Indoor Pollution Research Articles

Research on influencing factors and improvement methods for air pollution in rural houses of severe cold region of China

Self-sufficient energy system leads to high levels of indoor pollution, accompanied by fuel burning processes indoors. Many factors have potential impacts and relations among factors and indoor air pollution are complicated. Exploration on revealing the relations in rural-houses of severe cold region of China is still insufficient. This paper attempted to comprehensively explore influences of factors composed of building layout, building envelope, heating feature, outdoor climate on indoor air pollutants. Field measurement and questionnaire survey were conducted in thirty-nine villages located in Shenyang, China. Temporal data for indoor air pollutants, including PM2.5, PM10, CO2 and CO in winter were measured. For each pollutant, 51,110 pieces of data were obtained. Statistics for percentage distributions of pollutants in different concentration intervals showed that 80% of day-time was in serious pollution situation. Associations between factors and indoor air pollutions were investigated utilizing multifactorial logistic regression. The values of OR and CI showed that these factors had significant effects on four kinds of pollutants. Overall, variations of factors in the four dimensions were found to have the greatest impact on CO2 concentration. Further, the influence of different heating scenarios composed of multiple factors on indoor air pollution level were analyzed. Twenty heating scenarios were suggested for heating in rural houses of severe cold region. Time-series data of air pollutants, indoor air temperature and humidity were detrended to study the correlations while eliminating the influence of time. It was found that indoor temperature fluctuated earlier than air pollutants and thus should not be taken as the indicator of estimating fuel burning time. The research results are helpful to deepen the understanding of the influence of various factors on complex indoor environment of rural houses in severe cold region. In addition, yielded results will provide basis to formulate strategies for improving living environment of rural-house and help to eliminate the health inequities caused by poverty.

Quantification and probabilistic health risk assessment of benzene series compounds emitted from cooking process in restaurant kitchens

The formation of volatile organic compounds (VOCs) during cooking processes is a significant contributor to indoor pollution. Benzene, toluene, ethylbenzene, and xylene isomers (BTEX) are aromatic hydrocarbons emitted during various cooking styles, posing potential carcinogenic (CR) and non-carcinogenic health risks (n-CR). This study measured BTEX compound concentrations emitted from three common cooking methods (barbecuing, frying, and boiling) in eight restaurant kitchens located in Birjand city, South Khorasan province, Iran. Sampling was conducted near the inhalation zone for each cooking style. The associated risk from the measured concentrations was assessed probabilistically. The study results demonstrated that frying emitted the highest levels of B, X, and E, followed by barbecuing and then boiling. For T, barbecuing showed the highest emissions, followed by frying and boiling. Overall, barbecuing generated the most pollutants, followed by frying and boiling, respectively. This pattern was also reflected in the carcinogenic (CR) and non-carcinogenic (n-CR) risks associated with each cooking method. Among the kitchens examined, all showed significant n-CR, with only one kitchen indicating a possible risk level for CR. Sensitivity analysis highlighted that chemical concentrations were the primary factor influencing exposure in most kitchens, although staff behavior was also significant in other kitchens. The findings underscore the health risks posed to kitchen staff by cooking emissions. Government policies, interventions, and legislation aimed at restaurant owners, focusing on education and environmental health, are crucial steps to mitigate this problem. Staff awareness of inhalation risks associated with emissions and strategies to reduce exposure—including proper ventilation, modifying cooking styles, and using respiratory protective equipment—can significantly mitigate health risks.

Indoor Volatile Organic Compounds in Prefabricated Timber Buildings—Challenges and Opportunities for Sustainability

Prefabricated timber buildings offer a low-carbon approach that can help reduce the environmental impact of the building and construction sectors. However, construction materials such as manufactured timber products can emit a range volatile organic compounds (VOCs) that are potentially hazardous to human health. We evaluated 24 years (2000–2024) of peer-reviewed publications of VOCs within prefabricated timber buildings. Studies detected hazardous air pollutants such as formaldehyde, benzene, toluene, and acetaldehyde (indoor concentration ranges of 3.4–94.9 µg/m3, 1.2–19 µg/m3, 0.97–28 µg/m3, and 0.75–352 µg/m3, respectively), with benzene concentrations potentially exceeding World Health Organization indoor air quality guidelines for long/short term exposure. Most studies also detected terpenes (range of 1.8–232 µg/m3). The highest concentrations of formaldehyde and terpenes were in a prefabricated house, and the highest of benzene and toluene were in a prefabricated office building. Paradoxically, the features of prefabricated buildings that make them attractive for sustainability, such as incorporation of manufactured timber products, increased building air tightness, and rapid construction times, make them more prone to indoor air quality problems. Source reduction strategies, such as the use of low-VOC materials and emission barriers, were found to substantially reduce levels of certain indoor pollutants, including formaldehyde. Increasing building ventilation rate during occupancy is also an effective strategy for reducing indoor VOC concentrations, although with the repercussion of increased energy use. Overall, the review revealed a wide range of indoor VOC concentrations, with formaldehyde levels approaching and benzene concentrations potentially exceeding WHO indoor air quality guidelines. The paucity of evidence on indoor air quality in prefabricated timber buildings is notable given the growth in the sector, and points to the need for further evaluation to assess potential health impacts.

Consequences of Indoor Pollution in Children in Latin America.

Indoor air pollution represents a major health problem in developing countries. Common sources of contaminants include biomass fuels, dust mites, mold, and insecticides, which are frequently found in Latin American households due to cultural, geographical, and socioeconomic conditions. Additionally, tobacco consumption and e-cigarette use are both frequent in the region and represent another source of air pollution. Furthermore, agriculture plays an important role in Latin American and Caribbean economies, leading to hazardous environmental exposures for people living in rural areas. Children are more vulnerable than adults to the effects of environmental exposures because of various physiological and behavioral factors. The timing of exposure is also relevant, as the developing lungs are more susceptible during certain periods of growth, and early insults may impact future development. Exposure to indoor pollution, both prenatal and after birth, has been associated with an increased risk of health issues in children, such as growth impairment, respiratory infections, asthma, reduced lung function, and development of adult lung diseases (e.g., cancer and COPD). To understand how childhood environmental exposures affect lung development, with potential long-term consequences and increased risk of diseases later in life, is essential for developing effective prevention strategies.

Parental stress and environmental influences on children's physician-diagnosed food allergy

Previous research has linked stress and environmental factors to first-wave allergies (i.e., asthma, allergic rhinitis, and eczema), but their individual and combined effects on second-wave allergies (i.e., food allergies, including conditions such as egg, and milk allergies) remain unknown. We aim to investigate the effects of parental stress and its interaction with environmental factors on childhood physician-diagnosed food allergies (PFA). In Changsha (China), we performed a mixed cross-sectional and retrospective cohort investigation. we gather data on each preschooler's health status, parental stress, and living environment through questionnaires. Temperature and air pollutant exposures were calculated using inverse distance weighting methods. Multivariate logistic regression models were employed to examine relations pf PFA relates with parental stress, indoor and outdoor pollutants and allergens. We found that high/middle education and gross annual income were associated with total PFA (ORs [95% CI] = 1.89 [1.52–2.36] and 1.23 [1.01–1.50]) and other types of PFAs, while high psychological stress (fatigue, headache, and inattention) increased PFA risk (1.59 [1.34–1.90], 1.35 [1.18–1.55], and 1.41 [1.23–1.62]). Families experiencing higher economic stress reported higher PFA risk of blooming and non-blooming plants in first year. The PFA risk of mould and mildew stains in utero and the first year was higher in families with parental inattention. ORs of PFA due to PM2.5–10 and PM10 during the second trimester were higher in families with high parental social stress. PFA risk of PM2.5 in the late preconceptional and entire postnatal periods was higher in families with parental fatigue, headache, and inattention. We suggest parental stress independently and interplayed with indoor and outdoor environmental pollution and allergens, increases risk of childhood PFA.

Influence of Candle Emissions on Monoterpene Oxidation Chemistry and Secondary Organic Aerosol.

Candle burning is a considerable contributor to indoor pollutants, while secondary organic aerosols (SOA) from monoterpene ozonolysis represent another type. However, knowledge of the interactions of different indoor pollutants is limited. We investigated physicochemical properties of SOA generated from typical indoor chemistry of the O3/α-pinene reaction with and without the presence of particles and gases from a burning candle. Ozonolysis of α-pinene in the presence of candle gaseous emissions yielded a considerably lower particle number, larger particle sizes, and lower particle oxygen-to-carbon ratio compared with experiments without candle emissions. More nitrogen-containing organic compounds were observed in the aerosol phase with candle emissions. Furthermore, concentrations of some typical particle-phase products from the O3/α-pinene reaction (i.e., terebic acid, cis-pinic acid, and 3-methyl-1,2,3-butanetricarboxylic acid) were less abundant in the presence of candle emissions. The predicted volatility of particulate organic compounds was higher in experiments with candle emissions. The study demonstrates that candle burning can affect the chemical and physical properties of particles formed from other sources (e.g., α-pinene ozonolysis) by affecting gas-phase chemistry and gas-particle partitioning.

Perforated plate ventilation system and dynamics of infectious respiratory particle transmission

AbstractWith the removal of indoor pollutants and the assurance of air quality emerging as critical research topics, the optimization of the internal environment in offices, where people stay for extended periods, is essential for controlling the spread of infectious respiratory particles. Frequent movements of personnel and the operation of doors and windows within offices significantly impact the mechanisms of droplet transmission, warranting further investigation. This study employs computational fluid dynamics simulations to explore the droplet dispersion characteristics and pollutant removal efficiency of the simplified model of perforated plate ventilation system (PPVS) (the diameter of the air supply openings has been reasonably simplified and uniformly set to 0.02 m) in office settings, as well as the impact of dynamic door operation scenarios on droplet spread and concentrations in breathing zones. To optimize the ventilation system's pollutant removal efficiency, airflow velocities (2.86, 3.18, and 5.00 m/s) are varied, with simulations conducted at the optimal velocity of 3.18 m/s. The effects of continuous door operations, door‐opening directions (towards the office and towards the isolation room), and opening speeds (π/4, π/6, π/8, and π/10 rad/s) are also examined, revealing significant impacts on droplet spread. Results indicate that PPVS effectively reduces indoor pollutant concentrations at all tested airflow velocities, with the optimal speed identified as 3.18 m/s. Additionally, door‐opening direction and speed can significantly influence droplet spread. Opening doors towards isolation rooms at smaller angles (less than 30°) effectively reduces droplet concentrations in personnel breathing zones, thereby mitigating the risk of droplet transmission. Faster door‐opening speeds also contribute to lower droplet concentrations in these zones. This innovative study explores the impacts of PPVS and dynamic door operation dynamics on droplet transmission during respiratory disease outbreaks, providing valuable theoretical insights and technical support for disease prevention and indoor air quality improvement.

Indoor Air Quality Monitoring System with High Accuracy of Gas Classification and Concentration Prediction via Selective Mechanism Research.

The efficacy of sensors, particularly sensor arrays, lies in their selectivity. However, research on selectivity remains notably obscure and scarce. In this work, indoor pollutants (C7H8, HCHO, CH4, and NO2) were chosen as the target gas. Following the screening of six oxides from previous work, temperature-programmed desorption/reduction experiments were conducted to delve into the origins of selectivity. The results explicate the superiority of NiO in detecting toluene and unveil the distinctive NO2 sensing mechanism of WO3 sensors. Based on the sensor array comprising these oxides, it can clearly detect low concentrations of C7H8 (S = 1.6 to 50 ppb), HCHO (S = 1.4 to 50 ppb), and NO2 (S = 3.3 to 50 ppb), which satisfies the requisites of indoor air monitoring. Meanwhile, three machine learning models (Extreme Gradient Boosting, Support Vector Machine, and Back Propagation Neural Network) are employed for gas classification. The classification accuracies of these models are 95.45%, 100%, and 100%, while the R2 values of the concentration prediction are 99.65%, 94.9%, and 98.04%, respectively, indicating the rationality of material selection. Furthermore, it can still achieve relatively high accuracy in gas classification (94.12%) and concentration prediction (89.36%), even for gas mixtures of four gases. Finally, an indoor air quality monitoring system is developed, which enables real-time monitoring of indoor gas quality through the Internet of Things.

A Numerical and Experimental Study to Compare Different IAQ-Based Smart Ventilation Techniques

Maintaining indoor environmental quality in residential buildings is essential for occupants’ comfort, productivity, and health, with effective mechanical ventilation playing a key role in removing or diluting indoor pollutants. A two-week experimental campaign was conducted in an apartment in Lyon, France, known for its poor urban air quality, assessing temperature, relative humidity, CO2, and PM2.5 concentrations. A model verification study was performed to compare experimental measurements against numerical modeling in the living room and bedroom, leading to errors in the accuracy of the sensors. In addition, this study also investigates the impact of different ventilation strategies on indoor air quality. This research evaluates a baseline mechanical exhaust-only ventilation approach with constant air volume against two innovative smart ventilation approaches: mechanical exhaust-only ventilation with humidity control and mechanical exhaust-only ventilation with room-level CO2 and humidity control. A key contribution of this research is the novel coupling of multizone simulation models (DOMUS and CONTAM) with a CFD tool to refine pressure coefficients on the building façade, which enhances the accuracy of indoor air quality predictions. The smart ventilation strategies showed improvements, including a 20% reduction in CO2 concentration and a 5% reduction in the third-quartile PM2.5 concentration, highlighting their effectiveness in enhancing ventilation and pollutant dilution. This research provides valuable insights into advanced ventilation strategies and modeling techniques in urban environments.

Innovative Antifungal Photocatalytic Paint for Improving Indoor Environment

Indoor air quality (IAQ) has emerged as a global concern due to the increasing presence of indoor pollutants, which have been shown to negatively impact public health. These pollutants stem from various household activities and the materials used in buildings. Previous studies have explored several methods to improve IAQ, including gas adsorption, ozonation, non-thermal plasma, and photocatalytic oxidation (PCO). However, these methods often have drawbacks, such as generating secondary pollutants or incurring high costs. This study examines the effectiveness of photocatalytic paint, which is activated by visible light, in controlling fungal growth to enhance IAQ. Experimental results showed that when applied to grown fungi, the photocatalytic paint led to a significant reduction in the size of fungal fibers, as observed through scanning electron microscopy (SEM). Furthermore, exposure to the photocatalytic paint reduced the size of fungal hyphae by 37% after 85 h. The paint produced by adding 1 mL photocatalytic paint to 10 mL commercial paint demonstrated high efficiency in fungi removal, i.e., reducing the weight of fungi by approximately 45% within 3 h. These results highlight the potential of photocatalytic paint to significantly inhibit fungal growth, offering a promising solution for improving indoor environments.

Vocs pollution and respiratory exposure in commercial and residential underground parking garages

The indoor air quality in Underground Parking Garages (UPGs) has deteriorated significantly, primarily due to the high concentrations of particulate matter and volatile organic compounds (VOCs) emitted by idling or low-speed motor vehicles. However, the compositional characteristics and respiratory exposure to VOCs in UPGs have not been quantitatively analyzed. To establish a method for investigating the respiratory exposure to VOCs among different populations in UPGs, a three-dimensional dynamic diffusion model of indoor pollutants was developed based on monitoring data from 116 components in various UPGs in a large city in northern China. The results indicated that air pollution in underground spaces poses significant health risks to workers and children. Furthermore, a comprehensive approach is essential for improving ventilation capacity and air quality in underground transportation spaces.

The health impact of PM2.5 and O3 in Beijing modified by infiltration factors from 2014 to 2022.

PM2.5 and O3 are significant threats to the health of residents and modern residents spend more than 80% of their time indoors, so quantifying indoor exposure of residents has a positive influence on formulating policies and improving health indicators. Analysis of monitoring data shows a consistent decrease in the annual average concentration of outdoor PM2.5 in Beijing from 90.1 to 30.4μg/m3, and the equivalent human exposure concentration also declined from 55.2 to 18.6μg/m3 modified by infiltration factors from 2014 to 2022, while during the peak season, the average value of O3-8h concentration in Beijing has consistently remained between 159.3 and 225.3μg/m3; the equivalent human exposure concentration remained between 64.7 and 92.3μg/m3 modified by infiltration factors from 2014 to 2023. The equivalent exposure concentration is calculated by weighting the concentration of indoor and outdoor pollutants, the proportion of indoor and outdoor activity time of the population, and the permeability coefficient of outdoor pollutants into the room, so as to quantify the actual concentration of pollutants exposed to the human body in a certain time. Previous studies have primarily focused on the impact of annual changes in pollutant concentrations on health estimates, often neglecting indoor concentrations and behavior patterns. This limitation should be addressed. Therefore, this study utilized equivalent human exposure concentration and AirQ + , the authoritative software released by the World Health Organization (WHO), to evaluate quantitatively the impact of PM2.5 and O3 on the health of Beijing residents by combining pollutant concentration, annual population, and mortality of various diseases and other indicators to enhance the credibility of the study. The number of deaths related to PM2.5 has decreased from 28,182 people in 2014 to 10,250 people in 2022 (age ≥ 30). The number of premature deaths in 2022 was only 36.4 percent of that in 2014 and was decreasing by 1992 per year. The number of deaths related to O3 varies between 550 and 3358 people. Lowering PM2.5 and O3 concentrations can effectively reduce natural premature death as well as cardiovascular and respiratory diseases caused by air pollution. The government should persist in enhancing the regulation of PM2.5 and accord significance to the oversight of O3. Concurrently, there is a need to reinforce the cooperative regulation addressing both PM2.5 and O3.

Air pollution and under-5 child mortality: linking satellite and IPUMS-DHS data across 41 countries in South Asia and Sub-Saharan Africa

BackgroundDespite progress, under-five mortality remains high, especially in Sub-Saharan Africa and South Asia, where around 13,400 children die daily. Environmental pollutants, including PM2.5 from outdoor air and household air pollution, significantly contribute to these preventable deaths.MethodsThis cross-country study combined satellite data with 113 surveys from the IPUMS-DHS dataset (1998–2019) to examine under-five child mortality in 41 developing countries. The integration of Global Annual Particulate Matter with a diameter of 2.5 micrometres or less (PM2.5) Grids from Socioeconomic Data and Applications Center (SEDAC) and geospatial data from the DHS Program enabled a focused analysis of the association between indoor and outdoor air pollution, particularly PM2.5, and child mortality rates using both logistic and multilevel logistic regression models, as well as estimating Population Attributable Fractions (PAF) to quantify the mortality burden attributable to these pollutants.ResultsOutdoor air pollution, measured by a one standard deviation increase in PM2.5, significantly increased the risk of child mortality (Odds Ratio [OR]: 1.14; 95% Confidence Interval [CI]: 1.10–1.18; p < 0.001). Moderate and high household air pollution exposure also heightened this risk, with increases of 37% (OR: 1.37; 95% CI: 1.24–1.53; p < 0.001) and 40% (OR: 1.40; 95% CI: 1.26–1.56; p < 0.001), respectively, compared to no exposure. Multilevel models (Models 5a and 10a) produced similar estimates to standard logistic regression, indicating robust associations. Additionally, Population Attributable Fraction analysis revealed that approximately 11.9% of under-five mortality could be prevented by reducing ambient PM2.5 exposure and 12.0% by mitigating household air pollution. The interaction between indoor and outdoor pollution revealed complex dynamics, with moderate and high household exposure associated with a reduction in mortality risk when combined with PM2.5. Geographical disparities were observed, with stronger correlations between outdoor air pollution and child mortality in Africa compared to Asia, and more pronounced impacts in low-income countries. However, household air pollution had stronger association with child mortality in Africa and lower- and middle-income countries.ConclusionsOur findings could serve as a guide for policy development aimed at reducing under-five mortality, ultimately contributing to the attainment of the Sustainable Development Goal (SDGs).

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.

Democratizing air: A co-created citizen science approach to indoor air quality monitoring

Indoor air quality (IAQ) is crucial for public health, yet many remain unaware of indoor pollutants. Although Citizen Science has enhanced outdoor air quality understanding, its application to IAQ remains underexplored. This study introduces a new co-creation methodology that addresses key limitations in existing IAQ monitoring practices by integrating value-sensitive design principles and a ‘facilitated emergence’ paradigm. Through three co-creation workshops, we engaged multiple stakeholders in every stage, from problem definition to data interpretation. We employed adaptive facilitation strategies to effectively balance power dynamics among stakeholders, ensuring inclusive decision-making and mitigating potential biases. Our 30-day data collection campaign provided real-time measurements of Particulate Matter (PM) concentrations. Analysis revealed several locations with Indoor/Outdoor (I/O) PM2.5 ratios close to or above 1, uncovering hidden IAQ complexities and emphasizing the need for localized monitoring. We showed how citizen-generated data can improve spatial resolution, detecting local variations missed by official networks. Feedback from the co-creation workshops demonstrated shifts in participants’ perceptions regarding IAQ, accountability, and their role in environmental decision-making, moving from passive awareness to active engagement. Our findings demonstrate how this value-sensitive and community-driven bottom-up approach can enhance air quality assessment, inform targeted IAQ management strategies, and empower citizens in environmental health decisions.

Highly selective detection of ppb-level formaldehyde realized by regulating the surface chemisorbed oxygen of Ga-doped In2O3 microspheres

Formaldehyde is a ubiquitous indoor pollutant. Developing metal oxide semiconductors gas sensors for selective ppb-level formaldehyde detection is challenging. Therefore, developing gas sensors that can selectively detect indoor formaldehyde at ppb levels is important. In this study, outer-walled thin sheet-like microspheres of Ga-doped In2O3 (GaxIn2-xO3, x = 0, 0.1, 0.2, 0.3, and 0.4) were fabricated using a facile two-step synthetic method. The Ga0.3In1.7O3 based sensor shows the response (556 ± 25) to 100 ppm formaldehyde at 80 °C, which is around 6.5 times that of the pure In2O3 based sensor at 90 °C. Furthermore, it has fast response time (< 3 s), excellent selectivity (SFormaldehyde/SEthanol = 160, SFormaldehyde/SAcetone = 267), good stability (at least 60 days), and ultra-low limit of detection (10 ppb) for formaldehyde at 80 °C. The improved formaldehyde sensing performance of Ga0.3In1.7O3 microspheres is attributed to the optimization of surface chemisorbed oxygen, which is caused by Ga doping regulating the Fermi level of In2O3 as well as an increase in the specific surface area.

Bleaching Agents: A Review of Their Utilization and Management

Exposure to disinfectants, cleansers, and bleaching chemicals irritates the eyes, respiratory systems, and skin, triggering asthma and allergic rhinitis symptoms. Bleach, as the major constituent of cleansers, when used improperly or mixed with other indoor cleaning agents, produces harmful halogenated volatile organic compounds. This manuscript assesses the influence of excessive exposure to disinfectants, including bleaching agents, when used against infectious conditions related to SARS-COVID-19 and its management. The use and impact of different bleaching agents in cleansing and their associated problems have been analyzed and presented in this review. This analysis focuses on the conventional and post-pandemic approach towards bleaches. Usage of bleaching agents increased by a staggering 20.4% and 16.4% from January to March 2020 compared to the same period in 2018 and 2019. Mounting use of bleaching agents during the COVID-19 pandemic resulted in negative health effects like asthma, eye irritation, and skin allergies. An approximately 42% rise in poisoning cases, including a few deaths, has been associated with exposure to harmful chemicals involving bleaches during the recent pandemic. Bleaching agents are the primary sources of hazardous indoor pollutants; therefore, despite their importance in disinfection, their utility must be substantiated based on legal guidelines, disposal, and remedial measures. Thus, conducting future occupational exposure assessment studies for bleach hazard management is crucial.

Implications of Traditional Cooking on Air Quality and Female Health: An In-Depth Analysis of Particulate Matter, Carbon Monoxide, and Carbon Dioxide Exposure in a Rural Community

Indoor air pollution, particularly in rural communities, is a significant health determinant, primarily due to the prevalence of traditional cooking practices. The WHO estimates 4.3 million annual deaths related to household air pollution. This study quantifies indoor pollutants and assesses health impacts and perceptions regarding traditional cooking. Using Extech air quality monitoring equipment, the study measured particulate matter (PM), carbon monoxide (CO), and carbon dioxide (CO2) in 48 rural homes. A survey of 39 women gathered insights on their use of wood for cooking and perceptions of air quality. This dual approach analyzed both environmental and social dimensions. Findings showed fine particulate matter (0.3, 0.5, 1.0, and 2.5 μm) exceeded safety limits by threefold, while coarser particulates (5.0 and 10 µm) were concerning but less immediate. CO levels were mostly acceptable, but high concentrations posed risks. CO2 levels indicated good ventilation. Survey responses highlighted reliance on wood and poor air quality perceptions demonstrating little awareness of health risks. Common symptoms included eye discomfort, respiratory issues, and headaches. The study emphasizes the need for interventions to reduce exposure to indoor pollutants and increase awareness of health risks to encourage cleaner cooking practices in rural communities.

Indoor moss biomonitoring proving construction-related pollution load from outdoors

Indoor pollution load in an office environment was investigated during ongoing construction works in the vicinity using the wet moss biomonitoring technique. Monitoring boxes were placed inside eight offices with mechanical ventilation located on three floors and with four different orientations to outdoor construction works for 8 weeks. Samples were collected every two weeks for two months, and the concentrations of selected elements: Al, As, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Pb, Si and Zn were determined. Total deposition (composition, number and size of particles) was determined in the samples too. Correlation analysis complemented by Principle Component Analysis (PCA) was performed using a compositional approach. Concentrations correlated significantly among crustal elements and among road dust elements. PCA identified three groups of elements – representing construction dust, traffic origin and indoor origin, while those associated with construction dust had the highest contribution. The elevation (floor) affected the composition of the samples the most, the orientation to the pollution sources was secondary. Construction dust was most dominant on the 1st floor; samples from the sheltered sites were negatively associated with construction dust elements; here, the finest particles were also observed. Starting at 6 weeks of exposure, construction dust elements started to dominate in samples. Construction dust is a serious pollution problem, and its infiltration from the outdoors is apparent even in mechanical-ventilated indoor environments. Moss indoor monitoring technique was proven to be a suitable cost-effective alternative to automatic air samplers in determining the outdoor-originating pollution loads indoors.

Mesostructured manganese oxides for efficient catalytic oxidation of CO, ethylene, and propylene at mild temperatures: Insight into the role of crystalline phases and physico-chemical properties

Removing pollutants for indoor air purification is a key point to ensure the health and well-being of people in confined environments. This work aims to provide new insight into the development of promising manganese oxide catalysts. The effects of different crystalline phases (MnO2 and Mn2O3) and the role of redox properties and structural defects were investigated to abate indoor pollutants at mild temperatures. These materials were extensively characterized through complementary techniques and catalytic tests were performed to oxidize 100 ppm of CO, ethylene, or propylene. The most promising catalyst was obtained through solution combustion synthesis, achieving total removal at 118, 222, and 172 °C, respectively, with the highest oxidation rate (2.41, 0.88, and 2.47 μmolg−1s−1) and lowest activation energy (50, 32, and 45 kJmol−1) for the three molecules. The synergy between crystalline phases enhanced the catalytic performance and their distribution in the structure was a crucial parameter affecting the number of structural defects.