Source Of Indoor Air Pollution Research Articles

Healthy air for healthy minds

Abstract Background The adverse health effects from exposure to air pollution is increasingly known. A recent report shows that at least 95% of the world’s population breathe air containing dangerous levels of pollutants. According to estimates from the World Health Organization (WHO), ambient air pollution is related to 4.2 million deaths every year. Less is known about the association between indoor air (especially particulate matter 2.5 and volatile organic compounds (VOC) pollution and mental health conditions. Many sources of indoor air pollution exist, such as pressed wood products, pesticides, secondhand smoke, stoves, heaters, overcrowding and fireplaces. Aims We aim to synthesize knowledge on the effects of particulate matter 2.5 in indoor air and mental health conditions. Methods We systematically reviewed the association of indoor air pollution with mental health conditions using the databases Pubmed and EMBASE. Results Exposure to indoor air pollutants is associated with increased anxiety and depression and less cognitive performance. These results are robust; however, the impact of PM2.5 is larger for less-educated and female respondents. Females cook with solid fuels and biomass more often. Physical exposure and gender factors overlap in the exposure to indoor air pollutants. Discussion Poor indoor air quality should be part of a comprehensive assessment of factors influencing mental health and cognition. Neuroinflammation might explain the effects of poor air on mental health and cognition. Further research is needed to combine research on the social determinants of mental health and the effects of indoor air. Studies in different settings such as home, work, and hospitals are needed to better understand the specific exposures of indoor air pollution and mental health conditions in different population groups.

Association between pets and dry eye symptoms: A Chinese national-based study

BackgroundPet-derived allergens are another source of indoor air pollution which could affect human health. However, the association between pet ownership and the risk of dry eye symptoms (DES) remains to be elucidated. MethodsWe conducted a nationwide cross-sectional survey among Chinese residents aged over 12 years from June 20, 2022 to August 31, 2022. The Ocular Surface Disease Index-6 (OSDI-6) questionnaire was utilized to evaluate the presence of DES. Multivariable logistic regression models were used to analyze the associations between pet ownership and DES. Subgroup analyses were conducted based on sex, age, residence and affective disorders, and sensitivity analysis by excluding participants with major ocular diseases. The interactions between pet ownership and other risk factors on DES were explored in the additive scale by calculating the synergy index (SI). ResultsA total of 21,916 subjects replied to the questionnaire. The prevalence of DES was 43.6 % (95 % confidence interval (CI), 43.0 %–44.3 %). Pet ownership was significantly associated with increased risk of DES (Odds ratio (OR): 1.13, 95%CI: 1.05–1.21), especially among the elderly (OR: 1.28, 95%CI: 1.09–1.51) and urban residents (OR: 1.13, 95%CI: 1.04–1.24). The individual effect of allergic rhinitis on DES was 2.59 (95%CI: 1.27–5.53), while the joint effect of pets and allergic rhinitis was 5.26 (95%CI: 1.20–36.74), suggesting a synergistic interaction with a SI of 2.48 (95%CI: 0.25–24.39). Furthermore, the interaction analysis also indicated a synergistic interaction between pet ownership and low health literacy with a SI of 1.12 (95%CI: 0.66–1.87). ConclusionPet ownership was identified as a risk factor for DES. The synergistic interaction of pet ownership and allergic rhinitis suggests shared mechanisms between DES and allergic conditions.

Numerical simulation of particles distribution of environmental tobacco smoke (ETS) and its concentration in a closed environment

Humans are frequently exposed to various chemical hazards, with smoking being a significant source of indoor air pollution. This pollution is particularly pronounced in environments such as smoking rooms, conference halls, cafes, and coffee houses. This study focuses on analyzing the concentration, distribution, and behavior of emitted particles from both mainstream and sidestream smoke in a controlled smoking room environment. A critical aspect of the research is the consideration of the thermal plume generated by the smoker's body, particularly around the breathing zone, which plays a crucial role in the dispersion and inhalation of pollutants. To conduct this analysis, a computational fluid dynamics approach was employed, incorporating a displacement ventilation (DV) system integrated with a detailed surface mesh model of a standing manikin. A Lagrangian approach was utilized to track the particle paths, considering factors such as particle size, density, and initial velocity. This approach was complemented by an Eulerian method to simulate the complex airflow patterns within the smoking room, accounting for turbulent flow and temperature variations. The integration of these methods provides a comprehensive understanding of both the macroscopic and microscopic behaviors of smoke particles. The motion equations governing the particles incorporated several forces, including inertial drag force, viscous drag force, buoyancy force, and gravitational force. Additionally, the study examined the interaction between thermal plumes and smoke particles, particularly how temperature gradients around the body affect particle dispersion and concentration. The study meticulously evaluated the distribution and volume average of respirable suspended particles (RSPs) and nicotine by analyzing a plane opposite to the breathing zone of both heated and unheated manikins. It was observed that the thermal plume generated by the temperature gradient around the body could significantly alter the flow field of both sidestream and mainstream smoke between puff periods. The simulation results demonstrated that the thermal plume increased the concentration of RSPs in the breathing zone, highlighting a critical exposure pathway for smokers and nonsmokers alike. A significant increase of approximately 70% in the nicotine concentration is due to the thermal plume. The concentration of nicotine peaks at approximately 0.003 mg/m3 by the third second in smoker#1's (6 smokers' position) breathing zone. Specific configurations of the DV system showed varying efficiencies in reducing pollutant concentrations, emphasizing the need for targeted ventilation strategies. In a chamber with six smokers, researchers found that the time required for suspended particles to reach a cleaning ratio, considering the dynamics of particle movement due to smoking activity, was approximately 184 s per puff.

Evidence-driven indoor air quality improvement: An innovative and interdisciplinary approach to improving indoor air quality.

Indoor air pollution is a recognized emerging threat, claiming millions of lives annually. People are constantly exposed to ambient and indoor air pollution. The latest research shows that people in developed countries spend up to 90% of their time indoors and almost 70% at home. Although impaired IAQ represents a significant health risk, it affects people differently, and specific populations are more vulnerable: children, the elderly, and people with respiratory illnesses are more sensitive to these environmental risks. Despite rather extensive research on IAQ, most of the current understanding about the subject, which includes pollution sources, indoor-outdoor relationships, and ventilation/filtration, is still quite limited, mainly because air quality monitoring in the EU is primarily focused on ambient air quality and regulatory requirements are lacking for indoor environments. Therefore, the EDIAQI project aims to improve guidelines and awareness for advancing the IAQ in Europe and beyond by allowing user-friendly access to information about indoor air pollution exposures, sources, and related risk factors. The solution proposed with EDIAQI consists of conducting a characterization of sources and routes of exposure and dispersion of chemical, biological, and emerging indoor air pollution in multiple cities in the EU. The project will deploy cost-effective/user-friendly monitoring solutions to create new knowledge on sources, exposure routes, and indoor multipollutant body burdens. The EDIAQI project brings together 18 organizations from 11 different European countries that provide interdisciplinary skills and expertise in various fields, including environmental science and technology, medicine, and toxicology, as well as policy design and public engagement.

The impact of surfaces on indoor air chemistry following cooking and cleaning.

Cooking and cleaning are common sources of indoor air pollutants, including volatile organic compounds (VOCs). The chemical fate of VOCs indoors is determined by both gas-phase and multi-phase chemistry, and can result in the formation of potentially hazardous secondary pollutants. Chemical interactions at the gas-surface boundary play an important role in indoor environments due to the characteristically high surface area to volume ratios (SAVs). This study first characterises the VOC emissions from a typical cooking and cleaning activity in a semi-realistic domestic kitchen, using real-time measurements. While cooking emitted a larger amount of VOCs overall, both cooking and cleaning were sources of chemically reactive monoterpenes (peak mixing ratios 7 ppb and 2 ppb, respectively). Chemical processing of the VOC emissions from sequential cooking and cleaning activities was then simulated in a kitchen using a detailed chemical model. Results showed that ozone (O3) deposition was most effective onto plastic and soft furnishings, while wooden surfaces were the most effective at producing formaldehyde following multi-phase chemistry. Subsequent modelling of cooking and cleaning emissions using a range of measured kitchen SAVs revealed that indoor oxidant levels and the subsequent chemistry, are strongly influenced by the total and material-specific SAV of the room. O3 mixing ratios ranged from 1.3-7.8 ppb across 9 simulated kitchens, with higher concentrations of secondary pollutants observed at higher O3 concentration. Increased room volume, decreased total SAV, decreased SAVs of plastic and soft furnishings, and increased wood SAV contributed to elevated formaldehyde and total peroxyacetyl nitrates (PANs) mixing ratios, of up to 1548 ppt and 643 ppt, respectively, following cooking and cleaning. Therefore, the size and material composition of indoor environments has the potential to impact the chemical processing of VOC emissions from common occupant activities.

Association between Outdoor and Indoor Air Pollution Sources and Atopic Eczema Among Preschool Children in South Africa

Association between Outdoor and Indoor Air Pollution Sources and Atopic Eczema Among Preschool Children in South Africa

Impacts of daily household activities on indoor particulate and NO2 concentrations; a case study from oxford UK

This study explores indoor air pollutant (PM1, PM2.5 and NO2) concentrations over a 15-week period during the COVID-19 pandemic in a typical suburban household in Oxford, UK. A multi-room intensive monitoring study was conducted in a single dwelling using 10 air quality sensors measuring real-time pollutant concentrations at 10 second intervals to assess temporal and spatial variability in PM1, PM2.5 and NO2 concentrations, identify pollution-prone areas, and investigate the impact of residents' activities on indoor air quality. Significant spatial variations in PM concentrations were observed within the study dwelling, with highest hourly concentrations (769.0 & 300.9 μg m−3 for PM2.5, and PM1, respectively) observed in the upstairs study room, which had poor ventilation. Cooking activities were identified as a major contributor to indoor particulate pollution, with peak concentrations aligning with cooking events. Indoor NO2 levels were typically higher than outdoor levels, particularly in the kitchen where a gas-cooking appliance was used. There was no significant association observed between outdoor and indoor PM concentrations; however, a clear correlation was evident between kitchen PM emissions and indoor levels. Similarly, outdoor NO2 had a limited influence on indoor air quality compared to kitchen activities. Indoor sources were found to dominate for both PM and NO2, with higher Indoor/Outdoor (I/O) ratios observed in the upstairs bedroom and the kitchen. Overall, our findings highlight the contribution of indoor air pollutant sources and domestic activities to indoor air pollution exposure, notably during the COVID-19 pandemic when people were typically spending more time in domestic settings. Our novel findings, which suggest high levels of pollutant concentrations in upstairs (first floor) rooms, underscore the necessity for targeted interventions. These interventions include the implementation of source control measures, effective ventilation strategies and occupant education for behaviour change, all aimed at improving indoor air quality and promoting healthier living environments.

Study on the deposition characteristics of fine particles at local components in air conditioning ventilation ducts

Air conditioning ventilation ducts are widely used in contemporary buildings. The change of airflow direction in the ducts local components can easily lead to the deposition of particles, which can easily form a secondary source of indoor air pollution and have an adverse effect on human health. Based on this, this paper utilizes the existing experimental data to validate the numerical simulation. The Reynolds stress turbulence model combined with the method of enhanced wall function was used to investigate the deposition characteristics of fine particles in different local components. For the first time, local deposition rates and deposition hotspots were proposed to analyze the simulation results. The results show that the local deposition rate of the particles with a particle size of 1μm do not differ much on each wall surface, and the particles are deposited more uniformly on each wall at the local components, with a difference of less than 10 %, and the maximum local deposition rate is on the outer wall of the local components. When the particle size is larger than 10μm, the local deposition rate on the outer wall of the local component increases significantly, with a maximum increase of 23.3 % (compared to 5μm particles), and the maximum local deposition rate increases slowly with increasing air velocity, with a maximum increase of less than 8 %. The effect of increasing particle size on the maximum local deposition rate is much greater than the increase in air velocity. With the increase of air velocity and particle size, the deposition hotspots of both the 90° bend and the T-type tee duct migrate to the middle of the wall, and the deposition hotspots of the 4-way duct migrate to the inside of the wall.

Multi-sensor monitoring and analysis of indoor pollutant emissions in response to laser cutter operating conditions

This study analyzed pollutant emissions from laser cutters used in modeling in a laboratory, which can have harmful effects on indoor air quality and health. Four conditions were tested: material thickness, laser cutter strength, minimum strength per thickness, and air purifier level. Four pollutants were analyzed: PM2.5, HCHO, VOCs, and CO2. The study found that the emissions of PM2.5, HCHO, and VOCs increased with paperboard thickness, while CO2 emissions were not significant. PM2.5 was more affected by laser cutting strength, while HCHO and VOCs were more affected by paperboard thickness. Additionally, we analyzed the PM2.5 emission rates based on the thickness of the paperboard and the laser cutting strength. Therefore, emission rates based on thickness and laser cutting strength ranged from 7275 to 18,783 μg/min. The air purifier significantly reduced PM2.5 but not HCHO and VOCs. To reduce these gaseous pollutants, combining mechanical ventilation or using an air purifier with a filter that adsorbs HCHO and VOCs is effective. This study highlights the importance of considering laser cutters as a potential source of indoor air pollutants and implementing measures to mitigate their harmful effects.

Assessing Household Awareness of Indoor Air Pollution in Cagayan de Oro City: Implications for Health Promotion

Background & Aim: Indoor air pollution is a significant health threat, yet public awareness remains low, particularly in regions like the Philippines. This study assessed household awareness of indoor air pollution sources in a barangay in Cagayan de Oro City. Using the Health Promotion Model by Nola Pender and the Environmental Theory by Florence Nightingale, it sought to understand factors influencing awareness and inform health programs addressing indoor air pollution in the community. Methods & Materials: This study used a descriptive correlational design to explore how demographic factors influence awareness of indoor air pollution sources in a barangay in Cagayan De Oro City. Surveys, translated into the local language and validated through pilot testing, were administered to 264 randomly selected respondents. Statistical analyses, including T-tests and ANOVA, were conducted to assess associations between demographic variables and awareness levels. Results: Significant differences were observed in respondents' awareness levels of indoor air pollution sources across age groups, with middle-aged individuals demonstrating the highest awareness. Females exhibited consistently higher awareness compared to males across all pollution sources. Educational attainment influenced awareness levels, with postgraduates showing the highest awareness. Conclusion: The study revealed significant correlations between demographic factors and respondents' awareness of indoor air pollution sources. Age, gender, and educational attainment influence awareness levels, motivating individuals to prioritize proper ventilation for health preservation. Recommendation: Clinical practitioners should prioritize health education programs targeting middle-aged individuals, females, and those with higher educational attainment levels in addressing indoor air pollution awareness, emphasizing the importance of proper ventilation practices for health preservation and promoting healthier indoor environments in communities

A study of neurological functions in construction work painters

BackgroundPainters are constantly exposed to organic solvents containing volatile organic compounds (VOCs), a primary source of indoor air pollution. Prolonged exposure to solvents generates significant health repercussions on pulmonary and neurological functioning. Few studies have assessed the neurological function of unorganized sector painters objectively, especially in developing nations. The current research evaluates the effects of organic solvents on neurological functions in painters working in unorganized sectors like construction sites in Chennai. MethodsA validated questionnaire was used to assess solvent-exposed neurological symptoms in full-time painters (n = 75) aged 25–55, stratified by years of exposure (≤10 years, >10 years). A subset of 35 painters underwent bilateral median nerve motor and sensory nerve conduction studies. Personal exposure monitors measured VOC concentration during the painting processes. ResultsToluene and benzene concentrations were greater in paint scraping. 47% of painters reported neurological symptoms, and those with >10 years of experience had a higher AOR (95%CI): 3.4 (1.3, 9.6). 13% had diplopia, 18% had ocular discomfort. Painters with more than 10 years of experience had longer motor and sensory onset latency of the left median nerve, as well as decreased bilateral sensory conduction velocities (Right median nerve: 53.8 ± 13.9 vs 64.2 ± 5.2; Left median nerve: 55.75 ± 6.5 vs 64.3 ± 6.2). ConclusionPaint emits toluene, a major solvent. The impact of occupational exposure to organic solvents on neurological functions has been observed to exhibit a progressive deterioration over time. Health awareness and strict protective measure legislation are needed to reduce morbidity and mortality in these unorganized sectors.

Assessment of the Bacteriological Properties of Indoor Dust in some Classrooms of Delta State University of Science and Technology, Ozoro

The bacteriological properties of indoor dust in some classrooms of the Delta State University of Science, Ozoro was examined with a view to identify any possible source of pollution of classroom indoor air quality; measurement of microbial load of classroom dust sample and to compare findings of selected locations as a means to determine high air polluted areas. This was done by the collection of dust samples from classrooms table and chair surfaces. It was observed that the amount of bacteria available in classrooms differ based on activities in and around the classrooms. Bacteria isolates indicated the presence of pathogen associated with disease such as Bacillus sp; Staphylococcus sp; Micrococcus sp. of indoor air pollution exist and this is identified as open dump practice birthing more microbial cells which are transported through air and poor sanitation practice around and within the classrooms. Contamination of sample was observed for dust at different locations with the bacteria count seen to be higher at sample C (1.8x102cfu/m3) and lower in sample D (0.2x102cfu/m3). Staphylococcus sp dominated all the locations that were analyzed while Micrococcus sp. only occurred in site C. This is because poor environmental sanitation is observed at certain classrooms in addition to shattered classroom windows given an ease of access of dust flow indoor. It can be concluded that only a minimal sources of indoor air pollution exist and hence only a small amount of bacteria is present. In spite of this, prevalence of such practices is likely to promote the growth of more microbial cells.

Independent and Joint Effects of Prenatal Incense-Burning Smoke Exposure and Children's Early Outdoor Activity on Preschoolers' Obesity.

Incense burning is a significant source of indoor air pollution in many Asian regions. There is emerging evidence that maternal prenatal exposure to incense-burning smoke may be a risk factor for childhood obesity. We aimed to extend this new line of research by investigating the independent and joint effect of incense-burning smoke exposure, and children's outdoor activity in early life, on preschoolers' obesity. A total of 69,637 mother-child dyads were recruited from all kindergartens in the Longhua District of Shenzhen, China. Information on sociodemographic characteristics, maternal exposure to incense-burning smoke (IBS) during pregnancy, and frequency and duration of outdoor activity at the age of 1-3 years was collected by a self-administered questionnaire. In addition, the heights and weights of the children were measured by the research team. Logistic regression models and cross-over analyses were conducted to investigate the independent and combined effects of maternal exposure to incense-burning smoke during pregnancy and children's early outdoor activity on obesity in preschoolers. We found that prenatal exposure to incense-burning smoke increased the risk of the presence of obesity in preschoolers' (AOR = 1.13, 95% CI = 1.03-1.23). Additionally, lower frequencies (<3 times/week) or shorter durations (<60 min/time) of outdoor activity from the age of 1-3 years were significantly associated with the presence of obesity, with AORs of 1.24 (95% CI =1.18-1.32) and 1.11 (95% CI = 1.05-1.17), respectively. Furthermore, the cross-over analysis showed that prenatal exposure to IBS combined with a lower frequency of early outdoor activity (AOR = 1.47, 95% CI = 1.31-1.66) or a shorter duration of outdoor activity during ages of 1-3 years (AOR = 1.22, 95% CI = 1.07-1.39) increased the risk of obesity in preschoolers. Finally, additive interactions between prenatal exposure to IBS and postnatal outdoor activity on obesity were identified. Our study indicates that maternal exposure to incense-burning smoke during pregnancy and early lower postanal outdoor activity may independently and jointly increase the risk of obesity among preschoolers.

Stenotrophomonas maltophilia contributes to smoking-related emphysema through IRF1-triggered PANoptosis of alveolar epithelial cells

Cigarette smoke (CS), the main source of indoor air pollution and the primary risk factor for respiratory diseases, contains chemicals that can perturb microbiota through antibiotic effects. Although smoking induces a disturbance of microbiota in the lower respiratory tract, whether and how it contributes to initiation or promotion of emphysema are not well clarified. Here, we demonstrated an aberrant microbiome in lung tissue of patients with smoking-related COPD. We found that Stenotrophomonas maltophilia (S. maltophilia) was expanded in lung tissue of patients with smoking-related COPD. We revealed that S. maltophilia drives PANoptosis in alveolar epithelial cells and represses formation of alveolar organoids through IRF1 (interferon regulatory factor 1). Mechanistically, IRF1 accelerated transcription of ZBP1 (Z-DNA Binding Protein 1) in S. maltophilia-infected alveolar epithelial cells. Elevated ZBP1 served as a component of the PANoptosome, which triggered PANoptosis in these cells. By using of alveolar organoids infected by S. maltophilia, we found that targeting of IRF1 mitigated S. maltophilia-induced injury of these organoids. Moreover, the expansion of S. maltophilia and the expression of IRF1 negatively correlated with the progression of emphysema. Thus, the present study provides insights into the mechanism of lung dysbiosis in smoking-related COPD, and presents a potential target for mitigation of COPD progression.

IJCM_159A: Descriptive study on determinants of indoor air pollution and its perceived impact on health among residents of urban field practice area of a tertiary care hospital

Background: Indoor air pollution is the presence of unwanted substances in the indoor at concentration toxic to health. According to WHO, around 3.8 million deaths occur due to indoor air pollution every year. Very few studies have addressed indoor air pollution. Thus, this study aimed at determinants of indoor air pollution and its perceived impact on health among residents. Objectives: 1. To study the determinants of indoor air pollution among residents of urban field practice area of a tertiary care hospital. 2. To study the perceived impact of indoor air pollution on health among residents of urban field practice area of a tertiary care hospital. Methodology: A community-based cross-sectional study conducted among 105 households of urban field practice area of a tertiary care hospital during August 2023 to October 2023. Data collection was done using predesigned pre tested interview schedule which consists of sociodemographic characteristics, sources of indoor air pollution, checklist of contributory factors of air pollutants and related symptoms/diseases. Results: About 45.7% households had second hand smoke in house. Smoke from the neighbourhood troubled 38% respondents. 33.3% households had IAP owing to vehicular exhausts. 75.2% houses were having absence of cross ventilation and 68.5% houses were poorly ventilated. Also, 60.9% houses reported overcrowding. About 53.3% complained of having at least one symptom of IAP. Conclusion: Majority of the households were exposed to IAP due to second hand smoke, neighborhood smoke while absence of cross ventilation accented it. Efforts to address IAP should be made to protect residents from adverse health effects.

In-Utero exposure to potential sources of indoor air pollution and umbilical cord blood leukocyte telomere length

Indoor air pollution (IAP) has been associated with various adverse health effects. However, the evidence regarding such an association with leukocyte telomere length (LTL) in cord blood samples is still scarce. Therefore, the present study aimed to assess the relationship between exposure to indicators of IAP and LTL in umbilical cord blood samples. This cross-sectional study was based on 188 mother-newborn pairs who participated in our study between 2020 and 2022 in Isfahan, Iran. Umbilical LTL was measured by quantitative real-time polymerase chain reaction (qRT-PCR) technique. Linear mixed-effect models were used to assess the relationship between IAP indicators and umbilical LTL, adjusted for relevant covariates. The median (interquartile range (IQR)) of umbilical LTL was 0.92 (0.47). In fully adjusted models, frequency of using degreasing spray during pregnancy (times per month) (β = −0.047, 95% CI:0.09, −0.05, P-value = 0.02), using air freshener spray during pregnancy (β = −0.26, 95% CI: −0.5, −0.02, P-value = 0.03) and frequency of using insecticides during pregnancy (times per month) (β = −0.025, 95% CI: −0.047, −0.003, P-value = 0.02) were significantly associated with shorter umbilical LTL. There was a positive significant relationship between the frequency of using cleaning spray during pregnancy (times per month) with umbilical LTL (β = 0.019, 95% CI: 0.005, 0.033, P-value = 0.01). Furthermore, the direct connection of the parking with home and the frequency of using barbecue (times per week) were marginally associated with shorter umbilical LTL. For other indicators of IAP, we did not observe any statistically significant associations. Overall, this study suggested a negative association between prenatal exposure to IAP during pregnancy and umbilical LTL.

Correlation gas chromatography and two-dimensional volatility basis methods to predict gas-particle partitioning for e-cigarette aerosols.

E-cigarette aerosols contain a complex mixture of harmful and potentially harmful chemicals. Once released into the environment, they evolve and become new sources of indoor air pollutants that could pose a significant threat to both users and non-users. However, current understanding of the physicochemical properties of e-cigarette aerosol constituents that govern gas-particle partitioning in the atmosphere is limited, making it difficult to estimate the health risks associated with exposure. Here, we used correlation gas chromatography (C-GC) and two-dimensional volatility basis set (2D-VBS) methods to determine the vapor pressures and volatility for commonly reported toxic and irritating e-cigarette aerosol constituents. The vapor pressures of target compounds at 298 K were estimated from the Antoine-type linear relationship between the vapor pressure of reference standards and their retention times. Our C-GC results showed an overall positive correlation (R = 0.84) with estimates using the EPI (Estimation Programs Interface) Suite. The volatility calculated by 2D-VBS correlates well with the calculated vapor pressure from both C-GC (R = 0.82) and EPI Suite (R = 0.85). The volatility distribution also indicated fresh e-cigarette aerosol constituents are mainly more volatile organic compounds. Our case study revealed that low-vapor-pressure compounds (e.g., σ-dodecalactone, γ-decalactone, and maltol) become enriched in the e-cigarette aerosols within 2 hours following vaping emissions. Overall, these findings demonstrate the applicability of the C-GC and 2D-VBS methods for determining the physiochemical properties of e-cigarette aerosol constituents, which can aid in assessing the dynamic chemical composition of e-cigarette aerosols and exposures to vaping emissions in indoor environments.

Association between Outdoor and Indoor Air Pollution Sources and Atopic Eczema among Preschool Children in South Africa.

The objective of the study was to investigate the association between outdoor and indoor air pollution sources and atopic eczema among preschool children in South Africa. A cross-sectional design, following the International Study of Asthma and Allergies in Childhood (ISAAC) Phase III protocol, was applied. The study was conducted in Mabopane and Soshanguve Townships in the City of Tshwane Metropolitan Municipality in Gauteng, South Africa. A total population of 1844 preschool children aged 7 years and below participated in the study; 1840 were included in the final data analysis. Data were analyzed using multilevel logistic regression analysis. The prevalence of eczema ever (EE) and current eczema symptoms (ESs) was 11.9% and 13.3%, respectively. The use of open fires (paraffin, wood, or coal) for cooking and heating increased the likelihood of EE (OR = 1.63; 95% CI: 0.76-3.52) and current ESs (OR = 1.94; 95% CI: 1.00-3.74). Environmental tobacco smoke (ETS) exposure at home increased the likelihood of EE (OR = 1.66; 95% CI: 1.08-2.55) and current ESs (OR = 1.61; 95% CI: 1.07-2.43). Mothers or female guardians smoking cigarettes increased the likelihood of EE (OR = 1.50; 95% CI: 0.86-2.62) and current ESs (OR = 1.23; 95% CI: 0.71-2.13). The use of combined building materials in homes increased the likelihood of EE, and corrugated iron significantly increased the likelihood of current ESs. The frequency of trucks passing near the preschool children's residences on weekdays was found to be associated with EE and current ESs, with a significant association observed when trucks passed the children's residences almost all day on weekdays. Atopic eczema was positively associated with exposure to outdoor and indoor air pollution sources.

Assessment of air pollution emitted during cooking using biomass and cleaner fuels in the Shiselweni region of Eswatini (Swaziland)

In Eswatini, 62.3% of households still rely on solid fuel for cooking, especially wood (61.8%). Smoke emissions during biomass burning remain the primary source of indoor air pollution, comprising pollutants detrimental to health. This study provides a quantitative exposure assessment of fuels used in the Shiselweni region with the objectives of monitoring the carbon monoxide (CO) and carbon dioxide (CO2) concentrations during cooking events and evaluating cancer and noncancer risks due to exposure to particulate-bound polycyclic aromatic hydrocarbons (PAHs) during cooking events among cooking personnel in households that cook indoors by burning biomass. Real-time CO, CO2, and particulate matter (PM) monitoring was performed in seventeen kitchens during cooking events across the Shiselweni region using different cooking methods: biomass in open fires and stoves, liquefied petroleum gas (LPG), and electric stoves. PM2.5, PM10, and CO exceeded indoor exposure guidelines for biomass fuel-related homesteads. Particulate PAH intake concentrations were evaluated, and biomass fuel users exhibited high cancer risks and low embryo survival chances due to particulate PAH exposure. The average total cost of reducing the incremental lifetime cancer risk (ILCR) and hazard quotient (HQ) to acceptable levels was lower when shifting from biomass to LPG stoves than when shifting to electric stoves.Graphical abstract

Indoor Air Sources of Outdoor Air Pollution: Health Consequences, Policy, and Recommendations: An Official American Thoracic Society Workshop Report.

Indoor sources of air pollution worsen indoor and outdoor air quality. Thus, identifying and reducing indoor pollutant sources would decrease both indoor and outdoor air pollution, benefit public health, and help address the climate crisis. As outdoor sources come under regulatory control, unregulated indoor sources become a rising percentage of the problem. This American Thoracic Society workshop was convened in 2022 to evaluate this increasing proportion of indoor contributions to outdoor air quality. The workshop was conducted by physicians and scientists, including atmospheric and aerosol scientists, environmental engineers, toxicologists, epidemiologists, regulatory policy experts, and pediatric and adult pulmonologists. Presentations and discussion sessions were centered on 1) the generation and migration of pollutants from indoors to outdoors, 2) the sources and circumstances representing the greatest threat, and 3) effective remedies to reduce the health burden of indoor sources of air pollution. The scope of the workshop was residential and commercial sources of indoor air pollution in the United States. Topics included wood burning, natural gas, cooking, evaporative volatile organic compounds, source apportionment, and regulatory policy. The workshop concluded that indoor sources of air pollution are significant contributors to outdoor air quality and that source control and filtration are the most effective measures to reduce indoor contributions to outdoor air. Interventions should prioritize environmental justice: Households of lower socioeconomic status have higher concentrations of indoor air pollutants from both indoor and outdoor sources. We identify research priorities, potential health benefits, and mitigation actions to consider (e.g., switching from natural gas to electric stoves and transitioning to scent-free consumer products). The workshop committee emphasizes the benefits of combustion-free homes and businesses and recommends economic, legislative, and education strategies aimed at achieving this goal.