending on the treatment, (pyrolysis or laser), and, to some extent, to the solvent of the dispersion, with pyrolysis generating a larger number of hazardous compounds. Hydrocarbons and cyclic siloxanes present as additives in PG36 were stable or degraded depending on the treatment. The morphology of the products is also treatment-dependent with nanoparticles < 20 nm and fibers being produced upon laser treatments only. Based on the experimental findings, the equivalence of laser and thermal treatments is evaluated. [ABSTRACT FROM AUTHOR]

The need to use renewable sources and matrices with energy potential is widely recognized. The development of innovative technologies aimed at the improvement of energy conversion processes and reducing environmental impacts is currently receiving increasing attention from the scientific community and policymakers. The presence of sugars in airborne particle materials is attributed to biomass combustion. For this reason, these compounds are considered markers of biomass burning. The purpose of this work was to evaluate the emissions produced by agroforestry biomass burning (citrus pruning) by simultaneously sampling both stack emissions and atmospheric particulates in the area around a biomass boiler to understand the real contribution of biomass burning to atmospheric pollution. The combustion tests were carried out by comparing the processes with and without particulate abatement system to see how biomass combustion's contribution to particulate emission can be controlled and reduced. During the tests, the focus was on particulate matter (PM) speciation in terms of sugar marker identification and determination. This study aims to increase knowledge to better understand the contribution of biomass plants to air pollution and differentiate it from the contributions of other sources, such as vehicular traffic or domestic heating. [ABSTRACT FROM AUTHOR]

Forestry woodchip and spent mushroom compost have commercial potential as sustainable residues in biological and chemical processes for energy production. This study focuses on the evaluation of agri-food industry waste energy valorization, with the aim to reduce the valuable biomass utilization for energy production without decreasing the process quality, thereby pursuing economic and environmental advantages. Burning trials were conducted in a fluidized bed biomass plant provided with emission abatement systems. The biomass mixture used for combustion was composed of pine and oak woodchip and spent mushroom compost. The biomass used was first characterized through compositional and energetic analysis, and subsequently, during the burning tests, a monitoring sampling campaign was carried out to analyze the gas and particles emission. Optimal combustion conditions were observed during combustion, with good oxidation of the organic material, relatively high CO2 production, and low CO concentration in flue gas. Nevertheless, SO2 concentrations in the combustion flue gas are greater than those found in the combustion of the most commonly used biomasses. In fact, the mixture compositional characterization revealed a non-negligible concentration of sulfur, which explains the high values of SO2 detected in emission. The obtained results confirm that controlled combustion, together with suitable biomasses utilization, preliminary characterization, and emission monitoring, are essential practices for the realization of a sustainable process, both from an energy and environmental point of view. [ABSTRACT FROM AUTHOR]

Agricultural activities lead to the production of large quantities of pruning and residual biomass, the correct disposal of which is a topic of great interest. Unfortunately, although it is an environmentally unacceptable practice, disposal often takes place with uncontrolled combustion in field (open burning). Disposal using biomass boilers produces energy from controlled combustion and the use of abatement systems reduces emissions that are inevitably generated in the combustion processes of solid fuel (CO, CO2, NOx, SO2, PM, etc.). Among the pollutants produced in combustion processes, Persistent Organic Pollutants (POPs) are one of the most relevant groups of chemicals that must be monitored for their effect on human health and the environment. This paper reports the data obtained for the emissive characterization of POPs of three different wood biomass prunings (Olive, Citrus and Grapevine) focusing on VOCs, PAHs, PCBs, PCDD/Fs. Emissions samplings were performed at the stack during combustion in a 30 kWth boiler equipped with a multicyclone filter bag for PM abatement in an isokinetic mode in accordance with the CEN and ISO standards methods. Through this work, a complete emission profile of VOCs, PAHs, PCBs, and PCDD/Fs of three different biomass types is provided for the first time, showing that the use of biomass boilers produces quantities of pollutants below the regulatory limits and still lower than those produced by open burning phenomena. Citrus has shown, regarding the other two essences, elevated concentrations in terms of Σ PAH = 174.247 ng/m3, while Olive gave higher results in terms of PCBs and PCDD/Fs (respectively, 39.769 and 3390.63 TEQ pg/Nm3). This is probably due to the high concentration of iron in this biomass (711.44 mg/kg), which during combustion is a catalyst (together with copper) of PCDD/Fs. [ABSTRACT FROM AUTHOR]

Cement plants are responsible for particle and gaseous emissions into the atmosphere. With respect to particle emission, the greater part of is in the range from 0.05 to 5.0 µm in diameter. In the last years attention was paid to submicron particles, but there is a lack of available data on the emission from stationary sources. In this paper, concentration and size distribution of particles emitted from four cement kilns, in relationship to operational conditions (especially the use of alternative fuel to coal) of the clinker process are reported. Experimental campaigns were carried out by measuring particles concentration and size distribution at the stack of four cement plants through condensation particle counter (CPC) and scanning mobility particle sizer spectrometer (SMPS). Average total particle number concentrations were between 2000 and 4000 particles/cm3, about 8–10 times lower that those found in the corresponding surrounding areas. As for size distribution, for all the investigated plants it is stable with a unimodal distribution (120–150 nm), independent from the fuel used. Implications: The study provides information on submicron particles emitted from cement kilns in different driving conditions. In particular, the total particle number is modest and considerably lower than that measured in ambient air, whereas the particle size distribution could be influenced by the operational conditions. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) is the third most important greenhouse gas after carbon dioxide and methane, and contributes about 6% to the greenhouse effect. Nitrous oxide is a minor component of the atmosphere, and it is a thousand times less than carbon dioxide (CO2). Nevertheless, it is much more potent than CO2and methane, owing to its long stay in the atmosphere of approximately 120 yr and the high global warming potential (GWP) of 298 times that of CO2. Although greenhouse gases are natural in the atmosphere, human activities have changed the atmospheric concentrations. Most of the values of emission of nitrous oxide are still obtained by means of emission factors and not actually measured; the lack of real data may result in an underestimation of current emissions. The emission factors used for the calculation of N2O can be obtained from the “Guidelines for the implementation of the national inventory of emissions” of the Intergovernmental Panel on Climate Change, which refer to all nations for the realization of their inventory. This study will present real data, measured in several Italian cement plants with different characteristics. The work also shows a comparison between N2O concentration measured with in situ Fourier transform IR (FTIR) and the reference method EN ISO 21258 based on nondispersive IR (NDIR), in order to investigate the interfering compounds in the measurement with NDIR.Implications:N2O may arise as an unwanted by-product of nitrogen oxide (NOx) abatement systems, in particular selective noncatalytic reduction (SNCR). Since it is applied in the cement plants, N2O emission from cement industry is evaluated, with both FTIR and NDIR instrument. Several considerations emerged from the results. First of all, the emission from this industrial sector is not negligible, and for that reason N2O concentration should be regulated; another observation is that the reference method based on the NDIR technique is not as selective as FTIR could be. [ABSTRACT FROM PUBLISHER]

Abstract: Although the worldwide presence of illicit psychotropic compounds in the environment is well known, the social impact of drug abuse on the community has yet to be determined. Besides, the possibility of deriving indicators of the prevalence of drug abuse from the content of illicit substances in the air remains unexplored. In this study, the atmospheric concentrations of psychotropic compounds recorded in Italy were plotted vs. a series of criminal statistics. Meaningful links were found between atmospheric cocaine and the amount of drugs seized, the number of drug related crimes and the demand for clinical treatment recorded in the Italian regions. Atmospheric cocaine and cannabinoids also seemed to be correlated with tumour insurgence and mental disease frequency, respectively. However, further investigations are necessary to elucidate/explain/clarify if the behaviours observed for cocaine vs. the parameters usually adopted to estimate drug abuse prevalence (correspond to an effective relationships)/are directly linked, and to understand why the same approach failed when applied to cannabinoids. Moreover, according to our study illicit drugs are suspected to promote long-term ill health effects even when present at low concentrations the air. [Copyright &y& Elsevier]

The factors affecting polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) formation were studied in sewage sludge incineration tests carried out on a demonstrative plant. The plant includes a circulating fluidised bed furnace (FBF) and a rotary kiln furnace (RKF), operating alternatively. During the tests sewage sludge was spiked with chlorinated hydrocarbons and the operating parameters of the afterburning chamber were varied. PCDD/F were sampled in each test before the bag filter, thus collecting the above contaminants before abatement systems.From the tests it appeared that PCDD/F were always produced in more abundance in the tests carried out by FBF than by RKF. The higher PCDD/F concentrations in the tests by FBF were reached when sewage sludge was spiked with a high dosage of a surrogate organic mixture of chlorinated hydrocarbons and when the afterburning chamber was used only as transit equipment with the burner off.The distribution of the different PCDD/F homologues was compared. P5CDFs were generally the prevalent fraction, with very few exceptions for the tests by RKF at high temperature of the afterburning chamber. As for FBF tests, it was found that the PCDD/F homologue profile depends on the afterburning chamber temperature. [Copyright &y& Elsevier]

Three cases are reviewed of radioactive material with anomalous decay after ultrasound irradiation. In the pure element thorium-228 in distilled water, the radioactivity decreased faster after cavitation than the natural decay. The more complex molecule of Nickel Nitrate, made of radioactive nickel-63, in solution of nitric acid and distilled water was investigated before and after ultrasound irradiation. The X-rays produced by Bremsstrahlung of the electrons from the beta decay of Ni-63 were recorded and a 13% decrease of intensity was measured after 100 s of sonication. A decrease of nickel and an increase of other elements was detected by mass spectrometry in the sonicated sample. The Cobalt-57 decay was investigated by detecting the gamma and X-ray intensity from the Iron-57 resulting after its beta emission. In this third case too, an anomalous decay was observed after sonication. These three cases of anomalous behavior can be explained at the light of the Deformed Space–Time theory. It assumes that a suitable sudden variation of energy density can induce a local deformation of space–time, thus violating the Local Lorentz Invariance. This variation can be created by the ultrasounds in the matter, thus, allowing reactions that cannot occur in a flat (Minkowskian) space–time. The "neutralization" of a radionuclide occurs when it undergoes a DST transformation changing the radionuclide into non-radioactive nuclides. [ABSTRACT FROM AUTHOR]

Ammonia is a common factor linking air in bat caves and air pollution in the proximity of agricultural fields treated with livestock farming sewage and slaughterhouses, where important clusters of COVID-19 have recently been reported all over the world. Such a commonality has a further connection with the known behavior of some viruses of the coronavirus family, such as the murine hepatitis virus, whose spike glycoprotein (S) can be triggered to a membrane-binding conformation at pH 8.0. Within the airborne route of virus transmission, with particular relevance for crowded and enclosed environments, these observations have prompted a hypothesis that may represent a contributing cause to interpret the geographical variability of the virus diffusion and the surging rise of COVID-19 cases in slaughterhouses all over the world. The hypothesis is that, in these environments, the SARS-CoV-2 S protein may find on a fraction of the airborne particles an alkaline pH, favorable to trigger the conformational changes, needed to induce the fusion of the viral envelope with the plasma membrane of the target cells. [ABSTRACT FROM AUTHOR]

• Industrial polyethylene waste was co-combusted with rice husk in a 4MW thermal power plant. • Concentrations of PCBs, PCDD/Fs, PAHs and PM have remained almost unaffected by introducing polyethylene in feed. • The emissions factors of the organic micropollutants are lower with polyethylene increasing rate. • Polyethylene waste with low content in halides and metals can be energetically recycled. • An environmental sustainable solution at the plastic waste management challenge is proposed. Co-combustion of biomass and plastic waste has emerged as one of the most promising approach at the plastic waste management challenge. This strategy is particularly attractive since it can simultaneously solve the increasing energy demand and reduce the plastic wastes volume. However, since the combustion of both plastic wastes and natural materials is a potential source of organic micropollutants, such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and of polycyclic aromatic hydrocarbons (PAHs), beside particulate matter, the environmental sustainability of the waste to energy (WtE) co-combustion strategy has to be assessed. To this end, the emissions of dioxin like (dl)-PCBs, PCDD/Fs and PAHs from a 4-MW thermal power plant fueled with rice husk, partially replaced by end-of-life polyethylene (PE) industrial waste (up to 15% of the thermal power of the plant), were investigated. GC-MS/MS analyses have demonstrated that the co-combustion of PE waste and rice husk presents a profile of environmental sustainability. The concentrations of dl-PCBs, PCDD/Fs and PAHs were extremely low and they have remained almost unaffected by introducing PE in feed. In particular, emissions of PCCD/Fs and dl-PCBs in flue gas were in the range 0.6–1.0 and 0.2–0.6 pg TEQ/Nm3, respectively, while PAHs concentrations ranged from 410 to 825 ng/Nm3. Furthermore, the emission factors of these organic pollutants were found to be lower with PE increasing rate while particulate matter emissions were not affected by co-combustions. Collectively, the investigation has demonstrated that the noils of the industrial PE, due to the low content in halides and metals, can be used as auxiliary fuel and energetically recycled through co-combustion with rice husk. This case of study represents an effective application of the WtE strategy and a concrete approach to mitigate the threat of plastic pollution. [ABSTRACT FROM AUTHOR]

The radioactivity reduction of a system containing Ni-63 radioactive nuclei after an appropriate ultrasound treatment in an apparatus designed on purpose is reported. The application of ultrasounds for 200 s resulted in the partial disappearance of about 13% of the radioactive Ni-63 nuclei and the appearance of nonradioactive elements. The formation of new elements, not belonging to the decay chain of Nickel-63, is a strong issue where strong nuclear reactions transform Nickel into different elements rather than the usual weak interaction, responsible for the decay, which is accelerated. This way, the time necessary to halve the intensity is shortened by about 20 years, without altering the Ni-63 decay constant, which is 1 4 6. 0 0 ± 2. 1 6  years. Two cases producing similar effects in other radioactive systems after ultrasound treatment are described in the literature and support this finding, which is not forecast by the commonly accepted theories. A theory able to explain these and other results is also reported. [ABSTRACT FROM AUTHOR]

Laboratory and field studies were carried out to assess the effects of oxidative degradation and volatilization on PM 10 bound polycyclic aromatic hydrocarbons (PAHs), collected at low volume condition according to the EU sampling reference method EN12341:2014 (flow rate 2.3 m 3  h −1 ), on 47 mm quartz filters. For the laboratory experiments, pairs of twin samples were collected in field and, after treatments favoring decomposition or/and volatilization of PAHs on one sample, the PAH amount was compared with that of the corresponding untreated sample. Ozone exposure caused a general PAHs decay with more marked effects on benzo [ a ]pyrene, perylene and benz [ a ]anthracene; these compounds showed, similarly to benzo [ghi]perylene, correlations between ozone dose and losses. Treatments with zero air exhibited losses due to volatilization even for 5-ring PAHs up to benzo [ a ]pyrene, whereas a linear dependence was observed between filter PAH load and losses for benzo [ a ]anthracene, chrysene and benzofluoranthenes. Concentrations on samples collected simultaneously over 48, 24, 12 and 6 h were compared. Results confirmed a lack of temporal auto-consistency in the PAHs sampling methodology here adopted. In particular higher atmospheric PAH concentrations were ascertained on samples constituted by cumulative filters exposed over shorter sampling times. When 24–h and 2 × 12-h samples were compared, comparable losses were evaluated in the hot and cold seasons. This finding shows that, although in summer meteorology conditions favor sampling artifacts, the effectiveness of these phenomena continue in the winter, probably due to the larger amount of PAH available on the sampling filter (total PAHs ∼ 10 vs 0.5 ng m −3 ). [ABSTRACT FROM AUTHOR]

The artifacts induced by oxidative degradation and volatilization were assessed with regards to determination of particulate atmospheric PAHs collected at low volume conditions (2.3 m 3 h −1 ) according to the EU Reference Method EN 12341:2014. In order to evaluate the oxidative degradation, PAH measures carried out through collecting airborne particulate with and without ozone denuders were examined. Simultaneously, the influence of volatilization was investigated by comparing concentrations of PAHs in particulate samples collected over 24-h and 12-h using conventional instruments. Summer and winter/spring campaigns were carried out in order to assess the influence of environmental contour on the artifact processes. Oxidative degradation led to a general decrease of PAH concentrations in both periods; in particular, the highest losses were observed for benzo[ a ]pyrene and perylene reaching, in average, ca. 20%. In the summer, the effect of volatilization exceeded that of oxidative degradation for light PAHs up to benzo[e]pyrene. In the winter/spring time, the influence of both artifact typologies could be mitigated by splitting the normal 24-h collection interval starting at midnight into two 12-h intervals. A mitigation of the losses could even be obtained by fixing the start time sampling fixed at noon or in the first hours of the day. Finally, the feasibility of collecting PAHs through prolonged sampling (>1 month) at the flow rate of 1.1 L min −1 was preliminarily investigated. Results indicated that this approach is unsuitable for minimizing the oxidative artifacts. [ABSTRACT FROM AUTHOR]

The combustion of biomass is a process that is increasingly used for the generation of heat and energy through different types of wood and agricultural waste. The emissions generated by the combustion of biomass include different kinds of macro- and micropollutants whose formation and concentration varies according to the physical and chemical characteristics of the biomass, the combustion conditions, the plants, and the operational parameters of the process. The aim of this work is to evaluate the effect of biomass moisture content on the formation of volatile organic compounds (VOCs) during the combustion process. Wet and dry poplar chips, with a moisture content of 43.30% and 15.00%, respectively, were used in a cogeneration plant based on a mobile grate furnace. Stack's emissions were sampled through adsorbent tubes and subsequently analyzed by thermal desorption coupled with the GC/MS. The data obtained showed that, depending on the moisture content of the starting matrix, which inevitably influences the quality of combustion, there is significant variation in the production of VOCs. [ABSTRACT FROM AUTHOR]

[Display omitted] Magnetite (Fe 3 O 4) nano-particles (M NPs) have been found in human tissues and causally linked to serious illnesses. The possible negative role of MNPs has been not still fully ascertained even though MNPs might cause health effects due to their magnetic property, redox activity and surface charge. The origin of MNPs in human tissues still remains to be unambiguously identified since biological processes, natural phenomena and anthropogenic production have been proposed. According to this latter increasingly convincing hypothesis, anthropogenic MNPs might enter mainly in the human body via inhalation, penetrate deeply into the lungs and in the alveoli and also migrate into the blood circulation and gather in the extrapulmonary organs and central nervous system. In order to identify the releasing source of the potentially inhalable MNPs, we pioneered an innovative approach to rapidly investigate elemental profile and morphology of a large number of airborne micron and sub-micron-sized Fe-bearing particles (FePs). The study was performed by collecting a large amount of micron and sub-micron sized inhalable airborne FePs in trafficked and densely frequented areas of Rome (Italy). Then, we have investigated individually the elemental profile and morphology of the collected particles by means of high-spatial resolution scanning electron microscopy, energy dispersive spectroscopy and an automated software purposely developed for the metal-bearing particles analysis. On the basis of specific elemental tracing features, the investigation reveals that almost the total amount of the airborne FePs is released by the vehicle braking systems mainly in the form of magnetite. Furthermore, we point out that our approach might be more generally used to identify the releasing sources of different inorganic airborne particles and to contribute to establish more accurately the impact of specific natural or anthropogenic particles on the environment and human health. [ABSTRACT FROM AUTHOR]

An experimental campaign was carried out on a hospital and cemetery waste incineration plant in order to assess the emissions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polycyclic aromatic hydrocarbons (PAHs). Raw gases were sampled in the afterburning chamber, using a specifically designed device, after the heat recovery section and at the stack. Samples of slags from the combustion chamber and fly ashes from the bag filter were also collected and analyzed. PCDD/Fs and PAHs concentrations in exhaust gas after the heat exchanger (200–350°C) decreased in comparison with the values detected in the afterburning chamber. Pollutant mass balance regarding the heat exchanger did not confirm literature findings about the de novo synthesis of PCDD/Fs in the heat exchange process. In spite of a consistent reduction of PCDD/Fs in the flue gas treatment system (from 77% up to 98%), the limit of 0.1ngITEQNm−3 at the stack was not accomplished. PCDD/Fs emission factors for air spanned from 2.3 up to 44μgITEQt−1 of burned waste, whereas those through solid residues (mainly fly ashes) were in the range 41–3700μgITEQt−1. Tests run with cemetery wastes generally showed lower PCDD/F emission factors than those with hospital wastes. PAH total emission factors (91–414μgkg−1 of burned waste) were in the range of values reported for incineration of municipal and industrial wastes. In spite of the observed release from the scrubber, carcinogenic PAHs concentrations at the stack (0.018–0.5μgNm−3) were below the Italian limit of 10μgNm−3. [Copyright &y& Elsevier]

• Combustion tests were performed in a small-size biomass boiler to assess the air quality during biomass burning. • Biomass characterization and modeling of yields and emissions in combustion. • Evaluation of woodfuel parameters useful to sustainable practices, highest energetic yields and lowest environmental impacts. • Olive residues represents the most advantageous biomass, in terms of emissions and energy yield. • Grapevine and citrus residues showed high N content and consequent high NO x production. The increased interest in using farm-grown biomass for energy production makes it necessary to expand and deepen knowledge on combustion of agricultural residues. The lack of data and studies on solid fuel quality, and combustion related emissions, represents an obstacle to the sustainable development of agricultural biomass industry. In the Mediterranean basin, large quantities of lignocellulosic biomass are obtained yearly from pruning operations carried out largely widespread in fruit plantations such as citrus, grapevine and olive orchards. The most common practice to eliminate this type of residue is the open burning, carried out directly on the field by farmers, without any emissions control or energy recovery. The aim of this study was to obtain a clear description of three different wood biomasses and their behavior during combustion. The physicochemical properties were studied to determine their influence on combustion emissions. Measurements were conducted in laboratory and subsequently carbon monoxide (CO), carbon dioxide (CO 2), oxygen (O 2), nitrogen oxides (NO x), sulfur dioxide (SO 2), Total Organic Compounds (TOC), and particulate matter (PM) emissions were evaluated during combustion in a 30 kW boiler equipped with a multicyclone filter bags for emission abatement. Principal Component Analysis (PCA) was applied to the data of biomass properties and emissions parameters in order to elucidate which feedstock features had a more determinant influence on the combustion process. Grapevine and citrus showed high N content and consequent high NO x production. Olive highlighted the best characteristics, high energetic potential and low emissions under regulation limits; in addition, olive pruning residues is the most available woodfuel in the Mediterranean area of Europe, confirming its great potential on agricultural biomass industry sustainable development. [ABSTRACT FROM AUTHOR]

Asbestos containing materials (ACMs) are currently landfilled or encapsulated, but this may lead to the release of fibres in the environment. Hence, the destruction of asbestos containing waste (ACW) is now regarded as a preferable option. Thermal treatments based on chrysotile and amphibole asbestos dehydroxylation and recrystallization are being successfully developed for this purpose. This study investigates the emission of asbestos fibres from a prototype for asbestos treatment. Other atmospheric pollutants measured include carbon monoxide (CO), nitrogen oxides (NO x), sulfur dioxide (SO 2), volatile organic compounds (VOCs), heavy metals, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) dioxins and furans (PCDD/Fs). Both cement-asbestos and ACM containing polyurethane were tested. No asbestos fibres were found, neither in the emission nor in the solid residue. The concentration of NO x , SO 2 and heavy metals are comparable with municipal solid waste incinerators (MSWI) and cement plants. PAHs, BTEX (benzene, toluene, ethylbenzene, xylenes) and styrene are higher in the presence of polyurethane. The presence of polyvinyl chloride (PVC) in the coating of asbestos cement can increase the emission of halogenated VOCs, PCBs and PCDD/Fs. Our results confirm that asbestos inertisation is a safe process for the environment and human health, and economically competitive with landfills. Image 1 • First measurement of atmospheric pollutants emitted from ACW treatment. • Experimental evidence that no asbestos fibres are emitted in the atmosphere. • Chrysotile dehydroxylation/recrystallization in byproduct and emitted particles. • PAHs and BTEX mainly due to polyurethane and other non-asbestos components of ACW. • PVC in ACW coating promotes the emission of dioxins and halogenated VOCs. [ABSTRACT FROM AUTHOR]

• 2367-TeCBP is crucial in the determination of the risk assessment in cases of fires. • 2,3,6,7-TeCBP concentration was remarkably higher than that of the 2,3,7,8-TeCDD. • 2367-TeCBP was found to be a persistent micro-organic pollutant. It is known that when fires or explosions involve electrical systems, along with PCDDs and PCDFs, polychlorinated biphenylenes (PCBPs) are also produced. These chlorinated tricyclic aromatic pollutants were noticed in fire rubbles and after the World Trade Center destruction. However, the analytical difficulties in developing an efficient method have limited the knowledge of their environmental distribution. In light of the equipotency of 2,3,6,7-TeCBP and 2,3,7,8-TeCDD, PCBPs call for more accurate investigations. In this paper, for the first time, the level and persistence of 2,3,6,7-TeCBP have been investigated in air samples (both indoor and outdoor) after a fire broke out in an industrial building. GC–MS/MS analysis revealed that 2,3,6,7-TeCBP concentrations after the fire (3046 fg/m3 at the "epicentre") were remarkably higher than that of the 2,3,7,8-TeCDD. Moreover, the monitoring for over two years has demonstrated the persistent nature of this compound. 2,3,6,7-TeCBP was also analyzed in two different ambient air scenario: industrial and periurban areas and in both cases its concentrations were no matter of concern, confirming the correlation of 2,3,6,7-TeCBP with fire episodes. Collectively, 2,3,6,7-TeCBP, because of its toxicity, concentration and persistence, is a crucial compound in the evaluation of the health effects correlated with fires of electrical systems. [ABSTRACT FROM AUTHOR]

Drying is a critical point for the exploitation of biomass for energy production. High moisture content negatively affects the efficiency of power generation in combustion and gasification systems. Different types of dryers are available however; it is known that rotary dryers have low cost of maintenance and consume 15% and 30% less in terms of specific energy. The study analyzed the drying process of woody residues using a new prototype of mobile rotary dryer cocurrent flow. Woodchip of poplar (Populus spp.), black locust (Robinia pseudoacacia L.), and grapevine (Vitis vinifera L.) pruning were dried in a rotary drier. The drying cycle lasted 8 h for poplar, 6 h for black locust, and 6 h for pruning of grapevine. The initial biomass had a moisture content of around 50% for the poplar and around 30% for grapevine and black locust. The study showed that some characteristics of the biomass (e.g., initial moisture content, particle size distribution, bulk density) influence the technical parameters (i.e., airflow temperature, rate, and speed) of the drying process and, hence, the energy demand. At the end of the drying process, 17% of water was removed for poplar wood chips and 31% for grapevine and black locust wood chips. To achieve this, result the three-biomass required 1.61 (poplar), 0.86 (grapevine), and 1.12 MJ kgdry solids−1 (black locust), with an efficiency of thermal drying (η) respectively of 37%, 12%, and 27%. In the future, the results obtained suggest an increase in the efficiency of the thermal insulation of the mobile dryer, and the application of the mobile dryer in a small farm, for the recovery of exhaust gases from thermal power plants. [ABSTRACT FROM AUTHOR]