Enhancing indoor air quality: Harnessing architectural elements, natural ventilation and passive design strategies for effective pollution reduction - A comprehensive review.

Air pollution poses a critical global challenge with severe environmental and human health implications. The associated health risks, including premature mortality, underscore the urgency of effective mitigation strategies. Many studies focus on control strategies without considering specific contaminant types, and there is a notable gap in research on cost-effective, eco-friendly methods, especially in countries facing substantial air pollution challenges. This study aims to fill this gap by providing a comprehensive review of various air pollutants and proposing optimal passive design strategies for mitigating them in building facades. Through a structural process and comparative analysis of existing literature, this study evaluates the cost, maintenance, applicability of retrofitting, and removal efficacy of three categories of control strategies: bio-filtration, adsorbents, and water-based approaches. The results confirm that biological air purification systems are more effective than other methods at reducing PM2.5, PM10, and VOCs. Moreover, the cost analysis confirms that the more costly approaches are photocatalytic filters and metal-organic frameworks derived from the adsorbent solutions. Thus, the study suggests applying cost-effective techniques like facade biofiltration, and water-based curtain façade in areas with high air pollution. In terms of the applicability of retrofitting, the results ascertain adsorbent strategies are the most effective for reducing air pollutants in existing buildings followed by water-based methods. Considering limitations associated with certain strategies, such as the high cost and regular maintenance, this study proposes five integrated strategies for the effective control and removal of pollutants from building exteriors. By addressing these gaps in knowledge and offering practical insights, this research contributes valuable guidance for architects, policymakers, and practitioners in developing sustainable, efficient solutions to combat indoor air pollution effectively.

Exposure to mixture particulate contaminants in the air and the risk of oral cancer: An updated systematic review and meta-analysis.

The mixture of contaminants in the air (e.g., PM2.5, smoke) is a part of air pollutants that has become a hot environmental issue. Previous epidemiological studies have reported the relationship between wood smoke and PM2.5 exposure and oral cancer, but findings have been inconsistent. Therefore, this work designed to find out the relationship between mixture contaminants in air exposure and oral cancer. Fourteen studies were included through research in three databases before February 2024. Before analysis, the Newcastle-Ottawa Scale was applied to examine the quality of all selected studies. Then, the meta-analysis was carried out by meta-regression analysis, sensitivity analysis and subgroup analysis. The results showed that exposure to PM2.5 may have a positive association with oral cancer (pooled OR = 1.13, 95 % confidence interval: 1.06, 1.20). In contrast, no significant association was found between indoor air pollution and oral cancer. However, the result of the subgroup analysis indicated there is a significant association of indoor air pollution and oral cancer in developing countries (pooled OR = 2.5, 95 % confidence interval: 1.7, 3.6). In addition, the heterogeneity among studies of indoor air pollution exposure and oral cancer may caused by studies carried out in developed countries according to the subgroup and meta-regression analyses. In conclusion, the studies about indoor air pollution exposure and oral cancer are discrepant. The effects of mixed air contaminants for people's health are not simple and more studies are demanded to find out it in the future.

Effects of household solid fuel use on sarcopenia in middle-aged and older adults: evidence from a nationwide cohort study.

Background: Household solid fuel use is common in global households and has been linked to changes in handgrip strength and muscle mass. However, whether household solid fuel use results in sarcopenia over time is not well elaborated. Methods: This study employed data from the 2011-2015 China Health and Retirement Longitudinal Study (CHARLS) that recruited 4,932 participants ≥45 years. The Cox proportional hazards regression model was conducted to estimate the impact of household solid fuel use for cooking and heating on sarcopenia development. The analysis was further stratified based on geographic position. Mediation analysis was employed to estimate the potential mediating effects of cognitive function and depressive symptoms associated with household solid fuel use and sarcopenia. Results: Over the 4-year follow-up, 476 cases of sarcopenia were reported (9.65%), with 254 in males (10.82%) and 222 in females (8.59%). Cooking and heating with solid fuels increased the risk of sarcopenia (Cooking: HR 1.401, 95% CI 1.138-1.724; Heating: HR 1.278, 95% CI 1.040-1.571). Crop residue/wood burning correlated with higher sarcopenia risk (Cooking: 1.420, 95% CI 1.147-1.758; Heating: 1.318, 95% CI 1.062-1.635). Switching to clean cooking fuels significantly reduced sarcopenia risk (HR 0.766, 95% CI 0.599-0.979). Heating with solid fuels was associated with higher sarcopenia risk only in southern China (HR 1.375, 95% CI 1.102-1.715). Additionally, cognitive function and depressive symptoms partially mediated the link between household solid fuel use and sarcopenia. Conclusion: Household use of solid fuels is associated with an increased risk of sarcopenia. Restricting the use of solid fuels and focusing on cognitive function and depressive symptoms in solid fuel users can help decrease sarcopenia development.

Association between window ventilation frequency and depressive symptoms among older Chinese adults.

OBJECTIVES: Indoor air pollution exposure is harmful to people's physical and mental health, especially in the elderly population. Depressive symptoms are the most common mental health issue among elderly individuals. However, evidence linking the frequency of indoor natural ventilation to depressive symptoms in the elderly population is limited. METHODS: This study included 7887 individuals 65 years and older from 2017 to 2018 the China Longitudinal Healthy Longevity Survey (CLHLS). The frequency of indoor window ventilation was measured as the self-reported times of ventilation of indoor window per week in each season, and the four seasons' scores were added up to calculate the annual ventilation frequency. Depressive symptoms were measured by the 10-item Center for Epidemiologic Studies Short Depression Scale (CESD). Using three models adjusted for demographic, socio-economic, health status, and environmental factors successively, the correlation between indoor window ventilation frequency and depressive symptoms was verified through logistic regression. RESULTS: Among the 7887 elderly people included in this study, 1952 (24.7 %) had depressive symptoms. In the fully adjusted model, compared with the lower indoor annual ventilation frequency group, high indoor annual ventilation frequency group was significantly associated with a 33 % (OR: 0.67, 95%CI: 0.51-0.88) lower probability of depressive symptoms. Subgroup analysis and sensitivity analysis yielded similar results. CONCLUSIONS: High frequency of window ventilation is significantly associated with the lower risk of depressive symptoms in Chinese individuals aged 65 and older. This result provides strong evidence for health intervention and policy formulation.

A review of recent advances in metal-organic frameworks materials for zero-energy passive adsorption of chemical pollutants in indoor environments.

Approximately 75-90 % of a person's lifetime is spent inside increasingly airtight buildings, where indoor pollutant levels typically exceed those outdoors. Poor indoor air quality can lead to allergies, respiratory diseases, and even cancer, and can also reduce the longevity of buildings. Passive adsorption materials play a crucial role in reducing indoor pollutants. This review highlights the latest advances in using Metal-organic Frameworks (MOFs) as passive adsorption materials for indoor pollutant capture and outlines the principles for developing high-performance adsorbents. It provides a comparative analysis of the development and performance of MOFs and composite adsorbent materials, highlighting their respective advantages and limitations in indoor pollutant adsorption technology. The article proposes strategies to address these challenges and offers a comprehensive review of current practical adsorption devices. Finally, aiming to advance commercialization of MOFs, the anticipated development of indoor pollutant adsorption technology is discussed in this paper.

Indoor air pollution impacts cardiovascular autonomic control during sleep and the inflammatory profile.

The present study explores the modifications of cardiovascular autonomic control (CAC) during wake and sleep time and the systemic inflammatory profile associated with exposure to indoor air pollution (IAP) in a cohort of healthy subjects. Twenty healthy volunteers were enrolled. Indoor levels of fine particulate matter (PM2.5), nitrogen dioxide (NO2) and volatile organic compounds (VOCs) were monitored using a portable detector for 7 days. Together, a 7-day monitoring was performed through a wireless patch that continuously recorded electrocardiogram, respiratory activity and actigraphy. Indexes of CAC during wake and sleep time were derived from the biosignals: heart rate and low-frequency to high-frequency ratio (LF/HF), index of sympathovagal balance with higher values corresponding to a predominance of the sympathetic branch. Cyclic variation of heart rate index (CVHRI events/hour) during sleep, a proxy for the evaluation of sleep apnea, was assessed for each night. After the monitoring, blood samples were collected to assess the inflammatory profile. Regression and correlation analyses were performed. A positive association between VOC exposure and the CVHRI (Δ% = +0.2% for 1 µg/m3 VOCs, p = 0.008) was found. The CVHRI was also positively associated with LF/HF during sleep, thus higher CVHRI values corresponded to a shift of the sympathovagal balance towards a sympathetic predominance (r = 0.52; p = 0.018). NO2 exposure was positively associated with both the pro-inflammatory biomarker TREM-1 and the anti-inflammatory biomarker IL-10 (Δ% = +1.2% and Δ% = +2.4%, for 1 µg/m3 NO2; p = 0.005 and p = 0.022, respectively). The study highlights a possible causal relationship between IAP exposure and higher risk of sleep apnea events, associated with impaired CAC during sleep, and a pro-inflammatory state counterbalanced by an increased anti-inflammatory response in healthy subjects. This process may be disrupted in vulnerable populations, leading to a harmful chronic pro-inflammatory profile. Thus, IAP may emerge as a critical and often neglected risk factor for the public health that can be addressed through targeted preventive interventions.

A novel approach for large-scale characterization of residential cooking-generated PM with computer vision and low-cost sensors.

Cooking is one of the major sources of indoor particulate matter (PM), which poses significant health risks and is a severe health hazard. Current studies lack an economical and effective analytical framework for quantifying inhalable particles (PM10) and fine particulate matter (PM2.5) from residential cooking activities on a large scale under real-world scenarios. This study bridges this gap by employing computer vision (CV) technology and readily available sensors. We collected data over a month in real-world settings, including cooking videos and air quality data (indoor PM10, PM2.5, CO2, temperature, relative humidity, and outdoor PM10 and PM2.5 concentrations). To classify high-emission (pan-frying, stir-frying, deep-frying) and low-emission (stewing, steaming, boiling, non-cooking) activities, we developed and validated a robust CV model named "Cooking-I3D." This model leverages a pre-trained Two-Stream Inflated 3D ConvNet (I3D) architecture. We then assessed the efficacy of the CV-predicted cooking method in PM characterization using a first-order multivariate autoregressive model, controlling for environmental factors. The Cooking-I3D model achieved exceptional performance, boasting an accuracy of 95 % and an Area Under the Curve (AUC) of 0.98. Our results indicate that a single 6-minute high-emission cooking event triggers a 21-25 % increase in indoor PM concentrations and a 23-24 % increase in the indoor/outdoor ratio, with relative errors in these estimates ranging from 10 to 21 %. This innovative method offers a powerful tool for long-term assessment of cooking-related indoor air pollution and facilitates precision exposure assessment in human health studies.

A model of the spatiotemporal distribution of ozone-squalene reaction and ozonolysis by-products from human body.

Emissions of ozone and its by-products from ozonolysis on human surfaces lead to indoor air pollution. However, the spatiotemporal distribution of such emissions in indoor environments remains unclear, which may introduce bias when assessing human exposure to ozone and ozonolysis byproducts. This study developed a computational fluid dynamics model to describe the physical and chemical processes involved in the emission of ozone-dependent volatile organic compounds from the human body. The results showed that the reaction probability of ozone in the human body depends on the ozone concentration in the bulk air. For ozone concentrations ranging from 28 ppb to 200 ppb, the reaction probabilities ranged from 5.9 × 10-5 to 1.5 × 10-4. The concentrations of ozone and ozonolysis byproducts obtained from the experimental measurements were used for model validation. The ozonolysis by-products were found to be uniformly distributed in the chamber, whereas the ozone distribution showed less uniformity. The ozone concentration near the human surface was approximately 30 %∼50 % of that in the ambient air. Overall, a model was developed to understand the effect of ozone-surface interactions on indoor air quality. This model can be applied to analyze human exposure to ozone and ozonolysis byproducts and for health risk assessment in built environments.

Indoor air pollution and airway health.

Because of the disproportionate amount of time that people spend indoors and the complexities of air pollutant exposures found there, indoor air pollution is a growing concern for airway health. Both infiltration of outdoor air pollution into the indoor space and indoor sources (such as smoke from tobacco products, cooking or heating practices and combustion of associated fuels, and household materials) contribute to unique exposure mixtures. Although there is substantial literature on the chemistry of indoor air pollution, research focused on health effects is only beginning to emerge and remains an important area of need to protect public health. We provide a review of emerging literature spanning the past 3 years and relating indoor air exposures to airway health, with a specific focus on the impact of either individual pollutant exposures or common combustion sources on the lower airways. Factors defining susceptibility and/or vulnerability are reviewed with consideration for priority populations and modifiable risk factors that may be targeted to advance health equity.

Assessment of Indoor Particulate Matter and Teacher's Perceived Indoor Climate in Government Schools of Bilaspur District, Chhattisgarh, India: A Cross-Sectional Study.

Context: Indoor air pollution (IAP) affects the long-term health, cognitive growth, and academic performance of children. Since children spend most of their time at school, quantifying IAP in classrooms is an important parameter for air pollution. Aim: To assess the average particulate matter (PM) levels inside and outside of classrooms along with their associated factors and teacher's perceived indoor climate. Setting and Design: Cross-sectional survey in nine government-run schools. Methods and Material: PM2.5 and PM10 were measured inside the classroom and outdoors simultaneously during summers, using an Atmos monitor for two consecutive days, along with several school and classroom characteristics. Perception about indoor air quality was captured from teachers (n = 15) using a validated questionnaire. Statistical Analysis: Mean values of PM using mixed effect linear regression. Perceived indoor air quality is presented using percentages. Results: Mean indoor PM2.5 and PM10 was 52.5 µg/m3 and 65 µg/m3. Indoor and outdoor PM levels were highly correlated, but the indoor-outdoor ratio of PM concentrations was more than 1. Teachers were mostly bothered by dust, dirt, and noise in the schools. Conclusion: Indoor air quality was higher than World Health Organization (WHO) standards but within the national standards. Need further research to find the exact cause for higher indoor PM levels compared to outdoor PM levels.

Effects of indoor environments and outdoor air pollutants in residential areas on acute exacerbation in patients with severe asthma.

This study aimed to determine the effects of indoor environment (IE) and outdoor air pollutants (OAPs) in residential areas on acute exacerbation (AE) in patients with severe asthma. A total of 115 participants were recruited. To characterize IE, we used structured questionnaires and estimated OAP concentrations using a land-use regression model. Participants who were exposed to passive smoking and lived in houses where the kitchen and living room were not separated showed a significantly higher rate of AE (p = 0.014 and 0.0016, respectively). The mean concentration of PM2.5 in residential areas during the last 3 years was significantly higher in participants with AE than that in those without AE (19.8 ± 3.1 vs. 21.0 ± 2.5 µg/m3, p = 0.033). Moreover, the serum level of 8-hydroxy-2'-deoxyguanosine significantly increased in participants with AE compared to those without AE (56.9 ± 30.0 vs. 94.7 ± 44.5 ng/mL, p = 0.0047) suggesting enhanced oxidative stress in those with AE.

Investigating exceedances of formaldehyde levels and source identification in offices of an academic medical institute.

OBJECTIVES: To investigate factors associated with indoor formaldehyde levels in office settings within an academic medical institute. METHODS: This cross-sectional study was conducted in 25 offices (261 workers) at a medical university in Thailand. Questionnaires gathered data on demographics, work patterns, and office equipment usage (printers, photocopiers, air fresheners, liquid paper, glue, cleaning agents, and marker pens). The building environment was assessed by a multidisciplinary team. Formaldehyde levels and relevant parameters (temperature and relative humidity) were measured in each room both indoors and outdoors. A multiple linear regression model investigated the relationship between formaldehyde and office factors, controlling for room conditions. RESULTS: Median office formaldehyde levels were 442.1 µg/m3 (interquartile range: 343.8-908.7 µg/m3), exceeding World Health Organization and Thai guidelines. Photocopier use was significantly associated with higher levels of indoor formaldehyde (ß = .20; 95% CI, 0.30-0.37; P = .02). Air freshener use also showed a significant association (ß = .56; 95% CI, 0.30-0.81; P < .001). No correlation was found between the use of liquid paper, glue, printers, cleaning agents, or marker pens and indoor formaldehyde levels. CONCLUSIONS: Indoor formaldehyde levels in these offices exceeded the established guidelines. Use of photocopiers and air fresheners was associated with increased formaldehyde levels. Implementing interventions such as improved ventilation and regular screening is essential for creating healthier office environments.

Association between exposure to smoke from cooking fuels and anaemia among women of reproductive age in Ghana.

In low- and middle-income countries, indoor air pollution (IAP) is a serious public health concern, especially for women and children who cook with solid fuels. IAP exposure has been linked to a number of medical conditions, including pneumonia, ischemic heart disease, stroke, chronic obstructive pulmonary disease (COPD), lung cancer, and anaemia. Around 500 million women of reproductive age (WRA) suffer from anaemia globally, with an estimated 190 million cases in sub-Saharan Africa (SSA). This study, which is based on prior research, investigates the relationship between IAP exposure and anaemia among WRA in Ghana. A diverse sample of 2,406 WRA living in Ghana were interviewed, of which 58.06% were anaemic and used high-pollutant fuels for cooking. Age, place of residence, region, education level, religion, ethnicity, wealth index, type of drinking water, type of toilet facility, and type of cooking fuels were all found to be significantly linked with anaemic state by bivariate analysis. Type of cooking fuels utilized, age, region of residence, and the type of residence were shown to be significant predictors of anaemia status using sequential binary logit regression models. The results emphasise the critical need for efforts to promote the usage of clean cooking fuel in an attempt to lower anaemia prevalence in Ghana. To reduce dependency on solid fuels for cooking, initiatives should promote the use of cleaner cooking fuels and enhance the socioeconomic status of households. These interventions could have significant public health effects by reducing the burden of anaemia and improving maternal and child health outcomes due to the prevalence of anaemia among WRA. Overall, this study sheds light on the relationship between IAP exposure and anaemia in Ghana and highlights the demand for focused public health initiatives to address this serious health problem.

Associations between fine particulate matter, gene expression, and promoter methylation in human bronchial epithelial cells exposed within a classroom under air-liquid interface.

Associations between indoor air pollution from fine particulate matter (PM with aerodynamic diameter dp < 2.5 µm) and human health are poorly understood. Here, we analyse the concentration-response curves for fine and ultrafine PM, the gene expression, and the methylation patterns in human bronchial epithelial cells (BEAS-2B) exposed at the air-liquid interface (ALI) within a classroom in downtown Rome. Our results document the upregulation of aryl hydrocarbon receptor (AhR) and genes associated with xenobiotic metabolism (CYP1A1 and CYP1B1) in response to single exposure of cells to fresh urban aerosols at low fine PM mass concentrations within the classroom. This is evidenced by concentrations of ultrafine particles (UFPs, dp < 0.1 µm), polycyclic aromatic hydrocarbons (PAH), and ratios of black carbon (BC) to organic aerosol (OA). Additionally, an interleukin 18 (IL-18) down-regulation was found during periods of high human occupancy. Despite the observed gene expression dysregulation, no changes were detected in the methylation levels of the promoter regions of these genes, indicating that the altered gene expression is not linked to changes in DNA methylation and suggesting the involvement of another epigenetic mechanism in the gene regulation. Gene expression changes at low exposure doses have been previously reported. Here, we add the possibility that lung epithelial cells, when singly exposed to real environmental concentrations of fine PM that translate into ultra-low doses of treatment, may undergo epigenetic alteration in the expression of genes related to xenobiotic metabolism. Our findings provide a perspective for future indoor air quality regulations. We underscore the potential role of indoor UFPs as carriers of toxic molecules with low-pressure weather conditions, when rainfall and strong winds may favour low levels of fine PM.

Association of anaemia with indoor air pollution among older Indian adult population: multilevel modelling analysis of nationally representative cross-sectional study.

INTRODUCTION: Anaemia is a disease of public health importance with multi-causal pathways. Previous literature suggests the role of indoor air pollution (IAP) on haemoglobin levels, but this has been studied less due to logistic constraints. A high proportion of the population in developing countries, including India, still depends on unclean fuel, which exacerbates IAP. The objective was to study the association between anaemia and IAP among the older Indian adult population (≥ 45 years) as per gender. METHODS: Our study analysed the nationally representative dataset of the Longitudinal Ageing Study in India (LASI 2017-18, Wave-1). We have documented the association of anaemia (outcome variable) with IAP (explanatory variable). To reduce the confounding effects of demographic and socioeconomic; health related and behavioural covariates; propensity score matching (PSM) was conducted. Nested multilevel regression modelling was conducted. States and union territories were categorised cross tabulated as low, middle and high as per anaemia and IAP exposure. P value < 0.05 was considered statistically significant. SATA version 17 was used for analysis. RESULTS: More than half (52.52%) of the participants were exposed to IAP (male (53.55%) > female (51.63%)). The odds of having anaemia was significantly 1.19 times higher (AOR 1.19 (1.09-1.31)) among participants using unclean/ solid fuel. The adjusted odds were significantly higher among participants exposed to pollution-generating sources (AOR 1.30; 1.18-1.43), and household indoor smoking (AOR 1.17 (1.07-1.29). The odds of having anaemia were significantly higher (AOR 1.26; 1.15-1.38) among participants exposed to IAP, which was higher in males (AOR 1.36; 1.15-1.61) than females (AOR 1.21; 1.08-1.35). Empowered Action Group (EAG) states like Uttar Pradesh, Chhattisgarh, Madhya Pradesh, Bihar had both high anaemia and IAP exposure. CONCLUSION: This study established the positive association of anaemia with indoor air pollution among older Indian adults through a nationally representative large dataset. The association was higher among men. Further research is recommended to understand detailed causation and to establish temporality. It is a high time to implement positive intervention nationally to decrease solid/ unclean fuel usage, vulnerable ventilation, indoor smoking, IAP and health hazards associated with these with more focused actions towards EAG states.

A Comprehensive Literature Review on the Effects of Formaldehyde on the Upper Respiratory Tract.

Prolonged exposure to indoor air pollutants at high concentrations can have adverse health effects on the respiratory system of individuals who spend most of their time indoors. Formaldehyde (FA) is a common indoor air pollutant because of its extensive use in household products such as cleaners, floorings, and furnishings. As a chemical, FA is highly water soluble and reactive. When its airborne form is inhaled, it is mainly absorbed in the upper airways. FA has been extensively studied for its carcinogenic effects, but it can also cause inflammation in the upper airways. The objective of the current review was to assess the secondary effects of such inflammation and how it can contribute to an increased risk for upper respiratory infections, which are mostly caused by viruses. A rigorous literature review was conducted through gathering, reading, and analyzing relevant literature, including peer-reviewed articles published after 1990 and seminal literature regardless of publication date. Findings from the review provide a greater understanding of the outcomes of FA exposure, the potential accumulative damage to the upper respiratory tract, and the associated increased risk for acute infections of the upper respiratory tract. This information can help in the development and enforcement of stricter regulations for furniture and building materials for household-related products to limit exposure to indoor pollutants such as FA.

Association of Exposure to Indoor Air Pollution with Unhealthy Symptoms among Middle-aged and Older Adults in India: Evidence from a Large-scale Survey.

Background: The usage of solid cooking fuels is widely prevalent in low and middle-income countries, including India, and contributes to indoor air pollution (IAP), which has detrimental health effects. Moreover, time spent inside the house increases as people age. In this context, the present study tried to understand the association between exposure to indoor air pollution and unhealthy symptoms, including shortness of breath, dizziness, headache, fatigue, wheezing, and cough among middle-aged and older adults in India. Methods: We extracted the unit-level individual data (N = 63 790) from the Longitudinal Aging Study in India (LASI)-Wave 1 (2017-2018). The statistical analyses used were Chi-square test and binary logistic regression, which estimated the odds ratio to identify the determinants of the unhealthy symptoms. Results: The odds of shortness of breath (adjusted OR: 1.14, 99% CI: 1.05-1.23), dizziness (adjusted OR: 1.28, 99% CI: 1.21-1.35), fatigue (adjusted OR: 1.32, 99% CI: 1.26-1.39), wheezing (adjusted OR: 1.30, 99% CI: 1.19-1.42), and cough (adjusted OR: 1.36, 99% CI: 1.27-1.45) were higher among individuals from households where solid cooking fuels was used. Similarly, the odds of shortness of breath, headache, wheezing, and cough were higher among individuals with a household member who smoked inside the house. The results indicated that the odds of shortness of breath, headache, and cough were significantly lower among participants exposed to incense use. Conclusion: Based on the results of this study, we suggest developing programs to combat the sources of indoor air pollution and the associated unhealthy symptoms, especially in rural settings. It is also important to bring awareness and practice clean fuel usage at individual and community levels to improve population health.

This study is the first of its kind to explore indoor air pollution and unhealthy symptoms among a large sample in India. We believe it will contribute significantly to the global literature on indoor pollution and health outcomes.

Assessing the health consequences of indoor air pollution from biomass fuel combustion on pediatric populations in rural communities of Pakistan.

Indoor air pollution arising from burning of biomass fuels poses a significant threat to child health in rural areas of Pakistan. This cross-sectional study aimed to assess health implications associated with indoor air pollution resulting from biomass burning among children under 12 years of age in rural Punjab. A questionnaire-based survey was conducted in six randomly selected rural districts of Punjab, characterized by their primary reliance on biomass fuels. The findings revealed that several characteristics, such as monthly household income, number of living rooms, secondary use of solid fuels, kitchen type, type of cooking stove, and presence of child in the kitchen with their mother, exhibited significant associations (p < 0.05) with negative health impacts among children. Reported health effects among the children included coughing (18.7%), watery eyes (17.7%), eye irritation (12.3%), runny nose (11.8%), breathing difficulties (8.5%), phlegm (38%), headache (25%), nausea (20.1%), dizziness (6.7%), asthma (6.4%), tuberculosis (1.8%), and pneumonia (1.5%).

Phytoremediation of formaldehyde by three selected non-native indoor plant species.

Formaldehyde 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.

Association between early-life mosquito repellents exposure and ADHD-like behaviours.

BACKGROUND: Limited research has explored the impact of mosquito repellents exposure during early life on ADHD symptoms. This study aimed to explore the associations of exposure to mosquito repellents from pregnancy to 3 years old and the prevalence of ADHD-like behaviours among children aged 3-9 years, and further identify the sensitive exposure period. METHODS: A cross-sectional study was conducted, including 12 275 children in Hefei City, China. Exposure was self-reported via primary caregivers. ADHD-like behaviours were measured by the Swanson, Nolan and Pelham, version IV scale (SNAP-IV), and Conners' Parent Rating Scale (CPRS). Cross-over analysis, binary logistic regression and linear regression were employed. RESULTS: After adjusting for confounding variables, early-life exposure to mosquito repellents was associated with a higher risk of ADHD-like behaviours (OR = 1.81, 95% CI = 1.49-2.19). By comparing the strength of the association for each subgroup, we found exposure during 1-3 years old was a sensitive period (OR = 1.89, 95% CI = 1.25-2.87) by the cross-over analysis. Furthermore, we found a dose-response relationship in which the likelihood of ADHD-like behaviours increased with children's early-life mosquito repellents exposure dose. CONCLUSIONS: Early-life exposure to mosquito repellents is linked with an elevated risk of ADHD-like behaviours in children, with a sensitive period identified during 1-3 years old.