Interventions for improving indoor and outdoor air quality in and around schools

Improving classroom air quality and ventilation with IoT-driven acoustic and visual CO2 feedback system

In naturally ventilated classrooms, the air quality and ventilation conditions rely heavily upon window and door opening behaviour of the class teacher. This study aimed to examine the impact of an Internet of Things (IoT)-based CO₂ self-surveillance display system (SAVE unit) on classroom air quality and thermal comfort. The visual-acoustic signalling of classroom ventilation conditions notified the class teacher for opening/closing of classroom doors and windows. The air quality data were collected across baseline (no alarm), S1 (visual alarm) and S2 (visual-acoustic alarm) scenarios. The alarm was triggered to notify a class teacher when CO₂ exceeded 1000 and 1500 ppm with different alarm schemes. Results showed a 19.5 % reduction in CO₂ with visual alarms and 19 % with visual-acoustic alarms. However, PM concentrations (PM₁₀, PM₂.₅, PM₁, PM₀.₁) increased due to window openings, though a daily average of PM₁₀ and PM₂.₅ remained within WHO safe limits. Teacher's decision to open or close windows was primarily influenced by classroom temperature. Higher CO2 concentration was observed during colder days (S2) due to windows kept closed to avoid uncomfortable classroom temperature and excessive use of heaters. The SAVE unit helped to effectively lowered CO₂, but it also led to higher energy consumption due to heat loss from open windows. While natural ventilation improved air quality, it highlighted the need for balancing energy efficiency and thermal comfort. A holistic signalling system that integrates temperature, air quality, and ventilation parameters would better guide teachers in managing classroom ventilation. Additionally, a school-level ventilation protocol based on IoT-based signalling is recommended to ensure consistent and effective air quality management. This study underscores the importance of real-time data-driven ventilation strategies to optimise indoor air quality, reduce exposure to pollutants, and maintain a comfortable learning environment in classrooms.

Exposure to BTEX concentrations in different indoor microenvironments: Emphasis on different times of the year

Climatic variations in indoor environments may change concentration patterns. This systematic review and meta-analysis study aimed to investigate exposure to benzene, toluene, ethylbenzene, and xylene (s) (BTEX) concentrations in different indoor microenvironments with emphasis on different times of the year. A systematic review in five bibliographic databases (Scopus, PubMed, Web of Science, Embase, and Medline) was conducted. Adhering to PRISMA guidelines, the search utilized four groups of keywords. The pooled indoor exposure to BTEX under different climatic conditions were estimated using a random-effects model. Among 64 selected articles, the greatest percentage of studies with the highest indoor exposure for BTEX in vehicles and transportation areas was in summer. The highest percentage of these studies at home was in winter. The highest percentage of these studies in educational and sport centers was in winter and summer. In the vehicles and transportation areas, the pooled concentration (µg/m3) of benzene, toluene, ethylbenzene, and xylene(s) were calculated as 29.12, 102.33, 19.24, and 22.73 in summer, respectively. In the homes and sites, the pooled concentration (µg/m3) of benzene, toluene, ethylbenzene, and xylene(s) were measured as 6.39, 22.06, 6.21, and 11.33 in winter, respectively. In the educational and sport centers, the pooled concentration (µg/m3) of benzene, toluene, ethylbenzene, and xylene(s) were calculated as 3.15, 11.09, 5.55, and 5.63 in summer and 2.97, 8.09, 4.16, and 5.49 in winter, respectively. The results of this study introduce the seasons with the greatest concentrations of BTEX in different indoor environments.

Demonstrating multi-benefits of green infrastructure to schools through collaborative approach

Green infrastructure (GI) is known to reduce road air pollution exposure, but their implementation in schools and associated benefits remain under-researched. In this study, two GI solutions, green screen and green gate, were co-designed and installed at a primary school in Guildford using collaborative and participatory methods. By assessing changes in air pollution levels, noise, and public perception before and after GI installation, we aimed to understand their impact on reducing children's exposure and evaluate other co-benefits. Without considering wind direction's effect, a maximum reduction of up to 32 %, 10 % and 12 % in the average daily concentration of PM10 (green gate), PM2.5 (green screen) and PM1 (green gate), respectively, when compared with in-front concentration. The decay in concentration decreases with distance from the GI, and different wind directions result in varying percentage reductions in PM concentration. For the green screen, 'parallel to the screen' and for the green gate, 'away from the gate' wind directions provided the highest PM reduction. The horizontal abatement efficiency of GI varied with PM size, with the highest being PM10. Continuous monitoring behind the green screen revealed a decrease in PM concentration after installation, and this relative concentration varied from 0.29 to 0.90 compared to before installation. The green gate effectively lowered noise by 5 dB(A), and the green screen did not report a noticeable impact on noise levels. Most parents perceived the installation of GI in school as significantly decreasing air pollution exposure and slightly reducing noise levels, resembling the changes in their levels observed in monitoring. The successful co-creation and co-implementation of GI interventions and resulting co-benefits underscore the importance of community engagement and participatory approaches in urban planning and environmental management. This study paves the way for the wider-scale application of innovative strategies involving local communities, stakeholders, and policymakers in implementing GI projects to ensure their sustainability and effectiveness.

Seasonal Characterization of the Aerobiome in Hematopoietic Stem Cell Transplant Rooms: Potential Risk for Immunosuppressed Patients

Infections pose a risk for patients undergoing hematopoietic stem cell (HSC) transplants due to their immunosuppression, making them susceptible to opportunistic infections. Therefore, understanding the composition of the aerobiome in this area is vital. The aim of this study was to characterize the aerobiome in an HSC transplant area, evaluating the impact of infrastructure and health personnel operations on air contamination. The environmental parameters and aerobiome of the HSC transplant area at Hospital Juárez de México were quantified over one year. Finally, a double-entry Vester matrix was constructed to classify problems according to their degree of causality. The abundance and taxonomic diversity of the aerobiome were dependent on seasonality, environmental factors, and high-efficiency filtration. Gram-positive bacteria predominated, followed by fungi and Gram-negative bacteria. ANOVA revealed significant differences in the bacterial aerobiome but not in the fungal aerobiome among the transplant rooms. Clinically, fungi such as Aspergillus fumigatus, Alternaria spp., Cladosporium spp., and Penicillium spp. were identified. ESKAPE bacteria typing revealed clonal dispersion. Finally, the Vester matrix highlighted critical problems associated with contamination due to the absence of HEPA filtration and non-adherence in patient management practices. HEPA filtration and positive pressure are essential to improve the air quality and reduce the microbiological load. However, the control areas will depend on patient management and routine activities, such as entry protocols in controlled areas.

Strategies to reduce air pollution emissions from urban residential buildings

As cities continue to grow, developing mitigation strategies is crucial to minimize the corresponding increase in air pollutants. One source of potentially controllable air pollution is the emissions from residential buildings. We conducted a literature review to systematically examine air pollution emissions from residential buildings in urban areas, identifying pollutants and their sources; investigated mitigation-aimed intervention types by field of application or study, and finally listed and discussed strategies to reduce the concentration of air pollutants in residential buildings. Our compilation shows that among the nature-based solutions, green walls offered the highest relative reduction of air pollution (-15 % NO2 and -23 % PM10). Of the construction-based solutions, already-available photocatalytic paint can achieve reductions of 25 % NO, 23 % NOx and 19 % NO2 as is. Industrial-based solutions promise high levels of reduction, but these must be adapted to residential buildings. The integration of various existing and potentially adapted mitigation solutions may achieve even higher pollution reduction rates in urban areas.

Unseen crisis: Revealing the hidden health impact of indoor air pollution-A scoping review

Indoor air pollution presents a critical public health challenge, particularly in countries such as India, where millions are exposed to harmful pollutants within their homes and workplaces. This scoping review delves into the multifaceted impacts of indoor air pollution on health outcomes, synthesizing evidence from various study designs and geographical regions A scoping review was conducted. Drawing on a comprehensive search strategy, which yielded 320 records, wherein 120 in PubMed, 108 in Web of Science, and 92 in SCOPUS. Ten studies were selected based on predefined inclusion criteria, totaling a sample size of 37,43166 individuals. The synthesis of findings from the selected studies reveals the multifaceted impact of indoor air pollution on health status. Respiratory symptoms and illnesses were found to be prevalent among individuals exposed to indoor pollutants, with biomass fuel combustion posing a particularly high risk for chronic obstructive pulmonary disease (COPD) in women. In addition, indoor air pollution was associated with adverse pregnancy outcomes, cardiovascular diseases, central nervous system impacts, cognitive impairment, and developmental delays. Urgent action is needed to reduce indoor air pollution, safeguard health, and promote cleaner technologies for healthier indoor environments. Vulnerable populations, such as women, children, and the elderly, are disproportionately affected by indoor pollutants, highlighting the importance of targeted interventions and policies.

Volatile organic compounds and cancer risk assessment in an intensive care unit

Changes caused by air-cleaning devices in the amounts of volatile organic compounds in an intensive care unit were monitored in the study. The cancer risk and hazard index were calculated. The measurements were made for one month at isolated room and two different points and times in the intensive care unit. According to the sampling program, the air-cleaning devices were turned off in weeks 1 and 4 and turned on in weeks 2 and 3. Volatile organic compounds were collected by active sampling. Samples were analyzed by a thermal desorber coupled to a gas chromatography-mass spectrometry instrument with selective ion monitoring. The results showed that the concentrations of benzene, toluene, and o-xylene decreased by about 70% after the air-cleaning devices were installed. The cancer risk assessment for naphthalene was recorded at the highest level of cancer risk (Class A). The hazard index value of naphthalene was recorded at the harmful level when air-cleaning devices were not installed. The concentrations of benzene (p = 0.01), toluene (p = 0.02), ethylbenzene (p = 0.02), styrene (p = 0.01), and m, p-xylene (p = 0.04) before the air-cleaning devices were installed were significantly different from those recorded when the air-cleaning devices were turned on.

Breathing in danger: Understanding the multifaceted impact of air pollution on health impacts

Air pollution, a pervasive environmental threat that spans urban and rural landscapes alike, poses significant risks to human health, exacerbating respiratory conditions, triggering cardiovascular problems, and contributing to a myriad of other health complications across diverse populations worldwide. This article delves into the multifarious impacts of air pollution, utilizing cutting-edge research methodologies and big data analytics to offer a comprehensive overview. It highlights the emergence of new pollutants, their sources, and characteristics, thereby broadening our understanding of contemporary air quality challenges. The detrimental health effects of air pollution are examined thoroughly, emphasizing both short-term and long-term impacts. Particularly vulnerable populations are identified, underscoring the need for targeted health risk assessments and interventions. The article presents an in-depth analysis of the global disease burden attributable to air pollution, offering a comparative perspective that illuminates the varying impacts across different regions. Furthermore, it addresses the economic ramifications of air pollution, quantifying health and economic losses, and discusses the implications for public policy and health care systems. Innovative air pollution intervention measures are explored, including case studies demonstrating their effectiveness. The paper also brings to light recent discoveries and insights in the field, setting the stage for future research directions. It calls for international cooperation in tackling air pollution and underscores the crucial role of public awareness and education in mitigating its impacts. This comprehensive exploration serves not only as a scientific discourse but also as a clarion call for action against the invisible but insidious threat of air pollution, making it a vital read for researchers, policymakers, and the general public.

Exploring Strategies to Mitigate the Adverse Health Impacts of Air Pollution on Children in India: A Qualitative Study

BACKGROUND

Air pollution poses a significant threat to global public health, contributing to high rates of mortality and morbidity. India, home to the world's largest population of children, is particularly affected. This study aims to identify effective strategies to mitigate the adverse health impacts of air pollution on this vulnerable group.

MATERIAL AND METHODS

The study utilized directed content analysis using a deductive approach and purposeful sampling to carry out in-depth interviews with researchers, academicians, paediatricians, public health experts, and climate change experts from different organizations in India. In total, 17 interviews were conducted over two months in March and April 2024 until data saturation was reached.

RESULTS

 A total of 29 subcategories were extracted. The main sub-categories include strategies for reducing indoor emissions and multisectoral emission reduction, strategies to reduce exposure at home, schools and transit, strategies for public awareness, effective communication, health sector communication and awareness, and raising awareness by frontline workers and educational institutions, strategies for capacity building of health sector and frontline stakeholders, strategies for building research and knowledge translation, strategies for vertical and horizontal collaboration, strategies for child-centric policies, school closure policies, fiscal policies, comprehensive policymaking, sectoral policymaking, advocacy in policymaking, strategies for monitoring, and strategies for mother and child health.

CONCLUSIONS

The results of this study indicate that mitigating the adverse health impacts of pollution for children would entail a multi-pronged approach encompassing effective communication and education strategies and awareness raising of important stakeholders such as health professionals, community, grassroots-level workers, parents, teachers and children. Such strategies could be useful to trigger the desired change in behaviour of all concerned. Also, there is a need for collaboration and partnership between various stakeholders and ministries as policy-making bodies. There is a need to build on the research and strengthen the monitoring and surveillance.

Associations between community green view index and fine particulate matter from Airboxes

Urban greenery can help to improve air quality, reduce health risks and create healthy livable urban communities. This study aimed to explore the role of urban greenery in reducing air pollution at the community level in Tainan City, Taiwan, using air quality sensors and street-view imagery. We also collected the number of road trees around each air quality sensor site and identified the species that were best at absorbing PM2.5. Three greenness metrics were used to assess community greenery in this study: two Normalized Difference Vegetation Indices (NDVI) from different satellites and the Green View Index (GVI) from Google Street View (GSV) images. Land-use Regression (LUR) was used for statistical analysis. The results showed that a higher GVI within a 500 m buffer was significantly associated with decreased PM2.5. Neither NDVI metrics within a 500 m circular buffer were significantly associated with decreased PM2.5. Evergreen trees were significantly associated with lower ambient PM2.5, compared with deciduous and semi-deciduous trees. Because localized changes in air quality profoundly affect public health and environmental equity, our findings provide evidence for future urban community greenspace planning and its beneficial impacts on reducing air pollution.