Background: Radon is a naturally occurring radioactive gas produced from the decay of uranium found in rocks and soil. It is released into the air and can accumulate in enclosed spaces, entering the human body through the respiratory system [1]. Most households in ger districts live in small dwellings with earthen foundations, poor ventilation, and tightly sealed structures designed to retain heat, creating conditions for elevated indoor radon levels [2]. This gas is colorless, odorless, and tasteless, making it difficult to detect, and it tends to accumulate indoors, especially in poorly ventilated spaces. High indoor radon levels can damage lung tissue and alter DNA structure, thereby increasing the risk of cancer development [3]. According to the World Health Organization, radon is responsible for approximately 3–14% of lung cancer cases worldwide and is considered the second leading cause of lung cancer after smoking [4]. The permissible indoor radon concentration has been established at 200 Bq/m³ for existing buildings and 100 Bq/m³ for newly constructed buildings [5].
The World Health Organization has warned that the combined effects of outdoor and household air pollution contribute to approximately 6.7 million premature deaths annually [6]. In Mongolia, studies in this field remain limited, which served as the basis for conducting the present research. Objective: To assess indoor radon concentration and selected microclimate indicators in households of Khoroo 15, Chingeltei District, and compare them with hygienic standards. Materials and Methods: A descriptive cross-sectional study design was used. From a total of 2,125 households in the ger district of Khoroo 15, Chingeltei District, a sample size of 71 households was determined using the OpenEpi statistical program. Indoor radon concentration was measured in each household for 48 hours using a “Wave Radon” electronic device. Data were entered into Word and MS Excel, then analyzed using SPSS version 27. Descriptive statistics (mean, frequency, minimum, maximum, standard deviation) were calculated, and differences between variables were assessed using the chi-square test. Results: The average indoor radon concentration was 173.2 Bq/m³, with a maximum of 596 Bq/m³ and a minimum of 26 Bq/m³. A total of 31% (22 households) exceeded the hygienic standard (>200 Bq/m³). Radon concentration was higher in houses (246.05 Bq/m³; min=48, max=596) compared to gers (94 Bq/m³; min=26, max=325). Indoor radon concentration showed a moderate inverse correlation with outdoor temperature (p=0.003, r=-0.346) and a moderate positive correlation with indoor humidity (p=0.001, r=0.513).
The average age of houses was 23 years (range: 1–48 years), and radon concentration was not associated with building age (r=0.035, p=0.838). When categorized by building material, the highest mean radon concentration was found in brick houses (307 Bq/m³), followed by concrete houses (271.4 Bq/m³) and wooden houses (206.6 Bq/m³), while the lowest was in traditional gers (93.8 Bq/m³). However, these differences were not statistically significant (p=0.208). Conclusion
1. The study on radon concentration in household indoor air revealed that, among households living in houses and apartments, some cases exceeded the hygienic standard limits. The research results indicate that the indoor radon concentration in ger district households is associated with ambient temperature and indoor humidity levels.
2. It was also determined that radon concentration varies depending on factors such as housing structure, building materials, and stove type. Among the types of dwellings included in the study, brick and concrete buildings showed relatively higher radon concentrations, whereas traditional Mongolian gers had the lowest levels

Introduction: According to the World Health Organization (WHO) data from 2022, 19.9 million people were diagnosed with cancer globally, and 9.7 million people died from the disease. In recent years, the incidence of colorectal cancer (CRC) has been rapidly increasing, ranking 4th among all cancers with 18.4 cases and 8.1 deaths per 100,000 population. In Mongolia, 826 new cases of CRC have been registered over the past six years, with an incidence rate of 8.2 cases and a mortality rate of 5.03 per 100,000 population. It is projected that by 2030, the incidence will reach 13.28 cases and the mortality rate will rise to 8.72 per 100,000 population. We aimed to comprehensively examine the risk factors for colorectal cancer among the population of Mongolia, establish a scientific basis for early detection and prevention, and strengthen preventive measures. Materials and Methods: A case-control study was conducted from 2022 to 2024. The study enrolled a total of 305 subjects, including 98 patients with colorectal cancer, 101 patients with colon polyps, and 106 healthy subjects. The risk. questionnaire consisted of 50 questions divided into 10 sections. All statistical analysis was performed with SPSS version 23.0 software (SPSS Inc., Chicago, IL, USA) and P value <0.05 was considered statistically significant. categorical data was represented as numbers and percentages. Pearson’s chi-squared and Fisher’s exact test were used to compare categorical variables. Multivariate logistic regression was used to identify the risk factor associated with recurrence. The study protocol was approved by Ethics Review Committee of Ministry of Health of Mongolia on 17 March 2023 (approval number: 23/012). Results: The average age of the participants was 57.1±12.8 years. Among all study participants, 37.6% (115) were male and 62.4% (188) were female. Comparison of colorectal cancer incidence by age and gender revealed no statistically significant differences (p=0.021; p=0.422). Regular physical exercise was found to have a protective effect against colorectal cancer (p=0.076; OR 0.341 95% Cl 0.118-.0986). The frequency of fruit consumption, 4 to 6 times per week (p=0.008, OR 0.08, 95% Cl 0.01-0.45), frequency of vegetable consumption 4 to 6 times per week (p<0.00; OR 0.07, 95% Cl 0.02-0.19), no dining out (0.007, OR 0.3, 95% Cl 0.18-0.68), and meat consumption (p=0.001) are decreased risk of colorectal cancer. Conclusion The patient's age and the presence of colon polyps are risk factors for colorectal cancer, while regular physical activity and a diet rich in fruits and vegetables are protective factors that help reduce the risk of developing colorectal cancer.

Background: Demyelinating disorders are a group of chronic immune-mediated diseases affecting myelinated axons in the central nervous system, which lead to life-long disability. In Mongolia, the last regional prevalence study was conducted in 2010. Our study objective is to describe the current prevalence of multiple sclerosis (MS) and other demyelinating disorders in Mongolia. : Aim Materials and Methods: We registered MS, neuromyelitis optica spectrum disease (NMOSD), myelin oligodendrocyte glycoprotein (MOG), and acute disseminated encephalomyelitis (ADEM) cases diagnosed according to the 2017 McDonald criteria, the 2023 NMOSD diagnostic criteria, International MOGAD Panel proposed criteria. Results: The study was conducted in all tertiary, 7 regional, and 20 provincial hospitals across Mongolia and has collected comprehensive data on 965 patients. The prevalence of total demyelinating disorders was estimated to be 27.2, MS 15.6, NMOSD 5.6, MOG 0.06, and ADEM 0.9 per 100,000 total population, respectively. The prevalence of demyelinating disorders between provinces was compared in order of geographical latitude, from lowest to highest, and was statistically significant. Latitude is associated strongly with the prevalence of demyelinating disorders (p=0.006, 95% CI 14.3-22.4, Pearson correlation=0.603) and moderately with the prevalence of MS (p=0.028, 95% CI 9.39-15.6, Pearson correla tion=0.503). Conclusion In Mongolia, the prevalence of MS has significantly increased and can be considered at medium risk, but still much lower than that in Western countries. The prevalence of NMOSD is almost similar to other Asian countries. An obvious latitude gradient for demyelinating disorders was observed in the Mongolian population.

Background: The main risk factors for childhood overweight and obesity include the consumption of sugar-sweetened beverages and other sweetened foods. The sugar content of sugar-sweetened beverages was different from the nutritional information on the packaging. Aim: To determine sugar and brix content in domestic manufactured sugar-sweetened beverages, and compare information on the packaging and regulatory standards. Materials and Methods: The sugar and brix content in sugar-sweetened beverages was determined by laboratory anal ysis, including 150 domestically manufactured sugar-sweetened beverages. Laboratory analysis carried out in the Chemical toxicology laboratory of the National Reference Laboratory for Food Safety, MASM, determined sugar using a saccharometer and brix using refractometry. : Results: The study included 150 Mongolian sugar-sweetened beverages, including 20.7% (n=31) carbonated drinks, 47.3% (n=71) fruit drinks, 16.0% (n=24) tea drinks, 1.3% (n=2) energy drinks, 14.7% (n=22) flavored water. Sugar content 0.0–15.6% in sugar-sweetened beverages. The laboratory analysis results compared with information on the packaging 72.0% (n=108) difference between 0.1–11.3%, 10.7% (n=16) same, do not have sugar content in the nutritional information on the packaging 17.3% (n=26). Brix contained 0.2–13.0% carbonated drinks, 4.9–15.7% fruit drinks, 0.6–9.8% tea drinks, 7.7–16.0% energy drinks, and 0.1–9.7% flavored water. Conclusions 1. Sugar content 0.0–15.6%, brix 0.0–16.0% in Mongolian sugar-sweetened beverages. 2. The laboratory analysis results compared with nutritional information on the packaging 72.0% (n=108) difference between 0.1–11.3%, 10.7% (n=16) same nutritional information on the packaging, do not have sugar content in the nutritional information on the packaging 17.3% (n=26). 3. 37.3% of Mongolian sugar-sweetened beverages are unsatisfied with regulatory standards.

Introduction: Total environment 24 % of all estimated global deaths are linked to the environment. As of 2022, Ulaanbaatar has a population of 1,691,800, vehicles 435,725, thermal power plants 4, market and shopping centers 111, factories 13,465, and 225 gas stations. Also, 1.5 million tons of waste are generated annually, 1135.6 tons of coal are used, and environmental pollution is increasing year by year. Therefore, it is necessary to investigate the heavy metal contamination of the soil of Ulaanbaatar city and protect the health of the population. Purpose: To determine heavy metals pollution in the soil of Ulaanbaatar city Materials and Methods: We used descriptive research design in this study. Secondary data from Meteorological and Environmental Monitoring Department was used. The content of heavy metals such as lead (Pb), mercury (Hg), chromium (Cr), and cadmium (Cd)) in the soil was evaluated in comparison with the maximum permissible amount specified in the MNS 5850:2019 standard. Statistical analyzing was calculated using SPSS-25 software, and p<0.05 was considered statistically significant. Results: The average concentration of heavy metals in the soil of residential areas of 9 districts of Ulaanbaatar city is cadmium 0.43 mg/kg (min=0, max=26.6), mercury 0.22 mg/kg (min=0, max=4), chromium 11.2 mg/kg ( min=0, max=1609.6), lead is 24.4 mg/kg (min=0, max=257.2). Cadmium concentration in soil Bagakhangai (25%), Baganuur (19.7%), Khan-Uul (18.9%), lead concentration in Nalaikh (8.3%), Bayanzurkh (5.4%), Chingeltei (3.3), mercury concentration in Baganuur ( 24.7%), Khan-Uul (18.4%), and chromium concentration in certain locations of Khan-Uul (4.7%) districts exceeded the standards, respectively. The concentration of soil cadmium (21.2%) and lead (7.7%) near the technical market, mercury concentration (26.3%) near the market and shopping center, and chromium concentration (58.9%) near the central treatment plant exceeded the maximum permissible levels. Conclusion Cadmium and mercury pollution were mainly detected in the heavy metal pollution of the soil of Ulaanbaatar city, and there is heavy metal pollution in certain locations of Baganuur and Khan-Uul districts. Heavy metal pollution is caused by activities such as technical markets, auto repair shops, markets, shopping centers, and treatment plants.

Radon is a radioactive gas that has no smell, colour or taste. Radon is produced from the natural radioactive decay of uranium, which is found in all rocks and soils. Radon can also be found in water. Outdoors, radon quickly dilutes to very low concentrations and is generally not a problem. The average outdoor radon level varies from 5 Bq/m³ to 15 Bq/m³. However, radon concentrations are higher indoors and in areas with minimal ventilation, with highest levels found in places like mines, caves and water treatment facilities. In buildings such as homes, schools, offices, radon levels can vary substantially from 10 Bq/m³ to more than 10 000 Bq/m³.
The effects of residential radon on human health have been studied worldwide since the 1980s. In addition, studies conducted in Europe, North America, and China have proven that even radon levels in dwellings below the acceptable level can pose long-term risks to residents health and contribute to the development of lung cancer. Relying upon the average level of radon and the prevalence of cigarette smoking in the country, radon causes 3-14% of the total incidence of lung cancer. An increase of 100 Bq/m 3 in long time average radon concentration increases the risk of lung cancer by approximately 16%, which is considered that there is a linear relationship between radon concentration and lung cancer.

Introduction: On January 31, 2020, the World Health Organization (WHO) declared the infection with coronavirus (COVID-19) an “International Public Health Emergency” and on March 11, 2020, declared it a “Pandemic”. To date, the statistics of the total number of cases of COVID-19 infection is more than 676 million, and the number of deaths is more than 6.8 million. Therefore, reducing the mortality and spread of infection is an urgent issue for the world community. In March 2020, Mongolia confirms its first new case of COVID-19 imported by air transport from abroad. Since then, there have been over 1 million total cases of infection and 2,136 deaths. The aim of this study is to determine some outcomes related to the COVID-19 pandemic in Mongolia. Materials and Methods: We used descriptive research design in this study. Quantitative secondary data about causes of total mortality, COVID-19 cases during the pandemic were analysed from Health Development Center. Also, we conducted cross sectional study on concepts of long COVID-19 condition among 188 people who were recovered from their COVID-19 illness. The SPSS-23 software was used to analyze the data. Results: The mortality rate of the total population of Mongolia in 2021 was compared to this indicator for 2010, 2015, and 2020 and its growth rate was calculated. When calculating the mortality rate of the total population of Mongolia, the number of deaths per 10,000 population in 2021 was 47.4, which is an increase of 11% compared to 2020 in terms of growth rate. As for the causes of mortality growth, cardiovascular deaths increased by 16.7%, deaths of injuries and accidents by 8.2%, and deaths of respiratory diseases increased by 61.1% respectively. There was a positive medium correlation (p=0.007) between the number of cases of COVID-19 infection and the population total mortality.
A total of 188 people were included in the study, with a mean age of 38±12.3 years (minimum=18, maximum=70). Females were 51.1% (96), males were 48.9% (92), males were 6.9% (6.9%), and females were 13.3%. Long COVID-19 condition was found in 20.2% of the respondents. The duration of symptoms after infection with COVID-19 was (23.6%) 3 months, (21%) 1 year, and (23.6) still had symptoms. Symptoms such as fatigue, insomnia, cognitive decline (42.1%), shortness of breath (36.8%), cough, and heartburn appeared. Conclusions
1. During the COVID-19 pandemic in Mongolia, the total mortality of the population has increased, including pneumonia and heart attack. Total mortality of the population during the pandemic depended on the number of cases of COVID-19.
2. About one in five people with COVID-19 answered that observed long-term symptoms of COVID-19, such as fatigue, insomnia, shortness of breath, and cognitive changes, which were more common in women and people with chronic conditions.

Introduction: Air pollution is one of the greatest environmental risk to health. Ambient air pollution accounts for an estimated 4.2 million deaths per year due to stroke, heart disease, lung cancer and chronic respiratory diseases. Approximately 46% of the population resides in Ulaanbaatar, and over half of the population living in ger (traditional yurt dwelling) areas consumes raw coal, which leads to an increase in ambient air pollutants. The Government of Mongolia took a series of actions to reduce air pollution; one was the ban on the consumption of raw coal beginning on 15 May 2019. The aim of this study is to describe the Ulaanbaatar air quality related to briquettes usage during cold seasons. Material and Methods: We used ecological research design in this study. Quantitative data about air quality of Ulaanbaatar city during the cold seasons (Oct, Nov, Dec, Jan, Feb, Mar, Apr) in 2018-2020 years were analyzed from Department of air quality. These 5 indicators such as sulfur dioxide, nitrogen dioxide, particles (PM_2.5, PM₁₀) and carbon monoxide were selected for statistical analysis. The SPSS-20 software was used to analyze the data. Ethics: The methodology was approved by the Medical Ethics Sub-Committee of the Ach medical university on 5^th of February, 2021. Results: The average sulfur dioxide, nitrogen dioxide concentrations in the air have increased in October 2019–April 2020 compared to the previous five years. But carbon oxide, particular matter concentrations have decreased in the selected years. Sulfur dioxide (p <0.0001), nitrogen dioxide (p =0.001), PM₁₀(p <0.0001), and PM_2.5 (p <0.0001) are differentiated before and after the use of improved fuels by Wilcoxon signed rank test. However, the CO content did not differ from that of the briquette’s consumption (p =0.412). Conclusions During the cold seasons, the concentration of sulfur dioxide and nitrogen dioxide has increased in air of Ulaanbaatar after used briquettes, while the concentration of particulate matter has decreased during the cold seasons.

Introduction: Among the population of Mongolia, cardiovascular diseases (34.2%), cancer (24.3%), accidents and external causes (16.9%) are highly prevalent, and risk factors such as alcohol and tobacco use, unhealthy diet, lack of exercise have increased dramatically, and more than half of people aged 45-64, or 53.2% are at high risk of contracting non-communicable diseases. When comparing the demand for health care and services according to the level of healthcare institutions, it was determined that 70% of the demand is in the primary healthcare institution, 20% at the secondary level, and 10% at the tertiary level. Therefore, in order to prevent these diseases and provide health education to the population, it is necessary to study the attitude of the citizens who visit primary healthcare institutions about public health care and services. Material and Methods: In this study, a cross-sectional research design was used to determine citizens’ attitudes toward public health care and services. In collecting data, a total of 291 people from each of Dornod and Khovd provinces, from the capital of provinces, and 3 soums were included in the target sampling method. When evaluating the attitudes of the respondents, they were rated on a scale of 1-5 for each question. The SPSS-20 software was used to analyze the data. Ethics: The methodology was approved by the Medical Ethics Sub-Committee of the Ach medical university on the 30th of June, 2022 (Decision #22/05/04). Results: 51% (148) of respondents rated their health status as good and 42.1% (122) rated it as moderate, and 57.6% (167) of all respondents answered that they visit the primary health center when they have symptoms. Also, the status of visiting a primary health center for prevention is better in the following groups: 45-54 age group, among people with complete secondary and higher education, and soum healthcare center.
The attitudes of the participants towards public health care and services were evaluated in 4 groups, which are the demand for organizing preventive measures, the dependence of health on the individual, and the dependence of health on social and economic conditions, with an average of 4 points which means the demand is great. In addition, the healthcare institution’s organization of measures to promote and prevent the health of citizens is an average of 3.87 points, and the general score of the respondents’ attitude is 3.98 points, which indicates that there is a great demand for public health care and services. Conclusions Despite the low number of visits to primary health centers for preventive purposes among the respondents, attitudes toward public health care and services were good.

Background: However kidney transplantation has being performed in Mongolia since 2006, because of pre-transplant sensitization, ABO incompatibility, hepatitis B and C virus activation many patients are taken kidney transplantation in abroad. The transplantation centers use own immunosuppressive regimens. Objective: Our aim was to assess the immunosuppressive regimens efficacy and toxicity in kidney transplant Mongolian recipients. Methods: We analyzed data from 96 adult kidney transplant recipients who had taken kidney transplantation in different transplant centers from August 2006 through January 2014. There were 3 kinds of regimens Group I Simulect induction with standard triple /FK506/CyA+MMF/AZA+steroid/, Group II Campath-1H induction with CNI monotherapy and Group III Campath-1H induction with standard triple /FK506/CyA+MMF/AZA+steroid/. We retrospectively collected the post-transplant first two years serum creatinine. The study was performed in 2014. The questionnaire was taken and blood samples collected for determination of tacrolimus through level and for other laboratory tests. The primary end point was the first two years serum creatinine, the secondary end points included rejection episodes, blood through level of tacrolimus and some laboratory findings. Results: The post-transplant first two years serum creatinine levels were significantly different in 3 groups. Group III showed similar results compared to Group I. There was not enough data of biopsy proven acute rejection episodes however group II said more rejections occurred. However participants said that rejection occurred in 15 (15.6%) biopsy was done only 3 (3.1%) cases. Blood through level of tacrolimus was significantly different in three groups. Some laboratory findings showed different between three groups. Conclusions A regimen of Campath-1H induction with CNI monotherapy (Group II) may be advantageous for short-term renal function and cost effective but there were more rejection complications and increased creatinine. The regimen of Campath-1H induction 11 with standard triple (Group III) may be advantageous for long-term renal function, allograft survival, but there should consider about infection complications and polycythemia. Simulect induction with standard triple could be best choice but transplantations were performed in experienced centers. The study enrolled few cases and cases which were performed at the beginning of transplant program so many things could influence on the result. The study was compared beginner transplant center with experienced centers. Longitudinal cohort study needed in the future.