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Abstract\nNOVELTY STATEMENTFormaldehyde is an organic volatile compound and a commonly used chemical in various construction materials thus causing dwellers to be exposed to it inside a building. Its remediation from indoor air has been carried out through various techniques where potted plants and living walls are at the front foot. It is necessary to study plants under various conditions for their efficiency. We selected three plant species Epipremnum aureum, Chlorophytum comosum, and Spathiphyllum wallisii non-native of Bahrain. These plants were tested under normal conditions in a sealed fumigation box where formaldehyde concentration was kept ∼3 ppm, CO2 ∼ 450 ppm, light intensity 1000 Lx (equal to 13.5 µmol.m−2.s−1), irrigated with tap water. Analysis of Variance (ANOVA) statistical method was performed to test the significant differences of purification efficiencies of the tested indoor plants against HCHO. In addition, the statistical method was used to test the significant difference, if any, of the plants to CO2 emission because of absorbing HCHO. The physical health of plants and their short-term remediation ability reveals that all plants exhibited up to 70% remediation potential and tolerance to remediate the target chemical. It is evident that the impact of local environmental factors on the plants is negligible.Epipremnum aureum, Chlorophytum comosum, and Spathiphyllum wallisii are non-native plants available in Bahrain for decorative purposes.Their efficiency against formaldehyde under local indoor environment was studied for the first time.Under normal conditions the plant proved to be sufficiently tolerant toward normal conditions. The efficiency in normal soil system is very good.The efficiency of the three species was mutually compared, statistical modeling reveal that they are significantly close to each other in terms of formaldehyde remediation to purify ambient air.Epipremnum aureum, Chlorophytum comosum, and Spathiphyllum wallisii are non-native plants available in Bahrain for decorative purposes.Their efficiency against formaldehyde under local indoor environment was studied for the first time.Under normal conditions the plant proved to be sufficiently tolerant toward normal conditions. The efficiency in normal soil system is very good.The efficiency of the three species was mutually compared, statistical modeling reveal that they are significantly close to each other in terms of formaldehyde remediation to purify ambient air. [ABSTRACT FROM AUTHOR]

Residents of long-term care facilities are particularly vulnerable to communicable diseases. Low-cost interventions to increase air exchange rates (AERs) may be useful in reducing the transmission of airborne communicable diseases between long-term care residents and staff. In this study, carbon dioxide gas was used as a tracer to evaluate the AER associated with the implementation of low-cost ventilation interventions. Under baseline conditions with the room's door closed, the mean AER was 0.67 ACH; while baseline conditions with the door open had a significantly higher mean AER of 3.87 ACH (p < 0.001). Subsequently opening a window with the door open increased mean AER by 1.49 ACH (p = 0.012) and adding a fan in the window further increased mean AER by 1.87 ACH (p < 0.001). Regression analyses indicated that the flow rate of air entering through the window, both passively and through the use of a fan, was significantly associated with an increase in AER (p < 0.001). These results indicate that low-cost interventions that pull outside air into resident rooms were effective in improving the air exchange rates in these facilities. While implementation of these interventions is dependent on facility rules and isolation requirements of residents with airborne communicable diseases, these interventions remain viable options for long-term care facilities to improve resident room ventilation without requiring costly ventilation system upgrades. [ABSTRACT FROM AUTHOR]

Indoor air quality is an important aspect of buildings, including libraries where various activities take place. This study aimed to investigate indoor air quality in different microenvironments in a library in Thailand. The indoor air monitoring was conducted in a library for 4 microenvironments: reading, librarian, cafe shop, and photocopy shop zone. Respiratory dust and bioaerosols were analyzed using NIOSH methods 0600, and 0800, respectively. Air movements were determined using an anemometer. Particulate matters (PM) were measured using DustTrak; carbon dioxide and comfort parameters were measured using Q-TRAK with 30-minute average for 8 hours. The results showed that the means of respiratory dust, PM10, PM4, PM2.5 in all zones met the standard, however, temporary variation revealed that PM4 and PM2.5 exceeded the standard in the afternoon. Fungal concentration was above 500 cfu/m3 in the photocopy shop zone where the highest %RH and the lowest air movement were found. Carbon dioxide concentrations in the cafe shop zone exceeded 1,000 ppm. The real-time measurements showed significant strong correlations between the different PM sizes, moderate correlations between %RH and temperature, and CO2 and PM10. The findings suggest that preventive and corrective measures should be implemented to improve indoor air quality in the library. [ABSTRACT FROM AUTHOR]

In Malaysia, chemical management in workplaces is managed under the Occupational Safety and Health Act 1994. Hence, the introduction of the Occupational Safety and Health (Use and Standards of Exposure of Chemicals Hazardous to Health) Regulations 2000 has strengthened the chemical management level in workplaces, including higher academic institutions. The introduction of chemical health risk assessment through the regulation required management to conduct the assessment at workplaces. Poor levels of Indoor Air Quality (IAQ) in chemical laboratories may also cause discomfort among workers when there is sick building syndrome in laboratories. IAQ is managed through the Industry Code of Practice on Indoor Air Quality 2010. Although both are different in method and approach, both are meant to ensure the workers' safety and comfort. This study is aimed to investigate the need to integrate both chemical health risk assessment and IAQ assessment in laboratories to ensure optimum safety levels among workers. [ABSTRACT FROM AUTHOR]

Wildfire activity is increasing around the world, concurrent with climate change, and mitigation strategies for protecting vulnerable populations are desperately needed. Because inhaled particles are deleterious to respiratory health, particularly among older adults with co-morbidities, we engaged maintenance personnel working in long term care facilities located in the Western US. Our objective was to identify opportunities to build resilience during wildfire smoke events. We implemented a virtual workshop that addressed wildfire smoke health impacts as well as strategies to assess and maintain indoor air quality. A total of 24 maintenance personnel attended the virtual workshop and 14 participated in a quantitative survey. Workshop attendees found value in the material and there was enthusiasm for educational resources and enhancing indoor air quality. Four months later, four maintenance staff participated in a follow-up interview. Our qualitative assessment revealed the following themes: awareness and prioritization, application of knowledge, barriers, and educational resources. Access to real-time actionable air quality data was a consistent feature across these themes. Maintenance personnel could play a key role in a facility's ability to prepare for and respond to wildfire smoke events, and this study highlights potential challenges and opportunities to involving them in resilience building strategies. [ABSTRACT FROM AUTHOR]

Indoor air quality and respiratory health have always been an area of prime interest across the globe. The significance of low-cost air quality sensing and indoor public health practices spiked during the pandemic when indoor air pollution became a threat to living beings, especially human beings. Problem Definition: Indoor respiration-associated diseases are hard to diagnose if they are due to indoor environmental conditions. A major challenge was observed in establishing a baseline between indoor air quality sensors and associated respiratory diseases. Methods: In this work, 10,000+ articles from top literature databases were reviewed using six bibliometric analysis methods (Lorenz Curve of Citations, Hirch's H-Index, Kosmulski's H2-Index, Harzing's Hl-Norm-Index, Sidoropolous's HC-Index, and Schrieber's HM-index) to formulate indoor air quality sensor and disease correlation publication rubrics to critically review 482 articles. Results: A set of 152 articles was found based on systematic review parameters in six bibliometric indices for publications that used WHO, NIH, US EPA, CDC, and FDA-defined principles. Five major respiratory diseases were found to be causing major death toll (up to 32%) due to five key pollutants, measured by 30+ low-cost sensors and further optimized by seven calibration systems for seven practical parameters tailored to respiratory disease baselines evaluated through 10 cost parameters. Impact: This review was conducted to assist end-users, public health facilities, state agencies, researchers, scientists, and air quality protection agencies. [ABSTRACT FROM AUTHOR]

Air quality in school environments is of particular interest due to the significant amount of time children spend in these settings. Children, being a particularly sensitive demographic, are exposed to various pollutants at school or kindergarten. In this regard, our studies have focused on monitoring the concentrations of three main categories of pollutants: VOCs (volatile organic compounds), VICs and PM (particulate matter). We conducted two experimental campaigns in seven classrooms within public educational institutions. The average concentration values of TVOC (total volatile organic compounds) ranged from 554 µg/m3 to 2518 µg/m3, of CO2 from 1055 ppm to 2050 ppm, of NH₃ (Ammonia) from 843.2 µg/m3 to 1403.4 µg/m3, of PM2.5 from 25.1 µg/m3 to 89.9 µg/m3, and of PM10 from 63.7 µg/m3 to 307.4 µg/m3. In most instances, the registered values exceeded the limit values set by national or international regulations. Furthermore, this study highlights the significant impact of a heat recovery ventilation system in improving indoor air quality by substantially reducing the levels of CO2 and PM. However, it also underscores the need for further measures to more efficiently reduce TVOC concentrations. The aim of our paper was to enhance the understanding of pollution levels in school environments, increase awareness of the importance of indoor air quality, and highlight the adverse effects of polluted air on the health of occupants. [ABSTRACT FROM AUTHOR]

Background: Acute viral bronchiolitis is the most common reason for hospitalization of infants in the USA. Infants hospitalized for bronchiolitis are at high risk for recurrent respiratory symptoms and wheeze in the subsequent year, and longer-term adverse respiratory outcomes such as persistent childhood asthma. There are no effective secondary prevention strategies. Multiple factors, including air pollutant exposure, contribute to risk of adverse respiratory outcomes in these infants. Improvement in indoor air quality following hospitalization for bronchiolitis may be a prevention opportunity to reduce symptom burden. Use of stand-alone high efficiency particulate air (HEPA) filtration units is a simple method to reduce particulate matter ≤ 2.5 µm in diameter (PM2.5), a common component of household air pollution that is strongly linked to health effects. Methods: BREATHE is a multi-center, parallel, double-blind, randomized controlled clinical trial. Two hundred twenty-eight children < 12 months of age hospitalized for the first time with bronchiolitis will participate. Children will be randomized 1:1 to receive a 24-week home intervention with filtration units containing HEPA and carbon filters (in the child's sleep space and a common room) or to a control group with units that do not contain HEPA and carbon filters. The primary objective is to determine if use of HEPA filtration units reduces respiratory symptom burden for 24 weeks compared to use of control units. Secondary objectives are to assess the efficacy of the HEPA intervention relative to control on (1) number of unscheduled healthcare visits for respiratory complaints, (2) child quality of life, and (3) average PM2.5 levels in the home. Discussion: We propose to test the use of HEPA filtration to improve indoor air quality as a strategy to reduce post-bronchiolitis respiratory symptom burden in at-risk infants with severe bronchiolitis. If the intervention proves successful, this trial will support use of HEPA filtration for children with bronchiolitis to reduce respiratory symptom burden following hospitalization. Trial registration: NCT05615870. Registered on November 14, 2022. [ABSTRACT FROM AUTHOR]

Depression and anxiety carry an important public health burden. Indoor air pollution is associated with depression and anxiety. Ventilation can reduce the concentration of indoor air pollution and improve indoor air quality. This study explored the relationship between indoor ventilation frequency and depression and anxiety in older adults using the data from the 2018 Chinese Longitudinal Healthy Longevity Survey. Compared with older people with low indoor ventilation frequency, those with high indoor ventilation frequency had 51% lower odds of depression (OR = 0.49 , 95% CI: 0.43 to 0.57) and 37% lower odds of anxiety (OR = 0.63 , 95% CI: 0.43 to 0.91), and those with intermediate indoor ventilation frequency had 35% lower odds of depression (OR = 0.65 , 95% CI: 0.56 to 0.75) and 45% lower odds of anxiety (OR = 0.55 , 95% CI: 0.37 to 0.82). The results were similar across the seasons. However, there were sex, age, lifestyle, and cooking fuel use-specific differences in these associations. The findings emphasize that high ventilation frequency may be conducive to improving mental health in older adults, especially women, the old elder, nonsmokers, nondrinkers, and those who do not exercise and cooked at home. [ABSTRACT FROM AUTHOR]

Indoor air pollution remains a major concern, with formaldehyde (HCHO) a primary contributor due to its long emission period and associated health risks, including skin allergies, coughing, and bronchitis. This study evaluated the adsorption performance and economic efficiency of various adsorbents (biochar, activated carbon, zeolites A, X, and Y) selected for HCHO removal. The impact of thermal treatment on adsorbent regeneration was also assessed. The experimental apparatus featured an adsorption column and HCHO concentration meter with an electrochemical sensor designed for adsorption analysis. Zeolite X exhibited the highest adsorption performance, followed by zeolite A, zeolite Y, activated carbon, and biochar. All adsorbents displayed increased HCHO removal rates with an extended length/diameter (L/D) ratio of the adsorption column. Zeolite A demonstrated the highest economic efficiency, followed by zeolite X, activated carbon, zeolite Y, and biochar. Higher L/D ratios improved economic efficiency and prolonged the replacement cycle (the optimal timing for adsorbent replacement to maintain high adsorption performance). Sensitivity analysis of adsorbent regeneration under varying thermal treatment conditions (150, 120, and 80°C) and durations (60, 45, and 30 min) revealed minimal changes in adsorption efficiency (±3%). The results indicated the potential of adsorbent regeneration under energy-efficient thermal treatment conditions (80°C, 30 min). In conclusion, this study underscores the importance of a comprehensive assessment, considering factors such as adsorption performance, replacement cycle, economic efficiency, and regeneration performance for the selection of optimal adsorbents for HCHO adsorption and removal. Implications: This study underscores the importance of adsorption technology for the removal of formaldehyde and similar volatile organic compounds (VOCs), highlighting the potential of alternative adsorbents, such as environmentally friendly biochar, in addition to traditional strategies, such as activated carbon and zeolites. Our findings demonstrate the feasibility of adsorbent regeneration under energy-efficient thermal treatment conditions. These results hold promise for improving indoor air quality, reducing environmental pollutants, and enhancing responses to air contaminants like fine dust and VOCs. [ABSTRACT FROM AUTHOR]

In 2019, a domestic raw coal ban (RCB) was introduced in Ulaanbaatar, Mongolia. Coal-briquettes have since been promoted in Ger district households, however implications for carbon monoxide (CO) exposure remains uncertain. We obtained 48-hour indoor CO concentrations in 23 Ger district households and compared these to 10 raw-coal households. Information on household characteristics, fuel use behaviour and stove venting practices was collected by survey. Mean 48-hour CO concentrations in coal-briquette households was 6.1 ppm (range 1.5–35.8 ppm) with no signfiicant differences by household, stove or venting factors. Peak time-weighted average CO concentrations exceeded WHO Indoor Air Quality guidelines in 9 (39%) households; with all surpassing the 8-hour guideline (>8.6 ppm); 3(13%) the 24-hour guideline (>6 ppm) and 2(9%) the 1-hour guideline (>30 ppm). Median CO levels were significantly lower in coal-briquette compared to raw coal households (p = 0.049). Indoor CO reduction was associated with RCB implementation although hazardous levels persist in this setting. [ABSTRACT FROM AUTHOR]

Measuring the systemic impact of major public health emergencies on the light industry and preventing various uncertain future external risks have become the key challenges to ensuring the stability of the light industry. This paper takes the occurrence of major public health emergencies as the background and focuses on environmental issues such as air pollution and indoor air quality degradation during emergencies. And to explore the multiscale impact of major public health emergencies on the light industry, typical light industry subsectors, and light industry enterprises. The findings of our study reveal that major public health emergencies have a negative impact on the light industry, particularly in the form of a short-term decline in exports, which tends to converge in the long run. Further, it is also revealed that there is heterogeneity in the impact on environmentally sensitive industries, labor-intensive industries, and others. At the microfirm level, major public health emergencies have shown a negative effect, especially the recent pandemic, which has a longer duration and a wider reach. Through multiscale research, this paper provides policy suggestions to improve the macrogovernance mechanism and risk prevention system for the light industry. [ABSTRACT FROM AUTHOR]

The creation of a welcoming hospital atmosphere is necessary to improve patient wellbeing and encourage healing. The goal of this study was to examine the variables affecting hospitalised patients' comfort. The study procedure included a thorough search of the Web of Science and Scopus databases, as well as the use of software analytic tools to graphically map enormous literature data, providing a deeper understanding of the linkages within the literature and its changing patterns. Insights from a range of disciplines, including engineering, psychology, immunology, microbiology, and environmental science, were included into our study using content analysis and clustering approaches. The physical environment and the social environment are two crucial factors that are related to patient comfort. The study stress the need of giving patient comfort a top priority as they heal, especially by tackling indoor air pollution. Our research also emphasises how important hospital care and food guidelines are for improving patient comfort. Prioritising patients who need specialised care and attention, especially those who have suffered trauma, should be the focus of future study. Future research in important fields including trauma, communication, hospital architecture, and nursing will be built on the findings of this study. To enhance research in these crucial areas, worldwide collaboration between experts from other nations is also advised. Although many studies stress the significance of patient comfort, few have drawn conclusions from a variety of disciplines, including medicine, engineering, immunology, microbiology, and environmental science, the most crucial issue of thoroughly researching the improvement of patient comfort has not been addressed. Healthcare workers, engineers, and other professions will benefit greatly from this study's investigation of the connection between hospital indoor environments and patient comfort. [ABSTRACT FROM AUTHOR]

Simple Summary: Human exposure to pollutants in indoor environments is a relevant health concern. Long-term monitoring data in indoor environments are largely missing due to a lack of adequate measuring devices. Biomonitoring (the use of living organisms to identify/assess potential hazardous exposure to chemicals and their effects) can provide useful information on indoor air quality and effects. Given their ability to intercept pollutants from the atmosphere, lichens and mosses are commonly used as outdoor biomonitors of atmospheric pollution by potentially toxic elements. Their application in indoor environment is recent but represents a promising output of the scientific research. In this review, indoor biomonitoring studies carried out using mosses and lichens have been compared, and critical issues and open matters have been underlined, as well as future perspectives related to their fruitful application in indoor environments. This review highlights the peculiarities of each study and the need for the development of shared harmonised protocols. Biomonitoring in indoor environments is a recent application, and so far, indoor air quality (IAQ) has been investigated only in a few cases using photosynthesising biomonitors. On the whole, 22 studies have been selected and reviewed, being specifically focused on the assessment of IAQ using biomonitors, such as lichens (9 papers), mosses (10), or their combination (3). In general, indoor samples face an altered light regime, ventilation, and a reduced hydration, which should be taken into consideration during the design and implementation of indoor monitoring. This review highlights critical issues (and some solutions) related to sample devitalisation (moss), hydration during exposure, preparation of the exposure device (mostly lichen and moss bags), duration of the exposure, post-exposure treatments, assessment of the vitality of the samples, as well as data elaboration and interpretation. This review evidences the feasibility and usefulness of lichen/moss monitoring in indoor environments and the need to develop standardised protocols. [ABSTRACT FROM AUTHOR]

Particulate matter (PM) pollution is a crucial environmental issue. Considering its adverse health impacts, especially on children's immune systems, Korean regulations require annual PM2.5 measurements in daycare centers. Therefore, we developed a low-cost PM2.5 sensor calibration model for measuring the indoor PM concentrations in daycare centers using long short-term memory (LSTM) algorithms. Moreover, we trained the model to predict the PM2.5 based on temperature and humidity, and optimized its hyperparameters. The model achieved a high accuracy and outperformed traditional calibration methods. The optimal lookback period was 76, which led to a high calibration performance with root mean and mean squared errors, a coefficient of determination, and mean absolute errors of 3.57 and 12.745, 0.962, and 2.7, respectively. The LSTM model demonstrated a better calibration performance than those of the linear (r2 = 0.57) and multiple (r2 = 0.75) linear regression models. The developed calibration model provided precise short-term measurement values for the optimal management of indoor PM concentrations. This methodology can be applied to similar environments to obtain new learning and hyper-parameters. Our results will aid in improving the accuracy of low-cost sensors for measuring indoor PM concentrations, thereby providing cost-effective solutions for enhancing children's health and well-being in daycare centers and other multiuse facilities. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM), often referred to as 3D printing, is an emerging technology with a wide range of industrial applications and process typologies. Although the release of metal nanoparticles as by-products could occur, occupational exposure limits and cogent safety standards are not currently available due to the novelty of the technology. To support the definition of benchmarks, this study aims to provide a preliminary comparison between the nanoparticle release patterns of laser metal deposition, adopting different feedstocks, namely, metal wire and metal powder. The monitored device is a university research setup, and the work presents the results of two different processes with AISI 316 L as a feedstock in powder and wired form, respectively. The monitoring confirmed the outcomes of previous studies, with a high release of nanoparticles from the powder head on the device (average 138,713 n/cm3 during printing, with maximum values exceeding 106 n/cm3). Moreover, the results show a significant concentration of nanoparticles with a wire head during the printing phase (average release of 628,156 n/cm3 with a maximum of 1,114,987 n/cm3) and pauses (average of 32,633 n/cm3 and a maximum of 733,779 n/cm3). The monitored values during pauses are particularly relevant since no personal protection equipment was used in the wire processes and the operators could access the printing room during pauses for device interventions, thus being exposed to significant nanoparticle concentrations. This study presents a preliminary evaluation of the potential exposure during laser metal deposition while implementing different technologies and provides evidence for defining effective operational safety procedures for the operators. [ABSTRACT FROM AUTHOR]

Satisfying indoor air quality in public environments has become essential in cities. In the present study, indoor PM2.5, CO2, NO2, SO2, nicotine, and BTEX have been assessed in 12 categories of public places. The highest average concentrations of PM2.5, NO2, and SO2 were observed in waterpipe cafés (233, 29.6, and 5.1 µg/m3), whereas the lowest concentrations were found in health clubs and hospitals, respectively. Moreover, indoor BTEX concentration varied from 69.5 µg/m3 (passenger terminals) to 1739.2 µg/m3 (elderly care centers). Given nicotine, the highest concentrations were found in waterpipe cafés, ranging from approximately 11.0 to 50 µg/m3. The mean hazard quotient (HQ) and Hazard Index (HI) for benzene, toluene, ethylbenzene, and xylene were calculated in all types of public environments, and results showed that the amount of HQ and HI in none of the places was more than 1. Furthermore, the lifetime cancer risk (LTCR) exceeded the guideline threshold in hospitals, restaurants, elderly care centers, passenger terminals, movie theaters, and beauty salons. The findings of our study indicate that the indoor air quality in most public settings within Tehran city is not acceptable and necessitates appropriate management. These findings underscore the importance of monitoring indoor air quality and implementing effective strategies to mitigate exposure to air pollutants. [ABSTRACT FROM AUTHOR]

Background: Surgical smoke can be a hazard because e it contains toxic gases with carcinogenic effects that may threaten health. This study aims to determine the effect of surgical smoke containing toxic chemicals on indoor air quality and examine employees' physical symptoms in the operating room. Method: The study was conducted in the operating room between June 2020 and July 2020. In the study, 45 air samples were taken before, during, and after surgery using the active sampling method. Nineteen employees working in the operating room were asked about their physical complaints and their throat cultures were taken before and after surgery. These results were compared with those of the employees working in internal units. Results: The Total Volatile Organic Compounds value at the time of surgery was significantly higher (p ≤ 0.05). Benzene concentrations remained constantly high (p ≤ 0.05) throughout the surgery, exceeding the limit values. Other VOCs (Volatile Organic Compounds) were significantly higher during surgery and remained below the limit values (p ≤ 0.05). When compared in terms of open and laparoscopic surgery, no difference between VOC concentrations was observed (p ≤ 0.05). The physical symptoms of the surgical team increased during the operation, and they experienced more complaints of tearing, burning in the eyes, hair odor, nausea, and cough than those working in the internal units (e.g., internal medicine, dermatology; (p ≤ 0.05). Conclusions: Surgical smoke was an important contaminant for indoor air quality in the operating room. [ABSTRACT FROM AUTHOR]

Clothing can absorb fine particulate pollutants from the atmosphere outdoors and then release them after entering the room in a form similar to three-handed smoke. In this study, the experimental site in Zhengzhou, a typical city with heavy pollution in central China, was used to investigate the adsorption and diffusion patterns of three different fabrics of polyester, polyester-cotton, and cotton clothing for fine particle pollutants, to guide people's behavior patterns and indoor air distribution, and to reduce indoor pollution exposure. The results showed that when garments of three different fabrics were exposed to moderate and heavy PM2.5 pollution for 1 h, 2 h, and 3 h, respectively, and then transferred to the diffusion chamber, polyester always released the highest PM2.5 concentration to indoor air during the same release cycle, followed by cotton and polyester-cotton. In addition, the concentration of indoor air pollutants will be periodically affected by the diffusion of fine particulate adsorbed by clothing fabrics. With the increase in outdoor pollution and exposure duration, the indoor PM2.5 concentration takes longer to stabilize at certain levels after the clothing is transferred to the indoor side. Finally, the comparison of natural ventilation experiments proved that it is not feasible to rely solely on natural ventilation to improve the influence of clothing pollution sources on indoor air quality. [ABSTRACT FROM AUTHOR]

Indoor air quality plays a key role in assessing people's quality of life, as a large proportion of people spend up to 22 hours a day indoors and people are exposed to indoor air almost all day long [1]. People in developed countries spend much more time indoors. Recently, employers are paying more and more attention to ensuring the well-being of employees, as it affects the quality and productivity of their work [2, 3]. Ensuring an appropriate working environment on the part of employers ensures both sustainable social and economic links. Well-being can be affected by various parameters of the indoor environment, in addition to the microclimate, they can be: lighting, noise level, and various odors. However, one of the primary indicators of comfort or discomfort in an indoor environment is thermal comfort or discomfort [4]. Gas stations were chosen as place for measurements because they are considered dangerous for several reasons: gas station territory is potentially hazardous with a high environmental risk and explosion hazard. Working shifts and nights is also considered undesirable for human health as it disrupts the biological rhythms in the human body [5]. In such circumstances, the indoor microclimate and air parameters play a very important role, as spending long hours in inappropriate microclimatic conditions is likely to lead to various long-term health problems for the workers. [ABSTRACT FROM AUTHOR]

The topic of indoor air pollution has yet to receive the same level of attention as ambient pollution. We spend considerable time indoors, and poorer indoor air quality affects most of us, particularly people with respiratory and other health conditions. There is a pressing need for methodological case studies focusing on informing households about the causes and harms of indoor air pollution and supporting changes in behaviour around different indoor activities that cause it. The use of indoor air quality (IAQ) sensor data to support behaviour change is the focus of our research in this paper. We have conducted two studies—first, to evaluate the effectiveness of the IAQ data visualisation as a trigger for the natural reflection capability of human beings to raise awareness. This study was performed without the scaffolding of a formal behaviour change model. In the second study, we showcase how a behaviour psychology model, COM-B (Capability, Opportunity, and Motivation-Behaviour), can be operationalised as a means of digital intervention to support behaviour change. We have developed four digital interventions manifested through a digital platform. We have demonstrated that it is possible to change behaviour concerning indoor activities using the COM-B model. We have also observed a measurable change in indoor air quality. In addition, qualitative analysis has shown that the awareness level among occupants has improved due to our approach of utilising IoT sensor data with COM-B-based digital interventions. [ABSTRACT FROM AUTHOR]

Formaldehyde evolves from various household items and is of environmental and public health concern. Removal of this contaminant from the indoor air is of utmost importance and currently, various practices are in the field. Among these practices, indoor plants are of particular importance because they help in controlling indoor temperature, moisture, and oxygen concentration. Plants and plant materials studied for the purpose have been reviewed hereunder. The main topics of the review are, mechanism of phytoremediation, plants and their benefits, plant material in formaldehyde remediation, and airtight environmental and health issues. Future research in the field is also highlighted which will help new researches to plan for the remediation of formaldehyde in indoor air. The remediation capacity of several plants has been tabulated and compared, which gives easy access to assess various plants for remediation of the target pollutant. Challenges and issues in the phytoremediation of formaldehyde are also discussed. Novelty statement: Phytoremediation is a well-known technique to mitigate various organic and inorganic pollutants. The technique has been used by various researchers for maintaining indoor air quality but its efficiency under real-world conditions and human activities is still a question and is vastly affected relative to laboratory conditions. Several modifications in the field are in progress, here in this review article we have summarized and highlighted new directions in the field which could be a better solution to the problem in the future. [ABSTRACT FROM AUTHOR]

Indoor formaldehyde pollution causes a serious threat to human health since it is uninterruptedly released from wooden furniture. Herein, we prepared a g-C3N4-modified TiO2 composite photocatalyst and coated it on the surface of a commercial artificial particle board with the assistance of melamine formaldehyde adhesive. The g-C3N4/ TiO2 coating was then used to degrade formaldehyde which was released in real-time from the particle board under the irradiation of visible light. The results showed that compared with pure TiO2, the g-C3N4/ TiO2 composite with a heterojunction structure had a lower band gap energy (~2.6 eV), which could effectively capture luminous energy from the visible light region. Under continuous irradiation, the g-C3N4/ TiO2 photocatalytic coating was capable of degrading more than 50% of formaldehyde constantly released from the particle board. In the meantime, the photocatalytic coating also exhibited promising catalytic stability towards various formaldehyde release speeds, air flow velocities and environmental humidities. The hydroxyl radical and superoxide radical were found to be the predominant active species which triggered formaldehyde degradation. This study provides a feasible and practical approach for the improvement in indoor air quality through photocatalyst surface engineering. [ABSTRACT FROM AUTHOR]

Demand management is expected to reduce emissions from energy systems and support the utilization of renewable energy sources. In this paper, the focus is on the viability of educational buildings' mechanical ventilation systems' participation in electric demand management. The results suggest that when load shedding lasts for a short duration, the ventilation machine load seems more promising than expected for electric demand management, as even 60% of its electric power could be granted to such markets. Prolonging the load-shedding duration increases the risk of the indoor carbon dioxide (CO2) concentration exceeding the limit for good indoor air quality. This paper contributes to the academic community by providing information for the assessment of the demand management potential of buildings and eventually their significance in decarbonizing the electric energy system and filling research gaps concerning the impact of implementing demand management that involves a reduction in ventilation rate. [ABSTRACT FROM AUTHOR]

BACKGROUND Air pollution is both a sensory blight and a threat to human health. Inhaled environmental pollutants can be naturally occurring or human-made, and include traffic-related air pollution (TRAP), ozone, particulate matter (PM) and volatile organic compounds, among other substances, including those from secondhand smoking. Studies of air pollution on reproductive and endocrine systems have reported associations of TRAP, secondhand smoke (SHS), organic solvents and biomass fueled-cooking with adverse birth outcomes. While some evidence suggests that air pollution contributes to infertility, the extant literature is mixed, and varying effects of pollutants have been reported. OBJECTIVE AND RATIONALE Although some reviews have studied the association between common outdoor air pollutants and time to pregnancy (TTP), there are no comprehensive reviews that also include exposure to indoor inhaled pollutants, such as airborne occupational toxicants and SHS. The current systematic review summarizes the strength of evidence for associations of outdoor air pollution, SHS and indoor inhaled air pollution with couple fecundability and identifies gaps and limitations in the literature to inform policy decisions and future research. SEARCH METHODS We performed an electronic search of six databases for original research articles in English published since 1990 on TTP or fecundability and a number of chemicals in the context of air pollution, inhalation and aerosolization. Standardized forms for screening, data extraction and study quality were developed using DistillerSR software and completed in duplicate. We used the Newcastle-Ottawa Scale to assess risk of bias and devised additional quality metrics based on specific methodological features of both air pollution and fecundability studies. OUTCOMES The search returned 5200 articles, 4994 of which were excluded at the level of title and abstract screening. After full-text screening, 35 papers remained for data extraction and synthesis. An additional 3 papers were identified independently that fit criteria, and 5 papers involving multiple routes of exposure were removed, yielding 33 articles from 28 studies for analysis. There were 8 papers that examined outdoor air quality, while 6 papers examined SHS exposure and 19 papers examined indoor air quality. The results indicated an association between outdoor air pollution and reduced fecundability, including TRAP and specifically nitrogen oxides and PM with a diameter of ≤2.5 µm, as well as exposure to SHS and formaldehyde. However, exposure windows differed greatly between studies as did the method of exposure assessment. There was little evidence that exposure to volatile solvents is associated with reduced fecundability. WIDER IMPLICATIONS The evidence suggests that exposure to outdoor air pollutants, SHS and some occupational inhaled pollutants may reduce fecundability. Future studies of SHS should use indoor air monitors and biomarkers to improve exposure assessment. Air monitors that capture real-time exposure can provide valuable insight about the role of indoor air pollution and are helpful in assessing the short-term acute effects of pollutants on TTP. [ABSTRACT FROM AUTHOR]

Formaldehyde is an important downstream chemical of syngas. Furniture and household products synthesized from formaldehyde will slowly decompose and release formaldehyde again during use, which seriously affects indoor air quality. In order to solve the indoor formaldehyde pollution problem, this paper took the catalytic oxidation of formaldehyde as the research object; prepared a series of low-cost, acid-treated manganese dioxide nanorod catalysts; and investigated the effect of the acid-treatment conditions on the catalysts' activity. It was found that the MnNR-0.3ac-6h catalyst with 0.3 mol/L sulfuric acid for 6 h had the best activity. The conversion rate of formaldehyde reached 98% at 150 °C and 90% at 25 °C at room temperature. During the reaction time of 144 h, the conversion rate of formaldehyde was about 90%, and the catalyst maintained a high activity. It was found that acid treatment could increase the number of oxygen vacancies on the surface of the catalysts and promote the production of reactive oxygen species. The amount of surface reactive oxygen species of the MnNR-0.3ac-6h catalyst was about 13% higher than that of the catalyst without acid treatment. [ABSTRACT FROM AUTHOR]

People spend most of their time indoors, and prolonged exposure to pollution can harm their health. The degradation of indoor air quality (IAQ) has raised serious issues. Botanical biofilters are an exciting solution for lowering indoor air pollution. However, plants cultivated inside under low light intensity (10–50 μmole PAR m−2 s−1) generate CO2 in the indoor atmosphere. Combining C3 (Calvin Cycle) and Crassulacean Acid metabolism (CAM) plants may be able to address this problem by lowering CO2 emission levels and enhancing the efficiency of pollution removal by removing the primary indoor air pollutants from actual interior settings, including carbon dioxide (CO2), formaldehyde (HCHO), particulate matter (PM2.5 and PM10), and total volatile organic compounds (TVOCs). As a result, a successful botanical biofilter made of several plants was researched. Indoor plants can phytoremediate a variety of indoor contaminants. However, just a few studies have demonstrated its efficacy in practical contexts. Due to the harsh winter, apartments in South Korea are frequently closed, necessitating the measurement of interior air pollution concentration in real-time. Four apartments (APT I through APT IV) with various ventilation and indoor plant setups were selected for this investigation. Various combinations of indoor environments (ventilation, low light) and a combination of C3 and CAM indoor plants as a botanical biofilter were used to study the sites over two months. Current research indicates that combining a botanical biofilter with ventilation can reduce levels of CO2, TVOCs, HCHO, PM2.5, and PM10 by 76%, 87%, 75%, 52%, and 51%, respectively. The current study concluded that different indoor potted plants provide an effective, affordable, self-regulating, sustainable option for enhancing indoor air quality and, consequently, human well-being and productivity in small, cramped places. [ABSTRACT FROM AUTHOR]

With the development of nanotechnology, an increasing number of nano‐enabled consumer products are introduced into the market. The release, deposition, and resuspension of particles from such products could be an important contributor to indoor air pollution and adverse health effects. Our study tested the spray and resuspension of seven nano‐enabled consumer products and investigated how flooring material and resuspension force affected the resuspension of particles from these products. Results show that resuspension rates can range from 10−4 to 5 × 10−1 h−1, depending on the product, flooring material (e.g., carpet and vinyl), and resuspension force (e.g., a walking adult and a moving child; the latter was simulated by a robotic sampler). The resuspension rate from the carpet was statistically significantly higher than that from vinyl flooring, while the resuspension rate by the adult was statiscally significantly higher than that by the robot. In addition, the interaction of investigated factors also played a role in particle resuspension rate. For a subgroup of products based on copper (Cu), silver (Ag), and zinc (Zn) nanomaterials, the resuspension rate reached as high 5 × 10−1 h−1, rates higher than those reported in existing studies with house dust or Arizona Road Dust. [ABSTRACT FROM AUTHOR]

Postpartum depression (PPD) is possibly caused by indoor air pollution and may be modified by maternal diet during pregnancy. Using the data from a prospective cohort study, we examined the interaction between indoor air quality and maternal dietary patterns on PPD development. A perceived indoor air quality (PIAQ) score was used to assess indoor air pollution. A higher PIAQ score indicated a worse indoor air quality. Women with higher PIAQ scores were at increased risk for PPD (tertile 3 vs. tertile 1, odds ratio [OR] = 2.12, 95% confidence interval [CI] = 1.37–3.29). Compared with a lower adherence to a "sweet foods pattern" (OR = 1.20, 95% CI = 0.66–2.18), a higher adherence to a "sweet foods pattern" enhanced the hazardous associations of the PIAQ on PPD (OR = 3.09, 95% CI = 1.81–5.27, adjusted p for interaction = 0.044). Higher adherence to a "whole grain‐seafood pattern" and lower adherence to a "traditional pattern" also increased the risk for PPD, although the p values for the interaction were not significant. Our findings provide further evidence of the link between diet during pregnancy, air pollution, and PPD, and it can be used to develop PPD prevention strategies. [ABSTRACT FROM AUTHOR]

Much of the global population spends most of their time indoors; however, air pollution measurement, a proxy of exposure, occurs primarily outdoors. This fundamental disconnect between where the people are and where the measurements are made likely leads to misestimation of the true burden of air pollution on human health, which is already substantial, with exposure leading to approximately 6.7 million deaths yearly. In this review, we describe the two disparate but linked fields commonly referred to as indoor air pollution and household air pollution. Both fields focus on the measurement and characterization of exposures and subsequent health effects that occur primarily in the indoor environment. The former tends to focus on issues in the developed world, whereas the latter focuses on issues in low- and middle-income countries reliant on solid fuels, like wood, dung, coal, and crop residues, for basic household energy needs. Both lead to substantial exposures to air pollutants that are damaging to human health. We describe and contrast both contexts and provide potential topics for conversation between the disciplines. [ABSTRACT FROM AUTHOR]

The Healthy Air, Healthy Schools Study was established to better understand the impact of ultrafine particles (UFPs) on indoor air quality in communities surrounding Seattle-Tacoma (Sea-Tac) International Airport. The study team took multipollutant measurements of indoor and outdoor air pollution at five participating school locations to estimate infiltration indoors. The schools participating in this project were located within a 7-mile radius of Sea-Tac International Airport and within 0.5 mile of an active flight path. Based on experimental measures in an unoccupied classroom, infiltration rates of (a) UFPs of aircraft origin, (b) UFPs of traffic origin, and (c) wildfire smoke or other outdoor pollutants were characterized before and after the introduction of a portable high-efficiency particulate air (HEPA) filter intervention. The portable HEPA cleaners were an effective short-term intervention to improve the air quality in classroom environments, reducing the UFP count concentration from one-half to approximately one-tenth of that measured outside. This study is unique in focusing on UFPs in schools and demonstrating that UFPs measured in classroom spaces are primarily of outdoor origin. Although existing research suggests that reducing particulate matter in homes can significantly improve asthma outcomes, further investigation is necessary to establish the benefits to student health and academic performance of reducing UFP exposures in schools. [ABSTRACT FROM AUTHOR]

Indoor air quality (IAQ) in houses is often deteriorated by chemical substances emitted from heating, building materials, or other household goods. Since it is difficult for occupants to recognize air pollution, they rarely understand the actual conditions of the IAQ. An investigation into the actual condition of IAQ in houses was therefore conducted in this study. Carbon dioxide ( CO 2 ) concentrations in 24 occupied houses was measured, and the results from our analysis showed that the use of combustion heaters increased the concentration of CO 2 and led to indoor air pollution. Results indicate that as outdoor temperature decreased, the frequency of ventilation decreased simultaneously, and CO 2 concentration increased. Results of the questionnaire survey revealed that the actual IAQ in each house did not match the level of awareness its occupants had regarding ventilation. Along with this difficulty in perceiving air pollution, the lack of knowledge about ventilation systems and the effects of combustion heating may be additional barriers to IAQ awareness. [ABSTRACT FROM AUTHOR]

Environmental tobacco smoke (ETS) has become one of the most important sources of indoor air pollution. The study aimed to obtain the variation characteristics of typical air pollutant concentrations when people smoke in a closed room and explore the effect of the air-conditioner. A closed and air-conditioned room of 21 m2 was taken as the research object. Fine particulate matter (PM2.5) and total volatile organic compound (TVOC) were measured while 10 cigarettes were burnt in smoldering or smoking mode, with the air-conditioner on or off. The contents of nicotine in condensate samples were obtained by liquid chromatography. The impact of ETS on indoor air quality lasted for hours, causing typical pollutant concentrations to far exceed the Chinese standard. The PM2.5 produced by smoking was 11 times higher than by smoldering, but the TVOC produced by smoldering was more than by smoking. After one hour of the cigarette burning off, the PM2.5 concentration would be decreased by 96.1% with the air-conditioner on, in contrast to 67.9% with the air-conditioner off. Nicotine was detected in all samples of condensate from the air-conditioner. It is concluded that smoking cigarettes cannot be replaced by smoldering to evaluate the pollution of ETS. The air-conditioner has a positive effect on reducing the concentration of air pollutants produced by cigarette burning. More than 10% of the indoor nicotine may be taken away by condensate discharge, and its possible pollution should be paid attention to. Implications: This study provides new evidence of the effect of the split-type air-conditioner on ETS. The TVOC concentrations, which were less considered previously, were measured. PM2.5 concentration in human breathing zone can be reduced more quickly with the air-conditioner on. This study shows that there is a big difference in the concentrations of typical pollutants between smoking and smoldering. And it could be a guide for the formulation of relevant research methods. This study also demonstrates that the air conditioning condensate from the smoking room may contain nicotine. Attention should be paid to the recovery and utilization of such condensate. [ABSTRACT FROM AUTHOR]

Indoor air pollution is complex and serious. In fact, an on-site investigation of an office building revealed that the concentration of three typical pollutants (CO2, VOCs, PM2.5) exceeded the Chinese standard. To identify a better control method to achieve good indoor air quality, an orthogonal experiment was carried out in an environmental chamber to compare the control time and energy consumption of four control methods (purifier+ and window+, purifier+ and window-, purified fresh air 240 m3/h and purified fresh air 400 m3/h) to meet the standard established for pollutants. The purifier+ and window+ method was found to be more effective in most conditions, with a control time reduced by 8.06% and energy consumption reduced by 11.91% compared with the traditional control method of purified fresh air 240 m3/h. This research highlights the optimal control strategy for the air quality in office buildings under different pollution conditions. [ABSTRACT FROM AUTHOR]

Air pollution is a severe problem for the global environment. Most people spend 80% to 90% of the day indoors; therefore, indoor air pollution is as important as outdoor air pollution. The problem is more severe on school campuses. There are several ways to improve indoor air quality, such as air cleaners or ventilation. Air-quality sensors can be used to detect indoor air quality in real time to turn on air cleaner or ventilation. With an efficient and accurate clustering technique for indoor air-quality data, different ventilation strategies can be applied to achieve a better ventilation policy with accurate prediction results to improve indoor air quality. This study aims to cluster the indoor air quality data (i.e., CO2 level) collected from the school campus in Taiwan without other external information, such as geographical location or field usage. In this paper, we propose the Max Fast Fourier Transform (maxFFT) Clustering Approach to classify indoor air quality to improve the efficiency of the clustering and extract the required feature. The results show that without using geographical information or field usage, the clustering results can correctly reflect the ventilation condition of the space with low computation time. [ABSTRACT FROM AUTHOR]

The last two decades have witnessed rapid urbanization and economic growth accompanied by severe indoor air pollution of volatile organic compounds (VOCs) in China. However, indoor VOC pollution across China has not been well characterized and documented. This study is a systematic review of field measurements of eight target VOCs (benzene, toluene, xylenes, acetaldehyde, p‐dichlorobenzene, butadiene, trichloroethylene, and tetrachloroethylene) in residences, offices, and schools in China from 2000 to 2021. The results show that indoor pollution of benzene, toluene, and xylenes has been more serious in China than in other countries. Spatiotemporal distribution shows lower indoor VOC levels in east and south‐east regions and a declining trend from 2000 to 2021. Moving into a dwelling more than 1 year after decoration and improving ventilation could significantly reduce exposure to indoor VOCs. Reducing benzene exposure is urgently needed because it is associated with greater health risks (4.5 × 10−4 for lifetime cancer risk and 8.3 for hazard quotient) than any other VOCs. The present study enriches the database of indoor VOC levels and provides scientific evidence for improving national indoor air quality standards as well as estimating the attributable disease burden caused by VOCs in China. [ABSTRACT FROM AUTHOR]

Introduction: Almost 3 billion of the world's poorest people still rely on solid fuels, with a concomitant increase in indoor Particulate Matter (PM 2.5) concentration resulting in deaths from respiratory diseases. Increased prevalence of respiratory diseases among never smoking young individuals and fairly among women compared to men point towards a causal relationship between chronic smoke inhalation resulting from the burning of biomass fuels. Aim: To assess the quantitative exposure levels of PM 2.5 in a rural setting in South India and determine the association between PM 2.5, type of house, ventilation available and fuel used. Materials and Methods: This community-based cross-sectional study was conducted for 3 months from September 2020 to November 2020 in the rural field practice area of Sri Ramachandra Institute of Higher Education and Research, Chennai, Tamil Nadu. The houses were classified into three types Kutcha (roof, walls, and floor made of poor-quality materials), semi pucca (two components made of good quality material and one component is of poor quality), and pucca (roof, walls, and floor made of good quality material) houses according to Census of India 1991. The air quality inside 127 houses was assessed by measuring PM2.5 levels for 24 hours in both kitchen and living rooms. The association between house characteristics, ventilation, type of fuel, and indoor air quality was Studied using student t-test and one-way Analysis Of Variance (ANOVA). Results: Among 323 included residents, 168 were males and 155 females with the mean age 36.99±13.24 years. The difference in average house area and living area between the three types of houses were statistically significant (p-value<0.001). The mean concentrations of PM2.5 were 290.07 µg/m3 and mean differences in PM2.5 levels in living room and kitchen of semi pucca (t=7.32, p-value<0.001) and pucca houses (t=5.47, p-value<0.001) were significant. The association between cross ventilation in kitchen (OR 3.24, p-value=0.042), artificial ventilation (OR 3.23, p=0.026), type of fuel (firewood OR 2.85, p-value=0.042) and PM2.5 levels is significant at 95% CI limits. Conclusion: Indoor air pollution is a silent killer responsible for several respiratory problems. Simple cost-effective measures could reduce indoor PM2.5 levels and thereby indoor air pollution. [ABSTRACT FROM AUTHOR]

Public school teachers represent one of the largest occupational groups in the United States and are vulnerable to job stress and burnout. School social and physical environments may be adversely impacting the health of teachers and other staff, though few studies have explored these relationships. We partnered with a suburban school district in Colorado to assess the association between school environmental quality, social climate, and staff member health. We modeled the number of self-reported frequent health symptoms (experienced at least once a week) using generalized linear models. School-level predictors of interest included: overall social climate scores (unitless), building operations report card (ORC) scores (unitless), and indoor air quality (IAQ) scores (unitless). In total, we had data from 134 staff members from 11 schools in the district. A majority (62%) of our participants were teachers, who reported a greater number of frequent (i.e., at least once a week) health symptoms (mean = 3.2 symptoms experienced at least once per week) compared to staff in other roles (mean = 2.3 symptoms per week). We found that a one standard-deviation (10.5) increase in the overall social climate score was associated with a 0.77-fold (95% CI: 0.60–0.99) change in the number of frequent health symptoms reported. However, this association was attenuated among teachers compared to other staff members. Our results suggested effect modification by social climate on the relationship between IAQ and health, albeit with some uncertainty. For participants with a school climate score below the mean, a one standard-deviation (10.5) increase in IAQ score was associated with a 0.49-fold (95% CI: 0.35–0.70) change in the number of frequently reported symptoms. Overall, our study suggests school climate may be associated with self-reported health symptoms, but that the benefits of improved school climates may not be as strong for teachers compared to other staff. Future work should assess perceived climate at the individual level to assess how staff roles impact how school environments are associated with health outcomes. [ABSTRACT FROM AUTHOR]

The coronavirus (COVID‐19) lockdown in China is thought to have reduced air pollution emissions due to reduced human mobility and economic activities. Few studies have assessed the impacts of COVID‐19 on community and indoor air quality in environments with diverse socioeconomic and household energy use patterns. The main goal of this study was to evaluate whether indoor and community air pollution differed before, during, and after the COVID‐19 lockdown in homes with different energy use patterns. Using calibrated real‐time PM2.5 sensors, we measured indoor and community air quality in 147 homes from 30 villages in Beijing over 4 months including periods before, during, and after the COVID‐19 lockdown. Community pollution was higher during the lockdown (61 ± 47 μg/m3) compared with before (45 ± 35 μg/m3, p < 0.001) and after (47 ± 37 μg/m3, p < 0.001) the lockdown. However, we did not observe significantly increased indoor PM2.5 during the COVID‐19 lockdown. Indoor‐generated PM2.5 in homes using clean energy for heating without smokers was the lowest compared with those using solid fuel with/without smokers, implying air pollutant emissions are reduced in homes using clean energy. Indoor air quality may not have been impacted by the COVID‐19 lockdown in rural settings in China and appeared to be more impacted by the household energy choice and indoor smoking than the COVID‐19 lockdown. As clean energy transitions occurred in rural households in northern China, our work highlights the importance of understanding multiple possible indoor sources to interpret the impacts of interventions, intended or otherwise. [ABSTRACT FROM AUTHOR]

Unhealthy levels of fine particulate matter (PM2.5) from the local burning of solid fuels, and from regional transport of pollutants, remain a major public health problem in the Himalayan foothill villages in Nepal. Teahouses (i.e., mountain lodges) along popular hiking trails in the lower Himalayas commonly use wood as the primary energy source for heating; however, little is known about teahouse air quality. The purpose of this study was to characterize the levels and chemical constituents of indoor and ambient PM2.5 at three villages along the Poon Hill circuit trek in the Annapurna Conservation Area in Nepal. A convenience sample of five PM2.5 measurements was collected with portable MicroPEM V.3.2A exposure monitors. Filters were analyzed for black and brown carbon using integrating sphere optical transmittance and 33 elemental constituents using energy-dispersive X-ray fluorescence. Median indoor PM2.5 over the sampling period was 41.3 µg/m3, whereas median ambient PM2.5 over the sampling period was 34.7 µg/m3. Chemical species associated with wood smoke, such as potassium (GM = 0.88 µg/m3), predominated. High indoor and ambient PM2.5 levels may pose a significant occupational health risk to teahouse workers, who may experience chronic exposures during trekking seasons. Our findings warrant additional research to characterize teahouse air pollution exposures more fully and to evaluate intervention measures. [ABSTRACT FROM AUTHOR]

We surveyed literature on measurements of indoor particulate matter in all size fractions, in residential environments free of solid fuel combustion (other than wood for recreation or space heating). Data from worldwide studies from 1990 to 2019 were assembled into the most comprehensive collection to date. Out of 2752 publications retrieved, 538 articles from 433 research projects met inclusion criteria and reported unique data, from which more than 2000 unique sets of indoor PM measurements were collected. Distributions of mean concentrations were compiled, weighted by study size. Long‐term trends, the impact of non‐smoking, air cleaners, and the influence of outdoor PM were also evaluated. Similar patterns of indoor PM distributions for North America and Europe could reflect similarities in the indoor environments of these regions. Greater observed variability for all regions of Asia may reflect greater heterogeneity in indoor conditions, but also low numbers of studies for some regions. Indoor PM concentrations of all size fractions were mostly stable over the survey period, with the exception of observed declines in PM2.5 in European and North American studies, and in PM10 in North America. While outdoor concentrations were correlated with indoor concentrations across studies, indoor concentrations had higher variability, illustrating a limitation of using outdoor measurements to approximate indoor PM exposures. [ABSTRACT FROM AUTHOR]

Effective evidence-based actions to reduce indoor air pollution must be derived from data obtained using accurate means for assessment of the critical air pollutants and for the identification of their sources. This is of paramount importance to provide robust evidence for establishing effective policies or preventive measures. Nevertheless, designing a reliable sampling plan for assessing concentration of inorganic pollutant in the indoor air requires expertise in conducting rigorous sampling campaigns and proper knowledge on the existing standards and methodologies for assessing concentration of the target substances. Therefore, this review focuses on the relevant information and recommendations that should be considered when designing a sampling plan to collect complementary data on the indoor environment under study, to properly define the criteria for establishing the details for the work and to ensure the quality of the assessments. In particular, comprehensive information on the most commonly used methodologies for the determination of a list of critical inorganic pollutants for indoor air quality monitoring has been compiled. Thus, inorganic gaseous pollutants such as CO2, CO, O3, NO2, NO, NH3, SO2, H2O2, H2S, HNO3 and HNCO are included in the present review. [ABSTRACT FROM AUTHOR]

This systematic review and meta-analysis investigated studies on formaldehyde (FA) inhalation exposure in indoor environments and related carcinogenic (CR) and non-carcinogenic (HQ) risk. Studies were obtained from Scopus, PubMed, Web of Science, Medline, and Embase databases without time limitation until November 21, 2023. Studies not meeting the criteria of Population, Exposure, Comparator, and Outcomes (PECO) were excluded. The 45 articles included belonged to the 5 types of sites: dwelling environments, educational centers, kindergartens, vehicle cabins, and other indoor environments. A meta-analysis determined the average effect size (ES) between indoor FA concentrations, CR, and HQ values in each type of indoor environment. FA concentrations ranged from 0.01 to 1620 μg/m3. The highest FA concentrations were stated in water pipe cafés and the lowest in residential environments. In more than 90% of the studies uncertain (1.00 ×10−6 1.00 ×10−4) due to FA inhalation exposure was reported and non-carcinogenic risk was stated acceptable. The meta-analysis revealed the highest CR values due to inhalation of indoor FA in high-income countries. As 90% of the time is spent indoors, it is crucial to adopt effective strategies to reduce FA concentrations, especially in kindergartens and schools, with regular monitoring of indoor air quality. [Display omitted] • Formaldehyde (FA) is one of the most abundant pollutants in indoor air. • FA concentrations in various indoor environments ranged from 0.01 to 1620 μg/m3. • Formaldehyde levels were higher in kindergartens than in other educational centers. • In over 90% of the studies, the risk of carcinogenesis was higher than 1.00 × 10−6. [ABSTRACT FROM AUTHOR]

Porous fabrics have a significant impact on indoor air quality by adsorbing and emitting chemical substances, such as volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs). Understanding the partition behavior between organic compound molecules and indoor fabrics is crucial for assessing their environmental fate and associated human exposure. The physicochemical properties of fabrics and compounds are fundamental in determining the free energy of partitioning. Moreover, environmental factors like temperature and humidity critically affect the partition process by modifying the thermal and moisture conditions of the fabric. However, existing methods for determining the fabric-air partition coefficient are limited to specific fabric-chemical combinations and lack a comprehensive consideration of indoor environmental factors. In this study, large amounts of experimental data on fabric-air partition coefficients (K fa) of (S)VOCs were collected for silk, polyester, and cotton fabrics. Key molecular descriptors were identified, integrating the influences of physicochemical properties, temperature, and humidity. Subsequently, two typical quantitative structure-property relationship (QSPR) models were developed to correlate the K fa values with the molecular descriptors. The fitting performance, robustness, and predictive ability of the two QSPR models were evaluated through statistical analysis and internal/external validation. This research provides insights for the high-throughput prediction of the environmental behaviors of indoor organic compounds. Among various indoor surfaces, porous fabrics serve as the primary medium for the migration, distribution, and fate of chemicals, owing to their high loading rate and large specific surface area. Understanding the partition behavior of organic compounds between fabric and air is essential. However, existing methods are often restricted to specific fabric-chemical combinations and lack a comprehensive consideration of indoor environmental factors. This study introduces a QSPR modeling approach with broad applicability, effectively predicting the fabric-air partition coefficients of (S)VOCs, and incorporating the effects of ambient temperature and humidity. It enables high-throughput assessment of indoor chemical pollution and human exposure. [Display omitted] • QSPR modeling was used to predict fabric-air partition coefficients for (S)VOCs. • Key molecular and environmental descriptors were identified and integrated. • Two advanced and well validated models were proposed for different scenarios. • Study facilitates high-throughput assessment of chemical fate and human exposure. [ABSTRACT FROM AUTHOR]

Environmental exposures, such as ambient air pollution and household fuel use affect health and under-5 mortality (U5M) but there is a paucity of data in the Global South. This study examined early-life exposure to ambient particulate matter with a diameter of 2.5 µm or less (PM 2.5), alongside household characteristics (including self-reported household fuel use), and their relationship with U5M in the Navrongo Health and Demographic Surveillance Site (HDSS) in northern Ghana. We employed Satellite-based spatiotemporal models to estimate the annual average PM 2.5 concentrations with the Navrongo HDSS area (1998 to 2016). Early-life exposure levels were determined by pollution estimates at birth year. Socio-demographic and household data, including cooking fuel, were gathered during routine surveillance. Cox proportional hazards models were applied to assess the link between early-life PM2.5 exposure and U5M, accounting for child, maternal, and household factors. We retrospectively studied 48,352 children born between 2007 and 2017, with 1872 recorded deaths, primarily due to malaria, sepsis, and acute respiratory infection. Mean early-life PM 2.5 was 39.3 µg/m3, and no significant association with U5M was observed. However, Children from households using "unclean" cooking fuels (wood, charcoal, dung, and agricultural waste) faced a 73 % higher risk of death compared to those using clean fuels (adjusted HR = 1.73; 95 % CI: 1.29, 2.33). Being born female or to mothers aged 20–34 years were linked to increased survival probabilities. The use of "unclean" cooking fuel in the Navrongo HDSS was associated with under-5 mortality, highlighting the need to improve indoor air quality by introducing cleaner fuels. [ABSTRACT FROM AUTHOR]

Introduction: Respirable Suspended Particulate (RSP) is a particularly serious indoor air pollution since at least a portion of particles ingested by humans can be permanently deposited in the respiratory tract. Analysis of indoor air quality in school classrooms is essential because the air quality can have a significant impact on the health and performance of children. Methods: The site selections were based on the surrounding activities of commercial and industrial areas. Instruments used for measuring parameters are Dust TraxTM DRX Aerosol II 8532 and Kanomax IAQ Monitor. Results: The study shows that the commercial area has a higher concentration of RSP compared to the industrial area. The I/O ratio value is higher at commercial area compared to industrial area with the value of PM10 = 3.065, PM2.5 = 3.222, PM1 = 3.261, CO2 =1.242, RH = 1.212, temperature = 0.891, and air movement = 1.072 for commercial area, and PM10 = 1.482, PM2.5 = 1.456, PM1 = 1.449, CO2 =1.116, RH = 1.134, temperature = 1.040, and air movement = 1.008 for the industrial area. For a commercial area, the indoor RSP is strongly correlated to all meteorological parameters with the value exceeding 0.5 except for CO2 has moderately correlated with the value is between 0.4 to 0.49, and wind speed has weak correlate with the value is less than 0.39. Conclusion: In conclusion, the classroom located in commercial is more polluted compared to the industrial area and the RSP is significantly influenced by meteorological factors. [ABSTRACT FROM AUTHOR]