• Journal of Environmental Health Sciences
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• v.46 no.6
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• pp.685-693
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• 2020

Objectives: Recent data indicate that sensitization to mold contributes to the severity and persistence of asthma. The aim of this study was to investigate relationships between indoor mold concentrations and pulmonary function parameters in asthmatic children with mold sensitization. Methods: Asthmatic subjects who had a positive result in skin-prick testing to more than one mold allergen, such as Alternaria, Aspergillus, or Penicillium, were enrolled. Their pulmonary function and methacholine challenge test results were collected. Measurements of blood eosinophil, serum IgE, and fractional exhaled nitric oxide (FeNO) were taken. Indoor levels of VOC, CO2, PM10 and PM2.5 in each subject's house were measured. We counted mold and bacteria colonies from the subjects' house air samples. Results: The mean levels of FEV1, FVC, FEV1/FVC, and FEF25-75 were 82.8±19.7, 87.3±17.9, 85.8±8.3, and 82.3±28.9%, respectively. The mean FeNO level was 19.8±11.2 ppb and the geometric mean (range of one SD) of methacholine PC20 was 3.99 mg/mL (0.67-23.74 mg/mL). The average indoor air pollutant levels were below the recommended levels set by the Ministry of Environment for multiplex buildings. Indoor mold levels showed a significant inverse correlation with methacholine PC20, but not with the baseline pulmonary function parameters. Conclusion: Indoor mold concentrations are a risk factor for increased bronchial hyperresponsiveness among asthmatic children with mold sensitization. Targeted environmental intervention should be considered for selected asthmatic children with mold sensitization for avoiding severe airway hyperresponsiveness.

• Journal of odor and indoor environment
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• v.16 no.1
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• pp.47-53
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• 2017

Mold is one of the important bio-aerosols affecting human health in the indoor environment. To manage mold contamination, it is necessary to use an appropriate method for its detection and enumeration. Recently, the impaction method of ISO 16000-18 has been established as one of methods to detect and enumerate molds in air. To investigate the general use of the impaction method for mold detection in domestic indoor environments, the suitability of the method was assessed using different antibiotics, media and air samplers. All of the three antibiotics tested - ampicillin, chloramphenicol and streptomycin - showed inhibitory effects on bacterial colony formation on MEA and DG-18 media, without inhibiting mold growth. Of these three antibiotics, ampicillin was the most effective. There was no statistical difference between MEA and DG-18 media in the measurement of mold concentration. The formation of discriminative colony morphology was more apparent in DG-18 media. No significant difference in the measurement of mold concentration was found between Andersen samplers and MAS-100NT samplers, which are two major samplers introduced in Korea.

• Architectural research
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• v.8 no.1
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• pp.37-45
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• 2006

A fungal spore transportation model that accounts for the concentration of airborne indoor spores and the amount of spores deposited on interior surfaces has been developed by extending the current aerosol model. This model is intended to be used for a building with a mechanical ventilation system, and considers HVAC filter efficiency and ventilation rate. The model also includes a surface-cleaning efficiency and frequency that removes a portion of spores deposited on surfaces. The developed model predicts indoor fungal spore concentration and provides an indoor/outdoor ratio that may increase or decrease mold growth risks in real, in-use building cases. To get a more useful outcome from the model simulation, an uncertainty analysis has been conducted in a real building case. By including uncertainties associated with the parameters in the spore transportation model, the simulation results provide probable ranges of indoor concentration and indoor/outdoor ratio. This paper describes the uncertainty quantification of each parameter that is specific to fungal spores, and uncertainty propagation using an appropriate statistical technique. The outcome of the uncertainty analysis showed an agreement with the results from the field measurement with air sampling in a real building.

• Journal of Environmental Health Sciences
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• v.27 no.2
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• pp.1-9
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• 2001

This study was carried out to investigate the microbial characteristics of the urban air pollution in the subway stations, streets, department stores, wholesale markets, underground shopping centers, buildings, parks, houses and apartments in the Seoul and the suburbs area. Total cell count, total mold count and the presence of opportunistic pathogens(Streptococcus pneumoniae, Klebsiella pneumoniae, Aspergillus spp., Penicillium spp.) were evaluated determine the microbial air quality. Total cell count and mold count of indoor air in the houses and apartments were 2.9$\times$10$^2$-6.3$\times$10$^2$cfu/㎥ and 60-1.8$\times$10$^2$cfu/㎥, respectively, and the department stores and wholesale markets had much lower cell count than the houses and apartments. Ground level of commercial stations were 2.6 fold higher than the general subway stations, and Apergillus spp. and Penicillium spp. which could cause the bronchus and lung diseases were detected 17 sampling site out of 45. Dust were collected from the commercial facilities and houses, and total cell and mold count of the dust were 4.3$\times$10$^3$-1.7$\times$10$^{6}$ cfu/g and 2.3$\times$10$^3$-6.5 $\times$10$^4$cfu/g, respectively. Therefore the dust might be one of the main reservoir of microorganims.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.12
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• pp.852-857
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• 2012

Recently, the indoor air pollution by microbes such as fungi and mites have become a concern as important research topic on indoor air quality. Fungal growth is significantly affected by humidity. In this study, we examined the influence of relative humidity on the surface of building materials and the water content of building materials on the fungal growth rate by measuring the mycelium length of fungi in the fungal detector placed on the surface of building materials. As a result, even if the relative humidity on the surface of building materials is identical, the more water content of building materials is, the more fungi grow faster. It was suggested that fungal growth rate depends on not only the relative humidity on the surface of building materials but also the water content of building materials.

• Mycobiology
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• v.42 no.3
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• pp.286-290
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• 2014

Fungi are the known sources of irritation associated with atopic diseases (e.g., asthma, allergic rhinoconjunctivitis, and atopic eczema). To quantitatively estimate their presence in the indoor environment of atopic dermatitis-inflicted child patient's houses (ADCPHs), the high-efficiency particulate air (HEPA) filters installed inside the air cleaners of three different ADCPHs were investigated for the presence of mold. The air cleaner HEPA filters obtained from the three different ADCPHs were coded as HEPA-A, -B, and -C, respectively, and tested for the presence of mold. The colony forming units (CFUs) corresponding to the HEPA-A, -B, and -C filters were estimated to be $6.51{\times}10^2{\pm}1.50{\times}10^2CFU/cm^2$, $8.72{\times}10^2{\pm}1.69{\times}10^2CFU/cm^2$, and $9.71{\times}10^2{\pm}1.35{\times}10^2CFU/cm^2$, respectively. Aspergillus, Penicillium, Alternaria, Cladosporium, Trichoderma, and other fungal groups were detected in the 2,494 isolates. The distribution of these fungal groups differed among the three filters. Cladosporium was the major fungal group in filters HEPA-A and -C, whereas Penicillium was the major fungal group in the filter HEPA-B. Nine fungal species, including some of the known allergenic species, were identified in these isolates. Cladosporium cladosporioides was the most common mold among all the three filters. This is the first report on the presence of fungi in the air cleaner HEPA filters from ADCPHs in Korea.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.16-17
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• 2018

A few years ago, the rapid degradation of domestic air quality has led to the efforts of exhaust gas policy and fine dust mask, but it is not a fundamental measure. In Korea, photocatalyst will be applied to residential and multi-use facilites to purify indoor and outdoor air. Also, in this study, it is tried to produce exposed concrete that is aesthetically pleasing as well as air purification of indoor by combining with light transparent concrete according to the increasing interest in human indoor living environment. For this purpose, we have developed a block formwork for photocatalysis light transparent concrete and established a suitable manufacturing method for on-site construction.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.8
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• pp.683-689
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• 2003

The thermal comfort of an indoor swimming pool is different from that of general indoor space because of the characteristics of large space and the wear conditions of swimmers. Dew condensation by humid air not only makes mold on the floor, wall and roof but also decreases the durability of buildings by penetrating into their structures. In this study, the characteristics of the flow field, the temperature field and the humidity distribution in an indoor swimming pool have been examined by the numerical method to estimate the level of thermal comfort and the generation rate of dew condensation. The results showed that the dew condensation regions were spread widely at the eastern parts of the swimming pool due to the insufficient air flow rate with low velocity and temperature. To prevent the generation of dew condensation in a region, a sufficient warm air flow rate should be supplied to make an air mixing. The values of PMV at horizontal plane of 1.5 m height have the range of -1.0∼1.2, which means the suitable level for swimmers.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.4
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• pp.382-392
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• 2018

Objective: Allergic diseases such as asthma due to fungal exposure in houses have increased, and proper management is urgent. Mold can grow in the air, floor, walls, and other areas according to environmental conditions, and there are many limitations to the conventional methodology for examining fungal exposure. For this reason, the degree of fungal contamination is being evaluated by ERMI (Environmental Relative Moldiness Index), a quantitative analysis method proposed by the EPA. In this study, we compared ERMI values between water-damaged dwellings and non-damaged ones to evaluate the effectiveness of Korean ERMI values. We also explored the association of ERMI values with the level of airborne mold and characteristics of dwellings. Methods: Floor dust was collected after installing a Dustream collector on the suction port of a vacuum cleaner. The collected samples were filtered to remove only 5 mg of dust, and DNA was extracted using the FastDNA SPIN KIT protocol. Results: The ERMI values were found to be 19.6 (-6.9-58.8) for flooded houses, 7.5 (-29.2-48.3) for leaks/condensation, and 0.8 (-29.2-37.9) for non-damaged dwellings. The airborne concentration of mold for flooded, leakage or condensed, and non-damaged houses were $684CFU/m^3$, $566CFU/m^3$, and $378CFU/m^3$, respectively. The correlation between ERMI values and the levels of airborne mold was low (R = 0.038), but a weakly significant association of the ERMI values with the concentration of particulate matter ($PM_{10}$) was observed as well(R=0.231,P<0.05). Conclusions: Our findings show that the reference value using ERMI can be used to distinguish water-damaged and non-damaged dwellings. It is believed that ERMI values could be a promising tool for assessing long-term fungal exposure in dwellings.

• Journal of Environmental Science International
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• v.21 no.6
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• pp.677-685
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• 2012

The elevator is needed healthy and comfortable indoor air quality (IAQ) for using many people, but we found nothing about IAQ studies of an elevator. In general, air in the elevator car is sucked from the elevator's hoistway straight into the car using a fan. The air sucked into the hoistway may be filled with dust, mold and bacteria. This study was performed to measure of characteristics of indoor air quality (PM10, falling bacteria, $CO_2$, Rn and HCHO) in elevator's hoistway, CAR and lobby of 8 sites (4 apartments and 4 commercial buildings) in Gyeongnam from May, 2010 to January, 2011. With regards to the differences of pollutant distribution among hoistway, CAR, and lobby, the concentration of Rn and HCHO were the highest in hoistway followed by CAR and lobby, and PM10, falling bacteria and $CO_2$ were the highest in CAR followed by hoistway and lobby. Mean concentrations of PM10 were 104.9 ${\mu}g/m^3$ in CAR, 92.3 ${\mu}g/m^3$ in hoistway and 68.2 ${\mu}g/m^3$ in lobby, respectively.