Synthesis of δ-MnO2 via ozonation routine for low temperature formaldehyde removal.

Nowadays, it is still a challenge to prepared high efficiency and low cost formaldehyde (HCHO) removal catalysts in order to tackle the long-living indoor air pollution. Herein, δ-MnO2 is successfully synthesized by a facile ozonation strategy, where Mn2+ is oxidized by ozone (O3) bubble in an alkaline solution. It presents one of the best catalytic properties with a low 100% conversion temperature of 85°C for 50 ppm of HCHO under a GHSV of 48,000 mL/(g·hr). As a comparison, more than 6 times far longer oxidation time is needed if O3 is replaced by O2. Characterizations show that ozonation process generates a different intermediate of tetragonal ß-HMnO2, which would favor the quick transformation into the final product δ-MnO2, as compared with the relatively more thermodynamically stable monoclinic γ-HMnO2 in the O2 process. Finally, HCHO is found to be decomposed into CO2 via formate, dioxymethylene and carbonate species as identified by room temperature in-situ diffuse reflectance infrared fourier transform spectroscopy. All these results show great potency of this facile ozonation routine for the highly active δ-MnO2 synthesis in order to remove the HCHO contamination.

Investigation of spatiotemporal distribution and formation mechanisms of ozone pollution in eastern Chinese cities applying convolutional neural network.

Severe ground-level ozone (O3) pollution over major Chinese cities has become one of the most challenging problems, which have deleterious effects on human health and the sustainability of society. This study explored the spatiotemporal distribution characteristics of ground-level O3 and its precursors based on conventional pollutant and meteorological monitoring data in Zhejiang Province from 2016 to 2021. Then, a high-performance convolutional neural network (CNN) model was established by expanding the moment and the concentration variations to general factors. Finally, the response mechanism of O3 to the variation with crucial influencing factors is explored by controlling variables and interpolating target variables. The results indicated that the annual average MDA8-90th concentrations in Zhejiang Province are higher in the northern and lower in the southern. When the wind direction (WD) ranges from east to southwest and the wind speed (WS) ranges between 2 and 3 m/sec, higher O3 concentration prone to occur. At different temperatures (T), the O3 concentration showed a trend of first increasing and subsequently decreasing with increasing NO2 concentration, peaks at the NO2 concentration around 0.02 mg/m3. The sensitivity of NO2 to O3 formation is not easily affected by temperature, barometric pressure and dew point temperature. Additionally, there is a minimum [Formula: see text] at each temperature when the NO2 concentration is 0.03 mg/m3, and this minimum [Formula: see text] decreases with increasing temperature. The study explores the response mechanism of O3 with the change of driving variables, which can provide a scientific foundation and methodological support for the targeted management of O3 pollution.

Rising frequency of ozone-favorable synoptic weather patterns contributes to 2015-2022 ozone increase in Guangzhou.

Objective weather classification methods have been extensively applied to identify dominant ozone-favorable synoptic weather patterns (SWPs), however, the consistency of different classification methods is rarely examined. In this study, we apply two widely-used objective methods, the self-organizing map (SOM) and K-means clustering analysis, to derive ozone-favorable SWPs at four Chinese megacities in 2015-2022. We find that the two algorithms are largely consistent in recognizing dominant ozone-favorable SWPs for four Chinese megacities. In the case of classifying six SWPs, the derived circulation fields are highly similar with a spatial correlation of 0.99 between the two methods, and the difference in the mean frequency of each SWP is less than 7%. The six dominant ozone-favorable SWPs in Guangzhou are all characterized by anomaly higher radiation and temperature, lower cloud cover, relative humidity, and wind speed, and stronger subsidence compared to climatology mean. We find that during 2015-2022, the occurrence of ozone-favorable SWPs days increases significantly at a rate of 3.2 day/year, faster than the increases in the ozone exceedance days (3.0 day/year). The interannual variability between the occurrence of ozone-favorable SWPs and ozone exceedance days are generally consistent with a temporal correlation coefficient of 0.6. In particular, the significant increase in ozone-favorable SWPs in 2022, especially the Subtropical High type which typically occurs in September, is consistent with a long-lasting ozone pollution episode in Guangzhou during September 2022. Our results thus reveal that enhanced frequency of ozone-favorable SWPs plays an important role in the observed 2015-2022 ozone increase in Guangzhou.

Ozone production sensitivity analysis for the Chengdu Plain Urban Agglomeration based on a multi-site and two-episode observation.

Chengdu Plain Urban Agglomeration (CPUA) is one of the most serious areas suffering from ozone pollution in China. A comprehensive field observation focused on the ozone production rate and its sensitivity was conducted at CPUA in the summer of 2019. Six sampling sites were set and two ozone pollution episodes were recognized. The daily maximum 8-h average (MDA8) O3 concentration reached 137.9 ppbv in the urban sites during the ozone pollution episode. Peak concentration of O3 was closely related to intense solar radiation, high temperatures, and precursor emissions. The OH-HO2-RO2 radical chemistry and ozone production rate (P(O3)) were calculated using an observation-based model (OBM). The daily peak OH concentration varied in the range of 3-13 × 106 molecules cm-3, and peak HO2 and RO2 were in the range of 2-14 × 108 molecules cm-3 during ozone pollution episodes. During the ozone pollution episode, the average maximum of P(O3) in suburban sites (about 30 ppbv h-1.) was compared with urban sites, and the maximum of P(O3) was 18 ppbv h-1 in rural sites. The relative incremental reactivity (RIR) results demonstrate that it was a VOCs-limited regime in the central urban area of Chengdu, with NOx suppression effect in some regions. In the southern neighboring suburb of Chengdu, it was VOCs-limited as well. However, the northern suburban area was a transition region. In the remote rural areas of the southern CPUA, it was highly NOx-limited. Local ozone production driven by the photochemical process is crucial to the ozone pollution formation in CPUA. The geographically differentiated recognition of the ozone regime found by this study can help to tailor control strategies for local conditions and avoid the negative effects of a one-size-fits-all approach.

Ozone modification of waxy rice starch nanocrystals: Effects on the multi-scale structural and surface properties.

The rich active hydroxyl groups on starch nanocrystals (SNC) surface limits its dispersion and stability in the aqueous phase. To address this issue, ozone modification for 0 (SNC), 0.5 (SNC-1), 1 (SNC-2), 1.5 (SNC-3), and 2 h (SNC-4) as compared to conventionally chemical methods was applied to functionally modify the SNC. The impact of ozone treatment on the structural and surface characteristics of waxy rice starch nanocrystals. The findings revealed that longer ozone treatment durations favored the formation of carbonyl groups in starch molecules. Initially, ozone oxidized the hydroxyl group of the macromolecule. Once the carbonyl groups formed, the cross-linking reaction occurred among starch nanocrystals through condensation reactions, leading to the increasing molecular orderliness. X-ray photoelectron spectroscopy, X-ray diffraction and Small-angle X-ray scattering analyses of SNC-2 supported this finding with a reduced O/C ratio, and implied that surface oxidation did not alter the crystal type but rather enhanced molecular hydration in an aqueous system, leading to increased interfacial thickness and fractal dimension. Additionally, ozone oxidation improved surface properties such as charge and hydrophobicity. Oxidized SNC also exhibited altered gelatinization properties due to surface degradation. This study offers a promising strategy for enhancing SNC surface properties, crucial for food science applications.

Effect of ozone oxidation on gastrointestinal digestion and absorption characteristics of silver carp (Hypophthalmichthys molitrix) surimi gels in vitro.

To investigate the quality of different ozone-oxidized surimi gels and their in vitro digestion and absorption characteristics, surimi rinsed with different concentrations of ozonated water (0, 8, 26 mg/L) were prepared. Then, the degree of oxidation and gel structure of surimi were determined, the in vitro digestion and absorption of the gels were simulated, and the digestion and absorption products were analyzed by LC-MS/MS. The results showed that the quality of surimi gels was improved after proper ozone oxidation. After ozone water rinsing, the dry matter digestibility, peptide, and amino acid content increased, and the changes of all three were in line with the Logistic kinetic model (R2 = 0.95-0.99). Caco-2 cell absorption experiments showed that the absorption rate of peptides and amino acids decreased after ozone water rinsing. In summary, ozone oxidation can promote the digestion of surimi gels, but it also reduces the absorption of peptides and amino acids by Caco-2 cells. This study provides a reference for the application of ozone in the food field.

Ozone-Assisted Cu-Based Catalysts for the Efficient Electro-Reforming Glycerol to Formic Acid.

Glycerol electrooxidation reaction (GOR) to produce value-added chemicals, such as formic acid, could make more efficient use of abundant glycerol and meet future demand for formic acid as a fuel for direct or indirect formic acid fuel cells. Non-noble metal Cu-based catalysts have great potential in electro-reforming glycerol to formic acid. However, the high activity, selectivity and stability of Cu based catalysts in GOR cannot be achieved simultaneously. Here, we used ozone-assisted electrocatalyst to convert glycerol to formic acid under alkaline conditions, the onset potential was reduced by 60 mV, the Faraday efficiency (FE) reached 95%. The catalyst has excellent stability within 300 h at the current density of 10 mA cm-2. The electron spin resonance proved that ozone produced superoxide anion during the GOR. In situ Raman spectroscopy, electrochemical studies showed that glycerol can be activated with ozone in GOR, and the C-C bond can be broken to reduce the polymerization of glycerol on the catalyst surface, so as to produce more formic acid at a lower voltage. Moreover, the removal of dissolved O3 from water can be up to 100% after 30 minutes of GOR reaction at a solubility of 50 mg L-1 as measured by UV-VIS spectrophotometry.

Canine oocyte nuclear maturation with Nano-ozone (NZS) supplementation: The alterations of antioxidant, and oxidant status and CDK1, cyclin B1 expressions.

This study aims to evaluate the effects of nano-ozone solution (NZS) on canine oocyte nuclear maturation, associated with the alterations of antioxidant and oxidant status and cyclin-dependent kinase 1 (CDK1), cyclin B1 gene expressions. Oocytes were cultured in four distinct concentrations of NZS (0.5, 1, 2, and 5 µg/mL) and parthenogenetically activated. The rates of oocytes arrested at the Germinal Vesicle (GV), Germinal Vesicle Breakdown (GVBD), Metaphase I (MI), and Metaphase II (MII) stages were statistically different among groups (P < 0.05). The oocytes cultured in 1 µg/mL NZS yielded the best oocyte maturation rate at the MI and MII stages; however, the lowest maturation and high degeneration rates were observed in Group E. The measurements of Malondialdehyde (MDA), reduced Glutathione (GSH), Superoxide Dismutase (SOD), and Ferric Reducing/Antioxidant Power assay (FRAP) were performed from IVM culture media. No statistical difference was observed in SOD and MDA results (P > 0.05). GSH levels were statistically significant between Group A-Group E (p = 0.003), Group B-Group E (p = 0.045), and Group E-Group D (p = 0.021). The culture media in Group D and Group E had high FRAP concentrations and significantly differed between groups (P < 0.05). CDK1, and cyclin B1 genes, which are subunits of maturation-promoting factor (MPF), are upregulated in Group B and Group C, while are downregulated in oocytes of Group E. This study showed that low, controlled doses of NZS (1 µg/mL) supplementation could improve the meiotic competence of canine oocytes and lead to positive response in expressions of CDK1 and cyclin B1 on the gene level.

Use of machine learning algorithms to determine the relationship between air pollution and cognitive impairment in Taiwan.

Air pollution has become a major global threat to human health. Urbanization and industrialization over the past few decades have increased the air pollution. Plausible connections have been made between air pollutants and dementia. This study used machine learning algorithms (k-nearest neighbors, random forest, gradient-boosted decision trees, eXtreme gradient boosting, and CatBoost) to investigate the association between cognitive impairment and air pollution. Data from the Taiwan Biobank and 75 air-pollution-monitoring stations in Taiwan were analyzed to determine individual levels of exposure to air pollutants. The pollutants examined were particulate matter with a diameter of ≤ 2.5 µm (PM2.5), nitrogen dioxide, nitric oxide, carbon monoxide, and ozone. The results revealed that the most strongly correlated with cognitive impairment were ozone, PM2.5, and carbon monoxide levels with adjustment of educational level, age, and household income. The model based on these factors achieved accuracy as high as 0.97 for detecting cognitive impairment, indicating a positive association between air pollutions and cognitive impairment.

Efficacy of ozone therapy for oral mucosa wound healing: a systematic review and meta-analysis.

OBJECTIVES: To conduct a systematic review and meta-analysis to assess the effectiveness of ozone therapy in oral ulcers healing when compared to placebo or active treatments. MATERIALS AND METHODS: The search was carried out using PubMed, EMBASE, Scopus, and Lilacs databases. Clinical trials involving human participants were included. The Risk Ratio (RR) and the standardized mean difference (SMD) with 95%CI (confidence interval) were calculated. The ROBINS-I (risk of bias in non-randomized studies of interventions) and RoB2 (risk of bias tool for randomized trials) assessment tool was used to detect bias. RESULTS: After the selection process, 12 studies were included. The meta-analysis showed that ozone therapy helps to reduce the size of the traumatic and autoimmune ulcers (RR=-0.44; 95% CI -0.71,-0.17; I2=0%) in comparison to placebo. Regarding pain reduction, ozone was superior to placebo (RR = 1.29, 95% CI -1.6 to -0.95); I2=0%), and equivalent to topical corticosteroid and laser photobiomodulation (RR = 0.26, 95% CI -0.27,0.78, p = 0.34). CONCLUSION: Ozone therapy is an alternative for accelerating healing and reducing pain for both traumatic and autoimmune ulcers. However, the quality of evidence is limited. CLINICAL RELEVANCE: Oral ulcerations are usually painful and impact quality of life requiring different approaches to boost wound healing and reduce symptoms. For this purpose, ozone therapy is a promising strategy.

Changing ozone sensitivity in Fujian province, China, during 2012-2021: Importance of controlling VOC emissions.

In the troposphere, ozone (O3) formation can be limited by NOx, VOCs, or both, complicating efforts to reduce O3 by controlling its precursors. This study used formaldehyde (HCHO) data and nitrogen dioxide (NO2) data from the Ozone Monitoring Instrument (OMI) to analyze O3 formation sensitivity in Fujian from 2012 to 2021. Over the past decade, an 8.7% reduction in NO2 VCDs and a 9.91% increase in HCHO VCDs were observed. Due to differences in the primary driving factors, HCHO VCDs exhibit a characteristic seasonal pattern with higher in summer and lower in winter, whereas NO2 VCDs show the opposite trend. O3 formation chemistry was accurately diagnosed by combining satellite-based data and ground-based O3 data. A new threshold value (3.3 to 4.6) was derived to determine the transition from VOC-limited to NOx-limited O3 formation regimes. Results showed that O3 sensitivity exhibited pronounced seasonal variations. The VOC-limited regime predominates throughout the entire Fujian region in winter, whereas it occupies only 5% of the area in summer. A VOC-limited region was found widely across Fujian on an annual average, but it decreased by 24% over 10 years. Transitional areas experienced a 19% increase. In two natural emission reduction cases (reductions during the Chinese Lunar New Year holiday and reductions in weekend traffic emissions compared to weekdays), ground-level O3 effectively captured the impacts of sensitivity changes. The impact suggests that when Fujian is in the VOC control region, a significant reduction in NOx, without effective VOC control, might lead to an O3 increase. The importance of controlling VOC emissions is highlighted in Fujian. This study enhances the understanding of O3 formation regimes in southeastern China, which is crucial for developing O3 prevention and control strategies.

A cautious note advocating the use of ensembles of models and driving data in modeling of regional ozone burdens.

We investigate the performance of two widely used chemistry-transport models (CTMs) with different chemical mechanisms in reproducing the ambient maximum daily 8-h average ozone (MDA8 O3) burden over Central Europe. We explore a base case setup with boundary conditions (BC) for meteorology from the ERA-Interim reanalysis and chemical BC from CAM-Chem as well as effects of alterations in these BC based on global model fields. Our results show that changes in meteorological BC strongly affect the correlation with observations but only marginally affect the model biases, while changes in chemical BC increase model biases while correlation patterns remain largely unchanged. Furthermore, our study highlights that CTM choice (and choice of chemical mechanism) has a similar or even larger impact on MDA8 O3 levels as the impact of altered BC. In summary, our study calls for a multi-model strategy combining different CTM and BC combinations to explore the bandwidth of MDA8 O3 distributions and thus uncertainty in hindcasts and future projections, in analogy to climate studies considering ensemble simulations under the same anthropogenic emissions but with slightly different initial conditions. Supplementary Information: The online version contains supplementary material available at 10.1007/s11869-024-01516-3.

Systemic Ozone Therapy May Improve the Perception of Quality of Life: Ozonized Glucose Solution 5% Extends Reach to Patients Ineligible for Blood Infusion.

Ozone therapy is a complementary treatment that has gained popularity due to its safety and wide range of applications. Systemic ozone therapy involves withdrawing 100 to 200 ml of blood, treating it with an oxygen-ozone mixture, and then reinfusing it. This process requires large-caliber venous access, which can be a limitation. To overcome this, alternative administration methods have been explored, including the use of ozonized solutions. The aim of this study is to evaluate the clinical effects of systemic ozone therapy on the perception of quality of life and to analyze the outcomes of different administration methods. Three groups of patients were treated: one group received classical systemic ozone therapy, another received ozone therapy via intravenous infusion of a 5% glucose solution, and the third group alternated between the two methods. The results showed an improvement in perceived quality of life in all groups, regardless of the method used. Thus, systemic ozone therapy showed efficacy in improving the perception of quality of life in our group. Moreover, intravenous infusion of a 5% glucose solution has made it possible to treat patients who could not be treated with the classical method, achieving similar results.

Tropospheric ozone - hidden cost for the financial performance of French wineries.

The paper investigates how tropospheric ozone affects the financial performance of French wine companies by influencing their operating income, using the Structural Equation Modeling (SEM) methodology. The study encompasses 487 active French wine industry companies from 2010 to 2022, considering various market, climate, and financial factors. The main findings show that high concentrations of tropospheric ozone negatively affect both the quality and quantity of grapes, thereby reducing the operating income of French wine companies and, consequently, their financial performance. More precisely, within the current market conditions and climate context, a 1% rise in tropospheric ozone levels leads to a 10.4% decrease in the operating income of French wine companies, which translates to a 0.7-0.8% decline in their financial performance. A strong market position enables French wine companies to achieve higher revenues, increased profit margins, and sustainable growth. Additionally, lower soil wetness, humidity, and temperature under higher atmospheric pressure improve grapevine growth and grape quality, further boosting revenue. Policy implications for wine producers include adopting site selection, irrigation, and canopy management strategies to enhance grape quality and financial health. Public authorities can address tropospheric ozone pollution through air quality standards, monitoring systems, financial incentives, and educational programs to mitigate its adverse effects.

[The role of ozone in the pathogenesis of allergic rhinitis].

Allergic rhinitis （AR） is a nasal hypersensitivity disease that is influenced by environmental factors, genetic factors, and various inflammatory factors. The role and mechanisms of ozone, as a component of air pollution, in the pathogenesis of AR are not yet fully understood. This article provides a review of the impact of ozone on the epidemiology and pathology of AR, as well as its possible mechanisms, to provide new insights into the prevention and treatment of AR.

Disinfection of Medical Solid Waste through the Application Ozone Technology: Feasibility and Effectiveness Study.

Background: We aimed to determine the feasibility of ozone for disinfection of infectious solid waste in hospital. Methods: Spores of Bacillus atrophaeus were used to monitor the process of inactivating microbial agents using ozone in medical solid waste in the hospitals of Tabriz City, Iran. For this purpose, culture medium containing the mentioned bacteria was placed in the bags containing medical wastes. The ozone generator was equipped with a constant dose of 5 grams per liter, with a discharge of 1 and 3 liters per minute and contact time of 10 to 120 min. Then the ozone exposure indicators were incubated for 24-48h at 36 ± 1 °C and, finally, the absence of colony growth in the culture medium was considered as the success of ozone in disinfection of infectious solid waste. This process was performed with 4-time replications. Results: The complete removal of B. atrophaeus was obtained for non-compacted and compacted infectious solid waste, at contact time of 15 and 50 min, respectively. The efficiency of removal of B. atrophaeus by the process of wet ozone injection through a glass column was 100% in 30 minutes and by separate injection of water vapor into the contact tank was 100% in 50 minutes. The results of this study showed that the use of ozone technology was effective in the inactivation and destruction of microbial agents in medical solid waste. Conclusion: Employing different advanced technology of oxidization especially ozone in order to decrease the environmental pollution is considered as one of management approaches.

Ozone Mortality Burden Changes Driven by Population Aging and Regional Inequity in China in 2013-2050.

Air pollution exposure is closely linked to population age and socioeconomic status. Population aging and imbalance in regional economy are thus anticipated to have important implications on ozone (O3)-related health impacts. Here we provide a driver analysis for O3 mortality burden due to respiratory disease in China over 2013-2050 driven by population aging and regional inequity. Unexpectedly, we find that population aging is estimated to result in dramatic rises in annual O3 mortality burden in China; by 56, 101-137, and 298-485 thousand over the periods 2013-2020, 2020-2030, and 2030-2050, respectively. This reflects the exponential rise in baseline mortality rates with increasing age. The aging-induced mortality burden rise in 2030-2050 is surprisingly large, as it is comparable to the net national mortality burden due to O3 exposure in 2030 (359-399 thousand yr-1). The health impacts of O3 pollution, shown as mortality burden per capita, are inequitably distributed, with more severe effects in less developed provinces than their developed counterparts by 23.1% and 21.5% in 2019 and 2030, respectively. However, the regional inequity in O3 mortality burden is expected to be mitigated in 2050. This temporal variation reflects evolving demographic dividend characterized by a larger proportion of younger individuals in developed regions. These findings are critical for targeted improvement of healthcare services to ensure the sustainability of social development.

Impact of low-dose ozone supplementation on motility parameters and bacterial growth in horse cryopreserved semen.

Two studies were conducted to evaluate the use of medical ozone (O3) in commercial extenders for equine semen cryopreservation. In the first study (Study 1), 0, 5, and 15 µg/mL of O3 were added to diluents of refrigerated or frozen semen. Samples were evaluated for sperm kinematics at different time points for the chilled samples and after a thermoresistence test for the frozen/thawed samples. In the second study (Study 2), 0, 5, and 10 µg/mL of O3 were added to an antibiotic-free diluent for refrigerated semen for comparison with the control group in which semen was diluted in the same diluent enriched with antibiotics. Semen sample kinematics were analyzed and an aliquot was collected after ozonification for bacteriological analyses. For Study 1 no difference was found comparing all the kinematic parameters analyzed over time, in the various treatments (P > 0.05). In Study 2 the absence of antibiotics did not affect the kinematic parameters compared to the control (P > 0.05). However when antibiotics were added, a smaller number of bacterial colony-forming units were detected compared to samples without antibiotics and without or with different O3 supplementations. In conclusion, O3 treatment at low dosages did not affect the semen kinematics, although it was ineffective in preventing bacterial overgrowth. Higher O3 concentrations should be evaluated to explore the possibility of reducing the use of antibiotics in equine sperm conservation.

Prenatal ozone exposure and variations of the gut microbiome: Evidence from a Chinese mother-infant cohort.

BACKGROUND: The gut microbiome is central to human health, but the potential impact of ozone (O3) exposure on its establishment in early life has not been thoroughly examined. Therefore, this study aimed to investigate the relationship between prenatal O3 exposure and the variations of the human gut microbiome during the first two years of life. DESIGN: A cohort study design was used. Pregnant women in the third trimester were recruited from an obstetric clinic, and long-term follow-ups were conducted after delivery. The gut microbiome was analyzed using the 16 S rRNA V3-V4 gene regions. Functional pathway analyses of gut microbial communities in neonates were performed using Tax4fun. The average concentrations of ambient O3 and other air pollutants from pregnancy to delivery were calculated using the China High Air Pollutants (CHAP) dataset, based on the permanent residential addresses of participants. Multiple linear regression and mixed linear models were utilized to investigate the associations between prenatal O3 exposure and gut microbiome features. RESULTS: Prenatal O3 exposure did not significantly affect the gut microbial alpha diversity of mothers and neonates. However, it was found to be positively associated with the gut microbial alpha diversity in 24-month-old infants. Prenatal O3 exposure explained 13.1 % of the variation in neonatal gut microbial composition. After controlling for potential covariates, prenatal O3 exposure was associated with neonatal-specific gut microbial taxa and functional pathways. Furthermore, the mixed linear models showed that prenatal O3 exposure was negatively associated with variations of Streptococcus (p-value = 0.001, q-value = 0.005), Enterococcus (p-value = 0.001, q-value = 0.005), Escherichia-Shigella (p-value = 0.010, q-value = 0.025), and Bifidobacterium (p-value = 0.003, q-value = 0.010). CONCLUSIONS: This study is the first to examine the effects of prenatal O3 exposure on gut microbial homeostasis and variations. It demonstrates that prenatal O3 exposure is associated with variations in certain aspects of the gut microbiome. These findings provide novel insights into the dynamics and establishment of the human microbiome during the first two years of life.

Urban Air Pollution and Plant Tolerance: Omics Responses to Ozone, Nitrogen Oxides, and Particulate Matter.

Urban air pollution is a crucial global challenge, mainly originating from urbanization and industrial activities, which are continuously increasing. Vegetation serves as a natural air filter for air pollution, but adverse effects on plant health, photosynthesis, and metabolism can occur. Recent omics technologies have revolutionized the study of molecular plant responses to air pollution, overcoming previous limitations. This review synthesizes the latest advancements in molecular plant responses to major air pollutants, emphasizing ozone (O3), nitrogen oxides (NOX), and particulate matter (PM) research. These pollutants induce stress responses common to other abiotic and biotic stresses, including the activation of reactive oxygen species (ROSs)-scavenging enzymes and hormone signaling pathways. New evidence has shown the central role of antioxidant phenolic compound biosynthesis, via the phenylpropanoid pathway, in air pollution stress responses. Transcription factors like WRKY, AP2/ERF, and MYB, which connect hormone signaling to antioxidant biosynthesis, were also affected. To date, research has predominantly focused on laboratory studies analyzing individual pollutants. This review highlights the need for comprehensive field studies and the identification of molecular tolerance traits, which are crucial for the identification of tolerant plant species, aimed at the development of sustainable nature-based solutions (NBSs) to mitigate urban air pollution.