Search Results (3,071)

Unlike stratospheric ozone (O₃), which is beneficial for Earth due to its capacity to screen the surface from solar ultraviolet radiation, tropospheric ozone poses a number of health and environmental issues. It has multiple effects that drive anthropogenic climate change, ranging from pure radiative forcing to a reduction of carbon sequestration potential in plants. In the central Mediterranean, which itself represents a hotspot for climate studies, multi-year data on surface ozone were analyzed at the Lamezia Terme (LMT) WMO/GAW coastal observation site, located in Calabria, Southern Italy. The site is characterized by a local wind circulation pattern that results in a clear differentiation between Western-seaside winds, which are normally depleted in pollutants and GHGs, and Northeastern-continental winds, which are enriched in these compounds. This study is the first detailed attempt at evaluating ozone concentrations at LMT and their correlations with meteorological parameters, providing new insights into the source of locally observed tropospheric ozone mole fractions. This research shows that surface ozone daily and seasonal patterns at LMT are “reversed” compared to the patterns observed by comparable studies applied to other parameters and compounds, thus confirming the general complexity of anthropogenic emissions into the atmosphere and their numerous effects on atmospheric chemistry. These observations could contribute to the monitoring and verification of new regulations and policies on environmental protection, cultural heritage preservation, and the mitigation of human health hazards in Calabria. Full article

This study conducted a Life Cycle Assessment (LCA) of alternative (electric and hydrogen) and conventional diesel buses in a large metropolitan area. The primary focus was on hydrogen derived from coke oven gas, a byproduct of the coking process, which is a crucial step in the steel production value chain. The functional unit was 1,000,000 km traveled over 15 years. LCA analysis using SimaPro v9.3 revealed significant environmental differences between the bus types. Hydrogen buses outperformed electric buses in all 11 environmental impact categories and in 5 of 11 categories compared to conventional diesel buses. The most substantial improvements for hydrogen buses were observed in ozone depletion (8.6% of diesel buses) and global warming (29.9% of diesel buses). As a bridge to a future dominated by green hydrogen, employing grey hydrogen from coke oven gas in buses provides a practical way to decrease environmental harm in regions abundant with this resource. This interim solution can significantly contribute to climate policy goals. Full article

This study is dedicated to the investigation of the relationship between the wave activity in February and temperature variations in the Arctic lower stratosphere in March. To study this relationship, the correlation coefficients (CCs) between the minimum temperature of the Arctic lower stratosphere in March (Tmin) and the amplitude of the planetary wave with zonal number 1 (PW1) in February were calculated. Tmin determines the conditions for the formation of polar stratospheric clouds (PSCs) following the chemical destruction of the ozone layer. The NCEP and ERA5 reanalysis data and the modern and future climate simulations of the Earth system models INM CM5 and SOCOLv4 were employed. It is shown that the maximum significant CC value between Tmin at 70 hPa in the polar region in March and the amplitude of the PW1 in February in the reanalysis data in the lower stratosphere is 0.67 at the pressure level of 200 hPa. The CCs calculated using the model data are characterized by maximum values of ~0.5, also near the same pressure level. Thus, it is demonstrated that the change in the planetary wave activity in the lower extratropical stratosphere in February can be one of the predictors of the Tmin. For further analysis of the dynamic structure in the lower stratosphere, composites of 10 seasons with the lowest and highest Tmin of the Arctic lower stratosphere in March were assembled. For these composites, differences in the vertical distribution and total ozone content, surface temperature, and residual meridional circulation (RMC) were considered, and features of the spatial distribution of wave activity fluxes were investigated. The obtained results may be useful for the development of forecasting of the Arctic winter stratosphere circulation, especially for the late winter season, when substantial ozone depletion occurs in some years. Full article

Fresh-cut fruits and vegetables have become more popular among consumers because of their nutritional value and convenience. However, the lower shelf life of fresh-cut fruits and vegetables due to processing and mechanical damage is a critical factor affecting their market expansion, and advances in preservation technology are needed to prolong their shelf life. Some traditional chemical preservatives are disliked by health-seeking consumers because of worries about toxicity. Chemical preservation is inexpensive and highly efficient, but sometimes it carries risks for human health. Biological preservation methods are safer and more appealing, but they are not applicable to large-scale production. Physical fresh-keeping methods have been used for the storage and transportation of fresh-cut fruits and vegetables due to the ease of application. This review discusses current research in fresh-keeping technology for the preservation of fresh-cut fruits and vegetables. Preservation methods include low temperature, modified atmosphere packaging, cold plasma, pulsed light, ultrasonics, ultraviolet light, and ozonated water. As promising alternatives to chemical methods, these novel processes have been evaluated singly or combined with natural preservatives or other methods to extend the shelf life of fresh-cut fruits and vegetables and to provide references and assessments for further development and application of fresh-cut fruit and vegetable preservation technology. Full article

Background: Diabetes ranks high among worldwide global health problems, and diabetic foot ulcer syndrome (DFU) is considered as one of its most serious complications. The purpose of this study was to evaluate the impact of local ozone therapy procedures on the wound healing process in patients with two DFU types: neuropathic and ischemic. Material and Methods: In the retrospective study reported here, the treatment outcomes of 90 patients were analyzed: 44 males (48.8%) and 46 females (51.2%), in the age range between 38 and 87 years of age, with neuropathic (group 1) and ischemic (group 2) diabetic foot ulcers treated by means of local ozone therapy. The assessment of therapeutic effects in both groups of patients included an analysis of the rate of ulcer healing using planimetry and an analysis of the intensity of pain associated with ulcers performed using the VAS scale. Results: After the application of ozone therapy procedures, a statistically significant decrease in the surface area of the ulcers was obtained in both groups of patients, respectively: in group 1 from 7 (6–7.5) cm² to 3 (2–3.5) cm² and in group 2 from 7.5 (6.5–8) cm² to 5 (4.5–5.5) cm² (p < 0.001), with a complete healing of ulcers not observed in any patients from groups 1 and 2. After treatment, the surface area of the assessed ulcers was smaller in the neuropathic group. The intensity of pain experienced after treatment also decreased with statistical significance in both groups (p < 0.001). Conclusions: Short-term local ozone therapy was effective in promoting wound healing and alleviating pain in patients with DFUs of both neuropathic and ischemic etiology. The effectiveness of therapy in the neuropathic type of DFUs was significantly higher than in the ischemic type, in which patients had a higher incidence of risk factors and more advanced lesions, characterized by a larger initial ulcer area and greater intensity of pain. Full article

Carbonyl compounds are important oxygenated volatile organic compounds (VOCs) that play significant roles in the formation of ozone (O₃) and atmospheric chemistry. This study presents comprehensive field observations of carbonyl compounds during an unusual wintertime ozone pollution event at a suburban site in Guangzhou, South China, from 19 to 28 December 2020. The aim was to investigate the characteristics and sources of carbonyls, as well as their contributions to O₃ formation. Formaldehyde, acetone, and acetaldehyde were the most abundant carbonyls detected, with average concentrations of 7.11 ± 1.80, 5.21 ± 1.13, and 3.00 ± 0.94 ppbv, respectively, on pollution days, significantly higher than those of 2.57 ± 1.12, 2.73 ± 0.88, and 1.10 ± 0.48 ppbv, respectively, on nonpollution days. The Frame for 0-D Atmospheric Modeling (F0AM) box model simulations revealed that local production accounted for 62–88% of observed O₃ concentrations during the pollution days. The calculated ozone formation potentials (OFPs) for various precursors (carbonyls and VOCs) indicated that carbonyl compounds contributed 32.87% of the total OFPs on nonpollution days and 36.71% on pollution days, respectively. Formaldehyde, acetaldehyde, and methylglyoxal were identified as the most reactive carbonyls, and formaldehyde ranked top in OFPs, and it alone contributed 15.92% of total OFPs on nonpollution days and 18.10% of total OFPs on pollution days, respectively. The calculation of relative incremental reactivity (RIR) indicates that ozone sensitivity was a VOC-limited regime, and carbonyls showed greater RIRs than other groups of VOCs. The model simulation showed that secondary formation has a significant impact on formaldehyde production, which is primarily controlled by alkenes and biogenic VOCs. The characteristic ratios and backward trajectory analysis also indicated the indispensable impacts of local primary sources (like industrial emissions and vehicle emissions) and regional sources (like biomass burning) through transportation. This study highlights the important roles of carbonyls, particularly formaldehyde, in forming ozone pollution in megacities like the Pearl River Delta region. Full article

This paper investigates the impact of air quality and climate variability during the first wave of COVID-19 associated with accelerated transmission and lethality in Wuhan in China and four European metropolises (Milan, Madrid, London, and Bucharest). For the period 1 January–15 June 2020, including the COVID-19 pre-lockdown, lockdown, and beyond periods, this study used a synergy of in situ and derived satellite time-series data analyses, investigating the daily average inhalable gaseous pollutants ozone (O₃), nitrogen dioxide (NO₂), and particulate matter in two size fractions (PM2.5 and PM10) together with the Air Quality Index (AQI), total Aerosol Optical Depth (AOD) at 550 nm, and climate variables (air temperature at 2 m height, relative humidity, wind speed, and Planetary Boundary Layer height). Applied statistical methods and cross-correlation tests involving multiple datasets of the main air pollutants (inhalable PM2.5 and PM10 and NO₂), AQI, and aerosol loading AOD revealed a direct positive correlation with the spread and severity of COVID-19. Like in other cities worldwide, during the first-wave COVID-19 lockdown, due to the implemented restrictions on human-related emissions, there was a significant decrease in most air pollutant concentrations (PM2.5, PM10, and NO₂), AQI, and AOD but a high increase in ground-level O₃ in all selected metropolises. Also, this study found negative correlations of daily new COVID-19 cases (DNCs) with surface ozone level, air temperature at 2 m height, Planetary Boundary PBL heights, and wind speed intensity and positive correlations with relative humidity. The findings highlight the differential impacts of pandemic lockdowns on air quality in the investigated metropolises. Full article

Wastewater Treatment Plants (WWTPs) encompass a range of processes from preliminary to advanced stages. Conventional treatments are increasingly inadequate for handling emergent pollutants, particularly organic compounds with carcinogenic potential that pose risks to aquifers. Recent advancements prioritize integrating Advanced Oxidation Processes (AOPs) and adsorbents with conventional methods to effectively retain organic pollutants and enhance mineralization. There is a growing preference for non-chemical or minimally chemical approaches. Innovations such as combining ozone and other biological processes with photo-sono-assisted methods, alongside integrating AOPs with adsorbents, are promising. These approaches leverage catalyst-assisted reactions to optimize oxidation efficiency. This review aims to provide a holistic perspective on WWTP processes, spanning wastewater intake to the production of potable water, highlighting key technologies, operational challenges, and future trends. The focus is on advancing sustainable practices and enhancing treatment efficacy to safeguard water quality and address evolving environmental concerns effectively. Full article

Smart environments exploit rising technologies like Internet of Things (IoT) and edge intelligence (EI) to achieve unseen effectiveness and efficiency in every tasks, including air sanitization. The latter represents a key preventative measure–made even more evident by the COVID-19 pandemic–to significantly reduce disease transmission and create healthier and safer indoor spaces, for the sake of its occupants. Therefore, in this paper, we present an IoT-based system aimed at the continuous monitoring of the air quality and, through EI techniques, at the proactively activation of ozone lamps, while ensuring safety in sanitization. Indeed, these devices ensure extreme effectiveness in killing viruses and bacteria but, due to ozone toxicity, they must be properly controlled with advanced technologies for preventing occupants from dangerous exposition as well as for ensuring system reliability, operational efficiency, and regulatory compliance. Full article

The rapid formation of secondary nitrate (NO₃⁻) contributes significantly to the nocturnal increase of PM_2.5 and has been shown to be a critical factor for aerosol pollution in the North China Plain (NCP) region in summer. To explore the nocturnal NO₃⁻ formation pathways and the influence of ozone (O₃) on NO₃⁻ production, the WRF-CMAQ model was utilized to simulate O₃ and PM_2.5 co-pollution events in the NCP region. The simulation results demonstrated that heterogeneous hydrolysis of dinitrogen pentoxide (N₂O₅) accounts for 60% to 67% of NO₃⁻ production at night (22:00 to 05:00) and is the main source of nocturnal NO₃⁻. O₃ enhances the formation of NO₃ radicals, thereby further promoting nocturnal N₂O₅ production. In the evening (20:00 to 21:00), O₃ sustains the formation of hydroxyl (OH) radicals, resulting in the reaction between OH radicals and nitrogen dioxide (NO₂), which accounts for 48% to 64% of NO₃⁻ formation. Our results suggest that effective control of O₃ pollution in NCP can also reduce NO₃⁻ formation at night. Full article

Water treated with ion ozone improves the technological qualities of food products. Therefore, ion-ozonated water was used in the work, and whole-grain flour from soft wheat of the Almaly variety and pumpkin powder were used as raw materials to improve the quality and nutritional value of the pasta. This study investigated the effects of ion-ozone concentration in ion-ozonated water C_io, water temperature t_w, pumpkin powder content C_pp and drying temperature t_d on various characteristics affecting the quality of pasta, including its organoleptic physical, chemical, and rheological properties. These characteristics were assessed by conducting multiple experiments, a total of 25 indicators were determined, such as humidity, acidity, cooking properties, deformation, and other basic quality indicators. To reduce the number of experiments and obtain a reliable assessment of the influence of individual factors on the quality indicators of pasta, methods involving the multifactorial design of experiments were applied. Data processing and all necessary calculations were carried out using the PLAN sequential regression analysis program. Consequently, our findings indicate that minimizing dry water (DM) loss in cooking water requires a dual approach: increasing ion-ozone concentration and optimizing pasta composition and drying conditions, specifically by reducing pumpkin powder content and drying temperature. As a result, it was established that to obtain high-quality pasta from whole-grain flour with high quality and rheological properties, it is necessary to use the following optimal production modes: ion-ozone concentration in ion-ozonated water C_io = 2.5 × 10⁻⁶ mg/cm³, water temperature t_w = 50 °C, pumpkin powder content C_pp = 3.0%, and pasta drying temperature t_d = 50 °C. The resulting pasta is an environmentally friendly product with a high content of biologically active substances. Full article

Ultraviolet solar radiation at the Earth’s surface significantly impacts both human health and ecosystems. A biologically effective daily radiant exposure (BEDRE) model is proposed for various biological processes with an analytical formula for its action spectrum. The following processes are considered: erythema formation, previtamin D3 synthesis, psoriasis clearance, and inactivation of SARS-CoV-2 virions. The BEDRE model is constructed by multiplying the synthetic BEDRE value under cloudless conditions by a cloud modification factor (CMF) parameterizing the attenuation of radiation via clouds. The CMF is an empirical function of the solar zenith angle (SZA) at midday and the daily clearness index from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) measurements on board the second-generation Meteosat satellites. Total column ozone, from MERRA-2 reanalysis, is used in calculations of clear-sky BEDRE values. The proposed model was trained and validated using data from several European ground-based spectrophotometers and biometers for the periods 2014–2023 and 2004–2013, respectively. The model provides reliable estimates of BEDRE for all biological processes considered. Under snow-free conditions and SZA < 45° at midday, bias and standard deviation of observation-model differences are approximately ±5% and 15%, respectively. The BEDRE model can be used as an initial validation tool for ground-based UV data. Full article

The significant increase in ambient ozone (O₃) levels across China highlights the urgent need to investigate the sources and mechanisms driving regional O₃ events, particularly in densely populated urban areas. This study focuses on Xi’an, located in northwestern China on the Guanzhong Plain near the Qinling Mountains, where the unique topography contributes to pollutant accumulation. Urbanization and industrial activities have significantly increased pollutant emissions. Utilizing the Weather Research and Forecasting–Community Multiscale Air Quality Model (WRF-CMAQ), we analyzed the contributions of specific regional and industrial sources to rising O₃ levels, particularly during an atypical winter event characterized by unusually high concentrations. Our findings indicated that boundary conditions were the primary contributor to elevated O₃ levels during this event. Notably, Xianyang and Baoji accounted for 30% and 22% of the increased O₃ levels in Xi’an, respectively. Additionally, residential sources and transportation accounted for 31% and 28% of the O₃ increase. Within the Xi’an metropolitan area, Baqiao District (18–27%) and Weiyang District (23–30%) emerged as leading contributors. The primary industries contributing to this rise included residential sources (28–37%) and transportation (35–43%). These insights underscore the need for targeted regulatory measures to mitigate O₃ pollution in urban settings. Full article

Surface ozone (O₃) pollution has adverse impacts on the yield of winter wheat. The North China Plain (NCP), one of the globally significant primary regions for winter wheat production, has been frequently plagued by severe O₃ pollution in recent years. In this study, the effects of O₃ pollution on winter wheat yield and economic impact were evaluated in the NCP during the 2015–2018 seasons using the regional atmospheric chemical transport model (WRF-Chem), O₃ metrics including the phytotoxic surface O₃ dose above 12 nmol m⁻² s⁻¹ (POD₁₂), and the accumulated daytime O₃ above 40 ppb (AOT40). Results showed that the modeled O₃, exposure-based AOT40, and flux-based POD₁₂ increased during the winter wheat growing season from 2015 to 2018. The annual average daytime O₃, exposure-based AOT40, and flux-based POD₁₂ were 44 ppb, 5.32 ppm h, and 1.78 mmol m⁻², respectively. During 2015–2018, winter wheat relative production loss averaged 10.9% with AOT40 and 14.6% with POD₁₂. This resulted in an average annual production loss of 12.4 million metric tons, valued at approximately USD 4.5 billion. This study enhances our understanding of the spatial sensitivity of winter wheat to O₃ impacts, and suggests that controlling O₃ pollution during the key growth stages of winter wheat or improving its O₃ tolerance will enhance food security. Full article

The ever-increasing industrialization of certain areas of the planet combined with the simultaneous degradation of the natural environment are alarming phenomena, especially in the field of human health. The concentration of particulate matter with an aerodynamic diameter of 2.5 μm (PM_2.5) and 10 μm (PM₁₀), nitrogen oxides (NO_x), carbon monoxide (CO), sulfur dioxide (SO₂), and ozone (O₃) needs constant monitoring, as they consist of the main cause for many diseases. Based on the existence of statutory limits from the World Health Organization (WHO) for the concentration of each of the aforementioned air pollutants, it is considered necessary to develop forecasting systems that have the ability to correlate the current meteorological data with the concentrations of the above pollutants. In this work, the attempt to predict air pollutant concentrations in the wider area of Beijing, China, is successfully carried out using artificial neural network (ANN) models. In the frame of a specific work, a significant number of ANNs are developed. For this purpose, an open-access meteorological and air pollution database was used. Finally, a statistical evaluation of the developed prognostic models was carried out. The results showed that ANNs present a remarkable prognostic ability in order to forecast air pollution levels in an urban environment. Full article