To evaluate the indoor air quality of food manufacturing plants, the presence of viable bacteria and fungi was assessed in the indoor air of the facilities at which 9 food items were manufactured. Air samples were collected from the general zone, low clean zone and clean zone of each factory with an air sampler, in combination with plate counts agar using for bacteria, and dichloran-glycerol agar for fungi. The samples were incubated at 25℃for 4 to 7 days. After culture, the colony forming units (CFU) on each plate were counted and corrected with a positive hole conversion table. The average concentration of bacteria was 2.2 × 10³ CFU/㎥ in the general zone, 1.2 ×10³ CFU/㎥ in the low clean zone and 7.3 × 10² CFU/㎥ in the clean zone. The average concentration of fungal microbes was 2.5 × 10³ CFU/㎥ in the general zone, 2.6 × 10³ CFU/㎥ in the low clean zone, and 2.0 × 10² CFU/㎥in the clean zone. No meaningful differences were detected between the general zone and the low clean zone, but the clean zone had significantly lower concentrations than the other zones. Additionally, the identification of the fungi was performed according to morphological method using a giant culture and slide culture. The fungi were identified as belonging to 18 genera, and the genera Cladosporium(33%), Penicillium(29%) and Aspergillus(26%), predominated. Aspergillus isolates were identified to species level, and A. ochraceus, a mycotoxigenic species, was identified. As part of the effort to control the quality of the indoor air of food manufacturing plants, our results show that continued studies are clearly warranted.

After infection by Gram negative bacteria, neonatal patients or patients in intensive care unit usually suffer from endotoxin shock, leading to death finally in spite of eradication of bacteria by potent antibiotics. The purpose of this study that is the pilot study to prevent endotoxin shock and nosocomial infection, is to offer basic data on species and concentrations of airborne microbes in hospitals. Therefore, this study collected and analyzed articles and documents on airborne microbes in hospitals in Korea that were published in relevant journals from 1980 to 2004. Studies on the concentration of airborne microbes in hospitals as a part of study on the nosocomial infection have been performed from the latter half of 1970s. Pooled average concentrations of total suspended bacteria in hospitals by RCS air sampler and Cascade air sampler were 194.85 CFU/㎥ and 367.72 CFU/㎥, respectively. They were lower than the guideline concentration(800 CFU/ ㎥) of the Korean Ministry of Environment. Pooled average concentrations of total suspended fungi in hospitals by RCS air sampler and Cascade air sampler were 20.66 CFU/㎥ and 193.34 CFU/㎥, respectively. They were lower than the guideline concentration(150 CFU/㎥) of the World Health Organization(WHO). Pooled average concentrations of total suspended bacteria in operating room and intensive care unit(ICU) were 324.75 CFU/㎥ and 182.43 CFU/㎥, respectively. They again were lower than the guideline concentration of the Korean Ministry of Environment. Staphylococcus spp., Micrococcus spp., and Lactobacillus spp. for Gram-positive bacteria, and Pseudomonas spp., Klebsiella spp., and Escherichia spp., for Gram-negative bacteria were shown in hospitals. Also, Aspergillus spp., Penicillium spp., Mucor spp., Epidemophyton spp., Trichophyton spp., and Cladosporium spp. for fungi were found in hospitals. Staphylococcus spp. was shown frequently in operating rooms, intensive care units and wards. Penicillium spp. and Aspergillus spp. were shown commonly in them.