School Indoor Air Research Articles

COVID-19 Mitigation in a K-12 School Setting: A Case Study of Avenues: The World School in New York City.

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.

Radon gas in indoor air of primary schools of Al-Najaf city, Iraq

The indoor radon concentration of 100 primary schools in Al-Najaf province, Iraq, was measured to determine students’ and staff's safety in these schools using a CR-39 nuclear track detector based on the sealed can improve technique. The results of indoor radon concentration for all schools vary from (7.47 to 44.84) Bq / m3 with an arithmetic mean (AM) of 22.26 Bq /, while the geometric mean (GM) was 20.67 Bq / m3. The concentration of 222Rn was lower than the worldwide level. Some radiological parameters like annual effective dose (AED), potential alpha energy (PAEC), exposure to radon progeny (EP), and lung cancer cases per year per million people (CPPP) were also determined. The results of these parameters point toward normal levels in the primary schools, according to ICRP, UNCER, and NCRP data.

The level of PM2.5 and potentially toxic elements (PTEs) in PM2.5 in the indoor air of urban schools: systematic review-meta-analysis

The level of PM2.5 and potentially toxic elements (PTEs) in PM2.5 in the indoor air of urban schools: systematic review-meta-analysis

The concentration of potentially toxic elements (zinc, iron, manganese) bound PM2.5 in the indoor air of urban schools: a global systematic review and meta-analysis

The concentration of potentially toxic elements (zinc, iron, manganese) bound PM2.5 in the indoor air of urban schools: a global systematic review and meta-analysis

BTEX exposure in indoor air in schools in Bulgaria

Exposure to indoor air pollutants is one of the primary environmental health stressors, the most important categories of chemicals that occur in the indoor air are BTEX (benzene, toluene, ethylbenzene and xylenes). All of them are used in many commercial building products and materials use indoor. Each of the chemicals in the mixture of concern is volatile, well absorbed, extensively metabolized, and does not persist in the body for long periods of time. All of the BTEX chemicals can produce neurological impairment. The aim of this work is on research and analysis of indoor air quality. seasonal fluctuations and to assess the impact of chemical pollutants in a closed environment in southwest Bulgaria.

Volatile Organic Compounds in Finnish Office Environments in 2010-2019 and Their Relevance to Adverse Health Effects.

We gathered recent (2010–2019) data on the VOC and formaldehyde levels in Finnish non-industrial indoor work environments. The data comprised 9789 VOC and 1711 formaldehyde samples collected from the indoor air of offices, schools, kindergartens, and healthcare offices. We assessed the health risks by comparing the measured concentrations to the health-based RW I/II and EU-LCI reference values. The concentrations of individual VOCs and formaldehyde in these work environments were generally very low and posed no health risks. Total VOC concentration (TVOC) as well as concentrations of several individual compounds, including aromatic compounds, alkanes, 2-ethyl-1-hexanol, and formaldehyde, showed clearly decreasing trends. In contrast, several aldehydes, acids, and a few other compounds showed increasing trends. However, the increasing trends did not seem to affect the higher ends of the distributions, as the 95th percentile values remained fairly stable or decreased over the years. The VOC patterns in the environments of the offices, schools, kindergartens, and healthcare offices varied, probably reflecting the differences in typical activities and the use of materials. However, we do not expect these differences to be relevant to health outcomes.

Toxicity Assessment of 91-Day Repeated Inhalation Exposure to an Indoor School Air Mixture of PCBs.

School indoor air contaminated with polychlorinated biphenyls (PCBs) released from older building materials and paint pigments may pose health risks to children, as well as teachers and staff, by inhalation of PCBs. The health effects of long-term inhalation exposure to PCBs are poorly understood. We conducted a comprehensive toxicity assessment of 91-day repeated inhalation exposure to a lab-generated mixture of PCBs designed to emulate indoor school air, combining transcriptomics, metabolomics, and neurobehavioral outcomes. Female Sprague-Dawley rats were exposed to school air mixture (SAM+) at a concentration of 45.5 ± 5.9 μg/m3 ∑209PCB or filtered air 4 h/day, 6 days/week for 13 weeks using nose-only exposure systems. The congener-specific PCB body burden was quantified in major tissues using GC-MS/MS. The generated SAM+ vapor recapitulated the target school air profile with a similarity coefficient, cos θ of 0.91. PCB inhalation yielded 875-9930 ng/g ∑209PCBlipidweight levels in tissues in the following ascending order: brain < liver < lung < serum < adipose tissue. We observed that PCB exposure impaired memory, induced anxiety-like behavior, significantly reduced white blood cell counts, mildly disrupted metabolomics in plasma, and influenced transcription processes in the brain with 274 upregulated and 58 downregulated genes. With relatively high exposure and tissue loading, evidence of toxicity from half the end points tested was seen in the rats.

Non-dioxin-like polychlorinated biphenyl neurotoxic equivalents found in environmental and human samples

Non-dioxin like polychlorinated biphenyls (NDL PCB) are recognized neurotoxicants with implications on altered neurodevelopment and neurodegeneration in exposed organisms. NDL PCB neurotoxic relative potency schemes have been developed for a single mechanism, namely activity toward the ryanodine receptor (RyR), or combined mechanisms including, but not limited to, alterations of RyR and dopaminergic pathways. We compared the applicability of the two neurotoxic equivalency (NEQ) schemes and applied each scheme to PCB mixtures found in environmental and human serum samples. A multiple mechanistic NEQ predicts higher neurotoxic exposure concentrations as compared to a scheme based on the RyR alone. Predictions based on PCB ortho categorization, versus homologue categorization, lead to a higher prediction of neurotoxic exposure concentrations, especially for the mMOA. The application of the NEQ schemes to PCB concentration data suggests that PCBs found in fish from US lakes represent a considerable NEQ exposure to fish consuming individuals, that indoor air of schools contained high NEQ concentrations representing an exposure concern when inhaled by children, and that levels already detected in the serum of adults and children may contribute to neurotoxicity. With further validation and in vivo exposure data the NEQ scheme would help provide a more inclusive measure of risk presented by PCB mixtures.

Microbial pollution of indoor air in Riyadh city government schools

The presence of microorganisms in indoor air represents a dangerous issue with a major impact in the field of health protection and environmental engineering. Low indoor air quality is a major trouble in government schools because of the massive density of students per classroom, inadequate supply of air from outside, as well as weak construction and poor maintenance of school buildings. Evaluation of microbial contamination within the indoor air is important to assess health dangers and establish requirements for tracking indoor air quality. Evaluation of microbial contamination is of notable significance in intensively populated centers as government schools. A study was carried out among a hundred and twenty randomly classrooms of twenty government primary schools of Riyadh city in the academic year 2018/2019. For the determination of microbial pollution, passive air sampling settle plate technique was utilized by exposing a Petri dish of appropriate agar media for one hour. Results showed that the counts of bacteria and fungi were higher in government schools in low socioeconomic districts as compared to those of high socioeconomic districts. The indoor analyses reveal that the concentration of bacteria was higher than counts of fungi. In general, Gram positive microorganisms were the dominant organisms. Gram positive bacteria, Bacillus, Micrococci and Staphylococci were the predominant bacterial strains in the schools under study. Attention has to be paid for controlling the physical factors that assist the growth and reproduction of microbes in indoor air of classrooms to keep the students and teachers healthy.

Microbial pollution of indoor air in Riyadh city government schools

Microbial pollution of indoor air in Riyadh city government schools

Level of particulate matter pollution in the indoor and outdoor air of primary schools of Bandar Abbas, Iran Abbas, Iran

Introduction: Air pollution in primary schools is a concerning issue, because young students, as a sensitive group, are present in such enclosed environments. The aim of this study was to deterrmine the level of particulate matter pollution in indoor and outdoor air of primary schools in Bandar Abbas, Iran. Methods: In this descriptive-analytical study, during 9 sampling runs form winter to spring of 2018, the concentrations of particulate mattere with aerodynamic diameters below or equal to 10 (PM10) and 2.5 µm (PM2.5) were measured in indoor and outdoor air of 10 governmental primary schools of Bandar Abbas city using a HazDust-EPAM-5000 sampler. The PM10 and PM2.5 concentrations were analyzed by Excel software and the mean and standard deviation values of the concentrations were calculated. The correlation between the concentration of particulate matter (PM) in indoor and outdoor environments was evaluated by SPSS software using spearman test at a confidence level of 95%. Moreover, Wilcoxon test was used for comparing the mean concentrations of particulate matters in indoor and outdoor air of the schools. Results: The values of 10-min mean concentrations of PM2.5 and PM10 in indoor air of schools were 78.8±36.8 and 111.1±53.0 µg/m3 , respectively, while these values for outdoor air were 72.3±34.9 and 100.2±47.2 µg/m3 , respectively. The mean indoor/outdoor ratios for PM2.5 and PM10 were 1.24 and 1.23, respectively. Statistical analysis showed that there was a significant difference between the PM concentrations in indoor and outdoor of the schools. Conclusion: The PM concentration in indoor air of primary schools in Bandar Abbas was higher than that of the ambient air, which may be due to the resuspension of deposited dusts through student activities. Accordingly, more efforts are needed for frequently cleaning of the indoor environment in the primary schools.

ارزيابی غلظت بيوآئروسل¬ها در هوای داخلی و هوای آزاد مدارس و مهدکودک های انديمشک درطول زمستان سال 1394

ارزيابی غلظت بيوآئروسل¬ها در هوای داخلی و هوای آزاد مدارس و مهدکودک های انديمشک درطول زمستان سال 1394

The study of indoor concentrations of organic compounds in school classrooms and accumulated blood xenobiotic levels in children

The analysis of multicomponent chemical composition of atmospheric air and the air of residential and public premises, including school indoor air, is an urgent task of modern hygienic studies devoted to environmental quality and risk assessment of adverse health effects of dangerous chemicals. The priority sources of air pollution inside classrooms are finishing materials (linoleum, wallpaper, varnishes, paints, etc.) and emissions of monomers from furniture made of chipboards processed with polymer resins. The article demonstrates the results of screening tests establishing the levels of airborne toxic organic compounds (phenol, formaldehyde, benzene, toluene, ethylbenzene, and xylene) both inside and outside educational premises affected by various environmental exposures (conditional areas of observation and comparison). To assess the chemical body burden, blood levels of certain chemicals were measured in schoolchildren dwelling in the observation (study) and comparison (control) areas. Blood tests were accompanied by indoor and outdoor air monitoring in the educational establishments. We examined the total of 424 children including 231 students from primary, secondary and high schools of the city of Perm (observation area) and 193 schoolchildren of grades 1–11 living in the town of Kungur (comparison area). We established that the average daily concentrations of phenol and formaldehyde in indoor air in Perm were 2.4 and 5.6 times higher (р &lt; 0.05) than those in Kungur. Outdoor concentrations of phenol and formaldehyde in Perm were 2.6 and 3.7 times higher than those in Kungur. The analysis of blood levels of certain organic compounds in the primary, secondary and high school children in Perm showed significantly higher concentrations of phenol, benzene, and toluene (p &lt; 0.05) (1.5, 1.1, and 1.2 times, respectively). The average blood concentration of formaldehyde in the study group was 1.3 times higher (p &lt; 0.05) than that in children of the comparison area. No significant differences between the comparison and observation groups (p &lt; 0.05) were found in blood levels of xylene and ethylbenzene. Children’s blood concentrations of the identified organic compounds indicate the presence of external sources of exposure to these toxicants.

Indoor exposure to bioaerosol particles: levels and implications for inhalation dose rates in schoolchildren

Children spend most of their time inside schools and bioaerosol particles are part of their everyday environment. Although bioaerosol particles are considered to be a potential risk factor for various health concerns, information concerning the indoor exposures and inhalation doses is still limited. This study aimed (i) to quantify bacterial and fungal particles levels in indoor and outdoor air of public primary schools, (ii) to assess the influence of ambient air on bacteria and fungi presence indoors, and (iii) to estimate the inhalation dose rates for respective children (8–10 years old) in comparison with adult staff. Air samples were collected in 20 primary schools in a total of 71 classrooms during heating season with a microbiological air sampler. The results showed that indoor bacterial and fungal concentrations were higher than outdoor levels (p < 0.05), which could be explained by differences in density of occupation, occupant’s activities, and inadequate ventilation. CO2 levels were significantly correlated with indoor bacteria concentrations. Moreover, mean indoor bacteria concentrations were above national limit values in all the evaluated Porto primary schools, from two to nine times higher. Regarding fungi concentrations, indoor levels were above the reference value in 75% of the schools and overall indoor levels registered a 3-fold increase compared with outdoor values. Children had two times higher inhalation dose rates to bioaerosol particles when compared to adult individuals. Thus, due to their susceptibility, special attention should be given to educational settings in order to guarantee the children healthy development.

Characterization and cancer risk assessment of VOCs in home and school environments in gran La Plata, Argentina.

Three areas are highlighted in Gran La Plata, Argentina: industrial, urban, and residential. In this work, the levels of volatile organic compounds (VOCs) in indoor air of homes and schools in those areas were analyzed, through the use of passive monitors. The study period is between 2007 and 2010. Higher levels of VOCs were found in homes and schools in the industrial zone, higher than the levels corresponding to urban and residential. Taking into account the relationship between indoor and outdoor levels of VOCs, they have ratios (I/O) between 1.5 and 10 are evidenced contributions of emission sources of VOCs both indoor and outdoor. Complementarily, we estimated the life time cancer risk (LCR) for benzene, styrene, trichloroethylene, and tetrachloroethylene in children who spend their time mostly in such indoor environments. The results show high LCR values for benzene, which exceed acceptable values for the US EPA.

Effects of room airflow on accurate determination of PUF-PAS sampling rates in the indoor environment.

Accurate and precise interpretation of concentrations from polyurethane passive samplers (PUF-PAS) is important as more studies show elevated concentrations of PCBs and other semivolatile air toxics in indoor air of schools and homes. If sufficiently reliable, these samplers may be used to identify local sources and human health risks. Here we report indoor air sampling rates (Rs) for polychlorinated biphenyl congeners (PCBs) predicted for a frequently used double-dome and a half-dome PUF-PAS design. Both our experimentally calibrated (1.10 ± 0.23 m3 d-1) and modeled (1.08 ± 0.04 m3 d-1) Rs for the double-dome samplers compare well with literature reports for similar rooms. We determined that variability of wind speeds throughout the room significantly (P < 0.001) effected uptake rates. We examined this effect using computational fluid dynamics modeling and 3-D sonic anemometer measurements and found the airflow dynamics to have a significant but small impact on the precision of calculated airborne concentrations. The PUF-PAS concentration measurements were within 27% and 10% of the active sampling concentration measurements for the double-dome and half-dome designs, respectively. While the half-dome samplers produced more consistent concentration measurements, we find both designs to perform well indoors.

Impact of School Air Quality on Children's Respiratory Health.

Background:Asthma is common in children with indoor pollutants influencing the development of the disease. Since children spend most of their time outside their homes within the school environment, school indoor air quality can directly influence their respiratory health.Aims:This study aims to analyze the indoor and outdoor air quality of Maltese schools and if an association exists between indoor pollutants and respiratory health in children.Settings and Design:Five primary schools were selected with 9- to 11-year-old students participating.Materials and Methods:Standardized health questionnaires and lung function tests were utilized. Indoor and outdoor air sampling together with traffic counts were carried out.Statistical Analysis Used:SPSS version 21 was used and the Chi-squared, logistic regression, and Pearson's correlation were used.Results:The mean indoor PM 2.5 level of 17.78 μg/m3 and CO (9.11 ppm) exceeded World Health Organization thresholds. Indoor ozone levels exceeded the mean European school's indoor ozone concentration of 8 μg/m3. High exposure to formaldehyde, NO2, and ozone was associated with atopy in children. Heavy vehicles passing near the schools were associated with current wheezing (P < 0.001) but not nocturnal cough (P = 0.34).Conclusions:School indoor and outdoor environment has a direct impact on children's respiratory health. This study has identified significant associations between high exposures to indoor air pollutants, school characteristics, and upper and lower airway inflammation.

Bacterial Contamination of Indoor Air in Schools of Riyadh, Saudi Arabia

Background: The presence of bacteria in the indoor air pose a serious problem from the point of view of health protection and environmental engineering. Precise determination of various groups of bacteria indoors is necessary for both to estimate the health hazard and to create standards for indoor air quality control. This is especially important in such densely populated facilities like educational institutions. Results: In the present study, 252 samples of indoor air and air conditioners of 25 schools (Middle Schools) Public and Special, those were collected from east and centre of Riyadh in, Saudi Arabia, between October and November 2015. The most common bacterial isolates were, Gram negative bacteria (Pseudomonas stutzeri, Francisella tularensis and Ralstonia mannitolilytica ) of the total airborne bacteria. Whereas, the prevailing Gram positive bacteria were the Staphylococcus aureus, followed by Kocuria kristinae. Also, Pseudomonas stutzeri was isolated from the air conditioners of special schools. Results revealed that the highest level of bacterial contamination was detected in the class rooms during lessons. Conclusions: High concentrations of bacteria was observed in the public schools (where overcrowded classrooms). Results obtained in this study showed that the bacterial species varied in their susceptibility to all the antimicrobials used. Majority of them showed resistance to one or more of antimicrobials compounds. It was observed that Ciprofloxacin was the most effective antibiotic to all bacterial species used during this study.

The Impact of Microbiological Pollutants on School Indoor Air Quality

Asthma is common in children with allergens and mould influencing the development of the disease. Since children spend most of their time outside their homes within the school environment, school indoor air quality can directly influence their respiratory health. This study aims to identify microbiological contaminants in Maltese schools. The association between contaminants, respiratory health and school characteristics has been analysed. Five primary schools were selected with 9 to 11 years old students participating. Standardised health questionnaires, lung function tests, and school characterisation were performed. Dust samples were analysed for fungi, bacteria and allergens were performed. Penicillium/Aspergillus/Paecilomyces/Variotii (PenAsp) group had the highest median indoor concentration followed by Mycobacterial and Streptomyces species. There was a significant negative correlation between PenAsp and Mycobacterium spp levels in all the participating schools (r = ?0.42; p = 0.03). Cat allergen in classroom dust correlated positively with the number of cat owners (r = 0.43; p = 0.041). High exposure to fungi, bacteria and allergens was significantly associated with upper and lower airway atopy. School/classroom characteristics and cleaning protocols were significantly associated with exposure to these pollutants. In conclusion, fungi, bacteria, endotoxin, cat and dog allergens have been found to have a direct influence on school indoor air quality in the Maltese Islands. A significant association was observed between these contaminants and upper and lower airway atopy. Specific school, classroom, cleaning and maintenance characteristics have been identified as having a direct impact on indoor air quality.

Applying the Social Ecological Model to Creating Asthma-Friendly Schools in Louisiana.

In 2010, the Louisiana Asthma Management and Prevention Program (LAMP) implemented the Asthma-Friendly Schools Initiative in high-risk Louisiana populations. The social ecological model (SEM) was used as a framework for an asthma program implemented in 70 state K-12 public schools over 2 years. Activities included a needs assessment, identification of students with asthma, individualized asthma action plans (AAP), staff trainings, environmental quality improvement, and school system policy changes to address the asthma burden. There were 522 new or existing asthma cases recognized. Asthma knowledge/awareness was measurably improved among school personnel. School indoor air quality was improved across all locations. School-level policies were adopted that improved AAP collection, compliance to bus-idling restrictions, and asthma medication self-carry. The SEM framework can be used for school-based programs to address successfully and improve asthma-related issues from the individual through policy levels.