This study aims to enable early detection of low-concentration airborne respiratory viruses in multi-use facilities using a cyclone-based air sampler (Coriolis® m , Bertin). To achieve this, bacteriophage MS2 of Escherichia coli was aerosolized into a chamber at varying concentrations, reflecting levels observed in indoor environments. The rationale for differentiating viral concentrations was to assess field applicability and optimize sampling conditions. Sampling efficiency was maximized by adjusting sampling time, flow rate, and media volume to determine optimal detection parameters. The effectiveness of the optimized conditions was further validated through cross-validation using Influenza A and field testing. Field experiments conducted on 10 samples across five locations confirmed airborne virus detection in one of the samples (10%), demonstrating the feasibility of the cyclone-based air sampler method for airborne virus collection and detection.

Wood ear mushroom (Auricularia heimuer) is one of the most popular mushrooms in Korea. Bacteria in the air can act as contaminants of mushroom media, mushroom pathogens, and sources of food poisoning in the indoor environment of mushroom cultivation houses. Therefore, cultivation houses require proper management to maintain mushroom production, quality and hygiene. This study was conducted to evaluate the properties of airborne bacterial species isolated from wood ear mushroom cultivation. Nine species of indoor-airborne bacteria were tested against wood ear mushroom cultivars using confrontation assay on PDA. Among 9 species, Bacillus subtilis DUCC18238 showed the strongest inhibition effect on the mycelial growth of nine wood ear mushroom cultivars and the inhibition rate for 7 of them was more than 30%. In addition, B. subtilis DUCC18238 inhibited the mycelial growth of 11 out of 18 wild mushroom species, 7 out of 8 phytopathogenic fungi, and 5 out of 5 Trichoderma species, respectively. The results of this study show that the management of airborne bacteria in the indoor environment of wood ear mushroom cultivation houses is necessary.

This review paper provides a comprehensive analysis of the measurement and distribution of microplastics in the atmosphere and their role in the adsorption and transport of organic and inorganic pollutants. Due to their small size, large surface area, and hydrophobic nature, microplastics can adsorb a wide range of pollutants, including volatile organic compounds (VOCs) and heavy metals. These pollutants, strongly bound to the surface of microplastics, can remain suspended in the atmosphere for extended periods, facilitating the widespread distribution of contaminants. Building on existing research, this paper systematically reviews the sampling, pretreatment, and analytical methodologies applied to study microplastics in the air. Furthermore, it examines the influence of environmental factors on the adsorption and desorption dynamics of pollutants associated with microplastics. Various studies indicate that microplastics can interact with pollutants such as heavy metals, organic compounds, and microorganisms to form complex contaminants. These complexes can be transported and redistributed across long distances in the atmosphere, amplifying their environmental and health impacts. This review highlights that microplastics are not merely a pollutant themselves but serve as a vehicle for the migration and dispersion of other contaminants. This dual role emphasizes the significant risks microplastics pose to public health and the environment, necessitating further research and effective mitigation strategies.

This study was carried out to get information on the concentration and species of airborne fungi in wood ear mushroom (Auricularia heimuer) cultivation houses. Air samplings were conducted at three wood ear mushroom farms located in Iksan and Wando in 2022. Two out of the three cultivation houses exceeded the Ministry of Environment’s recommended indoor air quality standards for fungi concentration in multi-use facilities. A total of 12 genera and 15 species of airborne fungi were isolated and identified. There were species belonging to 6 genera at the genus level. Overall, the genus Cladosporium accounted for the majority with three species. Among the identified species, there were fungi that affect the human body, such as Aspergillus niger, Lichtheimia ramose, and Rhizomucor pusillus, as well as Alternaria alternata, Cladosporium ramotenellum, Cladosporium subuliforme, and Curvularia lunata, which cause diseases in plants. Penicillium brevicompactum was detected as a fungus affecting mushroom cultivation. This study is the first report in Korea on airborne fungi in wood ear cultivation houses and provides useful information for environmental hygiene management of cultivation houses.

모기류는 흡혈을 통해 원충, 바이러스, 사상충 등 다양한 병원체를 보유하며 말라리아, 일본뇌염, 웨스트나일열, 뎅기열 등을 사람에게 매 개하는 위해성이 있는 위생해충이다. 이번 연구에서는 해외유입 모기류 감시를 위해 경상남도 고성군에 스마트 고공포집기를 설치하여 2022년 부터 2023년까지 모기류들을 모니터링하였다. 조사기간 동안, 총 3속 5종 43개체가 채집되었으며, 이중 삼일열말라리아를 매개하는 벨렌얼룩날 개모기(Anopheles belenrae)를 경남 지역에서 처음으로 발생함을 확인하였다. 본 연구에서는 스마트 고공포집기를 통해 해외에서 유입가능한 모 기류에 대한 실시간 모니터링이 가능함을 확인하였다.

Airborne bacteria are an important environmental factor that affects the hygiene of mushroom cultivation houses, as they can act as contaminants or pathogens in mushroom cultivation. To determine the distribution of airborne bacteria in the air of wood ear mushroom cultivation houses, air sampling and temperature and humidity measurements were conducted at three wood ear mushroom farms located in Iksan and Wando in 2022. Sampled air was analyzed to measure bacterial concentration levels and identify bacterial species. There was no significant difference in temperature and humidity changes detected between the three mushroom growing houses. Additionally, the concentration of bacteria in the air did not exceed 800 CFU/m², which is the maximum amount of airborne bacteria allowed by the Ministry of Environment’s indoor air quality maintenance standards. Eleven species of bacteria belonging to 11 genera were isolated and identified from air samples. These include five species of Micrococcales, four species of Bacilli, one species of Actinomycetia, and one species of Mycobacteriales. Of the 11 species identified, five are known to affect human health. However, no mushroom pathogens or species causing food poisoning were found.

The present study was carried out to investigate the concentration and species diversity of airborne fungi in thermophilic mushroom cultivation houses. Fungal concentration measurements were performed in April and May 2022 for a Pleurotus ostreatus cultivation house, in July and August 2023 for a Pleurotus sajor-caju and Agaricus blazei cultivation house, and in June, July and August 2023 for a Pleurotus pulmonarius, Pleurotus sajor-caju and Calocybe indica cultivation house. The airborne fungal concentration was 2.95 × 102 CFU/m3~105CFU/m3, above 105CFU/m3, and 1.12 × 103 CFU/m3~ 9.17 × 103 CFU/m3 in the three cultivation houses, respectively. A total of 8 genera and 22 species of airborne fungi were isolated from three mushroom cultivation houses. 5 genera and 7 species were identified from P. ostreatus cultivation house. Furthermore, 4 genera 6 species were found from A. blazei and C. indica cultivation house. In addition, 5 genera and15 species were isolated from P. pulmonarius, P. sajor-caju and C. indica cultivation house. Among the fungi isolated, the class of Eurotiomycetes was the most common. Among the 22 fungal species, Aspergillus flavus, A. ochraceus A. sydowii, A. tubingensis, A. westerdijkiae, Penicillium brevicompactum, P. citrinum, and P. steckii have been reported as harmful species to mushrooms, food, and human.

Airborne bacteria in mushroom growing environments are a potential risk of contamination in commercial mushroom production. Controlling contamination in mushroom farms requires understanding the bacterial ecology in the cultivation environment. This study was conducted to investigate the concentration and species diversity of floating bacteria in a thermophilic mushroom cultivation room. Temperature, humidity, temperature, humidity, and bacterial concentration measurements were performed in April and May 2022 for a Pleurotus ostreatus cultivation house, in July and August 2023 for a Pleurotus sajor-caju and a Agaricus blazei cultivation house, and in June, July and August 2023 for a Pleurotus pulmonarius, Pleurotus sajor-caju and Calocybe indica cultivation house. The airborne bacterial concentration was 5.27 × 103~105 CFU/m3, 3.81 × 102 ~1.37 × 103 CFU/m3, and 2.55 × 102 ~1.37 × 102 CFU/m3 in the three cultivation houses, respectively. A total of 23 genera and 37 species of airborne bacteria were isolated from the three mushroom cultivation houses. 12 genera and 18 species were identified from P. ostreatus cultivation house. Furthermore, 4 genera and 4 species were found from A. blazei and C. indica cultivation house. In addition, 11 genera and 18 species were isolated from P. pulmonarius, P. sajor-caju and C. indica cultivation house. Among the bacteria isolated, the Bacilli class was the most common, followed by Gammaproteobacteria. Among the 37 bacterial species, it was determined that Bacillus cereus, B. licheniformis, Cedecea neteri, Exiguobacterium acetylicum and Raoultella terrigena could negatively affect humans or foodstuff. Cedecea neteri is also known to cause diseases among mushrooms.

The levels of Indoor radon can increase in newly built apartments that mainly use construction materials such as concrete. However, radon measurement in newly built buildings has only been implemented recently, and there is a lack of sufficient data for radon management purposes. This study aimed to determine the levels of indoor radon in newly built apartments by regions, sizes of household, and floor (lower, middle, upper floor), and to explore the trend of radon reduction by time according to ventilation methods. Indoor radon was measured in 48 households in four regions (Gyeonggi-do and Gangwon-do). Measurements were performed for 48 hours and 24 hours under closed and ventilated conditions using real-time measurement devices FRD400 and RAD7, respectively. To analyze changes in radon concentration by floors, data were collected by dividing households into lower, middle, and upper floors according to their vertical height. The concentrations of indoor radon ranged from 12.1 Bq/m3 to 559.0 Bq/m3 when windows were closed and 12.0 Bq/m3~500.0 Bq/m3 when ventilated (including both mechanical and natural ventilation). On average, the concentration of closed conditions of household when sealed (arithmetic average 185.3 Bq/m3) was 1.5 times higher than the concentration during ventilation (including mechanical and natural ventilation: 123.8 Bq/m3), and around three times higher than the average for mechanical ventilation (65.7 Bq/m3). It was found that the indoor radon concentration statistically increased as the height increased and the size of the house became smaller. Typically, it took 7 to 8 hours to exceed the standard of 148 Bq/m3 after windows were closed. It decreased to less than 148 Bq/m3 within 3 to 4 hours after operating the mechanical ventilation system. However, in the case of natural ventilation, it takes more than 24 hours to reach below the standard value, and the concentrations stagnated after 24 hours. In conclusion, radon concentration in narrow spaces can be relatively high if ventilation is not sufficient due to the nature of apartments with wall-type structures. Therefore, it is necessary to prepare various radon reduction measures according to floor, size, and ventilation methods.

This study was carried out to examine the concentration and distribution characteristics of total airborne bacteria (TAB) and airborne mold in non-regulated public-use facilities. The arithmetic mean (AM) of the TAB in all facilities was 356.5 ± 419.3 CFU/m3, and the geometric means (GM) was 157.8 CFU/m3, which did not exceed the standard value of 800 CFU/m3. The highest concentration was 637.3 ± 372.0 CFU/m3 (GM: 534.9 CFU/m3) in the underground shopping mall. The AM of airborne mold in all facilities was 448.2 ± 429.6 CFU/m3 (GM: 285.4 CFU/m3), which did not exceed the standard value of 500 CFU/m3, but was close to it. In particular, subway station (AM: 661.5 ± 441.2 CFU/m3, GM: 540.0 CFU/ m3), large-scale store (AM: 587.6 ± 683.2 CFU/m3, GM: 297.8 CFU/m3), and private educational institute (AM: 528.8 ± 379.6 CFU/m3, GM: 373.7 CFU/m3) exceeded the standard. Operational taxonomic unit of 16S rDNA and ITS2 rDNA region was analyzed to profile bacteria and mold component in the air of the public-use facilities. As a result, Pseudomonas and Morganella are the major bacterial groups. Regarding mold, Aspergillus, Candida, Malassezia, and Penicillium are the major groups. Component of each airborne bacterial and mold groups varied depending on the type of public-use facilities.

Following the social requirement to strengthen field supervision of the asbestos containing materials (ACM) abatement process with regard to asbestos school buildings, this study was conducted to understand the status and characteristics of airborne asbestos that may potentially occur after the ACM abatement process is completed. In the area where a series of asbestos abatement processes were finally completed, comprehensive area air sampling was performed. For sample analysis, Transmission Electron Microscopy (TEM) was used according to The Asbestos Hazard Emergency Response Act (AHERA) method and Phase Contrast Microscopy (PCM) analysis was also performed. Airborne asbestos was detected in 29.5% of the total samples, and the average concentration was 0.0039 ± 0.0123 s/cc (12.3 ± 38.9 s/mm2). 4.5% of the total samples exceeded the AHERA standard (70.0 s/mm2) and the average concentration was 0.0528 ± 0.0256 s/cc (167.2 ± 82.0 s/mm2). Airborne asbestos was no longer detected at the point when AHERA is exceeded after re-cleaning. Most of the detected asbestos was chrysotile (94.4%) and the structure types of asbestos were Matrix (41.4%), Fiber (39.9%), Bundle (10.8%), and Cluster (7.8%). Among the asbestos structures detected through transmission electron microscope analysis, the asbestos structures satisfying PCM-equivalent structures were found to be 6% of the detected asbestos, indicating that there is a limitation of the PCM analysis to check the airborne asbestos in that area. As a result of reviewing the status of airborne asbestos that may potentially occur and the type and dimensions of asbestos structure detected in the area, since the airborne asbestos exposure caused by poor field supervision for the ACM abatement process could not be ruled out, thorough management is necessary. In addition, the result of this study could be used as scientific evidence for establishing and strengthening policies related to ACM abatement, including cases of school buildings.

This study was carried out to investigate how airborne bacteria are distributed under different temperature conditions while cultivating oyster mushrooms by setting the indoor temperature of the cultivation room to 10°C, 15°C, 20°C, 25°C, and 30°C. The surveys were conducted in April and May, respectively. Airborne bacterial concentrations were distributed in the range of 1.61 × 102 ~ 3.67 × 102 CFU/m3 in April and 5.47 × 102 ~ 7 × 103 CFU/ m3 in May. In May, the indoor air quality maintenance standard (8.0 × 102 CFU/m3) was exceeded in the 10°C, 20°C, and 25°C cultivation rooms. Bacterial concentrations increased significantly in May compared to April. Bacterial concentrations were different between the cultivation rooms at different temperatures. The difference was more pronounced in May than in April. A total of 15 genera and 20 species were isolated from the indoor air of the oyster mushroom cultivation rooms. Overall, it was most abundant in Actinomycetia. Among the species identified, Agrobacterium radiobacter, Brevundimonas vesicularis, Kocuria palustris, K. salsicia, Lysinibacillus fusiformis, and Sphingobacterium siyangense are known to affect human health. This is the first report of airborne bacteria in cultivation rooms at different temperatures used for oyster mushroom cultivation. The results of this study are expected to be used as basic data to understand the indoor environment of thermophilic mushroom cultivation facilities.

Distribution of airborne bacteria in the entire regions of South Korea was investigated and analyzed by region and type of multi-use facilities. At first, 10 public facilities were selected including general restaurant, retail store, public transport, retail market, apartment house, underground parking lot, financial institution, business facility, educational institution, and public toilet, which are located at the regions such as Seoul, Busan, Daejeon, Gwangju, Gyeonggi, Jeju, and Gangwon. The regional distribution of the floating bacteria was identified that Micrococcus sp. was highly prevalent in Seoul (21.5 percent). In Daejeon, Bacillus sp. was highly prevalent (12.4 percent). In Busan, Micrococcus sp. was highly prevalent (22.8 percent). In Gwangju, Bacillus sp. was 9.35%. In Gyeonggi, Micrococcus sp. was 13.7%, and in Gwangju and Jeju, Micrococcus sp. was 11.2 percent and 92%. All in all, Micrococcus sp. and Bacillus sp. were highly detected throughout the entire region and multi-use facilities. Next, whether or not these airborne bacteria could influence the health of people was examined using HaCat human skin cell line which is human epithermal Karatinocytes related to allergic dermatitis. Among these isolated microorganisms, the HaCat cell proliferation was decreased by Arthrobacter sp., Bacillus sp., Brachybacterium sp., Brevundimonas sp., Kocuria sp., Mammaliicoccus sp., Norcardia sp., Prestia sp., Phychrobacillus sp., and Rhodococcus sp., while it was affected by the other bacteria. Therefore, these results have suggested that the airborne floating bacteria could be considered as the marker for the environmental risk management against atopic dermatitis, and it is needed for controlling the bacteria number that suppressed the proliferation of HaCat cells.

Although airborne wear particles (AWPs) generated from wheel-rail contacts are the major source of particulate matter (PM) in subway systems, studies on reducing the generation of such particles in order to enhance air quality are extremely rare. Therefore, this study investigated the effect of applying water-lubricant (applying tap water) on improving air quality by reducing the mass concentration (MC) of AWPs from wheel-rail contacts at a train velocity of 73 km/h using a twin-disk rig. An optical particle sizer was used to measure the MC of particles with the diameter range of 0.3 μm~10 μm. The results showed that the generation trends regarding PM1, PM2.5, and PM10 were different for dry and water-lubricated conditions: all three PMs showed an increasing-decreasing trend with slip rate under dry conditions; however, they were almost constant with slip rate under water-lubricated conditions. The particle size distributions were also different for dry and water-lubricated conditions: the peak occurred in multi-modal with the largest peak at approximately 6 μm in diameter under dry conditions; whereas, the peak occurred in bi-modal with the largest peak at approximately 0.9 μm in diameter under water-lubricated conditions. In addition, MCs were mostly smaller under water-lubricated conditions than dry conditions except at approximately 0.9 μm in diameter. Applying water significantly decreased PM1~2.5 and PM2.5~10 by more than 95%. This caused a decrease in PM2.5 and PM10 by 48.1% and 78.5%, respectively. On the other hand, applying water increased PM0.3~1 (i.e., PM1) by 52.8%, possibly owing to the effect of water vapor and mineral crystals from tap water. Overall, these findings indicate that water-lubrication can improve air quality in subway systems by reducing the MC of APWs generated from wheel-rail contacts. This study may provide a reference for future studies seeking to improve air quality in subway systems by reducing AWPs generated from wheel-rail contacts by applying lubricants.

A field study was conducted to reduce airborne bacteria by supplying active ions to indoor spaces used by vulnerable human groups spending substantial amounts of time in places such as schools and hospitals. In an experiment conducted during school hours (8:00-15:00), the average number of airborne bacteria in classrooms was 345.53 CFU/m3 or more without active ions. However, ion supply reduced the airborne bacteria to an average of 113.23 CFU/m3, indicating an efficiency of 61.61%. As a result of tests in 33 rooms used for surgery in small and middle sized hospitals, ion supply for 2 to 4 hours reduced the average airborne bacteria concentration from 243.88 CFU/m3 to 104.34 CFU/m3, representing a 41.53% reduction. A laboratory test to confirm the ion activity has shown that the mortality rate of E. coli used as a test bacterium increased with exposure time to ions. The initial colony number of E. coli was 251 CFU, but decreased to 4 CFU after 60 minutes of exposure to active ions. Therefore, it was confirmed that the supply of active ions can contribute to the control of airborne bacteria in the indoor environment of schools, hospitals and other public facilities.

As modern society has emerged and developed, the subway has established itself as a representative means of transportation in the city due to its speed, accuracy, and accessibility. According to the Indoor Air Quality Management Act, underground stations have established and managed the maintenance and recommendation standards for PM10, PM2.5, CO2, CO, HCHO, NO2, Rn, VOCs However, th the standards for airborne mold has not been applied for subway stations even though management for the health effect of exposure to mold is necessay. In this study, the correlation with major contributing factors was analyzed by measuring the concentration of airborne molds in the indoor air of underground stations and through literature research. It was confirmed that there was a correlation between the concentration of airborne molds in subway stations and the major contributing factors. As a result of the analysis, it was found that the concentration of airborne molds became higher as the location of the platform became deeper underground, during periods of congestion, and especially in summer. There was no significant correlation with the year of construction. Our findings indicate that appropriate management measures should be devised in response to such contributing factors.

Airborne bacteria are expected to float in the mushroom cultivation house, as it is a special environment with high humidity and high temperatures. Their concentration and diversity in the indoor air of the cultivation house could effect the health of farmers and the quality of mushrooms. To examine whether microbiota of airborne bacteria change from year to year, we measured the indoor temperature, humidity, and airborne bacterial concentration from mushroom cultivation houses located in six regions in Korea from 2020 to 2021, and isolated and identified airborne bacteria. The surveyed data were compared and the bacterial diversity of the 1st year and the 2nd year were determined. Based on the average temperature and humidity data surveyed, it can be seen that the temperature and humidity environment in the cultivation houses is such that bacteria can easily reproduce. It was observed that the temperature inside the cultivation houses tends to be higher or lower depending on the season and correlates with the temperature outside the cultivation houses. In the first year survey, 32 species of 20 genera were identified, and in the second year survey, bacteria belonging to 29 species of 22 genera were identified. Among them, the most detected species were all species belonging to the genus Bacillus. There were only three species (Bacillus altitudinis, Brevibacterium frigoritolerans, and Staphylococcus epidermidis) that were continuously isolated in common. Our results showed that the species of floating bacteria greatly vary from year to year even for the same cultivation houses.

This study was conducted to help manage total floating bacteria and fungi in the indoor air by studying the characteristics of total floating bacteria and fungi according to the indoor CO2 concentration of daycare centers. The sampling and analysis of samples was based on the indoor air quality process test method, and the result analysis was conducted using the SPSS statistical program to perform correlation and regression analysis. Correlation and regression results show that CO2 and total airborne bacteria showed positive relationships, but airborne mold did not show relevance. In addition, in order to identify factors affecting airborne mold, correlation analysis and regression analysis were performed regarding total airborne bacteria, PM10, PM2.5, HCHO, outdoor mold, I/O ratio, indoor temperature/ humidity, area per classroom and volume. The results showed that the factors affecting airborne mold were I/O ratio, outdoor airborne mold, and total airborne bacteria. Research results show that CO2 and total airborne bacteria can be reduced and controlled by natural ventilation, and in the case of airborne mold, mechanical forced ventilation such as hoods will be necessary due to the introduction of outdoor airborne mold. In addition, it is necessary to consider I/O ratio criteria in order to confirm effective indoor mold contamination, taking into account the effect of outdoor mold inflow.