The objective of this study is to quantify the levels of airborne bacteria in pig building according to pig housing type. Mean concentration of airborne bacteria in the housing room of gestation/farrowing pigs were 3,690(±1,528)cfu m-3 in spring, 10,145(±4,266)cfu m-3 in summer, 1,546(±835)cfu m-3 in autumn, and 2,582(±916)cfu m-3 in winter, respectively. Mean concentrations of airborne bacteria in the housing room of nursery pigs were 11,628(±5,624)cfu m-3 in spring, 36,054(±13,260)cfu m-3 in summer, 2,743(±1,688)cfu m-3 in autumn, and 4,075(±2,300)cfu m-3 in winter, respectively. Mean concentrations of airborne bacteria in the housing room of growing/fattening pigs were 34,025(±8,652)cfu m-3 in spring, 36,619(±10,234)cfu m-3 in summer, 10,230(±3,521)cfu m-3 in autumn, and 26,208(±5,248)cfu m-3 in winter, respectively. As a result, mean concentrations of airborne bacteria in terms of pig housing type were highest in growing/fattening housing room followed by nursery housing room and gestation/farrowing housing room (p<0.05). The pig building showed the highest levels of airborne bacteria in summer followed by spring, winter and autumn (p>0.05). Overall airborne bacteria which have particle size over 2.1㎛ (stage 1~stage 4) accounted for approximately 80% compared to total airborne bacteria regardless of pig housing type. The predominant airborne bacteria in pig building were Micrococcus spp., Brevibacillus spp. and G(+) Bacillus.
In order to enhance the selective adsorption of CO2, the surface of granular activated carbon (GAC) was modified by an ammonia solution. Ammonia in an aqueous phase could be decomposed into NH4+, OH- and other N-containing elements. The present work attempted to impregnate some basic functional groups leading to chemisorption of the activated carbon surface. While the addition of N-groups reduced the specific surface area from 2071.4 m2/g to about 1300-1400 m2/g, the adsorption capacity for CO2 increased to a certain degree, and the best amination could be achieved with the reaction at 100℃ for 12 hours. The enhanced adsorption capacity could be obtained by formation of nitrogen functionalities such as amine, pyrrolic groups and pyridine oxides which were verified by XPS analysis.
The purpose of this study was to investigate the health risk and management of childhood exposure to indoor aldehydes in elementary-schools and academies. The samples were collected at children's facilities (50 elementary-schools and 46 academies) in summer (Aug ~ Sept, 2008), winter (Dec 2008 ~ Feb, 2009) and Spring (Mar ~ Apr, 2009) periods. The overall mean concentration of formaldehyde was 68.3 ㎍ /m3 and 27.2% of exceeded the 100 ㎍/m3 by the school health guideline. The concentration ratio of Indoor air and outdoor air (I/O) of aldehydes exceeds 1.0. The level of indoor air contamination did appear to be high, and 24.6% of the academies evaluated had exceeded the formaldehyde level specified by the public health act (120㎍ /m3). We estimated the lifetime excess cancer risks (ECRs) of formaldehyde, and the hazard quotients (HQs) of non-carcinogens (acetaldehyde and benzaldehyde). In addition, for carcinogens, the excess cancer risk (ECR) was calculated by considering the process of deciding cancer potency factor (CPF) and age dependent adjust Factor (ADAF) of the data of adults. The average ECRs of formaldehyde for young children were 1×10-6~1×10-5 level in all facilities. HQs of formaldehyde did exceed 0.1 for all subjects in elementary school.
This study was performed to investigate the exposure levels of magnetic field (MF) in residences near electrical transformer rooms in apartment buildings in Korea. We determined that the location of transformer rooms in apartment buildings in Korea is not same as in other countries. In particular, in Korea, the transformer on the pole near buildings serves residential buildings of less than 5 floors. In the buildings taller than 5 floors transformers are often placed below the parking lots in the basement. We estimated that there were, however, about 85,000 with transformer room adjacent to an apartment and had identified about 1,600 apartment buildings with transformers that can be included in the TransExpos study. The mean value of measured MFs was 1.17 mG in apartments above transformer room and 0.97 mG in other floors from transformer room. This study was concluded that apartments in building with transformer room can be classified into high-exposure category based on their location in relation to transformer room.
This case study carried out to improve the situation of large gap between scientific evidence and public perception on Extremely Low Frequency-Electric and Magnetic Fields (ELF-EMFs) problems in Korea. According to literature review on techniques and applications for EMF risk communication (RC) in Korea and other countries, the program which is appropriate for Korean society for RC was developed and the questionnaire to survey on perceptional level on ELF-EMFs based on this program was also developed. As some results of survey the perceptional levels on ELF-EMFs problems from some primary-school students and adults according to the educational tools (a presentation, a brochure, and a VOD) and protocols which were developed for RC, we identified in this study that the educational programs for RC have some effects to supply the right information and to improve the perceptional level on ELF-EMF problems to the general population such as the primary-school students and adults in Korea.
Exposure to environmental tobacco smoke (ETS) could adversely affect health. The aim of this study was to quantify the contribution of ETS exposure in nonsmokers of entertainment facilities. We simultaneously measured nicotine and nitrogen dioxide (NO2), which are known as indicators of ETS, concentrations in indoor internet cafe, billiard, karaoke, bar and restaurant, and estimated exposure level of other harmful agents occurred from tobacco smoking. Mean nicotine concentration (10.57±2.53㎍ /m3 ) of internet cafe was the highest comparing to other facilities, whereas mean concentration of restaurant where was non-smoking area was 0.28±0.08㎍ /m3 . There was statistically not correlated between NO2 and nicotine concentrations in entertainment facilities. Therefore, the use of NO2 concentration as indicator of ETS exposure may not be available. To date, there are no standards about each agent occurred from ETS. Consequently administrative control and regulation, and further researches in relation to ETS exposure should be needed.
In this study, amenity evaluation technique for indoor air quality in the underground space was developed and evaluated real-time amenity by utilizing real-time sensor monitoring system equipped with the technique. The factors used for amenity evaluation were PMV value, VOCs, illumination, PM10 and CO2. The amenity value with 60 percent represents the environmental standards of subjected factors. Based on the field survey using the monitoring system developed under this study, the amenity values of CO2 whose environmental standard is 1,000ppm were 97% for 400ppm and 26% for 1,100ppm, respectively. That of PM10 having 150㎍/㎥ as an environmental standard were 99% for 25㎍/㎥ and 80% for 100㎍/㎥. Evaluated amenity based on VOCs concentration at the subjected areas was in bad condition. And those for PM10 and CO2 were dependant on the floating population. From the results of this study, the real-time sensor monitoring system installed with the amenity evaluation technique could be a practical tool to evaluate indoor air quality to manage air quality of underground spaces like subway station. New amenity assessment technique using a real-time sensor monitoring of indoor air quality as well as physical environmental properties was developed in this study. The concentrations of CO2, PM10, VOCs were considered as new parameters to analyze the indoor air quality and they are included in an amenity assessment program of indoor area. We found that the new method is better to express the amenity degree of residents through field tests than conventional thermal comfort technique.