• Clinical and Experimental Pediatrics
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• 제51권2호
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• pp.181-187
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• 2008

목 적 : 천식의 특징은 기도염증의 결과인 가역적인 기류제한과 기관지과반응성이다. 최근에 호기산화질소(exhaled nitric oxide; FeNO)이 비침습적으로 기도염증을 알 수 있는 지표로서 이에 대한 많은 연구가 있었다. 또한 FeNO는 천식의 중증도를 나타내는 데 이용되는 객담내 호산구수나 메타콜린 기도유발시험과 관련이 있다고 보고되었다. 이에 저자들은 간헐성 천식환자에서 폐기능검사와 호기산화질소와의 관계를 알아보고자 본 연구를 시행하였다. 방 법 : 2005년 4월부터 8월까지 경희의대부속병원 소아과에서 천식으로 진단되어 폐기능검사와 호기산화질소 측정이 가능하였던 5세부터 15세의 80명의 환자를 대상으로 하였다. 최근 4주내에 상기도 감염이 없었고, 부신피질스테로이드를 포함한 조절약물을 사용하지 않은 경우에 연구 대상에 포함하였다. 폐기능검사는 Microspirometer를 사용하였다. Eco Medics사의 Chemiluminescence NO-analyzer(CLD 88 sp, Duernten, Switzerland)를 사용하여 FeNO를 측정하였으며 폐기능 검사와 FeNO와의 상관관계 분석은 Spearman correlation coefficient를 사용 하였다. 결 과 : 1초간 강제호기량(forced expiratory volume in 1 second, $FEV_1$)의 평균은 $0.890{\pm}0.455L$이었으며 강제폐활량 (forced vital capacity; FVC)의 평균은 $1.071{\pm}0.630L$이었다. $FEV_1%pred$의 평균은 $98.39{\pm}34.27%$였으며 $FEV_1/FVC$의 평균은 $88.53{\pm}19.49$이었다. FeNO의 평균치는 16.88 parts per billion(ppb)이었다. FeNO 측정치는 $FEV_1$(r=0.345, P<0.01), FVC(r=0.244, P<0.05)와 유의한 상관관계를 보였으나 $FEV_1%pred$와 $FEV_1/FVC$는 FeNO와 유의한 상관관계를 나타내지 않았다. 결 론 : FeNO의 측정은 폐기능 검사와 함께 소아천식 환자의 관리에 유용하게 사용될 수 있는 신빙성있는 검사로 생각되며 측정 방법이나 측정치의 참고치 설정에 앞으로 많은 연구가 필요할 것으로 생각된다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권4호
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• pp.2461-2476
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• 2013

To assess environmental contamination with carcinogens, carbonaceous compounds, water-soluble ionic species and trace gaseous species were identified and quantified every three hours for three days st three different atmospheric layer at the heart of chiang-Mai, bangkok and hat-Yai from December 2006 to February 2007. A DRI model 2001 Themal/Optical Carbon Analyzer with the IMPROVE thermal/optical reflectance (TOR) protocol was used to quantify the organic carbon(OC) and elemental carbon content in $PM_{10}$. Diurnal and vertical variability was also carefully investigated. In general, OC and EC contenttration shoeed the highest values at the monitoring period o 21.00-00.00 as consequences of human activities at night bazaar coupled with reduction of mixing layer, decreased wind speed and termination of photolysis nighttime. Morning peaks of carboaceous compounds were observed during the sampling period of 06:00 -09:00, emphasizing the main contribution of traffic emission in the three cities. The estimation of incremental lifetime partculate matter exposure (ILPE) raises concern of high risk of carbonaceous accumulation over workers and residents living close to the observatory sites. The average values of incremental lifrtime particulate matter exposure (ILPE) of total carbon at Baiyoke Suit Hotel and Baiyoke Sky Hotel are approsimately ten time shigher then those air sample collected at prince of songkla University Hat-Yai campus corpse incinerator and fish-can maufacturing factory but only slightly higher than those of rice straw burnig in Songkla province. This indicates a high risk of developing lung cancer and other respiratory diseases across workers and residents living in high buildings located in Pratunam area. Using knowledge of carbonaceous fractions in $PM_{10}$, one can estimate the gas-particle partitioning of polycyclic aromatic hydrocarbons (PAHs). Dachs-Eisenreich model highlights the crucial role of adsorption in gas-particle partitioning of low molecular weight PAHs, whereas both absorption and adsorption tend to account for gas-particle partitioning of high molecular weight PAHs in urban residential zones of Thailand. Interestingly, the absorption mode alone plays a minor role in gas-partcle partitiining of PAHs in Chiang-Mai, Bangkok and hat-Yai.

• Journal of the Korean Data and Information Science Society
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• 제26권6호
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• pp.1409-1416
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• 2015

기온의 변화는 인간의 건강뿐 아니라 동식물의 성장, 경제, 사회, 산업, 문화 등의 전 분야에 영향을 준다. 본 연구에서는 수원시 2003년-2012년 기온을 기상자료, 온실가스자료, 대기자료를 이용하여 자기회귀오차 (autoregressive error)모형으로 월별로 분석하였다. 기온을 위한 기상자료로는, 풍속, 강수량, 일사량, 운량, 습도를 사용했고, 온실가스자료는 이산화탄소 ($CO_2$), 메탄 ($CH_4$), 아산화질소 ($N_2O$), 염화불화탄소 ($CFC_{11}$), 대기자료는 미세먼지 ($PM_{10}$), 이산화황 ($SO_2$), 이산화질 소 ($NO_2$), 오존 ($O_3$), 일산화탄소 (CO)을 사용하였다. 기온을 월별 분석한 결과 기상변수로는 일사량, 운량, 풍속이 영향을 많이 주는 것으로 분석되었다. 특히 일사량은 봄, 여름, 가을에 영향을 많이 주고 풍속은 겨울에 영향을 많이 주는 것으로 나타났다. 온실가스변수로는 염화불화탄소와 메탄이 기온에 영향을 많이 주고 대기변수로는 오존이 영향을 많이 주는 것으로 타났다. 자기회귀오차모형으로 월별 기온을 43%~69% 정도 설명할 수 있다.

• Bulletin of the Korean Chemical Society
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• 제35권4호
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• pp.1149-1153
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• 2014

Real-time monitoring of hourly atmospheric radon (Rn-222) concentration was performed throughout 2011 at Gosan station, Jeju Island, one of the least polluted regions in Korea, in order to characterize the background levels, and temporal variations on diurnal to seasonal time-scales. The annual mean radon concentration for 2011 was $2527{\pm}1356$ mBq $m^{-3}$, and the seasonal cycle was characterized by a broad winter maximum, and narrow summer minimum. Mean monthly radon concentrations, in descending order of magnitude, were Oct > Sep > Feb > Nov > Jan > Dec > Mar > Aug > Apr > Jun > May > Jul. The maximum monthly mean value (3595 mBq $m^{-3}$, October), exceeded the minimum value (1243 mBq $m^{-3}$, July), by almost a factor of three. Diurnal composite hourly concentrations increased throughout the night to reach their maximum (2956 mBq $m^{-3}$) at around 7 a.m., after which they decreased to their minimum value (2259 mBq $m^{-3}$) at around 3 p.m. Back trajectory analyses indicated that the highest radon events typically exhibited long-term continental fetch over Asia before arriving at Jeju. In contrast, low radon events were generally correlated with air mass fetch over the North Pacific Ocean. Radon concentrations typical of predominantly continental, and predominantly oceanic fetch, differed by a factor of 3.8.

• 한국산업보건학회지
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• 제27권1호
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• pp.38-45
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• 2017

Objectives: Radon may be second only to smoking as a cause of lung cancer. Radon is a colorless, tasteless radioactive gas that is formed via the radioactive decay of radium. Therefore, radon levels can build up based on the amount of radium contained in construction materials such as phospho-gypsum board or when ventilation rates are low. This study provides our findings from evaluation of radon gas at facilities and offices in an industrial complex. Methods: We evaluated the office rooms and processes of 12 manufacturing factories from May 14, 2014 to September 23, 2014. Short-term data were measured by using real-time monitoring detectors(Model 1030, Sun Nuclear Co., USA) indoors in the office buildings. The radon measurements were recorded at 30-minute intervals over approximately 48 hours. The limit of detection of this instrument is $3.7Bq/m^3$. Also, long-term data were measured by using ${\alpha}-track$ radon detectors(${\alpha}-track$, Rn-tech Co., Korea) in the office and factory buildings. Our detectors were exposed for over 90 days, resulting in a minimum detectable concentration of $7.4Bq/m^3$. Detectors were placed 150-220 cm above the floor. Results: Radon concentrations averaged $20.6{\pm}17.0Bq/m^3$($3.7-115.8Bq/m^3$) in the overall area. The monthly mean concentration of radon by building materials were in the order of gypsum>concrete>cement. Radon concentrations were measured using ${\alpha}-track$ in parallel with direct-reading radon detectors and the two metric methods for radon monitoring were compared. A t-test for the two sampling methods showed that there is no difference between the average radon concentrations(p<0.05). Most of the office buildings did not have central air-conditioning, but several rooms had window- or ceiling-mounted units. Employees could also open windows. The first, second and third floors were used mainly for office work. Conclusions: Radon levels measured during this assessment in the office rooms of buildings and processes in factories were well below the ICRP reference level of $1,000Bq/m^3$ for workplaces and also below the lower USEPA residential guideline of $148Bq/m^3$. The range of indoor annual effective dose due to radon exposure for workers working in the office and factory buildings was 0.01 to 1.45 mSv/yr. Construction materials such as phospho-gypsum board, concrete and cement were the main emission sources for workers' exposure.

• 전자공학회논문지SC
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• 제39권6호
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• pp.42-48
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• 2002

다목적 방사선 조사장치의 설계, 제작 및 성능검사에 대해 기술하였다. 세슘-137을 사용한 다목적 방사선조사장치는 생물학에서 저선량 방사선에 대한 영향연구, 혹은 TLD(Thermo Luminescent dosimeter)의 교정을 위해 사용되어진다. 본 조사장치는 방사선 동위원소를 안전한곳에 저장하고 있다가 방사선조사시에만 조사실로 180도 회전하여 설정된 시간만큼 시료에 방사선 조사가 이루어 진 후, 사용이 끝나면 다시 차폐된 저장위치로 복귀하게된다. 제어시스템은 PLC 기반으로 구축하여 저선량율 조사장치의 시제품을 제작하였으며, 또한 컴퓨터를 통해 방사선 조사장치의 제어 및 세부 동작 상태 등을 실시간 검색, 원격제어 및 관리 할 수 있는 종합 관리 프로그램을 개발하였다. 조사실 내부 구성은 시료의 종류에 따라 최대 20RPM까지 다양하게 회전하면서 균일 조사될 수 있도록 조사실 및 챔버를 설계 제작하였으며, 조사실내 넣을 수 있는 조사체 최대 용량은 4.5리터이다. 조사실내의 방사선량의 분포도는 가프크로믹 필름을 사용하여 측정한 결과 2Ci 범위내에서 세슘-137의 경우 공기중에서 0.13cGy/min이었고 일반 물질과 등가인 물에서는 0.11cGy/min로 나타났으며, 오차는 약 ${\pm}$7%의 한도내에서 균일한 분포를 보였다. 또한 실제 누설선량은 조사실 밖 표면에서 최대 0.35mR/hr이였으며 1m 떨어진곳에서는 최대 0.03mR/hr로 허용치 이내였다.

• 한국환경농학회지
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• 제40권4호
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• pp.330-334
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• 2021

BACKGROUND: More recently, it has been shown that atmospheric ammonia (NH₃) plays a primary role in the formation of secondary particulate matter by reacting with the acidic species, e.g. SO₂, NOx, to form PM2.5 aerosols in the atmosphere. The Jeonbuk region is an area with high concentration of particulate matter. Due to environmental changes in the Saemangeum reclaimed land with an area of 219 km², it is necessary to evaluate the impact of the particulate matter and atmospheric ammonia in the Jeonbuk region. METHODS AND RESULTS: Atmospheric ammonia concentrations were measured from June 2020 to May 2021 using a passive sampler and CRDS analyzer. Seasonal and annual atmospheric ammonia concentration measured using passive sampler was significantly lower in Jangjado (background concentration), and the concentration ranged from 11.4 ㎍/m³ to 18.2 ㎍/m³. Atmospheric ammonia concentrations in Buan, Gimje, Gunsan, and Wanju regions did not show a significant difference, although there was a slight seasonal difference. The maximum atmospheric ammonia concentration measured using the CRDS analyzer installed in the IAMS near the Saemangeum reclaimed land was 51.5 ㎍/m³ in autumn, 48.0 ㎍/m³ in summer, 37.6 ㎍/m³ in winter, and 32.7 ㎍/m³ in spring. The minimum concentration was 4.9 ㎍/m³ in spring, 4.2 ㎍/m³ in summer, and 3.5 ㎍/m³ in autumn and winter. The annual average concentration was 14.6 ㎍/m³. CONCLUSION(S): Long term monitoring of atmospheric ammonia in agricultural areas is required to evaluate the formation of fine particulate matter and its impact on the environment. In addition, continuous technology development is needed to reduce ammonia emitted from farmland.

• 한국산업보건학회지
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• 제11권1호
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• pp.34-41
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• 2001

Passive samplers have been used for personal, indoor, and outdoor air monitoring of VOCs at ppb concentrations in community and office environments. The path length of modified passive sampler was shortened, so it was intended to increase an uptake rate. The performance of the modified 3M 3500 organic vapor monitor(OVM) as a tool for assessing exposures to toxic air pollutants in nonoccupational community environments was evaluated using combined controlled test atmospheres of six selected target volatile organic compounds(VOCs): benzene, methyl tert-butyl ether(MTBE), chloroform, 1,4-dichlorobenzene, tetrachloroethylene, and toluene. The experiments were conducted by exposing the dosimeters to concentrations of $50{\sim}100{\mu}g/m^3$ on six face velocity(0.00, 0.02, 0.06, 0.12, 0.20, 0.30 m/sec) for 24 hours. If the uptake rate was increased, that means that we could use the passive sampler more effectively. The uptake rates were increased linearly according to reduce the path length. Although the diffusion path length was shortened, the change of uptake rate was within ${\pm}25%$ of theoretical value, indicating that the modified passive sampler(TM) can be effectively used over the range of concentrations and environmental conditions tested with a 24-h sampling period if the face velocities were over 0.12 m/s for 6 components of VOCs. But when the face velocities were less than 0.12 m/s, uptake rates were reduced more than expected values. So, the passive sampler with the shortened path length should be used at indoor or outdoor environment where the face velocity should be over about 0.10 m/s. If the path length was shortened more, the uptake rate was more effected by starvation.

• 한국대기환경학회지
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• 제22권5호
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• pp.642-652
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• 2006

In order to understand the characteristics of surface ozone concentration and high $O_3$ concentration days, regional data from seven air quality monitoring stations which were operated by local governments were analyzed Regional characteristics of $O_3$ concentration were analyzed with the data of $O_3$ concentration and the characteristics of $O_3$ generation and weather conditions by the selection of the days in which the concentration was higher than 80 ppb. In the case of daily variation, the lowest $O_3$ concentration was shown in all regions from 7am to 8am and the highest around at 4 pm. The monthly variation of mean $O_3$ concentration and ${\Delta}O_3$ values revealed a reducing pattern in July and August following the peak in June, and again a gradual increasing trend in September and October. The result shows that the amount of ozone is dependent on photochemical reaction. The days of $O_3$ generated more than 80 ppb in the region of Gwangyang-bay were 544 days(1,760 hrs). The frequency of occurrence in the region revealed a strong pattern with the order of Samil-dong, Jinsang, and Gwangmu-dong stations in the Gwangyang region. However, Tein-dong, which is the nearest station to air pollution material generation source, showed the lowest frequency in the study area. Consequently, the meteorological parameters which can easily generate the high concentration of $O_3$ in the region of Gwangyang-bay are characterized as follows; atmospheric temperature which is higher than $19^{\circ}C$, relative humidity with the range of $60{\sim}85%$, the less average wind velocity than 5 m/s, cloud cover which is less than 5/10, and the more duration of sunshine than 8 hours.

• 한국산림과학회지
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• 제84권4호
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• pp.424-431
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• 1995

이 연구는 open-top chamber내에서 오존 가스에 폭로시킨 느티나무(Zelkova serrata Makino)의 저항성과 생리적 반응을 구명하기 위하여 수행되었다. 화분에 심어 4월에서 8월까지 온실에서 키운 1년생 느티나무 묘목을 야외에 설치한 두개의 open-top chamber(직경2m, 높이2m)에 70본씩 나누어 넣은 후, 한 chamber는 오존 가스 처리구로, 다른 chamber는 대조구로 실험에 이용하였다. 오존 가스 처리구에는 하루 5시간씩(10.00 AM-15.00 PM) 23일 간 0.1ppm 농도의 오존을 폭로하였으며, 대조구는 일반 대기에 노출시켰다. 오존 가스에 폭로 후 2일, 3일, 혹은 5일마다 각 chamber에서 10본씩의 묘목을 임의로 꺼내어 엽록소 a, b의 양, 총엽록소의 양, ${\beta}$-카로틴의 함량을 측정하였다. 광합성량은 가스교환 chamber 내에서 이산화탄소 흡수량으로 측정하였으며, 호흡량은 암흑에서 산소 흡수량으로 측정하였고, SOD(superoxide dismutase)는 xanthine oxidase방법으로 측정하였다. 오존 폭로 14일 후에 물에 젖은 듯한 반점의 가시적 피해가 나타나기 시작하였으며, 오존 가스는 성엽의 노화를 촉진시켰다. 오존에 폭로시킨 지 이틀 후에 엽록소 a, b의 양은 각각 17%, 31% 감소하였으며, 엽록소 b의 감소 속도가 엽록소 a의 감소 속도보다 빨랐다. ${\beta}$-카로틴은 오존에 폭로시킨 지 이틀 후에 25%가 감소하였으나, 시간이 지남에 따라 회복되는 것으로 나타났다. 광합성 능력은 오존 처리구에서 45% 감소하였고, 호흡량은 28% 증가하였다. SOD활성은 오존 폭로 4일 후부터 증가하여 7일 만에 대조구의 285%에 도달하였다가 이후 다시 감소하여 가시적 피해가 나타나는 시기부터 대조구보다 더 낮은 활성을 보였다. 느티나무 묘목은 오존에 의하여 비교적 민감하게 피해를 받으며, SOD 활성은 오존 폭로에 대하여 초기 방어기작으로 나타나는 생리적 지표라고 결론 짓는다.