Background: Numerous studies have shown that air pollution is a serious public health threat and risk worldwide. Mongolia is the world leader in outdoor and indoor air pollution, and the morbidity and mortality caused by it are increasing every year. People spend most of their lives indoors, and it is necessary to regularly assess and study indoor air pollution. Aim: To study the concentration of PM2.5 particles in the indoor air of households in Ulaanbaatar and Darkhan cities in relation to some symptoms of respiratory diseases. Materials and Methods: The study was conducted using an analytical cohort design from October 2023 to July 2025, and the 4 districts of the central Ulaanbaatar city and Darkhan cities were included in the study. A total of 240 households were included in the study, including 48 households living in ger and house, 24 households living in apartments, and 48 households living in ger and house, and 24 households living in apartments from Ulaanbaatar city. A direct measurement device (PurpleAir) was installed in the households for 3-4 weeks to measure PM2.5 particles in the indoor air for 24 hours. After measuring PM2.5 particles in the indoor air of the household, data were collected through questionnaires from the participants aged 18-60 who participated in the study and underwent health examinations. The results were processed using STATA-19.0 and R programs. Result: 213-239 households were selected for the study, including households living in 17-26 apartments, 42-58 houses, and 38-50 houses. The 24-hour average concentration of PM2.5 particles in the ambient air of households in Ulaanbaatar city was measured relatively higher in winter and summer than in households in Darkhan city. Among the districts of Ulaanbaatar city, the highest concentration of PM2.5 particles was measured in Songinokhairkhan district, and the lowest concentration was measured in Bayanzurkh district. Considering the cities by heating type, households with stoves are more polluted than households with centralized heating. In Darkhan city, the lowest concentration was measured in apartments (22.78-31.53 μg/m³), houses (44.53-68.17 μg/m³), and the highest concentration was measured in traditional felt houses (houses) (63.20-68.25 μg/m³). In Ulaanbaatar, PM2.5 concentrations were relatively high in all types of housing, including apartments (41.61-58.37 μg/m³), houses (79.22-92.50 μg/m³), and traditional felt dwellings (76.69-86.31 μg/m³). In the summer, PM2.5 concentrations in Darkhan were 3.10-10.03 μg/m³ in apartments, 7.67-14.37 μg/m³ in houses, and 7.98-17.90 μg/m³ in traditional felt dwellings (houses). The concentration of PM2.5 particles in the ambient air of the settlement is statistically significantly associated with shortness of breath, fatigue, weakness, muscle pain, nausea, palpitations, sneezing, runny nose, conjunctivitis, pain in the eye socket, tearing of the eyes, headache, fever, nasal congestion, cough, loss of appetite, sore throat, phlegm, wheezing, and chest pain. Conclusion The 24-hour average concentration of PM2.5 particles in indoor air in households in Ulaanbaatar and Darkhan cities is higher than the Mongolian standard during winter and is statistically significantly associated with some symptoms of respiratory diseases.

Background: Ambient and household air pollution remain leading risk factors for global morbidity and mortality. Exposure to fine particulate matter (PM₂.₅) is associated with increased risks of cardiovascular and respiratory diseases, as well as lung cancer, metabolic and neurological disorders, and immune dysfunction. In urban areas of Mongolia, air pollution reaches critical levels during the winter season. Although improved solid fuels have been introduced in recent years, their impact on both outdoor and indoor air quality remains insufficiently characterized. Aim: To compare outdoor and household air pollution levels in Ulaanbaatar and Darkhan cities. Materials and Methods: Outdoor air pollution data for Ulaanbaatar were obtained from fixed monitoring stations of the National Agency for Meteorology and Environmental Monitoring for the period 2014–2026, with seasonal comparisons performed. For indoor air quality assessment, a longitudinal study was conducted among 240 households (apartments, houses, and traditional gers) in Ulaanbaatar and Darkhan from 2023 to 2026. PM₂.₅ concentrations were measured using real-time sensors (PurpleAir sensor), deployed for 14–21 days per season (winter and summer) in each household, recording data at 10-minute intervals over 24-hour periods. Result: Between 2014 and 2026, the 24-hour mean concentrations in Ulaanbaatar were 60.5 µg/m for PM₂.₅, 117.3 µg/m for PM₁₀, 37.3 µg/m for NO₂, 41.8 µg/m for SO₂, and 27.5 µg/m for O₃. While particulate matter levels showed a decreasing trend following the introduction of improved fuels, SO₂ concentrations increased, and overall pollution levels remained higher than those observed in Darkhan. Indoor PM₂.₅ concentrations were higher in Ulaanbaatar compared to Darkhan (60.7±86.1 vs 48.4±96.7 µg/m). Significant differences were observed by housing type (p<0.0001), with higher concentrations in households using solid fuels (houses and gers) and lower levels in apartments. These findings indicate substantial variability in indoor air pollution by city, housing type, and season, with persistently elevated exposure levels. Conclusion Outdoor air pollutant concentrations in Ulaanbaatar, including particulate matter, NO₂, and SO₂, exceed national standards and WHO guideline values by 1–4 times. Indoor PM₂.₅ pollution is higher in Ulaanbaatar than in Darkhan and varies significantly by housing type and season, indicating a high and heterogeneous exposure burden among urban populations.

Background: Respiratory and gastrointestinal infectious diseases are the leading causes of morbidity in children. Numerous international studies have demonstrated that handwashing with soap is one of the most effective and cost-efficient methods for preventing these diseases in children. A previous study conducted in Ulaanbaatar found that only 50.1% of general education school students practiced proper handwashing, which is considered insufficient even in areas with relatively adequate facilities. In Mongolia, 56.1% of the 865 schools lack handwashing facilities and soap, and 25% do not meet the WASH standards. Although knowledge about handwashing increased during the COVID-19 pandemic, sustained behavioral change remained limited, highlighting a gap between knowledge and practice and indicating the need for targeted educational interventions. Furthermore, there is limited research comparing the effectiveness of such interventions across different school environments and urban–rural settings, which provides the rationale for this study. Aim: To evaluate the effectiveness of a handwashing educational intervention among primary school students and determine differences in knowledge change across four schools in urban and rural areas. Materials and Methods: A quasi-experimental study design was used from December 2024 to June 2025. A total of 1,353 students from grades 3–5 in four general education schools (two in Ulaanbaatar and two in rural areas) were included in the study. Preand post-intervention handwashing knowledge scores were analyzed using paired t-tests and one-way ANOVA (α=0.05) with STATA 14.0. Ethical approval was obtained from the Ethics Committee of the Mongolian National University of Medical Sciences. Result: The mean handwashing knowledge score increased significantly from 9.68 (±2.64) before the intervention to 10.30 (±2.74) after the intervention, with a mean difference of +0.63 (p<0.001). The differences in improvement between schools were also statistically significant (ANOVA: F(3,1335)=5.90, p=0.0005). The highest improvement was observed in urban School A (+1.49), while the lowest was observed in School B (+0.16). Rural schools C and D showed moderate and relatively consistent improvements (+0.51 and +0.70, respectively). Conclusion School-based handwashing educational interventions effectively improve knowledge among primary school students. However, environmental factors, such as infrastructure and geographic location, significantly influence the effectiveness of the intervention. Therefore, educational interventions should be implemented alongside infrastructure improvements.

Background: The patients’ view, perception, and evaluation of illness as an individual, as well as their emotional and behavioral responses, are among the criteria predicting the QoL. Increased illness perception and adjustment are emphasized to ensure patients to return to their active life after acute myocardial infarction (AMI) continue their lives more healthily, and have higher levels of physical, mental, and social well-being. Aim: This study aimed to evaluate the illness perception and quality of life of patients who had an AMI. Materials and Methods: This descriptive study included 100 patients diagnosed with AMI at the cardiology department of Third State Central Hospital and Second State Central Hospitals. The data were collected using Illness Perception Questionnaire-Revised and Myocardial Infarction Dimensional Assessment Scale. Result: The mean age of the patients with AMI was 52.2±12.01 years, and 51% were male. Among the subscales of the illness perception questionnaire, the highest mean score was observed for Illness Identity (13.99±5.01), while Treatment Control (19.10±3.18) had the lowest. The lowest score was for Illness Coherence (10.31±2.16). The overall Myocardial Infarction Dimensional Assessment Scale score (43.00±13.10) of the patients was observed to be moderate. The Illness Perception Questionnaire-Revised subdimensions were observed to have a positive and significant correlation with Myocardial Infarction Dimensional Assessment Scale total score and subscales mean scores. Regression analysis revealed that Illness Coherence and Emotional Representation were significant predictors of QOL. Patients scoring high in these areas reported better QOL. Patients with recurrent infarctions showed significantly lower scores in quality of life (t=-2.234, (p=0.029) and illness perception (t=-3.809, p=.001). Conclusion The study demonstrates that illness perception in AMI patients has a significant positive relationship with their quality of life. Specifically, understanding of the illness and emotional representation were key predictors of better quality of life. This suggests that nursing care and psychosocial support targeting patient understanding and emotional coping can play a crucial role in improving post-infarction quality of life.

Background: Bioactive compounds derived from plants have been extensively studied and widely applied in cosmetic and dermatological fields. In particular, plant-derived polyphenols and anthraquinones are known for their antioxidant properties as well as their ability to inhibit elastase enzyme activity. Elastase is a key proteolytic enzyme responsible for degrading elastin, a structural protein essential for maintaining skin elasticity. Excessive elastase activity contributes to skin aging and wrinkle formation. Therefore, the identification of plant-derived compounds capable of interacting with elastase is of significant importance for improving the composition and efficacy of cosmetic products. Aim: To identify bioactive compounds in the extract of Rheum undulatum L. and to investigate their interaction with elastase enzyme activity. Materials and Methods: The root of Rheum undulatum L. was used as the study material. Sample preparation was performed by grinding the plant root followed by extraction using 50% ethanol assisted by an ultrasonic water bath. The obtained extract was evaporated to dryness using a vacuum centrifugation system to remove the solvent completely. A total of 10 mg of the dried extract was dissolved in 100 µL methanol and 900 µL water, then filtered through a 0.1 µm membrane filter. Subsequently, two sample sets were prepared: a control sample and an elastase-incubated sample at a 1:1 ratio. Both were analyzed using liquid chromatography–mass spectrometry (LC-MS). Data processing was performed using Agilent MassHunter Qualitative Analysis software (version 10.0). Results: LC-MS analysis revealed a total of 16 bioactive compounds in the root extract of Rheum undulatum L. Comparative analysis between the control and elastase-treated samples demonstrated a decrease in the peak areas of gluconic acid and citric acid, while an increase in the peak area of emodin was observed. These changes indicate compositional differences between the two sample conditions. Conclusion The LC-MS analysis of Rheum undulatum L. root extract identified multiple bioactive compounds belonging to anthraquinone, phenolic, and flavonoid classes. Variations in peak intensities between control and elastase-treated samples suggest potential interactions between certain compounds and the enzyme. These findings indicate that the root extract contains biologically active constituents capable of modulating elastase activity, supporting its potential application in anti-aging and cosmetic formulations.

Background: Health literacy is a multidimensional concept encompassing the knowledge, attitudes, and skills required for individuals to obtain, understand, appraise, and apply health-related information. It is essential for accessing quality healthcare services and making informed health decisions in daily life. Aim: This study aimed to evaluate the level of health literacy among the adult population of Mongolia. Materials and Methods: A cross-sectional quantitative study was conducted involving 1,500 Mongolian adults. Data was collected using the Health Literacy Survey European Questionnaire (HLS-EU-Q47), which evaluates four core competencies: accessing, understanding, appraising, and applying health information. Responses were measured on a 4-point Likert scale ranging from 1 (very difficult) to 4 (very easy). Health literacy levels were categorized based on standardized scores: inadequate (0–25), limited (25–33), sufficient (33–42), and excellent (42–50). Results: The mean age of the participants was 34.79±15.04 years, with 42.1% being male and 57.9% female. Socioeconomic data showed that 52.1% were married, 37.7% were single, 43.2% had completed secondary education, and 40.5% held a university degree. Lifestyle assessments revealed that 16.4% were daily smokers, 7.0% consumed alcohol daily, and only 12.5% engaged in regular physical exercise. Regarding education, 50.7% of participants with higher education demonstrated “sufficient or excellent” health literacy, whereas only 27.1% of those with secondary education reached this level. The 18–30 age group exhibited the highest capacity to receive health information (44.0%), with a significant decline in health literacy levels observed as age increased (p=0.014). Conclusion Although the overall health literacy level among the adult population of Mongolia is generally sufficient, the capacity to access health information remains limited.

Background: According to the World Health Organization, quality of life is defined as an individual's perception of their position in life within the context of the culture and value systems in which they live, and in relation to their goals, expectations, standards, and concerns. Although numerous epidemiological studies have been conducted worldwide and in Mongolia to investigate the health effects of air pollution, studies examining its impact on the quality of life of the population before and after intervention measures remain limited. Therefore, this study aims to determine the influence of air pollution on the quality of life of residents. Objective: The objective of this study was to assess the quality of life of residents of Chingeltei District, Ulaanbaatar, and to compare their quality of life before and after the implementation of air pollution reduction interventions. Materials and Methods: A total of 330 residents participated in the study, including 165 participants surveyed in 2016 and 165 participants surveyed in 2026. The general characteristics of participants, including age, sex, educational level, marital status, and self-rated health status, were comparable between the 2016 and 2026 surveys. Overall, 47.9% of participants were male and 52.1% were female. In 2016, males accounted for 47.3% and females for 52.7% of the sample. No statistically significant difference was observed in the sex distribution between the two study periods. Results: The mean scores for Domain 1 (Physical Health) and Domain 2 (Psychological Well-being) of quality of life were similar in both survey years, whereas the Social Relationships domain showed improvement. The overall quality of life score increased slightly in 2026 compared with 2016. Furthermore, a one-unit increase in ambient PM₁₀ concentration was associated with an average decrease of 0.123 units in the overall quality of life score. Quality of life was also associated with age, marital status, educational attainment, and self-rated health status. In particular, older individuals and those who perceived their health as poor tended to report lower quality of life scores. These findings indicate that both health-related and socioeconomic factors play important roles in determining quality of life. Conclusion The quality of life of residents of Chingeltei District, Ulaanbaatar, who participated in the study is expected to improve following the implementation of air pollution reduction interventions.
The quality of life of the study participants was found to be at a moderate level and was influenced by factors such as age, marital status, and educational attainment.
Ambient air pollution was found to have a direct impact on the quality of life of the participants. In particular, an increase in PM₁₀ particulate matter concentration was associated with a decline in quality of life.

Background: Air pollution remains a major environmental health risk in Mongolia, particularly in Ulaanbaatar. Although a legal and policy framework for air quality management is in place, evidence on how legislation, institutional arrangements, monitoring systems, and health protection mechanisms function together remains limited. Objective: To assess air pollution levels, evidence of health impacts, and implementation of the legal and regulatory environment for air quality management in Mongolia, and to identify key gaps in comprehensive air quality management from the perspective of protecting children and other vulnerable populations. Materials and Methods: A mixed-methods assessment was conducted in 2023 combining document review, analysis of secondary air quality monitoring data, and qualitative key informant interviews. Historical monitoring data for SO₂, NO₂, PM₁₀, PM₂.₅, CO, and O₃ in Ulaanbaatar for 2008–2017 were analyzed. Relevant laws, policies, standards, and institutional arrangements were reviewed, while qualitative interview data were analyzed thematically. The findings were further contextualized using a targeted evidence update for 2021–2026 and a post hoc secondary analysis based on the five pillars of the 2026 comprehensive air pollution management framework. Results: Air pollution showed a marked seasonal pattern. Mean SO₂ concentrations were 7.57 times higher and NO₂ concentrations 1.66 times higher during the cold season than during the warm season. The 24-hour mean concentration of PM₂.₅ during the cold season was 114.10 µg/m³, while PM₁₀ was 226.77 µg/m³; cold-season PM₂.₅ was 3.9 times higher than in the warm season. Although Mongolia has an established constitutional and sectoral legal basis for air quality management, key informants identified persistent gaps in regulatory enforcement, intersectoral coordination, institutional capacity, human resources, technical capacity, economic incentives, and civil society participation. Monitoring coverage was uneven across pollutants, with limitations in spatial coverage of PM₂.₅ and integration of air quality and health data. The framework-based analysis further identified gaps across rights protection, source-specific regulation, institutional accountability, standards and monitoring, and implementation programmes. Conclusion The principal challenge for air quality governance in Mongolia is not the absence of legislation, but the gap between legal and policy provisions and their effective implementation and measurable health outcomes. Strengthening a child-centred, source-based and multisectoral air quality management system that integrates institutional accountability, monitoring, health surveillance, financing, and enforcement is warranted.

Introduction: Arsenic is a widespread environmental metalloid that poses a global health risk, particularly through contamination of drinking water. Exposure arises from natural and human activities through ingestion, inhalation, and skin absorption. Its absorption and toxicity vary by chemical form, with trivalent arsenic generally more toxic than pentavalent arsenic. Once absorbed, arsenic can accumulate in tissues and body fluids. Objective: To compare urinary arsenic concentrations among adults residing in selected mining and non-mining areas of Mongolia. Materials and Methods: This cross-sectional study included 422 adults from mining areas (n = 333; Bayan-Undur, Tsogtsetsii, and Khanbogd) and non-mining areas (n = 89; Bulgan and Bayandalai). Questionnaire data on sociodemographic characteristics, occupation, smoking, and dietary habits were collected. Urine samples were analyzed using inductively coupled plasma mass spectrometry. Arsenic concentrations were summarized as geometric means (GMs) with 95% confidence intervals (CIs). Results: Of the 422 participants, 242 (57.3%) were women. The GM urinary arsenic concentration was 31.10 µg/L [95% CI, 28.96–33.58] in mining areas and 26.42 µg/L [95% CI, 22.98–30.39] in non-mining areas. Among mining communities, GMs were 33.45 µg/L in Bayan-Undur, 25.49 µg/L in Tsogtsetsii, and 24.82 µg/L in Khanbogd. In the non-mining communities, GMs were 29.43 µg/L in Bulgan and 23.02 µg/L in Bayandalai. Conclusion The urinary arsenic concentration was higher among adults in the selected mining areas, with variation between communities. Further analyses accounting for potential confounders, together with arsenic speciation and environmental measurements, are needed to clarify exposure sources and the contribution of mining activities.

Background: Indoor air quality in schools is an important environmental health concern because children spend a substantial proportion of their time in classrooms and are particularly vulnerable to air pollutants. Objective: To assess common chemical, and biological pollutants in the indoor air of general education schools in Ulaanbaatar. Methods: A cross-sectional study was conducted from October 10, 2025, to March 1, 2026, in 16 purposively selected schools and 32 classrooms across six districts of Ulaanbaatar. PM2.5, PM10, CO₂, and microclimatic parameters were monitored continuously for seven days. Volatile organic compounds, formaldehyde, BTEX compounds, and radon were also measured. Airborne microorganisms were assessed using 160 air samples, and 160 surface swabs were collected. Results were compared with MNS 7106:2026, MNS 5484:2005, and MNS 6410:2018 standards. Results: The mean 24-hour concentrations of PM2.5 and PM10 were 25.2 and 36.1 µg/m³, respectively. PM2.5 exceeded the permissible level during winter and in schools located in apartment areas, whereas the mean PM10 concentration met the acceptable level. Total bacteria were detected in all air samples, with a mean concentration of 1,733.25 CFU/m³. Mould and fungi were detected in 56.3% of classrooms, and enteric bacteria were detected in 4.3% of surface swabs. Radon levels remained below the permissible limit, and pathogenic bacteria were not detected. Formaldehyde was detected in all samples, while total VOCs and toluene were detected in 81.3%; their mean concentrations remained within acceptable levels. In one classroom, the concentration of benzene was detected approximately 30 times higher the permissible level. Conclusion Although some indoor air-quality indicators met the relevant standards, PM2.5, total bacteria, mould and fungi, surface enteric bacteria, and benzene contamination require improvement and may pose health risks to children. Regular ventilation, improved cleaning and hygiene, proper maintenance of HEPA devices, and routine monitoring of particulate matter, mould, and VOCs are needed.