Indoor air最新文献

{"title":"Exploring the Interconnection of Sleep Quality, Indoor Environmental Factors, and Energy Efficiency: Strategies for Sustainable Sleep Environments","authors":"Sadia Yasmeen,&nbsp;Baizhan Li,&nbsp;Chenqiu Du,&nbsp;Hong Liu","doi":"10.1155/ina/8245786","DOIUrl":"https://doi.org/10.1155/ina/8245786","url":null,"abstract":"<p>This narrative review synthesizes interdisciplinary evidence on how indoor environmental factors, thermal conditions, lighting, noise, and air quality affect sleep quality and evaluates interventions to optimize these factors in energy-efficient buildings. We analyzed peer-reviewed studies (2000–2024) from Web of Science, ScienceDirect, PubMed, Scopus, and Wiley, selected through a structured screening process focusing on human studies in nonclinical settings. Evidence synthesis suggests that (1) moderate thermal environments, generally ranging between 18°C and 22°C, support sleep continuity in most healthy adults, though optimal thresholds may vary by age, region, and season. (2) Evening exposure to short-wavelength blue light, typically above 30–50 lux at 460–480 nm, disrupts circadian timing, particularly in adolescents and sensitive populations. (3) Nighttime noise levels above ~35 dB (A) are linked to rapid eye movement (REM) sleep disruption, with sensitivity varying by individual and noise source. (4) PM_2.5 and CO₂ accumulation in poorly ventilated bedrooms contribute to increased sleep fragmentation. Strategies like broadened HVAC setpoints and nighttime ventilation offer energy-saving potential without compromising sleep quality, but empirical support is sparse. Promising interventions, including dynamic lighting, acoustic insulation, and intelligent ventilation, need further validation in real-world settings. This review highlights the need for sleep-centric building standards and policies that prioritize both occupant health and energy efficiency. Future research should focus on personalized interventions and longitudinal studies to address mechanistic gaps.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/8245786","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145224210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synergizing Health and Technology in Green Buildings: A Critical Review of Indoor Air Quality Monitoring and Solutions","authors":"Muhammad Tariq Bashir,&nbsp;Raid Alrowais,&nbsp;Ratan Lal,&nbsp;Manahil Bashir,&nbsp;Muhammad Ali Sikandar,&nbsp;Nabeeha Zahid,&nbsp;Md. Munir Hayet Khan,&nbsp;Syed Saad,&nbsp;Muhammad Inam Abbas,&nbsp;M. Waqas Khan,&nbsp;Zawar Ali","doi":"10.1155/ina/1281155","DOIUrl":"https://doi.org/10.1155/ina/1281155","url":null,"abstract":"<p>This comprehensive critical review shows how green buildings and energy optimization solutions improve indoor air quality (IAQ) as well as indoor environmental quality (IEQ) and human health. The growing emphasis on sustainable living has led to the establishment of green and sustainable building approaches, which are widely acknowledged for their energy efficiency and potential to reduce costs. A systematic analysis of 128 peer-reviewed publications was conducted, including studies on design and materials, IAQ monitoring technologies, and health impacts. Technologies such as low-cost sensors including Dylos, Foobot, and AirVisual Pro, as well as communication systems like Wi-Fi, LoRa, Bluetooth, and VLC, are assessed based on their performance, limitations, and practical use in real-time IAQ monitoring. Key challenges include sensor drift, maintenance demands, environmental sensitivity, and regulatory barriers in specific regions. Intelligent calibration models and integration strategies are explored to enhance data accuracy and system longevity. While green buildings generally offer better IAQ, effectiveness varies due to outdoor pollution, building age, and material selection. The study emphasizes the need for a holistic, health-driven approach in sustainable building design that combines architecture, technology, and human well-being to foster resilient and healthier indoor environments.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/1281155","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145224211","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Air Pollution Control: Comparative Analysis of VOC Regulations Across Mainland China, the EU, and the US","authors":"C. K. Law,&nbsp;Savannah Y. T. Lai,&nbsp;Joseph H. K. Lai","doi":"10.1155/ina/6743635","DOIUrl":"https://doi.org/10.1155/ina/6743635","url":null,"abstract":"<p>Air pollution, especially the rising ground-level ozone (O₃) levels, poses a critical global challenge to public health and environmental sustainability. Volatile organic compounds (VOCs), which are key precursors to O₃ formation, are primarily emitted from various household chemical products. Given the lack of a thorough understanding of the current regulatory control on VOC emissions and the need to identify ways to curb these emissions, a comparative analysis was conducted on the VOC regulations across three major economies: Mainland China, the European Union (EU), and the United States. The analysis reveals distinct regulatory frameworks and approaches: (i) the United States exemplifies a robust control framework characterized by detailed product categorization, stringent VOC limits, and many control parameters; (ii) the EU adopts a relatively streamlined approach, primarily targeting certain types of architectural paints and relying on ecolabel for specific cleaning products; and (iii) Mainland China employs a broad regulatory approach, permitting a range of solvent-borne products with comparatively lenient VOC limits, while tightening penalty mechanisms and broadening the scope of regulated entities. Comparatively, the EU and Mainland China place less emphasis on governing consumer products such as air fresheners, while the United States and Mainland China implement the polluter-pays principle, including VOC taxes. In addition to forging international collaboration to enhance cross-border regulatory control of VOCs, future work is needed to explore establishing stricter emission standards, implementing comprehensive bans on specific high-VOC products, and providing financial incentives and technological upgrades for the transition to low-VOC alternatives.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/6743635","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145146702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Simulation of Contaminant Transport and Infection Probability in Public Transport Vehicles","authors":"Jordi Vera,&nbsp;Eugenio Schillaci,&nbsp;Ahmad Amani,&nbsp;Nina Morozova,&nbsp;Joaquim Rigola","doi":"10.1155/ina/5662076","DOIUrl":"https://doi.org/10.1155/ina/5662076","url":null,"abstract":"<p>In this work, a numerical set-up is built to perform transient numerical simulations of airflow quality, contaminant transport, and risk of infection within enclosed spaces. In particular, the case of an urban bus is proposed by studying the probability of infection from SARS CoV-2 during typical urban travel. Different air supply units are analyzed: an air-conditioning device with partial outside air recirculation and an air purification system with continuous indoor air purification and different air diffuser configurations. The infection probability is evaluated using an original methodology based on the Wells–Riley model. The generation and transport of airborne infections are considered by solving a quanta transport equation that uses empirical values for quanta exhalation and inhalation rates. The flow field is solved once using URANS models. Next, different target positions for infectious and target susceptible people are simulated to build a general infection probability matrix, allowing the quantification of the risk of contagion by running a set of affordable transient simulations. Air age and PM_2.5 concentration are also employed to evaluate general air quality. The numerical model, experimentally validated in past works, is verified here using a mesh convergence analysis. Hence, the different air supply units and configurations are analyzed with the current methodology to quantify the risk of infection, showing a 13% risk reduction when introducing the air purification unit and a 23% reduction when using the same unit but with a more efficient grid configuration.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/5662076","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145146746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perception of Thermal Comfort During Exercise","authors":"Martin Fletcher","doi":"10.1155/ina/5580860","DOIUrl":"https://doi.org/10.1155/ina/5580860","url":null,"abstract":"<p>Exercise is a significant contributor to health and wellbeing, and many activities rely on a dedicated indoor facility to take place. Substantial resource is used to condition indoor sport facilities despite there being limited understanding of what constitutes thermal comfort during exercise. Conventional metrics to evaluate thermal comfort are derived from sedentary or near-sedentary individuals, prompting investigation into the fundamental notions of comfort during exercise. Whilst insightful, prior research on this topic has predominantly occurred in laboratory settings that lack experiential realism. Thermal surveys to explore occupant sensation, comfort, preference, acceptability, tolerance and environmental perception were undertaken in a naturally ventilated multipurpose indoor sports hall in the United Kingdom over a 24-month period. Environmental conditions were monitored at four locations in the hall, with the sample encompassing low (&lt; 3 MET), medium (3–5 MET) and high (&gt; 5 MET) activity intensities. The study highlights the complexity of monitoring large open indoor spaces, particularly direct measurement of radiant effects at the centre of the space. Using nonparametric methods, data were analysed to evaluate thermal judgements and their implications for space conditioning. Comfort was observed across a broad range of environmental air temperatures (13°C–24°C), with discomfort increasing as thermal sensation became more intense. Exercising individuals exhibited a drift in thermal neutrality, with a preference for a warmer personal thermal sensation corresponding to +0.7 scale points on the thermal sensation scale. This did not apply to environmental air temperature, where preference was for thermally neutral conditions (i.e., neither cool nor warm). This suggests that the commonly used 7-point thermal sensation scale is not an appropriate proxy for satisfaction with environmental conditions for exercising individuals. Metabolic rate was significant in the perception of thermal sensation during exercise (<i>r</i>_<i>s</i> = 0.337, <i>p</i> &lt; 0.001), with environmental conditions observed to have less impact. Environmental air temperature was, however, a critical factor for the acceptance (<i>r</i>_<i>s</i> = −0.269, <i>p</i> = 0.002) and tolerance (<i>r</i>_<i>s</i> = 0.283, <i>p</i> = 0.001) of overall thermal state, declining where environmental conditions exceeded 24°C and highlighting the significance of appropriate sport facility conditioning strategies.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/5580860","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145111336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occurrence of Novel Alternative Phosphorus Flame Retardants on Indoor Dust Collected From Japanese Dwellings and a Kindergarten","authors":"Yuichi Miyake,&nbsp;Masahiro Tokumura,&nbsp;Qi Wang,&nbsp;Yukari Takahashi,&nbsp;Kazunari Kume,&nbsp;Takashi Amagai","doi":"10.1155/ina/9596823","DOIUrl":"https://doi.org/10.1155/ina/9596823","url":null,"abstract":"<p>Alternative flame retardants, especially those containing phosphorus, have changed over time to meet flammability standards; however, studies on the presence of these alternatives on indoor dust, which is a major exposure carrier to human beings, have been limited. In this study, we measured the concentrations of four novel phosphorus flame retardants (PFRs), including 6-benzylbenzo[<i>c</i>][2,1]benzoxaphosphinine 6-oxide (BzlDOPO), naphthalen-2-yl diphenyl phosphate (NDPhP), (5-ethyl-2-methyl-2-oxido-1,3,2-dioxaphosphorinan-5-yl)methyl methyl methylphosphonate (PMMMP), and bis[(5-ethyl-2-methyl-2-oxido-1,3,2-dioxaphosphinan-5-yl)methyl] methylphosphonate (di-PMMMP), and 13 conventional PFRs on indoor dust collected from 29 dwellings and a kindergarten in Japan. The concentration of the PFRs on indoor dust ranged from 3.0 ng g⁻¹ (TPP [tripropyl phosphate]) to 4,600,000 ng g⁻¹ (TBOEP [tris (2-butoxyethyl) phosphate]). Among the PFRs targeted in this study, TBOEP exhibited the highest median concentration, followed by tris(2-chloroisopropyl) phosphate (TCPP), tris(2-chloroethyl) phosphate (TCEP) and triphenyl phosphate (TPhP), and tris(1,3-dichloro-2-propyl) phosphate (TDCPP). The novel PFRs, PMMMP, di-PMMMP, BzlDOPO, and NDPhP, were detected at 51, 63, 6, and 3 ng g⁻¹, respectively, in dust samples. TBOEP exhibited the lowest margin of exposure (1.5 × 10³ [5%ile]) among the PFRs examined. The results indicate that the novel PFRs are present in indoor environments and that humans are exposed through indoor dust. Further studies are needed to evaluate the toxicity of novel PFRs and assess their potential health risks.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/9596823","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145101526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Occupant Perception and Indoor Environmental Quality in a University Dormitory: A Case Study From South Korea","authors":"Sang Hee Park,&nbsp;Kyoung Woo Kim,&nbsp;Ki Hyung Yu,&nbsp;Junsub Kim,&nbsp;Sun Ho Kim,&nbsp;Seung Min Lee","doi":"10.1155/ina/9946691","DOIUrl":"https://doi.org/10.1155/ina/9946691","url":null,"abstract":"<p>This study examined the relationship between measured indoor environmental factors and occupant perception in a university dormitory in South Korea. Temperature, relative humidity, and carbon dioxide (CO₂) levels were measured in individual rooms, while residents completed surveys assessing their perceptions of thermal environment, air quality, lighting, acoustic environment, and overall indoor environmental quality (IEQ). The analysis revealed distinct patterns across satisfaction groups: perceptions of thermal comfort and air quality were the strongest predictors of overall satisfaction among occupants with low IEQ ratings, while perceptions of natural daylight and acoustic conditions were more influential among highly satisfied occupants. For participants highly satisfied with thermal conditions, fluctuations in humidity significantly predicted satisfaction. Similarly, for those highly satisfied with air quality, variations in CO₂ concentration emerged as a key factor. Greater variability in environmental conditions, rather than static control, was associated with higher satisfaction levels, highlighting the potential benefits of dynamic environmental management strategies. These findings offer insights into the nuanced interplay between objective indoor conditions and subjective occupant perceptions, underscoring the importance of user-centered design and operation in residential buildings such as university dormitories.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/9946691","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145101877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Indoor Exposure to Volatile Organic Compounds (Benzene, Toluene, Xylene, and Formaldehyde) and Associated Health Risk in Hotels of Hunan, China","authors":"Min Zhang,&nbsp;Yue Li,&nbsp;Xinge Zhang,&nbsp;Ji Hu,&nbsp;Lingshuang Lv,&nbsp;Ning An,&nbsp;Zhiguang Liu,&nbsp;Jun Rao,&nbsp;Chunliang Zhou,&nbsp;Xiuying Liu","doi":"10.1155/ina/3747936","DOIUrl":"https://doi.org/10.1155/ina/3747936","url":null,"abstract":"<p><b>Background:</b> Indoor air pollution caused by volatile organic compounds (VOCs) has garnered considerable attention, but its extent in hotel environments remains underexplored. This research was aimed at measuring the levels of VOCs (benzene, toluene, xylene, and formaldehyde) in hotels and evaluate their health risks using quantitative risk assessment methods, including lifetime carcinogenic risk (R) and noncarcinogenic hazard quotient (HQ).</p><p><b>Method:</b> Air samples were gathered from 79 hotels during the summer and winter of 2023. We analyzed the concentrations of four VOCs and conducted a descriptive analysis of the results. Spearman’s rank correlation and principal component analysis were utilized for statistical evaluation. US EPA guidelines were used to calculate both carcinogenic and noncarcinogenic risks, with uncertainty quantified through Monte Carlo simulation (10,000 iterations) to derive probabilistic risk distributions.</p><p><b>Results:</b> Formaldehyde was the most abundant compound found in hotels (median: 17 <i>μ</i>g/m³, range: ND–130 <i>μ</i>g/m³), and compliance rate reached 99.15% (GB 37488-2019 limit: 0.10 mg/m³). Principal component analysis revealed that adsorption/desorption processes, seasonal behaviors, emission sources, and humidity are the primary drivers of VOC variability in the hotel environment. The median HQ for the four VOCs was 5.25 × 10⁻², all below 1. The median sum lifetime cancer risk for total VOCs was 2.45 × 10⁻⁵, and formaldehyde dominated the combined cancer risk.</p><p><b>Conclusion:</b> Formaldehyde is a primary pollutant in hotel air, and prolonged exposure (8 h/day, 6 days/week, and an exposure duration of 30 years) can pose a carcinogenic risk to humans. Improving ventilation and installing air purification systems are recommended to mitigate VOC exposures in the environments. However, this study has certain regional limitations in terms of geographical coverage, which may affect the generalizability of the findings.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/3747936","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145101569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Study on the Investigation of Thermal Comfort in Night Sleep Conditions","authors":"Masoumeh Mazandarani,&nbsp;Shahin Heidari","doi":"10.1155/ina/1452584","DOIUrl":"https://doi.org/10.1155/ina/1452584","url":null,"abstract":"<p>This study investigates the interplay between thermal comfort, sleep quality, and physiological responses during nocturnal rest. Despite the critical role of temperature in sleep regulation, existing thermal comfort standards fail to define specific thresholds for sleeping conditions. A three-phase experimental protocol was conducted in Tehran during the summer of 2023, involving 12 healthy adults (six men and six women, aged 28–39). Using temperature–humidity data loggers, wearable health sensors, sleep tracking software, and postsleep surveys, the study evaluated both objective and subjective indicators of sleep-related thermal comfort. Descriptive statistics, Pearson’s correlation, two-way repeated measures ANOVA, and Bonferroni’s post hoc tests were used to analyze associations between temperature, physiological responses, and perceived sleep quality. Results revealed strong correlations between bed surface temperatures, body temperature, and heart rate. Specifically, the optimal lower bed temperatures ranged from 21.70°C to 26.85°C for men and 24.76°C to 28.11°C for women, while upper bed temperatures ranged from 22.29°C to 26.24°C for men and 23.70°C to 28.41°C for women. Compared to ASHRAE and ISO 7730 daytime standards, the male temperature ranges fell within acceptable limits, while female comfort ranges exceeded these standards by approximately 1.5°C–2.5°C. These findings highlight the need for gender-specific thermal comfort guidelines in sleep environments and underscore the limitations of current standards in addressing nocturnal physiological needs.</p>","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/1452584","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145101568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Air Quality in Primary School Classrooms: Associations of PM10 and PM2.5 Levels With Outdoor and Built Environment Characteristics","authors":"Antonis Michanikou,&nbsp;Panayiotis Kouis,&nbsp;Souzana Achilleos,&nbsp;Paraskevi Kinni,&nbsp;Emily Vasiliadou,&nbsp;Chrysanthos Savvides,&nbsp;Petros Mouzourides,&nbsp;Marina K.A. Neophytou,&nbsp;Petros Koutrakis,&nbsp;Panayiotis K. Yiallouros","doi":"10.1155/ina/3809714","DOIUrl":"https://doi.org/10.1155/ina/3809714","url":null,"abstract":"&lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; Particulate matter (PM) levels in school classrooms represent a significant fraction of the daily exposure to air pollution among schoolchildren. PM levels may vary over time and may be influenced by a variety of environmental factors. However, previous studies on classrooms’ PM levels relied on short-term measurements, while relevant data from Europe remain scarce. We aimed to prospectively monitor PM&lt;sub&gt;2.5&lt;/sub&gt; (PM with aerodynamic diameter ≤ 2.5 &lt;i&gt;μ&lt;/i&gt;m) and PM&lt;sub&gt;10&lt;/sub&gt; (PM with aerodynamic diameter ≤ 10 &lt;i&gt;μ&lt;/i&gt;m) levels in school classrooms and explore their relationships with outdoor and built environment characteristics, especially during teaching periods. By addressing PM exposure during teaching periods and evaluating the effects of mitigation measures, built characteristics, and environmental factors within primary school settings in Cyprus, this study fills critical gaps in understanding particulate exposure in educational environments.&lt;/p&gt;&lt;p&gt;&lt;b&gt;Methods:&lt;/b&gt; From March to June 2021, indoor PM&lt;sub&gt;2.5&lt;/sub&gt; and PM&lt;sub&gt;10&lt;/sub&gt; concentrations were assessed prospectively using optical particle sensors, in classrooms across nine primary schools in Nicosia, Cyprus. School hours were divided into distinct teaching and recess periods to study the variations in PM levels throughout the day, as well as the effect of outdoor sources. Indoor measurements were analyzed using 2-min intervals. Corresponding time-stamped data on outdoor air pollution were obtained from the nearest air quality station. Additionally, direct, on-site comparison of indoor versus outdoor PM concentrations was possible using weekly gravimetric measurements by low-volume Harvard samplers. Data on the built environment were collected from on-site assessments and questionnaires. A linear mixed effects model was defined by fixed effects for the exposure variables and random intercepts to account for daily variations in PM levels, with additional variability between classrooms nested within each day.&lt;/p&gt;&lt;p&gt;&lt;b&gt;Results:&lt;/b&gt; Teaching periods, particularly after recess breaks, showed higher PM&lt;sub&gt;10&lt;/sub&gt; (+28.2%) and PM&lt;sub&gt;2.5&lt;/sub&gt; (+13.4%) levels than teaching periods before recess (&lt;i&gt;p&lt;/i&gt; &lt; 0.001). Outdoor pollution had the most significant impact on indoor classroom PM&lt;sub&gt;10&lt;/sub&gt; (+227.9%) and PM&lt;sub&gt;2.5&lt;/sub&gt; (+84.3%) levels (&lt;i&gt;p&lt;/i&gt; &lt; 0.001). Accessibility to soil yards led to substantially higher PM&lt;sub&gt;10&lt;/sub&gt; (86.1%) and PM&lt;sub&gt;2.5&lt;/sub&gt; (89.9%) (&lt;i&gt;p&lt;/i&gt; &lt; 0.001). Classroom windows per square meter resulted in a 10.4% lower level of PM&lt;sub&gt;10&lt;/sub&gt;, but a 5.5% higher level in PM&lt;sub&gt;2.5&lt;/sub&gt; (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Classrooms on upper floors were associated with 17.3% lower PM&lt;sub&gt;10&lt;/sub&gt; levels (&lt;i&gt;p&lt;/i&gt; &lt; 0.001). Both temperature and relative humidity were positively associated with PM levels (&lt;i&gt;p&lt;/i&gt; &lt; 0.001). The use of air purifiers significantly reduced PM&lt;sub&gt;10&lt;/sub&gt; and PM&lt;sub&gt;2.5&lt;/sub&gt; levels by 43.5% and 3","PeriodicalId":13529,"journal":{"name":"Indoor air","volume":"2025 1","pages":""},"PeriodicalIF":4.3,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1155/ina/3809714","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145058030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}