In this case study, we describe a well-resourced private school in New York City that implemented COVID-19 mitigation measures based on public health expert guidance and the lessons learned from this process. Avenues opened in New York City in 2012 and has since expanded, becoming Avenues: The World School, with campuses in São Paulo, Brazil; Shenzhen, China; the Silicon Valley, California; and online. It offers education at 16 grade levels: 2 early learning years, followed by a prekindergarten through grade 12. We describe the mitigation measures that Avenues implemented on its New York campus. We compare COVID-19 case prevalence at the school with COVID-19 case positivity in New York City, as reported by the New York State Department of Health. We also compare the school\'s indoor air quality to ambient indoor air quality measures reported in the literature. The school\'s mitigation measures successfully reduced the prevalence of COVID-19 among its students, staff, and faculty. The school also established a consistently high level of indoor air quality safety through various ventilation mechanisms, designed to reduce common indoor air pollutants. The school received positive parent and community feedback on the policies and procedures it established, with many parents commenting on the high level of trust and quality of communication established by the school. The successful reopening provides useful data for school closure and reopening standards to prepare for future pandemic and epidemic events.

Over the past decade, our understanding of the impact of air pollution on short- and long-term population health has advanced considerably, focusing on adverse effects on cardiovascular and respiratory systems. There is, however, increasing evidence that air pollution exposures affect cognitive function, particularly in susceptible groups. Our study seeks to assess and hazard rank the cognitive effects of prevalent indoor and outdoor pollutants through a single-centre investigation on the cognitive functioning of healthy human volunteers aged 50 and above with a familial predisposition to dementia. Participants will all undertake five sequential controlled exposures. The sources of the air pollution exposures are wood smoke, diesel exhaust, cleaning products, and cooking emissions, with clean air serving as the control. Pre- and post-exposure spirometry, nasal lavage, blood sampling, and cognitive assessments will be performed. Repeated testing pre and post exposure to controlled levels of pollutants will allow for the identification of acute changes in functioning as well as the detection of peripheral markers of neuroinflammation and neuronal toxicity. This comprehensive approach enables the identification of the most hazardous components in indoor and outdoor air pollutants and further understanding of the pathways contributing to neurodegenerative diseases. The results of this project have the potential to facilitate greater refinement in policy, emphasizing health-relevant pollutants and providing details to aid mitigation against pollutant-associated health risks.

Ambient ozone (O3) is recognized as a significant air pollutant with implications for cardiorespiratory health, yet the effects of indoor O3 exposure have received less consideration. Furthermore, while sleep occupies one-third of life, research on the health consequences of O3 exposure during this crucial period is scarce. This study aimed to investigate associations of indoor O3 during sleep with cardiorespiratory function and potential predisposing factors. A prospective study among 81 adults was conducted in Beijing, China. Repeated measurements of cardiorespiratory indices reflecting lung function, airway inflammation, cardiac autonomic function, blood pressure, systemic inflammation, platelet and glucose were performed on each subject. Real-time concentrations of indoor O3 during sleep were monitored. Associations of O3 with cardiorespiratory indices were evaluated using linear mixed-effect model. Effect modification by baseline lifestyles (diet, physical activity, sleep-related factors) and psychological status (stress and depression) were investigated through interaction analysis. The average indoor O3 concentration during sleep was 20.3 μg/m3, which was well below current Chinese indoor air quality standard of 160 μg/m3. O3 was associated with most respiratory indicators of decreased airway function except airway inflammation; whereas the cardiovascular effects were only manifested in autonomic dysfunction and not in others. An interquartile range increases in O3 at 6-h average was associated with changes of -3.60 % (95 % CI: -6.19 %, -0.93 %) and -9.60 % (95 % CI: -14.53 %, -4.39 %) in FVC and FEF25-75, respectively. Further, stronger effects were noted among participants with specific dietary patterns, poorer sleep and higher level of depression. This study provides the first general population-based evidence that low-level exposure to indoor O3 during sleep has greater effects on the respiratory system than on the cardiovascular system. Our findings identify the respiratory system as an important target for indoor O3 exposure, and particularly highlight the need for greater awareness of indoor air quality, especially during sleep.

Portable household air purifiers are widely used devices designed to maintain a high-quality level of indoor air. Portable air purifiers equipped with the high-efficiency air (HEPA) filter served 100 h in a household space occupied by two adults without any symptoms of respiratory tract infection. The main objective of the study was to determine microbial contamination on the HEPA filter and to investigate if the selected nanotextile monolayer made of polyamide 6 (PA6) nanofibers can capture potential microorganisms when installed downstream of the HEPA filter as the final filtration medium. Samples were taken from the inlet and outlet surfaces. Samples from the nanotextile were collected in the same manner as from the HEPA filter. QIAStat DX® 1.0 Analyzer using the Respiratory SARS CoV-2 Panel multiplex PCR detection system was selected for microorganism detection. Adenovirus was detected on the inlet surface of the HEPA filter. The outlet surface of the filter contained no viruses included in the Respiratory SARS CoV-2 Panel portfolio. The nanotextile monolayer was replaced twice during the 100 h of operation, so three pieces were used and all contained coronavirus 229 E. Coronavirus 229 E was then detected in the nasopharynx of one of the members of the household as well. It may be assumed that the selected nanotextile is capable of capturing a virus of a small size.

Creosote has been used in Sweden as a wood preservative in buildings since the 19th century. These buildings can function as workplaces, homes, and cultural buildings to which the public has access. Creosote contains polycyclic aromatic hydrocarbons (PAH) which are well known carcinogens. To understand exposure and risks in an indoor environment, it is important to determine air levels of parent PAHs as well as the more toxic nitrated and oxygenated PAH derivatives (NPAH, OPAH). This study aims to investigate indoor air levels of polycyclic aromatic compounds (PACs) e.g., PAH, NPAH, OPAH and dibenzothiophenes in buildings containing creosote sources and whether these levels pose a health risk. Four cultural buildings were studied, all located within a radius of 130 m. Two were known to have creosote sources, and two had not. Polyurethane foam passive air samplers (PUF-PAS) were used to indicate possible point sources. PUF-PAS measurements were performed for one month in each building winter and summer. Simultaneously, PAC outdoor level measurements were performed. Buildings with creosote impregnated constructions had notably higher indoor air levels of PAC (31-1200 ng m-3) compared to the two buildings without creosote sources (14-45 ng m-3). The PAH cancer potency (sum of benzo[a]pyrene equivalents (BaPeq)) was more than one order of magnitude higher in the buildings containing creosote impregnated wood compared to reference buildings. The highest value was 5.1 BaPeq ng m-3 which was significantly higher than the outdoor winter measurement (1.3 BaPeq ng m-3). Fluoranthene and phenanthrene, with significant distribution in gas phase, but also several particulate NPAHs contributed significantly to the total cancer risk. Thus, creosote containing buildings can still contaminate the indoor air with PACs despite being over a hundred years old. The PUF-PAS was shown to be a good tool providing quantitative/semiquantitative measures of PACs exposure in indoor microenvironments.

UNASSIGNED: Air conditioners (AC) have become indispensable in the contemporary World. However, their effects on respiratory health need to be explored further using dynamic and static lung functions.
UNASSIGNED: The objectives were: 1. To evaluate and compare dynamic parameters (FEV1, FVC, FEV1/FVC, PEFR, and FEF25-75) in AC users and non-users of Bengaluru. 2. To evaluate and compare airway resistance and specific airway conductance as additional parameters.
UNASSIGNED: After applying ATS-ERS criteria for lung disorders, 30 AC users and non-users of Bengaluru, aged 18-40 yrs were assessed using body plethysmography. A significant association of restrictive pattern was seen in AC users (9 AC users out of 60 participants, Chi-square 8.37, P = 0.0038) having an Odd\'s ratio of 26.95 (CI: 1.4876 to 488.3558, Z = 2.229, P = 0.0258). Airway resistance (Raw) was comparable in both groups further indicating a non-obstructive pathology.
UNASSIGNED: AC users had a significant decrease in flow rates (PEFR and FEF25-75) as well as an association with restrictive lung disorder suggesting the need for proper ventilation and hygiene. It is crucial to develop policies to maintain indoor air quality.

Contemporary life is mostly spent in indoor spaces like private houses, workplaces, vehicles and public facilities. Nonetheless, the air quality in these closed environments is often poor which leads to people being exposed to a vast range of toxic and hazardous compounds. Volatile organic compounds (VOCs) are among the main factors responsible for the lack of air quality in closed spaces and, in addition, some of them are particularly hazardous to the human organism. Considering this fact, we conducted daily in situ air analyses over 1 year using a gas chromatography-ion mobility spectrometry (GC-IMS) device in an indoor location. The obtained results show that 10 VOCs were consistently present in the indoor air throughout the entire year, making them particularly important for controlling air quality. All of these compounds were successfully identified, namely acetic acid, acetone, benzene, butanol, ethanol, isobutanol, propanoic acid, propanol, 2-propanol and tert-butyl methyl ether. The behaviour of the total VOCs (tVOCs) intensity during the period of analysis and the relative variation between consecutive months were studied. It was observed that the overall trend of tVOCs closely mirrored the variation of air temperature throughout the year suggesting their strong correlation. The results obtained from this study demonstrate the high quality and relevance of the data, highlighting the suitability of GC-IMS for in situ long-term air quality assessment in indoor environments and, consequently, for identifying potential health risks for the human organism in both short-term and long-term exposure scenarios.

There is insufficient knowledge about the systemic health effects of exposure to fine (PM2.5) and ultrafine particles emitted from typical indoor sources, including cooking and candlelight burning. We examined whether short-term exposure to emissions from cooking and burning candles cause inflammatory changes in young individuals with mild asthma. Thirty-six non-smoking asthmatics participated in a randomized controlled double-blind crossover study attending three exposure sessions (mean PM2.5 µg/m3; polycyclic aromatic hydrocarbons ng/m3): (a) air mixed with emissions from cooking (96.1; 1.1), (b) air mixed with emissions from candles (89.8; 10), and (c) clean filtered air (5.8; 1.0). Emissions were generated in an adjacent chamber and let into a full-scale exposure chamber where participants were exposed for five hours. Several biomarkers were assessed in relation to airway and systemic inflammatory changes; the primary outcomes of interest were surfactant Protein-A (SP-A) and albumin in droplets in exhaled air - novel biomarkers for changes in the surfactant composition of small airways. Secondary outcomes included cytokines in nasal lavage, cytokines, C-reactive protein (CRP), epithelial progenitor cells (EPCs), genotoxicity, gene expression related to DNA-repair, oxidative stress, and inflammation, as well as metabolites in blood. Samples were collected before exposure start, right after exposure and the next morning.
SP-A in droplets in exhaled air showed stable concentrations following candle exposure, while concentrations decreased following cooking and clean air exposure. Albumin in droplets in exhaled air increased following exposure to cooking and candles compared to clean air exposure, although not significant. Oxidatively damaged DNA and concentrations of some lipids and lipoproteins in the blood increased significantly following exposure to cooking. We found no or weak associations between cooking and candle exposure and systemic inflammation biomarkers including cytokines, CRP, and EPCs.
Cooking and candle emissions induced effects on some of the examined health-related biomarkers, while no effect was observed in others; Oxidatively damaged DNA and concentrations of lipids and lipoproteins were increased in blood after exposure to cooking, while both cooking and candle emissions slightly affected the small airways including the primary outcomes SP-A and albumin. We found only weak associations between the exposures and systemic inflammatory biomarkers. Together, the results show the existence of mild inflammation following cooking and candle exposure.

Using air purifiers is an intervention to reduce exposure to fine particulate matter (PM2.5) for health benefits. We performed a comprehensive simulation in urban China to estimate the cost-effectiveness of long-term use of air purifiers to remove indoor PM2.5 from indoor and ambient air pollution in five intervention scenarios (S1-S5), where the indoor PM2.5 targets were 35, 25, 15, 10, and 5 μg/m3, respectively. In scenarios S1 to S5, 5221 (95% uncertainty interval: 3886-6091), 6178 (4554-7242), 8599 (6255-10,109), 11,006 (7962-13,013), and 14,990 (10,888-17,610) thousand disability-adjusted-life-years (DALYs) can be avoided at the cost of 201 (199-204), 240 (238-243), 364 (360-369), 522 (515-530), and 921 (905-939) billion Chinese Yuan (CNY), respectively. A high disparity in per capita health benefits and costs was observed by city, which expanded with the decrease of the indoor PM2.5 target. The net benefits of using purifiers in cities varied across scenarios. Cities with a lower ratio of annual average outdoor PM2.5 concentration to gross domestic product (GDP) per capita tended to achieve higher net benefits in the scenario with a lower indoor PM2.5 target. Controlling ambient PM2.5 pollution and developing the economy can reduce the inequality in air purifier use across China.

OBJECTIVE: To investigate the effect of CO2 during sleep on next-morning cognitive performance in young schoolchildren, the authors performed a double-blind fully balanced crossover placebo-controlled study.
METHODS: The authors included 36 children aged 10-12 years in the climate chamber. The children slept at 21°C in 6 groups each at 3 different conditions separated by 7 days in a random order. Conditions were as follows: high ventilation with CO2 at 700 ppm, high ventilation with added pure CO2 at 2000-3000 ppm, and reduced ventilation with CO2 at 2-3000 ppm and bioeffluents. Children were subjected to a digital cognitive test battery (CANTAB) in the evening prior to sleep and on the next morning after breakfast. Sleep quality was monitored with wrist actigraphs.
RESULTS: There were no significant exposure effects on cognitive performance. Sleep efficiency was significantly lower at high ventilation with CO2 at 700 ppm which is considered to be a chance effect. No other effects were seen, and no relation between air quality during sleep and next-morning cognitive performance was observed in the children emitting an estimated 10 lCO2/h per child.
CONCLUSIONS: No effect of CO2 during sleep was found on next day cognition. The children were awakened in the morning, and spent from 45-70 min in well-ventilated rooms before they were tested. Hence, it cannot be precluded that the children have benefitted from the good indoor air quality conditions before and during the testing period. The slightly better sleep efficiency during high CO2 concentrations might be a chance finding. Hence, replication is needed in actual bedrooms controlling for other external factors before any generalizations can be made. Int J Occup Med Environ Health. 2023;36(2):177-91.