Lilium longiflorum의 花器組織培養

鄭載東(Chung Jae Dong),全在琪(Chun Jae Ki),申芝愛(Shin Ji Ae) 한국원예학회 1984 Horticulture, Environment, and Biotechnology Vol.25 No.2

Health and Social Problems of Carbon Monoxide Poisoning from the Usage of Anthracite Coal in Korea

정용,신동천,임영욱,Chung, Yong,Shin, Dong-Chun,Lim, Young-Wook The Korean Society of Environmental Toxicology 1990 환경독성보건학회지 Vol.5 No.3

음용수중 Trihalomethane의 오염과 그 위해성에 관한 조사연구 - 주요 14개도시를 대상으로 (1988. 9-1989. 2) -

정용,신동천,이보영,유승한,정상혁,Chung, Yong,Shin, Dong-Chun,Lee, Bo-Young,Yu, Sung-Han,Chung, Sang-Hyuk 대한예방의학회 1989 Journal of Preventive Medicine and Public Health Vol.22 No.4

This study was conducted as a nationwide survey In Korea to determine the THM (trihalomethane) concentration levels in the drinking water of 14 selected cities. The survey was underdtaken in one city (Kwangju) during September and October of 1988 and 14 cities in January through February of 1989. The results were as follows : 1. The $KMnO_4$ consumption was 10.6mg/l-11.6mg/l in Pusan and Ulsan, exceeding the drinking water standard of 10mg/l. Pusan, Inchon, Kwangju, Ulsan, Mokpo and Junju areas also exceeded the ammonia nitrate standard of 0.5mg/l. Other tap waters surveyed were detected below the drinking water standards. 2. The THM concentrations of tap water measured in January and February of 1989 were detected in the range $1.20{\mu}g/l-150.8{\mu}g/l$. 3. In the comparative study of the THM concentration of tap water measured in the Kwangju area during September and October of 1998, the average THM concentation of $145.63{\pm}70.72{\mu}g/l$ showed a sixfold increase compared to that of $23.8{\pm}8.31{\mu}g/l$ surveyed in January and February 1989. 4. The proportion of the four THM compounds found in tap water was bromoform, 47% ; chloroform, 30% ; chlorodibromomethane, 13% ; and dichlorobromomethane, 10%. 5. Since the results indicate that the concentration of bromoform was 2-10 times higher than that of chloroform measured in the seaside district of Pusan, Ulsan and Cheju Island, it is reasonable to assume that the raw water was somehow Influenced by seawater. 6. The average lifetime cancer rate of the population exposed to chloroform measured in the surveyed areas was 17 cancer incidences per 1 million population. From the above results, the existence of THM in the distribution systems seems to be inevitable, since chlorine disinfection is performed in water treatment plants In our country. There seems to be a trend of increasing. THM cncentrations due to the contamination of raw water. In order to establish my form of regulations, health risk assessment is an imminent subject.

상수의 염소처리시 생성되는 소독부산물 중 Haloacetic acid류의 생성능에 관한 연구 - 일부 상수원수를 대상으로 -

정용,신동천,임영욱,김준성,박연신,Chung, Yong,Shin, Dong-Chun,Lim, Young-Wook,Kim, Jun-Sung,Park, Yeon-Shin 환경독성보건학회 1997 환경독성보건학회지 Vol.12 No.3

The main reason of applying chlorination is to sterilize microbes existing in the drinking water treatment. But chlorination could lead to the formation of disinfection by-products (DBPs) by the reaction of free chlorine with humic substance in the water. Especially the DBPs including trihalomethanes (THMs), haloacetic acids (HAAs), haloacetonitriles (HANs), and haloketones (HKs) exist in the tap water. The US environmental protection agency (US EPA) defines that trihalomethanes, dichloroacetic acid, trichloroacetic acid, and dichloroacetonitrile among DBPs are probable/possible human carcinogens. US EPA suggests maximum contaminant levels (MCLs) for THMs (80$\mu$g/L) and HAAs (60$\mu$g/L) in drinking water. In Korea, THMs in drinking water has been surveyed but DBPs in general has not been studied in drinking water practically. Therefore only THMs have been regulating as criteria compounds since 1990 but neither HAAs nor HANs. Researches on HAAs are yet to be found. HAA formation potentials(HAAFPs) have not been practiced. HAAs depends on the characteristics of water sources by chlorination. In this study, HAAFPs from three distinct sources were investigated by laboratory chlorination experiments. This study was performed to measure the level of HAAs in drinking water in Seoul area. At April 1996, after collecting the raw waters from the three sites with the different properties, the water samples were chlorinated at various conditions(pH 5.5, pH 7.0 and without pH adjustment) in the state of raw water to have 0. 5mg/L of residual chlorine concentration. And the raw water, treated water, and tap water of water treatment were collected to measure the HAAs concentration. The quantitative analysis of HAAs was conducted by US EPA methods.

수도수중 염소 소독부산물로 인한 건강위해성 평가에 관한 연구 - 서울시 수도수중 Trihalomethanes 및 Haloaceticnitriles을 중심으로 -

정용,신동천,양지연,박연신,김준성,Chung, Yong,Shin, Dong-Chun,Yang, Ji-Yeon,Park, Yeon-Shin,Kim, Jun-Sung 환경독성보건학회 1997 환경독성보건학회지 Vol.12 No.3

Public concerns about hazardous health effect from the exposure to organic by-products of the chlorination have been increased. There are numerous studies reporting that chlorination of drinking water produces numerous chlorinated organic by-products including THMs, HAAs, HANs. Some of these products are known to be animal carcinogens. The purpose of this study was to estimate health risk of DBPs by chlorinated drinking water ingestion in Seoul based on methodologies that have been developed for conducting risk assessment of complex-chemical-mixture. The drinking water sample was collected seperately at six water treatment plant in Seoul at March, April, 1996. In tap water of households in Seoul, DBPs were measured wilfh the mean value of 36.6 $\mu$g/L. Risk assessment processes,. which include processes for the estimation of human cancer potency using animal bioassay data and calculation of human exposure, entail uncertainties. In the exposure assessment process, exposure scenarios with various assumptions could affect the exposure amount and excess cancer risk. The reference dose of haloacetonitriles was estimated to be 0.0023 mg/kg/day by applying dibromoacetonitrile NOAEL and uncertainty factor to the mean concentration. In the first case, human excess cancer risk was estimated by the US EPA method used to set the MCL (maximum contaminant level). In the second and third case, the risk was estimated for multi-route exposure with and without adopting Monte-Carlo simulation, respectively. In the second case, exposure input parameters and cancer potencies used probability distributions, and in the third case, those values used point estimates (mean, and maximum or 95% upper-bound value). As a result, while the excess cancer risk estimated by US EPA method considering only direct ingestion tended to be underestimated, the risk which was estimated by considering multi-route exposure without Monte-Carlo simulation and then using the maximum or 95% upper-bound value as input parameters tended to be overestimated. In risk assessment for Trihalomethanes, considering multi-route exposure with adopting Monte-Carlo analysis seems to provide the most reasonable estimations.

채소류 중 발암성 농약의 위해성 평가

윤재홍,정용,신동천,이종태,Yoon, Jae-Hong,Chung, Yong,Shin, Dong-Chun,Lee, Jong-Tae 대한예방의학회 1999 Journal of Preventive Medicine and Public Health Vol.32 No.2

Objectio ostinato the carcinogenic risks from the ingestion of some carcinogenic pesticides (CPs) in vegetables sampled at a local agricultural product market in Seoul. Methods: After applying a hazard identification step, we selected four pesticides, such as DDT, dieldrin, folpet, and heptachlor epoxide, for this risk assessment. Concentrations of each pesticide were measured from randomly sampled vegetables. In order to estimate the human exposure levels, we combined the concentration of pesticides in the vegetables with consumption rate of those vegetables. Three scenarios were hypothesized for human exposure assessment. Scenario I was the most conservative which supposed the undetected CPs would be the detection limit values. Scenario II was assumed that the undetected CPs would be a half of the detection limit values, and finally scenario III merely considered only values greater than the detection limit values. We finally presented the estimated carcinogenic risks on the basis of the traditional risk assessment procedure suggested by U.S. EPA. Results: Pesticides including DDT, dieldrin, folpet and heptachlor epoxide were detected in 9 samples (6%) in the range of $0.0006\sim0.09ppm$. The daily intake levels of carcinogenic pesticides were estimated in the range of $0.0009\sim0.0079{\mu}g/day$. As we expected, excess cancer risks based on scenario I was also the highest $(1.1\times10^{-8}\sim5.5\times10^{-5})$. Conclusions: We found that the estimated risks from the pesticides we investigated were not serious. We, however, propose that a continuos monitoring is needed to make sure for the protection of public health.

환경성 발암물질의 용량-반응모델의 이론적 근거와 응용에 관한 연구 - 음용수 중 chloroform을 중심으로

신동천,정용,김종만,이성임,황만식,Shin, Dong-Chun,Chung, Yong,Kim, Jong-Man,Lee, Seong-Im,Hwang, Man-Sik 대한예방의학회 1996 예방의학회지 Vol.29 No.1

This study described methods to predict human health risk associated with exposure to environmental carcinogens using animal bioassay data. Also, biological assumption for various dose-response models were reviewed. To illustrate the process of risk estimate using relevant dose-response models such as Log-normal, Mantel-Bryan, Weibull and Multistage model, we used four animal carcinogenesis bioassy data of chloroform and chloroform concentrations of tap water measured in large cities of Korea from 1987 to 1995. As a result, in the case of using average concentration in exposure data and 95% upper boud unit risk of Multistge model, excess cancer risk(RISK I) was about $1.9\times10^{-6}$, in the case of using probability distribution of cumulative exposure data and unit risks, those risks(RISK II) which were simulated by Monte-Carlo analysis were about $2.4\times10^{-6}\;and\;7.9\times10^{-5}$ at 50 and 95 percentile, respectively. Therefore risk estimated by Monte-Carlo analysis using probability distribution of input variables may be more conservative.

서울시 대기중 유기오염물질의 농도와 돌연변이원성에 대한 연구

신동천,정용,문영한,노재훈,Shin, Dong-Chun,Chung, Yong,Moon, Young-Hahn,Roh, Jae-Hoon 대한예방의학회 1990 Journal of Preventive Medicine and Public Health Vol.23 No.1

To evaluate the difference of concentration and mutagenicity of organic pollutants between residential and traffic area of Seoul, air samples were collected in Bulkwang (residential) and Shinchon (traffic) area. Samples were analyzed to measure the concentration of extractable organic matters (EOM) and their subfractions and mutagenicities were tested using Salmonella typhimurium TA 98. The concentrations of polycyclic aromatic hydrocarbons (PAHs) were also measured by gas-chromatography and compared between two areas. The results were as follows ; 1. While the concentration of total suspended particulate (TSP) in residential area was below the environmental standard in annual average, the concentration in traffic area was above the standard and was up to its maximum $256{\mu}g/m^3$ in November. The difference of TSP concentrations in both areas of each month was statistically significant (P<0.05). 2. The concentration of fine particle in traffic area was significantly higher compare to that in residential area and showed statistically significant monthly difference in both areas (P<0.05). The proportion of concentration of fine particle to TSP was 55-68%. 3. Mean concentrations of EOM in residential and traffic areas were $4.3{\mu}g/m^3\;and\;5.3{\mu}g/m^3$ respectively. The proportion of amount of EOM from fine particle to EOM from TSP was 70-88%. 4. While the percentage of polar neutral organic compounds (POCN) of fine particle in Bulkwang's sample was higher compare to Shinchon's sample, the percentage of aliphatic compounds of fine particle in Shinchon's sample was higher compare to Bulkwang's sample. The percentages of PAH fraction were as low as 6-10% in both areas. 5. The mutagenic activity of nit concentration of organic matters extracted from fine particle was higher compare to that of coarse particle and was increased when metabolically activated with S9. Mutagenicities with metabolic activation calculated by unit air volume were significantly different between residential and traffic area, $17\;revertants/m^3$\;and\;22\;revertants/m^3$ respectively. 6. The concentrations of benzo(a)pyrene in fine particle of traffic and residential areas were $3.10ng/m^3\;and\;2.02ng/m^3$ respectively. Sixteen PAHs were higher in samples of traffic area compare to residential area and also concentrations of PAHs in fine particle were higher compare to coarse particle.

서울시 일부 교통지역의 대기 부유분진 중 유기오염물질에 대한 발암 위해성 평가

신동천,정용,김종만,박성은,임영욱,Shin, Dong-Chun,Chung, Yong,Kim, Jong-Man,Park, Seong-Eun,Lim, Yong-Wook 대한예방의학회 1994 Journal of Preventive Medicine and Public Health Vol.27 No.2

Due to rapid industrialization and economic development since 1970's, Seoul has become known as one of the most heavily polluted cities in the world. This is especially because of its air pollution. This study was conducted to characterize the cancer risk from organic pollutants in the suspended particulates of Seoul. Extractable organic matter (EOM) and PAHs in Shinchon, a major traffic area, were measured monthly in two periods of Aug. $1987{\sim}sep.$ 1988, and Sep. $1990{\sim}Aug.$ 1991. While the differences both of EOM and benzo(a)pyrene concentrations between these two periods were not significant (P>0.05), the differences between heating and non-heating seasons were significant (p<0.01). The estimated mean concentrations of EOM and benzo(a)pyrene in fine particles in non-heating season were $3.98{\mu}g/m^3\;and\;0.51ng/m^3$ respectively, and in heating season were $6.75{\mu}g/m^3\;and\;2.96ng/m^3$ respectively, in these two periods combined. The calculated risk from EOM was compared with that from benzo(a)pyrene and also these values were compared with the level of acceptable risk.

환경정보 검색 시스템의 활용에 관한 연구 대기오염 물질의 위험성 확인을 중심으로

김선정,신동천,정용,구자건 ( Sun Jeong Kim,Dong Chun Shin,Yong Chung,Ja Kon Koo ) 한국환경영향평가학회 1996 환경영향평가 Vol.5 No.1

The objective of this study is to establish the application method of environmental information system which is related to hazard identification for Health Risk Assessment. For establishing the environmental information system, fourteen hazardous chemicals were chosen and applicated to the database network such as RTKNET(Right Know Net), MSDS(Material Safety Data Sheets), TRI(Toxic Release Inventory), IRIS, AIRS, etc. The searching method of environmental information is classified to three sections such as the domestic commercial information company, international database agencies, and internet. Recently the importance of environmental information is being emphasized because it is essential to use database system in the field of environmental studies. Most of the foreign research organizations are communicating actively for information exchange, and the improvement of the quality of research. It is required to accumulate the data and develop them to database for future research.