This study measured concentrations of formaldehyde, a pollutant in the indoor air in three departments, before and after the renovation of a medical facility used by the general public, and conducted a health survey on workers' subjective symptoms. The average concentration of formaldehyde was 25.8 ± 8.7 μg/m3 before the renovation and 47.3 ± 6.7 μg/m3 after the renovation. The concentration was increased; however, it did not exceed the maintenance standard set by the law. Measured concentration was high both before and after the renovation in the office, and the biggest difference was shown in the concentration change. For eight symptoms including dry throat, there were more workers who expressed the symptoms after the renovation than those who expressed them before the renovation. Factors that influenced subjective symptoms were the effects before and after the renovation. Even when formaldehyde does not exceed the maintenance standard set by the law, detailed and systematic management is required and adequate health effect evaluation or education is necessary, considering the characteristics of medical facilities.

This study aims to analyze the effects of 4 directions of wind, wind speed, year of construction of slate roofs, installation area and other factors on the concentration and size distribution of airborne fiber particles in farmhouses with a slate roof containing asbestos. Airborne fiber particle samples were collected from the air in six houses with a slate roof containing asbestos using a high flow rate pump (10 L/min) for 2 hours, three times a day with a different condition, 72 times in total. The airborne fiber particle concentrations were measured using a phase contrast microscope, and the size of fiber particles of 72 samples in total was estimated using the mean value of those in each sample measured at 100 with a field of view. The total average concentration of fiber particles collected from in the air in four directions of the targeted farmhouses was 2.83 fiber/L, and its maximum concentration was 5.75 fiber/L, which means that among all samples there was no place that exceeded 10 fiber/L, a recommended indoor air quality standard. The average size of the fiber particles was 11.55 μm, and the maximum size was 40 μm. A multiple regression analysis of factors affecting the concentration and size of fiber particles in the air collected from the farmhouses with a slate roof containing asbestos found that the closer to the main wind direction (p<0.001) and the faster the average wind speed (p<0.05), the fiber particles concentration became significantly higher. In this case, the coefficient of determination was 52.8%. It was also found that the wider the total area of the slate roof (p<0.001) and the slower the average wind speed (p<0.05), the longer the fiber particles; the coefficient of determination for this finding was 19.6%. The concentration of fiber particles in the air of farmhouses with a slate roof appeared to be the highest under the main wind direction, and became significantly higher as the wind speed became faster. This proved that fiber particles were leaked from the slate roof. The size of the fiber particles became significantly longer as the area of the slate roof became wider and the wind speed became slower.

본 연구에서는 서울지역의 지상 미세먼지(PM2.5) 농도를 산출하기 위하여 경험적인 모델들을 개발하였다. 연구에 이용한 자료는 2012년 1월 1일부터 2013년 12월 31일까지이며 Terra와 Aqua위성의 MODIS센서에서 산출되는 에어로 졸 광학두께, 옹스트롬 지수, 기상변수들과 행성경계층두께와 관련된 6개의 다중 선형 회귀모델들의 차이를 분석하였다. 그 결과 에어로졸 광학두께와 옹스트롬 지수, 상대습도, 풍속, 풍향, 행성경계층두께, 기온 자료를 입력 자료로 사용한 M6모델이 가장 좋은 결과를 보였다. 통계적인 분석에 따르면 M6 모델을 사용하여 계산된 PM2.5와 관측된 PM2.5농도 사 이의 결과는 상관계수(R=0.62)와 평균제곱근오차(RMSE=10.70 μg m−3)이다. 또한 산출된 계절별 지표면 PM2.5농도는 여름철(R=0.38)과 겨울철(R=0.56)보다 봄(R=0.66)과 가을철(R=0.75)에 상대적으로 더 좋은 상관 관계를 보였다. 이러한 결과는 에어로졸 광학두께의 계절별 관측 특성으로 인한 것으로써 다른 계절에 비하여 여름과 겨울철 에어로졸 광학두께 관측이 구름과 눈/얼음 표면에 의한 관측 제한과 오차를 가져온 것으로 분석되었다. 따라서 본 연구에서 사용한 경 험적 다중선형회귀 모델은 위성에서 산출된 에어로졸 광학두께 자료가 지배적인 변수로 작용하며 PM2.5산출 결과들을 향상시키기 위해서는 추가적인 기상 변수를 이용해야 할 것이다. 또한 경험적 다중선형회귀 모델을 이용하여 PM2.5를 산출한 결과는 인공위성 자료로부터 대기환경 감시를 가능하게 하는 방법이 될 수 있어 유용할 것이다.

This study evaluated the antimicrobial efficacy of different concentrations of ozonated water with organic matter, fetal bovine serum, at different concentrations and incubation times with bacteria. In the absence of organic matter, total eradication of up to 5 log of Escherichia (E.) coli was achieved, however, interference by organic matter led to inefficiency of ozonated water as a disinfecting agent. In addition, diminishing antimicrobial effects at higher temperatures, even in the absence of organic matter, were also demonstrated. These findings indicate that ozonated water will be a safe and effective disinfectant agent that could be useful in meat processing, especially an intestine processing, in Korean slaughter houses.

Nitrite and nitrates are usually used in the production of meat products as food additives even though they pose a secondary risk. In this study, the residues of nitrite and nitrate ions in 366 processed meat products distributed in Seoul were analyzed using ion chromatographs and UV spectrophotometers. In all tested products, the residues of nitrite were below 70 mg/kg, which met the processing standard and component specification for livestock products. Evaluation of nitrite ions, revealed a mean concentration of 7.1 - 11.9 mg/kg in hams, sausages, and bacons, while higher ratios of nitrite were found in other types of products. Among the studied processed meat products, at least 60% of hams and sausages had indications of nitrite, as did 90% of bacons and dry meats. No spiced meat and less than 10% of crushed meat had indications of nitrite. However, all dried meats showed below 1 mg/kg, regardless of whether they had indications of nitrite. Up to 9.7 mg/kg of nitrite was detected in the products with no indication of nitrite, and 14.6% of all products had at least 1 mg/kg of nitrite. This can be attributed to the reduction of residual nitrate ions in the products into nitrite ions. A review of the concentrations of nitrate ions in processed meat products by type suggests that the mean concentration was 22.3 (maximum 110.2) mg/kg in hams, 31.8 (maximum 89.5) mg/kg in sausages, 16.4 (maximum 28.2) mg/kg in bacons, 16.8 (maximum 61.1) mg/kg in spiced meats, 20.2 (maximum 99.4) mg/kg in crushed meats, and 121.0 (maximum 216.5) mg/kg in dried meats. Therefore, dried meats showed much higher nitrate ion concentrations than other types of meat products; however, the residue of nitrite ions in actual dried meats was found to be lower than 1 mg/kg, suggesting that the concentrations of nitrate ions do not affect those of nitrite ions. However, a certain concentration of nitrate ions was observed even when nitrate ions were not used in the products, as nitrite ions were transformed into nitrate ions and nitrite ions were detected even the products with no indication of nitrite ions. Therefore, continuous monitoring and preparation of relevant standards of the use of nitrate in processed meat products are necessary.

토마토를 저면관비 방법으로 육묘할 때 유묘 생장과 상토 무기원소 농도 변화에 적합한 추비의 종류 및 농도를 구명하기 위해 본 실험을 수행하였다. 육묘용 2종류의 동절기 혼합상토 피트모스 0-6mm(PM06)+perlite 1- 2mm(PE2)(7:3, v/v)와 피트모스 5-15mm(PM515)+PE2(7:3, v/v)를 72공 플러그 트레이에 각각 충전하고 토마토 ‘도태 랑다이아’ 종자를 파종하여 발아시킨 후 생장상에서 35 일간 육묘하였다. 자엽형성기에 추비를 시작하였고 13- 2-13, 15-0-15, 20-9-20(N-P2O5-K2O) 복합비료를 순서대로 처리하였다. 추비시 생육 단계별로 25mg·L-1의 농도 차(N 기준)를 둔 3종류의 Program을 두어 시비하였으며, 플러그 트레이의 수분이 포화 기준으로 40-50%로 감소 하였을 때 저면관비하였다. 파종 후 1, 2, 4 및 5주째 혼합상토를 상부, 중간, 하부로 3등분하여 포화추출한 후 추출용액의 pH, EC 및 무기이온 농도를 분석하고, 5주 후에 유묘생장을 조사하였다. 육묘 기간 중 상토의 pH는 PM06+PE2가 PM515+PE2 보다 높았으며, 하부와 중간이 상부보다 높은 경향이었다. EC는 PM06+PE2가 PM515+PE2보다 높았으며 평균적으로 상부가 하부보다 2배 이상 높았다. NH4-N과 K+ 농도는 2종류 혼합상토의 모든 시비 Program에서 육묘 후 5주까지 높아졌으며, PM06+PE2의 추비 프로그램 3에서 가장 높았다. NO3-N 농도는 PM06+PE2에서 육묘기간 동안 높아졌고 추비 농도가 높을수록 그러한 경향이 뚜렷하였다. 지상부 생 체중을 비롯한 유묘의 생장은 PM06+PE2의 추비 Program 2에서 가장 우수하였다. 따라서 2종류 혼합상토 를 이용한 공정육묘시 13-2-13, 15-0-15 및 20-9-20을 순서대로, 질소 기준 25mg·L-1에서 125mg·L-1까지 육묘 기에 따라 점차적으로 높여 추비하는 방법이 적합하다고 판단하였다.

2011-2015년 동안 한국 중부 태안과 청주 강내의 배경 관측지점에서 측정한 PM10, PM2.5 질량 농도를 분석하 였다. 황사 사례를 제외한 PM10 질량 농도의 계절변동에서 겨울-봄 동안 높은 농도는 서풍 기류에 의한 영향이 반영 되고 있으며, 여름에는 북태평양 기단과 잦은 강수로 낮은 수준을 보이고 있었다. 따라서, 일평균 PM10 질량 농도 81μg m-3 (미세먼지 예보 ‘약간 나쁨’ 이상) 이상의 사례도 겨울-봄 동안에 발생이 많으며, 특히 중국 동부 배출원에 가까 운 태안에서 더 많은 사례가 발생하고 있었다. 인위적으로 발생한 연무는 입경 2.5 μm 미만 입자의 구성 비율이 높다. 천리안 위성의 밝기온도차 분석에서 대기와 입자가 작은 연무는 −0.5 o K 이상에서 관측된다. 2011-2015년 동안 태안과 청주 강내에서 관측한 연무 사례일의 PM10 질량 농도와 NOAA 19 위성 밝기온도차를 분석하였다. PM10 질량 농도 는 200 μg m−3 보다 낮지만, PM2.5/PM10 질량 농도비는 0.4보다 높고 밝기온도차는 −0.3-0.5 o K 범위에 분포하고 있었 다. 그러나, PM10 질량 농도 190 μg m−3 이상인 황사 사례의 밝기온도차는 PM2.5/PM10 질량 농도비가 0.4보다 낮고, 밝기온도차는 −0.7 o K 이하의 범위에 분포하고 있었다. 이러한 연무의 밝기온도차 경계값 범위를 적용한 결과는 MODIS AOD, OMI AI의 에어로졸 분포 범위와 일치하였다.

The objective of this experiment was to evaluate the effect of Chamaecyparis obtus extract to reduce odor emissions released from the swine feeding operations. Finisher pigs [Landrace × (Yorkshire × Duroc)] with an initial body weight averaging 50 kg were housed separately in two rooms with eighty eight pigs in each room at a swine feeding operation site. C. obtus extract was sprayed in the room by ceiling sprayer for one minute at twice per day during two months. Concentrations of odorous compounds from air in the room of the swine feeding operation were analyzed at four times during two months. Levels of butyric acid, valeric acid, i-butyric acid, ivaleric acid, skatole, methylmercaptan, and trimethylamine tended to decrease in C. obtus extract spray treatment group compared to the non-spray treatment group (P > 0.05). Odor activity values of butyric acid, valeric acid, skatole and trimethylamine were higher than other odorous compounds and decreased by 72%, 76%, 54% and 20%, respectively, in C. obtus extract spray treatment group compared to the non-spray group. Taken together, C. obtus extract showed an odor reducing capability in the air of a swine feeding operation suggesting that it possesses anti-bacterial properties as well as having a dust removal and masking effect.

Radon (222Rn) gas is a main source of ionizing radiation of natural origin. It typically moves up through the ground to the air above and into building or home through cracks and other holes in the foundation. Significantly, the Surgeon General has warned that radon is the second leading cause of lung cancer in the United States today. This survey covers the determination of indoor radon concentrations at home from 2013 to 2014 in some areas of Gangwondo, every three months (seasonal) during one year using an alpha-track detector. The results showed that the annual average concentration of indoor radon was 84.5 Bq/m3 (GM: 64.5 Bq/m3) at homes. Indoor radon level was the highest in winter and the lowest in summer. Geometric mean radon concentration in winter was 1.03~2.58 times higher than other seasons. The data obtained from this study provide a basis for the preparation of legal regulation and public health protection manuals in this area.

Carbon source, an essential nutrient for plant growth, mainly includes exogenous sugar and CO2 of the environment in vitro. Therefore, the exogenous sugar and CO2 of the environment make the important roles in tissue culture. The aim of this study is to investigate the effects of different sugar concentrations (0, 10, 15 and 30 g·L-1) on the growth of colored Zantedeschia in vitro under certain CO2 concentration and explore the optimal sugar concentration. The plantlets in vitro of colored Zantedeschia had the largest root number, root weight, and root vigor under 0 g·L-1 (sugar-free culture) treatment. And they had the largest plant height, leaf length and leaf chlorophyll content, but p oor r oot v igor under 3 0 g·L-1 sugar. This study indicated that the optimal condition for proliferation and seedling culture of colored Zantedeschia plantlets in vitro was MS medium with 30 g·L-1 sugar, and the suitable medium for rooting culture and transplanting of colored Zantedeschia was MS medium with sugar-free culture under CO2 enrichment condition.

In this study, we investigated the concentrations of PM10 and CO2 in public transportation vehicles (express bus, train, KTX, and subway) reported by previous indoor air quality (IAQ) surveys carried out from 2005 to 2013 in Korea. The number of valid data for PM10 was 566 and for CO2 was 579, and all data were classified according to whether it was collected during rush-hour or non rush-hour. PM10 and CO2 concentrations in subway cabin during the rush-hour were 1.3 and 1.45 times higher, respectively, than those of non rush-hour (p<0.05) in terms of geometric mean value. PM10 and CO2 concentration of express bus and train during the rush-hour also were 1.23 times higher than those of non rush-hour with relatively weak correlations (p=0.246). Among all PM10 concentrations, 16.9% and 3.8% of PM10 concentrations exceeded the IAQ guidelines (200 μg/m3 for non-rush hour and 250 μg/m3 for rush-hour), respectively. In terms of CO2 concentrations, 10.5% and 3.0% of them exceeded the IAQ guidelines (2,500 ppm for non rush-hour and 3,000 ppm for rush-hour), respectively. As a result, concentrations of PM10 and CO2 were estimated to be dominantly influenced by the operation characteristics of public transportation, such as degree of congestion and type of vehicle. In order to improve the IAQ of public transportation vehicles, specific air purification and ventilation systems are needed, depending on the characteristics of public transportation vehicles.

The concern of fine particle (PM2.5) management of outdoor environments has been increasing due to its exposure and related health effects in Korea. As a result, PM2.5 standard in atmosphere environment was regulated in 2015. On the other hand, indoor PM2.5 standard has been required because most people spent their times in indoor environments. In this study, we measured the PM2.5 and PM10 concentrations both indoor and outdoor environments of public-use facilities such as underground stations, underground shopping centers, and nurseries for 24 hour with filter-weighing method in Seoul and Daegu. Measurement duration was from March to April in 2014 during the Asian dust period. At all measurements, indoor to outdoor (I/O) concentration ratios exceeded 1 except 1 day nursery in Daegu in spite of Asian dust period. The ratios of PM2.5 to PM10 concentrations ranged from 0.63 to 0.75 in indoor environments, and from 0.63 to 0.82 in outdoor, indicating that PM2.5 should be carefully managed in indoor environments as well as outdoor atmosphere.

Minimal inhibitory concentration (MIC) is the lowest antibiotic concentration that inhibits the visible growth of bacteria. Sub-minimal inhibitory concentration (Sub-MIC) is defined as the concentration of an antimicrobial agent that does not have an effect on bacterial growth but can alter bacterial biochemistry, thus reducing bacterial virulence. Many studies have confirmed that sub-MICs of antibiotics can inhibit bacterial virulence factors. However, most studies were focused on Gram-negative bacteria, while few studies on the effect of sub-MICs of antibiotics on Gram-positive bacteria. In this study, we examined the influence of sub-MICs of doxycycline, tetracycline, penicillin and amoxicillin on biofilm formation and coaggregation of Streptococcus gordonii, Streptococcus mutans, Actinomyces naeslundii, and Actinomyces odontolyticus. In this study, incubation with sub-MIC of antibiotics had no effect on the biofilm formation of S. gordonii and A. naeslundii. However, S. mutans showed increased biofilm formation after incubation with sub-MIC amoxicillin and penicillin. Also, the biofilm formation of A. odontolyticus was increased after incubating with sub-MIC penicillin. Coaggregation of A. naeslundii with S. gordonii and A. odontolyticus was diminished by sub-MIC amoxicillin. These observations indicated that sub-MICs of antibiotics could affect variable virulence properties such as biofilm formation and coaggregation in Gram-positive oral bacteria.

Voltammetry has shown promise as a method to estimate the concentrations of actinides in the molten LiCl-KCl used as an electrolyte in spent nuclear fuel electrorefiners. This salt typically contains several actinides in addition to many active metal fission products (rare earths, Group I & II metals). However, most of the voltammetry studies to date have focused on a single actinide or lanthanide in eutectic LiCl-KCl. This paper examines experimental and analytical techniques that can be used to estimate the concentration of a molten salt mixture containing both lanthanum (III)- and gadolinium(III)-chloride in eutectic LiCl-KCl. The aspects of the experimental procedures and setup that are unique to a multi-lanthanide mixture are briefly discussed. Experimental results from qualitative and quantitative analyses of cyclic voltammetry and open-circuit potentiometry are presented. Due to the close proximity of their standard potentials, extensive analytical work is required to estimate the concentrations. Two approaches are used in this work: peak separation and multivariate analysis. The merits of these two methods will be analyzed and discussed.

목 적: 선글라스용 렌즈의 착색농도에 따른 시력 및 망막의 대비감도 변화를 확인하여 선글라스의 생산 및 유통 관리의 선진화를 위한 기초자료를 제공하고자 하였다. 방 법: 나안 또는 교정시력이 0.7 이상이고 안질환이 없는 평균 22±3세의 대학생 30명(60안)을 대상으 로 80cd/㎡의 검사실에서 5m용 란돌트 고리 시표를 이용하여 회색 및 갈색의 선글라스용 렌즈의 착색농도 를 80%, 60%, 40%로 하여 각 단안의 시력검사를 실시하였고 F.A.C.T.(Functional Acuity Contrast Test., Stereo Optical, USA) 시표를 이용하여 대비감도 검사를 실시하였다. 결 과: 착색렌즈를 착용하지 않았을 경우의 시력이 착색렌즈를 착용하였을 때 보다 더 좋았으며 착색농 도가 진해짐에 따라 시력의 감소가 나타났다(P=0.000). 80% 착색농도의 회색렌즈에서는 착색렌즈를 착용하 지 않은 경우에 대하여 0.28±0.03, 갈색렌즈에서는 0.28±0.04의 시력감소가 나타났다. F.A.C.T. (Functional Acuity Contrast Test., Stereo Optical, USA)를 사용한 대비감도 검사에서도 회색 및 갈색렌 즈 모두에서 80% 착색농도의 렌즈에서는 전 공간주파수에서 정상범위에 미치지 못하였으며 60% 착색농도에서는 1.5 cpd를 제외한 나머지 공간주파수에서 정상범위에 미치지 못하였고 40% 착색농도에서도 6 cpd 이상의 공간주파수에서 정상범위에 미치지 못하였다. 회색 및 갈색렌즈 모두에서 1.5 cpd를 제외한 공간주 파수에서 대비감도가 유의하게 감소하였다. 결 론: 선글라스의 착색렌즈의 농도는 미용적인 요소에 의하여 선택되어지고 있으므로 안경사의 처방 시 착색농도에 의한 시력 및 대비감도의 감소를 고려하여 선글라스의 용도에 따른 착색농도가 선택되어져야 할 것이다.

This study was conducted to determine the impact of smoke-free regulations on the environment in personal computer(PC) rooms by measuring indoor levels of particulate matter smaller than 2.5 μm(PM2.5) before and after the implementation of the regulations. PM2.5 concentrations of 34 PC rooms in Seoul were measured before and after the regulations took effect. A real-time monitor was used to measure PM2.5 concentrations. A field technician recorded the characteristics of PC rooms including indoor volume, number of floors, and the presence of a smoking room and counted the number of burning cigarettes, cigarette butts, vents, and patrons. While outdoor PM2.5 concentrations and the number of patrons were not changed, indoor PM2.5 concentrations, the number of burning cigarettes and cigarette butts in PC rooms were significantly decreased after the regulations were implemented (p < 0.001). Geometric mean(GM) of indoor PM2.5 concentrations in the PC rooms was 139.6 μg/m3 before the regulations took effect and 55.7 μg/m3 after the regulations implemented. After the regulations, smokers were observed in 11 of the 34 PC rooms in which PM2.5 concentrations were not significantly decreased(p = 0.18). When smokers were not observed after the regulations, the GM of indoor PM2.5 concentrations was 37.2 μg/m3. Although PM2.5 concentrations in some PC rooms were decreased after the regulation, higher PM2.5 concentrations were observed in PC rooms with smokers. As such, compliance with the smoke-free regulations should be strictly ensured to achieve a better indoor air quality.

pH의 변화는 10%, 15%, 20% 염도 고추장에서는 숙성기간이 지나면서 약간의 pH의 감소 현상이 일어나기는 했지만, 수치에 큰 변화는 없었다. 그러나 염도가 낮은 3%와6% 고추장은 급격한 pH의 감소를 보여주었다. 호기성 세균수는 숙성기간 동안 큰 변화가 없었지만, pH의 감소 경향과 비슷하게 3%와 6% 염도 고추장에서 생균수가 더 많이 감소했다. 모든 염도에서 B. licheniformis와 B. subtilis가 큰 비중으로 차지하였다. 그러나 염도가 낮은 3%와 6% 염도 고추장에서는 이외에도 다양한 균주가 확인되었다. 호염성 세균수의 변화 추이는 호기성 세균의 생균수 변화 추이와 비슷했다. 호염성 세균도 B. subtilis가 모든 염도에서 전 숙성기간 동안 가장 큰 비중으로 확인되었다. 그러나 호염성 세균에서는 B. licheniformis 대신 Peanibacillus 속이 많은 부분에서 지배균주였다. 이외에도 3% 염도 고추장에서는 숙성 기간 동안 다양한 균주가 확인되었다. 효모는분리 유무가 숙성기간에 따라 다르게 나타났는데, 이는 pH의 급격한 저하에 의해 낮은 pH에도 생육이 가능한 균주만 숙성후기에 분리되는 것으로 판단된다. 20% 이상의 염도에서는 pH보다 고염에 의한 영향으로 효모의 증식이 어려운 것으로 보인다. 모든 염도에서 Candida 속과 S.cerevisiae가 가장 많이 분리되었으며, 이외에도 다양한 균종이 확인되었다. 검출된 휘발성 향기성분은 ester류가 26종으로 가장 많고, 그 다음 alcohol류가 12종, ketone류가 6종등 총 70종이 검출되었다. 이 중 alcohol류의 ethanol, ester류의 ethyl acetate와 3-methyl-1-butyl acetate, ketone류의 3-hydroxy-2-butanone, acid류의 acetic acid 등이 10-40% 정도의 면적비율로 검출되면서 주요한 성분으로 나타났다. 효모의 대사산물이면서 고추장의 고소한 향미를 내는ethanol은 10%와 15%에서 상대적으로 높은 비율로 검출되었고, 과실향에 기여하는 ethyl acetate는 3%, 6%, 10% 염도 고추장에서 상대적으로 높게 나타났으며, 반대로 발효유의 중요한 향기성분인 3-hydroxy-2-butanone은 염도가높아질수록 높은 비율로 검출되었다. 바나나의 향기에 중요한 3-methyl-1-butyl acetate와 초산발효에 중요한 기여를하는 acetic acid는 3%와 6% 염도 고추장에서 매우 높은수치로 검출되면서 고추장의 이취를 내는 것으로 보인다.결론적으로, 일반적인 고추장의 미생물 균총과 휘발성 향미가 달라지지 않게 제조하기 위한 고추장의 최저 염도는10%가 가장 적절할 것으로 사료된다.

This study was carried out to estimate odors emitted from toilets in Mugunghwa trains. Two parameters, odor intensity and odor concentration, were used for odor estimation. A direct olfactory method to observe odor intensity for 67 toilets and an air dilution olfactory method to estimate odor concentration for 6 samples were performed. Results showed that odor concentrations in toilets in trains ranged from 6 OU/m3 to 30 OU/m3, and odor intensity in 67 toilets varied from 0 degree to 3.3 degree. The results suggest that odors emitted from existing toilets should be controlled because the odor intensity in 16 toilets reached a level that resulted in complaints about the odor.