• Safety and Health at Work
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• v.1 no.2
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• pp.183-191
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• 2010

Objectives: The objective of this study is to investigate the distribution patterns and exposure concentrations of bioaerosols in industries suspected to have high levels of bioaerosol exposure. Methods: We selected 11 plants including 3 livestock feed plants (LF industry), 3 metal working fluids handling plants (MWFs industry), and 5 sawmills and measured total airborne bacteria, fungi, endotoxins, as well as dust. Airborne bacteria and fungi were measured with one stage impactor, six stage cascade impactor, and gelatin filters. Endotoxins were measured with polycarbonate filters. Results: The geometric means (GM) of the airborne concentrations of bacteria, fungi, and endotoxins were 1,864, $2,252\;CFU/m^3$, and $31.5\;EU/m^3$, respectively at the sawmills, followed by the LF industry (535, $585\;CFU/m^3$, and $22.0\;EU/m^3$) and MWFs industry (258, $331\;CFU/m^3$, and $8.7\;EU/m^3$). These concentrations by industry type were significantly statistically different (p < 0.01). The ratio of indoor to outdoor concentration was 6.2, 1.9, 3.2, and 3.2 for bacteria, fungi, endotoxins, and dust in the LF industry, 5.0, 0.9, 2.3, and 12.5 in the MWFs industry, and 3.7, 4.1, 3.3, and 9.7 in sawmills. The respiratory fractions of bioaerosols were differentiated by bioaerosol types and industry types: the respiratory fraction of bacteria in the LF industry, MWF industry, and sawmills was 59.4%, 72.0%, and 57.7%, respectively, and that of fungi was 77.3%, 89.5%, and 83.7% in the same order. Conclusion: We found that bioaerosol concentration was the highest in sawmills, followed by LF industry facilities and MWFs industry facilities. The indoor/outdoor ratio of microorganisms was larger than 1 and respiratory fraction of microorganisms was more than 50% of the total microorganism concentrations which might penetrate respiratory tract easily. All these findings suggest that bioaerosol in the surveyed industries should be controlled to prevent worker respiratory diseases.

• Culinary science and hospitality research
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• v.22 no.8
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• pp.149-156
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• 2016

The purpose of this study is to reduce the contaminants (total volatile organic compounds (TVOCs), fine particle, odor and total airborne bacteria) during cooking process in cooking chamber, and to decrease the health damage in indoor space that has bad work environment. In order to solve the shortcomings of existing air purifiers and remove all kinds of pollutants effectively, this study focused on the development of indoor air purifiers which are made of bar type. Bio-ceramics filter which combines activated carbon and loess. The air cleaners developed with 4 measuring items including TVOCs, particulate matter, complex odor and total airborne bacteria were measured comparing their pre-service test to their post-service test after a period of time. The measured results showed higher removal efficiency of 91.02% as the concentration of TVOCs was reduced from $2,500{\mu}g/m^3$ to $223{\mu}g/m^3$. Second, the particulate matter removal ratio was 97.51% efficient with average concentration of $26.68{\mu}g/m^3$. Third, the odor showed 95.20% reduction as air dilution ratio averaged out at 144. Last, total airborne bacteria was eliminated by over 94% showing the changeable concentration from $787{\sim}814CFU/m^3$ to $47{\sim}40CFU/m^3$. In addition, the removal rate of harmful pollutants is excellent, and it is expected that the environment of the existing poor cooking room will be greatly improved by using the developed air purifier in combination with the ventilation device and the stove hood.

• Journal of Environmental Health Sciences
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• v.31 no.2 s.83
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• pp.120-126
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• 2005

To assess exposure of allergy patients to a biological environment, measurements were made of levels of airborne bacteria and fungi, house dust endotoxin and mite allergens in homes of 7 allergy patients and 12 healthy families. Concentrations of airborne total bacteria and the ratio of indoor and outdoor concentrations(I/O) in allergy patient's homes were high compared to non-allergy houses. But no significant differences could be shown for the concentration of spores of viable fungi and staphylococcus in indoor air between the homes of allergic patients and healthy families. The results of investigation on house dust mites, Dermatophagoids farinae were detected in all mattress samples and the levels in the allergy patient's homes were generally high, with individual measurements exceeding $2{\mu}g/g$ dust found in $30\%$ samples. In contrast with, Dermatophagoids pteronyssinus were detected in only $60\%$ samples and the concentrations were very low. The levels of endotoxin in dust samples collected from the allergy patient's home mattresses were higher than those of control houses. There was a positive correlation between the endotoxin levels and the house dust mite allergens.

• Advances in environmental research
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• v.2 no.1
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• pp.61-80
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• 2013

Quantification of viable forms of microbial community (bacteria and fungi) using culture-dependent methods was done in order to characterize the indoor air quality (IAQ). Role of those factors, which may influence the concentration of viable counts of bacteria and fungi, like ventilation, occupancy, outdoor concentration and environmental parameters (temperature and relative humidity) were also determined. Volumetric-infiltration sampling technique was employed to collect air samples both inside and outside the schools. As regard of measurements of airborne viable culturable microflora of schools during one academic year, the level of TVMCs in school buildings was ranged between 803-5368 cfu/$m^3$. Viable counts of bacteria (VBCs) were constituted 63.7% of the mean total viable microbial counts where as viable counts of fungi (VFCs) formed 36.3% of the total. Mean a total viable microbial count (TVMCs) in three schools was 2491 cfu/$m^3$. Outdoor level of TVMCs was varied from 736-5855 cfu/$m^3$. Maximum and minimum VBCs were 3678-286 cfu/m3 respectively. Culturable fungal counts were ranged from 268-2089 cfu/$m^3$ in three schools. Significant positive correlation (p < 0.01) was indicated that indoor concentration of viable community reliant upon outdoor concentration. Temperature seemed to have a large effect (p < 0.05, p < 0.01) on the concentration of viable culturable microbial community rather than relative humidity. Consistent with the analysis and findings, the concentration of viable cultural counts of bacteria and fungi found indoors, were of several orders of magnitude, depending upon the potential of local, spatial and temporal factors, IO ratio appeared as a crucial indicator to identify the source of microbial contaminants.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.288-293
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• 2007

To evaluate effects of airborne microorganisms in fresh cut processing plant, microorganisms in air, equipments, raw material, water and final product were isolated and identified using Vitek (R)2 compact system. Airborne microorganisms were isolated from 1000L air using air sampler for floating microorganisms and plate count agar for falling microorganisms. And contaminated microorganisms of equipment, water, and product were isolated from plate count agar plate. Total plate counts for floating and falling, raw material, equipments and final product were $10^2-10^3CFU/m^3,{\sim}10^1CFU/plate,\;10^3CFU/g,{\sim}10^4CFU/cm^2\;and\;10^4CFU/g$, respectively. From the result of isolated microorganism identification from raw material to final product, airborne microorganisms could affect the flora of final product.

• Journal of Animal Science and Technology
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• v.64 no.3
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• pp.539-563
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• 2022

Nine pig farms were evaluated for the welfare quality in Korea using animal- and environment-based parameters (particularly air quality parameters) during the winter of 2013. The Welfare Quality^® (WQ^®) protocol consists of 12 criteria within four principles. The WQ^® protocol classifies farms into four categories ranging from 'excellent' to 'not classified'. Each of these criteria has specific measures for calculating scores. Calculations for the welfare scores were conducted online using the calculation model in the WQ^® protocol. Environment-based parameters like microclimate (i.e., temperature, relative humidity, air speed, and particulate matter), bacteria (total airborne bacteria, airborne total coliform, and airborne total Escherichia coli), concentration of gases (carbon dioxide, ammonia, and hydrogen sulfide) were measured to investigate the relationship between animal- and environment-based parameters. Correlations between the results of animal- and environment-based parameters were estimated using spearman correlation coefficient. The overall assessments found that five out of nine farms were 'acceptable', and four farms were 'enhanced'; no farm was 'not classified'. The average score for the four principles across the nine farms, in decreasing order, were 'good feeding' (63.13 points) > 'good housing' (59.26 points) > 'good health' (33.47 points) > 'appropriate behaviors' (25.48 points). In the result of the environment aspect, the relative humidity of farms 2 (93.4%), 3 (100%), and 9 (98%) was much higher than the recommended maximum relative humidity of 80%, and four out of the nine farms had ammonia concentrations greater than 40 ppm. Ammonia had negative correlations with 'positive social behaviors' and positive emotional states: content, enjoying, sociable, playful, lively, happy and it had positive correlations with negative emotional states: aimless, distressed. The concentration of carbon dioxide had negative correlations with positive emotional states; calm, sociable, playful, happy and it had a positive correlation with negative emotional state; aimless. Our results indicate that the control of the environment for growing pigs can help improve their welfare, particularly via good air quality (carbon dioxide, ammonia, hydrogen sulfide).

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.3
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• pp.457-463
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• 2013

The purpose of this study was to apply the Hazard Analysis Critical Control Point (HACCP) system to the production of dressing. The hazard analysis examined the main materials, industrial water, microbial evaluation, and airborne microorganisms of each working area, as well as the pathogenic microbial contamination risk. The survey was conducted at SJ Company in Jincheon (Chungchengbuk-do), Korea for 30 days from April 1, 2012 to April 30, 2012. The results showed that raw material microorganisms had a total plate count in industrial water below $3.00{\times}10$ CFU/mL in working room I, working room II, the packing room, washing water, and the inspection room for five times in each place. During dressing production (including heat treatment and mixing), general bacteria were detected at an average of $3{\times}10$ CFU/mL, but yeast, mold, and pathogenic bacteria were not detected. Airborne microbiological evaluation (for total plate count, yeast, and mold) found levels below the legal limit at each working area. While workers were positive for microbes in total plate counts, coliform and Staphylococcus aureus were not detected. In conclusion, standards for hygienic management should be established to prevent and decrease hazards, such as general bacteria and pathogenic microorganisms (for example, E. coli, B. cereus, Listeria spp, Salmonella spp, Staph. aureus, Clostridium perfringens, yeast, and mold), and to found critical limits for microorganisms with an HACCP system.

• Journal of Environmental Health Sciences
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• v.19 no.1
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• pp.30-36
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• 1993

A survey was conducted to measure concentration of airborne microbe in a hospital using RSC air sampler during October~November 1991.The result was as follows: 1) In an agar strip GK-A media for total counts of microbial particles. The highest count were 1384 CFU/m$^3$ in the main lobby, followed by 912 CFU/m$^3$, in the obstetric room, 688 CFU/m$^3$ in 1CU. By gram staining, the distribution for organisms in the air were shown 74.1% in gram possitive cocci followed by 16.8%, in gram possitive bacilli 6.7% in gram negative bacilli and 4.7% in yeast, but low organism was detected in recovery room with 194 CFU/m$^3$. 2) In agar strip S media for Staphylococci the count at the main lobby was detected in the recovery room with 92 CFU/m$^3$, Tests of coagulase were negative Staphylococci with 78%, and positive Staphylococci with 22%. The Staphylococci were highly resistance to penicillin, ampicillin and sensitive to amikacin, cefazolin, gentamycin and chloramphenicol. 3) In agar strip C media for coliform bacteria the colony counts at the main lobby was 139 CFU/m$^3$ and treatment room was 190 CFU/m$^3$, most frequently isolated microorganisms were non fermentative bacilli. 4) In agar strip HS media for yeast and molds. Most frequently colony counts 17~76 CFU/m$^3$, 0.5% lactophenol cotton blue stains were shown unidentified 77.2%, 8.1%, in Penicillium 8.1% in Aspergillus, and 3.8% in mucor.

• Journal of Environmental Health Sciences
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• v.39 no.5
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• pp.456-464
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• 2013

Objectives: The aim of this study was to investigate the microbial contamination levels in elevators in apartment buildings and to provide information on such microbial contamination. Methods: A total of 144 samples, including from the exterior buttons, interior buttons, elevator handrails, walls, ventilators and airborne bacteria were collected in the morning and afternoon from July to August 2013 for six different elevators. The samples were used to detect sanitary indicator bacteria (total bacteria, coliform, and Escherichia coli), pathogenic bacteria (E. coli O157, L. monocytogenes, Salmonella spp., B. cereus, S. aureus) and fungi. Results: Contamination levels of total bacteria were 0.3-3.8 and 0.0-2.4 log CFU/100 $cm^2$ in the morning and afternoon, respectively. In the case of coliform bacteria, the levels were 0.0-3.7 log CFU/100 $cm^2$ in the morning and 0.0-0.3 log CFU/100 $cm^2$ in the afternoon. However, E. coli was not detected among all samples. Bacillus cereus, pathogenic bacteria, was only detected in 13 (11%) among 144 samples. E. coli O157, L. monocytogenes, Salmonella spp. and S. aureus were not detected among all samples. Comparing the samples collected in the morning and afternoon, we could confirm that the samples in the afternoon were cleaner. Conclusions: This study indicates that the samples in the afternoon were cleaner because these samples were collected following routine cleaning. Also, the levels of contamination in the elevators were low and the sanitary conditions were comparatively well-managed. Therefore it is deemed necessary for elevators be cleaned regularly to provide good conditions for people using elevators.

• Journal of Environmental Health Sciences
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• v.36 no.4
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• pp.306-312
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• 2010

This field study was performed to evaluate the efficiency of a plasma ion-operated air cleaner in temporal reduction of airborne pollutants emitted from a pig housing facility. In the case of gaseous pollutants, the plasma ion air cleaner was not effective in reducing levels of ammonia, hydrogen sulfide, nitrogen dioxide, or sulfur dioxide (p>0.05). In the case of particulate pollutants, however, the air cleaner was effective in reducing levels of particulate matter ($PM_{2.5}$ and $PM_1$) by 79(${\pm}6.1$) and 78(${\pm}3.0$)%, respectively. Unlike the case of these fine particle fractions, the reduction of total suspended particles (TSP) and $PM_{10}$ following treatment was almost negligible. In the case of biological pollutants, the mean reduction efficiencies for airborne bacteria and fungi were relatively low at 22(${\pm}6.6$) and 25(${\pm}8.7$)%, respectively. Taken together, these results indicate that in terms of air pollutants released from this pig housing facility, the plasma ion air cleaner was primarily effective in reducing levels of $PM_{2.5}$ and $PM_1$.