Air Levels Research Articles

Development of Livestock-Associated Methicillin-Resistant Staphylococcus aureus (LA-MRSA) Loads in Pigs and Pig Stables During the Fattening Period

Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is widespread in European pig production and poses an occupational hazard to farm workers and their household members. Farm workers are exposed to LA-MRSA through direct contact with pigs and airborne transmission, enabling bacteria to be carried home in the nose or on the skin. Consequently, it is important to consider LA-MRSA in a one-health context, studying human exposure by examining LA-MRSA levels in pigs, air, and dust in the farm environment. In this investigation, LA-MRSA levels were quantified in nasal swab samples from the pigs, air samples, and dust at three different time points in a farm rearing pigs from approx. 30 kg until slaughter. Sampling was repeated across seven batches of pigs, resulting in the analysis of 504 nasal swab samples, alongside air and dust samples. LA-MRSA was cultured and quantified on MRSA2 agar plates. Findings revealed significant batch-to-batch variation and a significant 94.1% decrease in LA-MRSA levels during the rearing period. Despite this decline, all nasal swab samples tested positive, with the highest level reaching 353,000 cfu in a sample. Among the 42 air samples, LA-MRSA levels were low to moderate, with a maximum of 568 and an average of 63 cfu/m3. In the 28 dust samples collected during the second and third sampling periods, LA-MRSA counts were high, reaching up to 37,272 cfu/g, with an average of 17,185 cfu/g. The results suggest that while LA-MRSA levels in pigs decrease with age, reaching low levels before slaughter, the bacterium remains highly abundant in dust, posing an occupational hazard to farm workers.

Assessment of the toxicity and hazard of a chelating agent based on a mixture of di- and triammonium salts of nitrilotriacetic acid in water and atmospheric air

Introduction. The article evaluates the toxicity and danger of a chelating agent based on a mixture of di- and triammonium salts of nitrilotriacetic acid. The relevance of the study is related to the assessment of the impact of this substance on water and atmospheric air, especially in the context of its use in oil production and potential release into the environment and impact on humans. Material and methods. The studies included assessing the effect of the substance on the organoleptic characteristics of water, the process of self-purification of water bodies, as well as conducting acute and subacute toxicological tests to study the effect of the mixture on the body of warm-blooded animals. Results. For a mixture of di- and triammonium salts of nitrilotriacetic acid, a value of 70 mg/l is recommended as the threshold concentration for the organoleptic indicator, the limiting indicator is odor. The mixture does not affect the processes of self-purification of water in water bodies at the maximum studied concentration. Toxicological studies have shown that the mixture is classified in the 3rd hazard class (LD50 2250±250 mg/kg) and has a high degree of accumulation. In addition, it has a moderate irritant effect on the mucous membrane of the eye and intact skin upon repeated application, and does not have a skin-resorptive effect. After prolonged exposure, the mixture affects the blood parameters of animals, as well as the functional state of the liver and kidneys. Limitations. The studies were carried out in accordance with the requirements of Methodological instructions 2.1.5.720–98 and Methodological instructions 2630–82. The research results are applicable in substantiating hygienic standards in the water of water bodies and atmospheric air. Conclusion. Thus, based on literature data, as well as our own research, for a mixture of di- and triamonium salts of nitrilotriacetic acid, we can recommend a value of 0.8 mg/l as the approximate permissible level in the water of water bodies (hazard indicator – sanitary-toxicological, hazard class – 2), and a value of 0.1 mg/m3 as the tentative safe exposure level in the atmospheric air of populated areas.

Sources and determinants of exposure to indoor air pollutants in schools and hospitals: a review

Abstract Background Indoor Air Quality (IAQ) is an important determinant of health. This study aimed to review the available scientific evidence about indoor pollutants and determinants of exposure in several settings, in the scope of the K-HEALTHinAIR project. Methods The systematic review was performed for the sources, concentrations, and determinants of pollutants in schools in the European region for 2013-2023. Articles were selected for data extraction if they were epidemiological studies, reported primary data for indoor air and pollutant levels, and, identified sources and determinants of exposure. Results The main pollutants affecting IAQ in schools and hospitals were carbon dioxide, volatile organic compounds (e.g., formaldehyde, terpenes), particulate matter, nitrogen dioxide, radon, ozone, and carbon monoxide. Besides the outdoor environment, several important indoor sources of emissions were identified such as occupancy, resuspension, cleaning products. Ventilation was the main determinant influencing the indoor levels of pollutants, stressing the importance of good planning, installation, and maintenance of mechanical ventilation systems in buildings. Other determinants were the number of occupants and their activities, and the building characteristics (e.g., type of floor, location, etc). Conclusions Results revealed indoor air quality as a public health concern since several pollutants are present in indoor settings. The identification of sources and determinants of exposure is fundamental for determining preventive measures in a public health perspective. Acknowledgments: K-HEALTHinAIR team for screening and data extraction: Mariana Corda, Jose Fermoso, Alicia Aguado, Sandra Rodriguez, Hanns Moshammer, Mireia Ferri, Belén Costa, Leticia Pérez, Wojciech Hanke, Artur Badyda, Piotr Kepa, Katarzyna Affek, Nina Doskocz, Laura Martín, Oguz Mulayim, Cesar Mediavilla Martinez, Alba Gómez, Ruben González, Isaac Cano, Josep Roca, Simon de Leede.

The Formaldehyde, TVOCs, PM2.5 and PM10 Concentrations at Outdoor Street Food in Kalasin, Thailand

Human health and well-being are directly impacted by air quality. Cardiovascular and respiratory problems have been linked to exposure to pollutants such as formaldehyde, total volatile organic compounds (TVOCs), and particulate matter 2.5 and 10 micrometers (PM2.5 and PM10). This study aimed to quantify formaldehyde, TVOCs, PM2.5, and PM10 levels in the outdoor air at street food vendors in Kalasin, Thailand. The study was conducted at street food vendors in the province of Kalasin. Formaldehyde values at the top five food stalls in Kalasin ranged from 0.58 to 1.41 mg/m3. The PM2.5 values ranged from 2.29 to 9.43 ug/m3, and the TVOC values ranged from 2.91 to 7.02 ug/m3, with PM10 concentrations ranging from 2.86 to 7.29 ug/m3. Drawing on data about these pollutant concentrations across five distinct locations, the following recommendations can be put forth: Elevated levels of formaldehyde, TVOCs, PM2.5, and PM10 in certain areas can have detrimental effects on the environment and human well-being.

Can indoor plants reduce formaldehyde levels in the anatomy dissection hall? A study to evaluate the practicality of using plants in reducing formaldehyde levels

Background Formaldehyde a commonly used embalming fluid for the preservation of cadavers, produces numerous short and long-term side effects on the students and staff working with it. Indoor plants have been shown to reduce atmospheric formaldehyde levels. The purpose of the study was to compare the efficacy of indoor plants in reducing formaldehyde levels in ambient air to levels deemed safe by WHO standards Methods The study was conducted in the storage room of the Anatomical dissection hall. 7 potted plants of one variety were kept in the storage room for 14 days and the Formaldehyde reading was measured using a VOC (Volatile Organic Compound) monitor. Then the same was done with no plant. This cycle was repeated 2 more times, with two different plant species. The three spieces of plants used for this study were as follows: Dracaena trifasciata, Epipremnum aureum, Spathiphyllum. Results The results were analysed and compared and it was determined that the effect of having a plant present versus having no plant present on the Formaldehyde concentration in the air was inconclusive as Dracaena trifasciata failed to reject the null hypothesis altogether (p-value>0.05), while Epipremnum aureum and Spathiphyllum rejected the null hypothesis (p-value<0.05), however they both had a weak positive correlation with formaldehyde concentration. Conclusion The efficacy of indoor plants in reducing formaldehyde levels in ambient air needs to be further explored and validated since all the prior studies conducted were in controlled environment and should be done in a real time scenario for its practical and beneficial uses.

Microplastic levels in the indoor air of buildings based on plastic waste recycling in Indonesia

Introduction: Microplastics are a new type of contamination in the environment caused by plastic fragmentation and degradation. The generation of plastic waste increases every year, therefore efforts are made to recycle it into building materials. It is unclear how building use resulting from recycling plastic waste affects the development of microplastics in the atmosphere. The purpose of this study is to determine the airborne concentrations of microplastics in buildings constructed from recycled plastic waste. Materials and methods: The study measured microplastic levels in the air for 30 days in a miniature building made from plastic waste. Samples taken during the dry season in Indonesia in 2023. Air sampling is carried out by passive method. Visual observation of the shape, and amount of microplastics using a microscope. Results: Microplastics are found in the air of building spaces made from recycled plastic waste with varying levels every day. The average level of microplasty in the air for 30 days was 30,8 particles/m2/day. Maximum microplastic rate of 63 particles/m2/day, and minimum rate of 18 particles/m2/ day. The average air temperature when sampling is 25,48 ºC, air humidity is 68,37 % and ultraviolet intensity is 860 mwatt/cm2. Conclusions: Microplastic levels in the air of building spaces made from recycled plastic waste that can not be identified can be identified whether they are still within safe limits or not. This is because there is no regulation in Indonesia even in the world that regulates the safe limit of microplastic levels in the environment.

Benchmark experimental study on cavitating flow around Clark-Y 11.7 % hydrofoil at various angles of attack under controlled levels of dissolved air

The present research aims to study cavitating flow around a CLARK-Y 11.7 % hydrofoil with variable angles of attack (α) while maintaining controlled levels of dissolved air in the operating fluid, which is water. A series of experiments were conducted using a water tunnel facility, where the cavitation characteristics were measured and observed using sensors and high-speed imaging techniques. The variables studied in the present work are cavitation number (1 ≤ σ ≤ 2.2) and angle of attack (α = 4°, 6°, 8°, 10°, and 12°), with dissolved air levels (DAL) in the range of 9.3 ppm to 13.1 ppm. The dimensionless cavity length decreases significantly with increasing values of σ/α, indicating an inverse relationship where higher cavitation numbers or lower angles of attack result in shorter cavities. The cavity length follows a power-law scaling relationship, with the empirical equation Lmax/C=4.78×σ/α−0.76.Increasing the angle of attack transitions the cavitation nature from stable (Mode I) to dynamic (Mode II) and highly oscillating (Mode III). Larger cavities result in lower Strouhal numbers, which indicates reduced vortex shedding activity. The relationship between the Strouhal number and the normalized cavitation number σ/α is characterized by the power-law equation St=0.041×σ/α0.3. The pressure coefficient at the leading-edge increases with the angle of attack at low cavitation numbers, while higher cavitation numbers lead to greater pressure coefficient differences between the leading and trailing edges.The present study offers an extensive dataset and empirical correlations that may serve as a benchmark framework, which facilitates the validation of computational and experimental models of cavitating flow under similar conditions.

Aachen smoking cessation and harm reduction (ASCHR) trial study protocol – scientific evaluation of a psychological-telemedical counseling concept for smoking cessation in patients with vascular diseases

BackgroundSmoking is a major risk factor of cardiovascular diseases, notably peripheral arterial disease (PAD). Despite this link, research on smoking cessation interventions in PAD patients remains scarce and inconclusive regarding the efficacy of such interventions.Therefore, elucidating it is crucial and should address both individuals who smoke that are motivated to quit and individuals who smoke heavily lacking the motivation to quit.Methods/DesignThe Aachen Smoking Cessation and Harm Reduction (ASCHR) trial is a prospective randomized controlled study (RCT) on the benefits of telemedical-psychological support for smoking cessation in patients with PAD, funded by the “Innovation Fund” of the Joint Federal Committee in Germany. This trial aims to scientifically assess the efficacy, feasibility, acceptance, and efficiency of a multi-stage smoking cessation program based on the recommendations of the German guideline for smoking cessation tailored to patients with PAD, compared to a control group receiving no intervention. Central to the program is psychological counseling utilizing motivational interviewing techniques, delivered through telemedicine via video consultations. The primary endpoint of the ASCHR trial is the smoking cessation rate after 8 months of intervention, with a secondary endpoint evaluating sustained abstinence at a further 6 months follow-up. Smoking cessation is defined as a carbon monoxide level in exhaled air of less than 6 ppm. We hypothesize that the group receiving the multi-stage cessation program will yield a cessation rate at least 10 percentage points higher than that of usual care. Anticipating a dropout rate of around 35%, the planned sample size is at least N = 1032 study participants.DiscussionShould the trial demonstrate significant positive outcomes, efforts should be made to integrate the program into routine care in Germany, potentially offering a promising base for future smoking cessation support among PAD patients.

Analysis of the Effect of More Fuel and Air Variations Excess Air on Combustion Process Simulation at a 10 kW Biomass Power Plant Using ASPEN PLUS

Abstract The utilization of biomass as an alternative energy can support the achievement of Net Zero Emissions. Each type of biomass fuel can provide different combustion effects from one another. This is due to the different heating values of each fuel. The calorific value is one of the things that affect the combustion performance of the biomass power plant. The main purpose of this study is to examine how different amounts of excess air used during the combustion process affect the outcomes. Combustion is a chemical reaction involving decomposition and gasification that simultaneously occurs in a space where a large amount of energy is released. The modeling and simulation of the decomposition and gasification processes were carried out using Aspen Plus. In this simulator, the decomposition process takes place in the Yields Reactor, while the gasification process occurs in the Gibbs Reactor. The biomass and ash components are characterized by their ultimate, proximate, and sulfur analysis. Then the excess air is varied to analyze its impact on the flame temperature from the reaction. The simulation findings emphasize crucial considerations for achieving complete combustion and reducing harmful gas emissions. Maintaining excess air close to the stoichiometric level ensures maximum combustion temperature at 1616.15 °C while minimizing excess air reduces NOx gas concentration. Approaching stoichiometric air level decreases CO gas and increases CO2, indicating more thorough combustion. However, excess air leads to lower adiabatic flame temperature due to nitrogen formation.

Use of Scalp Hair as a Biomarker to Determine Airborne Heavy Metal Concentrations for the Academic Laboratory Employees

Academic chemical laboratories (ACL) are considered public places the employees come in contact with a variety of pollutants. The aim of the current study was to detect heavy metals levels in the indoor air of ACL in two universities in Baghdad city and assess their levels in the academic employees’ scalp hair as biomarkers. Air samples inside ACL were collected to detect Fe, Cd, Zn, Pb and Cu. Scalp hair samples were collected from 40 adult chemical laboratory employees aged 30-60 years, who worked 5 days/week for 6 hours a day. Personal information relating to employees such as age, duration of exposure, smoking habit and sex, was collected as a questionnaire. The results of this study concluded that academic laboratory employees were exposed to high levels of heavy metals which was proven through the use of scalp hair; old ages, prolonged working periods, smoking habit have significant effects in increasing the levels of heavy metals in scalp hair, while the employees’ gender variation did not have a significant effect.

Correlates of Exercise Behavior Based on Socio-Ecological Theoretical Model among Chinese Urban Adults: An Empirical Study.

Identifying the correlates of exercise behavior is essential to combating physical inactivity as a public health concern. The purpose of this study is to identify the correlates of physical activity among urban Chinese adults under the social-ecological theoretical model in order to facilitate targeted interventions to promote physical activity. Using the socio-ecological model, we conducted a questionnaire survey among 1459 urban residents in Zhejiang and Shaanxi provinces of China, collecting data on individual demographic factors, sociological factors, environmental perception, and exercise behavior. Binary logistic regression models were employed to analyze the relationships between exercise behavior and socio-ecological factors. Male gender (p < 0.01), advanced age (p < 0.001), higher education level (p < 0.05), living independently from parents (p < 0.05), absence of childcare responsibilities (p < 0.01), residence in a county/prefecture-level city (p < 0.001), favorable neighborhood esthetics (p < 0.001), available greenways/parks (p < 0.001), and family support for exercise participation (p < 0.05) were significantly correlated with an increased likelihood of participating in physical activity. Male gender (p < 0.001), advanced age (p < 0.001), absence of childcare responsibilities (p < 0.05), good neighborhood vegetation (p < 0.01), availability of free neighborhood exercise facilities (p < 0.05), and support from friends for exercise participation (p < 0.01) were significantly correlated with an increased likelihood of engaging in physical activity for more than 150 min per week. BMI, community air quality, traffic safety, public safety, and level of social development were not major correlates. To promote exercise behavior, more attention should be paid to individuals who are female, young, have lower levels of education, bear childcare responsibilities, or reside in provincial capitals in China. Improving the habitat environment and providing convenient and affordable facilities should also be considered. Furthermore, support from family and friends can positively reinforce exercise behavior.

In vitro assessment of acute airway effects from real-life mixtures of ozone-initiated oxidation products of limonene and printer exhaust

In indoor air the reaction of ozone (O3) with terpenes may lead to the formation of irritating gas-phase products which may induce acute airway effects (i.e. sudden, short-term changes or symptoms related to the respiratory system). We aimed to perform an in vitro study on possible health effects of products from the O3-initiated reaction of limonene with printer exhaust, representing real-life mixtures in offices. Human bronchial epithelial cells were exposed for 1 hour (h) to limonene and O3, combined with printer exhaust. The resulting concentrations represented 34% and 6% of the generated initial concentrations of limonene (400 µg/m³) and O3 (417 µg/cm³), respectively, which were in range of high end realistic indoor concentrations. We observed that the reaction of limonene with O3 generated an increase of ultrafine particles within 1 h, with a significant increase of secondary reaction products 4-oxopentanal and 3-isopropenyl-6-oxo-heptanal at high end indoor air levels. Simultaneous printing activity caused the additional release of micron-sized particles and a further increase in reaction products. Relevant cellular endpoints to evaluate the possible induction of acute airway effects were measured. However, none of the test atmospheres representing office air was observed to induce these effects.

Environmental and Health Impacts Resulting From Burning Solid Waste Near Residential Areas in Diyala Governorate, Iraq

General Background: Rapid development, population growth, and improper disposal of municipal solid waste are prevalent issues in developing countries, leading to significant environmental and health challenges. Specific Background: In Iraq’s Diyala Governorate, the absence of integrated waste management exacerbates pollution through waste burning and heavy metal contamination, posing risks to nearby residential areas. Knowledge Gap: While previous studies have addressed waste management in developing countries, there is limited research on how local waste disposal practices impact air, soil, and water quality in specific areas of Diyala. Aims: This study evaluates the air quality and levels of heavy metals in soil and water near five landfill sites in Diyala Governorate: Kanaan, Al-Khalis, Baladruz, Khanaqin, and Hamrin, aiming to assess the pollution levels and the potential health risks to nearby communities. Results: The findings reveal significant differences across the sites, with the highest pollutant concentrations in Kanaan for air (40±445.8), soil (22.18±35.64), and water (3.037±3.146), while Hamrin recorded the lowest concentrations. All sites demonstrated statistically significant differences (P &lt; 0.05). Novelty: This study provides the first comprehensive analysis of the environmental impact of waste disposal practices in Diyala, linking pollutant concentrations with specific landfill sites. Implications: The results underscore the need for improved waste management strategies, including monitoring, waste sorting, and recycling initiatives, to mitigate the negative effects on public health and the environment, particularly in areas near waste dumps. Highlights: Pollution levels vary significantly across Diyala's landfill sites. Kanaan site has the highest air, soil, and water contamination. Better waste management is needed to reduce environmental and health risks. Keywords: Municipal waste, environmental pollution, heavy metals, Diyala Governorate, landfill impact

Commuter exposure to ultrafine particles (UFPs), lung deposited surface area (LDSA), and noise in Ho Chi Minh City, Vietnam

IntroductionTransport is a main contributor to air and noise pollution, particularly in urban areas with the high number of motorized vehicles. Promoting active transport (i.e., cycling and walking) and public transport is an instrumental factor in reducing traffic-related air and noise pollution. However, commuters of these transport modes are often exposed to high air and noise pollution than other commuter groups. MethodsThe levels of exposure to UFP, LDSA, and noise during commuting of different transport modes in Ho Chi Minh City (HCMC) were measured and compared. Then, the dose of inhaled pollutants during commuting was calculated for each commuter group by considering the travel time and minute ventilation. ResultsThe level of exposure to air and noise pollution varies across transport modes. Cyclists and motorcyclists were exposed to the highest level of air and noise pollution. Motorcyclists and cyclists were exposed to the highest UFP number concentrations during their trips, 3.6*105 and 3.1*105 particles/cm3, respectively. Car commuters were exposed to the lowest air and noise pollution level, followed by bus commuters. When considering the minute ventilation and travel time, cyclists inhaled significantly higher levels of air pollution than other commuters, followed by pedestrians, motorcyclists, bus commuters, and car users. As a result, the health impacts of exposure to traffic-related air and noise pollution for active commuters could be greater than other commuter groups. ConclusionsPromoting active and public transport is a promising approach to improving air quality and reducing congestion in HCMC. Using these transport modes also has potential positive health effects on commuters through physical activities. However, active commuters are faced with the highest risk of exposure to high air and noise pollution levels. To promote active transport and public transport in HCMC, measures to reduce the level of exposure to air and noise pollution for these commuter groups are needed.

An electron paramagnetic resonance time-course study of oxidative stress in the plasma of electronic cigarette exposed rats.

The long-term consequences of electronic cigarette (Ecig) use in humans are not yet known, but it is known that Ecig aerosols contain many toxic compounds of concern. We have recently shown that Ecig exposure impairs middle cerebral artery (MCA) endothelial function and that it takes 3days for MCA reactivity to return to normal. However, the sources contributing to impairment of the endothelium were not investigated. We hypothesized that the increased levels of oxidative stress markers in the blood are correlated with impaired MCA reactivity. We used electron paramagnetic resonance (EPR) spectroscopy to examine plasma from 4-month-old male Sprague-Dawley rats that were exposed to either air (n=5) or 1h Ecig exposure, after which blood samples were collected at varying times after exposure (i.e., 1-4, 24, 48 and 72h postexposure, n=4 or 5 in each time group). The EPR analyses were performed using the redox-sensitive hydroxylamine spin probe 1-hydroxy-3-carboxymethyl-2,2,5,5-tetramethyl-pyrrolidine (CMH) to measure the level of reactive oxidant species in the plasma samples. We found that EPR signal intensity from the CM• radical was significantly increased in plasma at 1-4, 24 and 48h (P<0.05, respectively) and returned to control (air) levels by 72h. When evaluating the EPR results with MCA reactivity, we found a significant negative correlation (Pearson's P=0.0027). These data indicate that impaired cerebrovascular reactivity resulting from vaping is associated with the oxidative stress level (measured by EPR from plasma) and indicate that a single 1h vaping session can negatively influence vascular health for up to 3 days after vaping. HIGHLIGHTS: What is the central question of this study? Does the time course of oxidative stress triggered by electronic cigarette exposure follow the cerebral vascular dysfunction? What is the main finding and its importance? Electron paramagnetic resonance analysis shows that the oxidative stress induced after a single 1h exposure to electronic cigarette aerosol takes ≤72h to return to normal, which mirrors the time course for vascular dysfunction in the middle cerebral artery that we have reported previously.

Examining effects of air pollution on photovoltaic systems via interpretable random forest model

Renewable energy plays a vital role in power generation and solar photovoltaic systems due to resource availability throughout the year. This work aims to investigate the impact of air pollutants and meteorological parameters on the performance of the photovoltaic systems locally, taking into consideration the advantages of the photovoltaic power potential of the SW part of Romania, where Craiova is located (average solar radiation intensity >1350 kWh/m2/year). This study is based on a one-year dataset provided by a sensor that monitors particulate matter concentrations, volatile organic compounds, dioxide of carbon, ozone, noise, formaldehyde and three climate parameters (temperature, pressure, and relative humidity). The research methodology applies an innovative interpretable random forest model emphasising the implications of air pollution for photovoltaic systems. The proposed machine learning model was trained to predict the particulate matter level in air based on the basic environmental variable measurements. The study presents six random forest models of varying complexity, which reach the accuracy of classification for the selected problem up to 99 %, and applies the Shapley Additive Explanations technique to interpret the decision-making model. The observation regarding the highest concentration of particulate matter occurring during cold months, which typically do not align with peak solar irradiance, underscores the importance of considering various environmental factors in solar energy planning. With its practical implications, this insight offers decision-makers valuable information about the feasibility of optimising solar energy generation despite seasonal variations in air pollution levels, directly addressing their needs and concerns.

Real-time monitoring of CH4 and N2O emissions from livestock using mid-infrared external cavity quantum cascade laser absorption spectroscopy

The largest share of greenhouse gas (GHG) emissions related to livestock originates from methane (CH4) and nitrous oxide (N2O) which have a far higher influence on global warming, it is therefore necessary to accurately monitor CH4 and N2O emissions to provide theoretical and practical basis for further estimating and regulating GHG emissions from livestock and improving livestock production performance. For the purpose of sensing CH4 and N2O emissions during livestock living process in real time, an optical sensor based on continuous-wave (CW) external cavity quantum cascade laser (EC-QCL) operating at room temperature was developed. CH4 and N2O absorption lines, located around 8 μm, of the ν4 and ν1 fundamental vibrational bands, respectively, were chosen for direct absorption spectroscopy, which allows for sensitive, selective and simultaneous measurement of CH4 and N2O concentrations. Use of a Herriot multi-pass cell with an effective path-length of 100 m, 1σ (SNR = 1) limits of detection of 26.8 ppbv, 20.3 ppbv and 0.01 % for CH4, N2O and H2O vapor were achieved, respectively. Field measurement of CH4 and N2O emissions from horses has been carried out in a stable over two weeks at the Vernaelde farm in Couderkerque Branche city, France. Concentrations of CH4 and N2O up to 10 times and 1.5 times higher than their levels in the local ambient air (∼ 2.12 ppmv and ∼ 427 ppbv) were observed, respectively.

Microscopic insights into the ammonia-methanol blended combustion at high temperatures

Ammonia and methanol have a broad application prospect in the future as green renewable liquid fuels. Methanol has high reactivity and good solubility with ammonia, which is conducive to solving the dilemma of ammonia combustion. However, there are few studies on ammonia-methanol blended combustion, and the effect of blended combustion on the reaction pathways needs to be further investigated. Therefore, this study used the reaction molecular dynamics simulations to reveal the role of methanol on the ammonia combustion and emission process at the microscopic level, focusing on the effects of different fuel blending ratios and oxygen concentration in the air under stoichiometric conditions. The variation of oxidation pathways from ammonia to NO and methanol to CO under different conditions was analyzed in detail. It was found that the methanol accelerated ammonia combustion mainly through enhancing OH production, but methanol and its intermediates inhibited the initial oxidation of ammonia. When the fuel blending ratio was 0.75, the system had lower fuel-type NO production alongside a higher ammonia consumption rate under stoichiometric conditions. The crucial role of NH in the HNO formation at high-temperature ammonia oxidation conditions was revealed. The pathway of HNO + OH → NO + H2O dominated the conversion of HNO to NO in this study. Increasing the methanol content promoted the conversion of NH to HNO and the pyrolysis of HNO while inhibiting the reaction between HNO and O2. In addition, the finding indicated that the high O2 level in air can enhance the reactions between ammonia and OH radicals but inhibit the pyrolysis of CH2OH/CH3O significantly.

Modulatory Effects of Vitamin D: A Possible Approach to Mitigate Air Pollution Related Pregnancy Complications.

Approximately 99% of people on the planet breathe air that exceeds the World Health Organization's permitted threshold for pollution. South Asia is home to the world's most polluted cities. Population-based studies have suggested that women's reproductive health outcomes are worsening due to air pollution. Preeclampsia, miscarriage, gestational diabetes, high blood pressure, and unfavorable birth outcomes, including preterm birth, low birth weight, or even stillbirth are all linked to exposure to air pollution during pregnancy. It is estimated that 0.61 million deaths in India alone were related to indoor air pollution. Females frequently cook in the household using solid fuel as a primary combustion source. Women in the regions with the highest population density are disproportionately affected by high levels of poor-quality indoor air. Recently, it has been proposed that air pollution has a distinct role in the onset of vitamin D deficiency. Numerous studies have explored associations between low vitamin D level and various female reproductive health conditions since the discovery of the vitamin D receptor. It is worthy to note that some of these reproductive health conditions positively correlate with the severity of air pollution. In this study, the evidence has been synthesized on vitamin D's protective properties and dietary and pharmaceutical interventions have been discussed to show their beneficial effects in decreasing the long-term negative impacts of air pollution on women's health.

Evaluation of Particulate matter and air pollutants level in the ambient air of Bengaluru city

Background: Air pollution has been a global environmental concern, and its effects on human health in the past have played an important role. Thus, this study investigated the concentrations of particulate matter (PM10, PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO) in four distinct areas of Bengaluru over one year. Materials and Methods: It is a descriptive cross-sectional design, utilizing secondary data from the Central Pollution Control Board's National Air Quality Monitoring Programme. Data analysis was conducted using SPSS software, expressing descriptive statistics such as mean, standard deviation, and maximum concentrations. Results: The study reveals varying air quality levels, with PM10 peaking at 102 µg/m³ in Silk Broad (August 2023) and NO2 spiking in February 2023. SO2 peaks at Majestic (March 2023), while CO poses health risks, peaking in January 2023. Silk Broad shows highest PM10; Majestic has elevated NO2, SO2, and CO. Conclusion: The study reveals fluctuating air quality, with PM10 peaking at 102 µg/m³ in Silk Broad station (August 2023) and NO2 spiking in February 2023. SO2 and CO levels also vary, posing health risks, particularly at Majestic station. Regional disparities highlight the need for targeted pollution control.