• 한국환경보건학회지
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• 제33권5호
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• pp.365-371
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• 2007

To evaluate the effect of air pollution on respiratory health in children, We conducted a longitudinal study in which children were asked to record their daily levels of Peak Expiratory Flow Rate(PEFR) using potable peak flow meter(mini-Wright) for 4 weeks. The relationship between daily PEFR and ambient air particle levels was analyzed using a mixed linear regression models including gender, age in year, weight, the presence of respiratory symptoms, and relative humidity as an extraneous variable. The daily mean concentrations of $PM_{10}$ and $PM_{2.5}$ over the study period were $64.9{\mu}g/m^3$ and $46.1{\mu}g/m^3$, respectively. The range of daily measured PEFR in this study was $182{\sim}481\;l/min$. Daily mean PEFR was regressed with the 24-hour average $PM_{10}(or\;PM_{2.5})$ levels, weather information such as air temperature and relative humidity, and individual characteristics including sex, weight, and respiratory symptoms. The analysis showed that the increase of air particle concentrations was negatively associated with the variability in PEFR. We estimated that the IQR increment of $PM_{10}$ or $PM_{2.5}$ were associated with 1.5 l/min (95% Confidence intervals -3.1, 0.1) and 0.8 l/min(95% CI -1.8, 0.1) decline in PEFR. Even though this study showed negative findings on the relationship between respiratory function and air particles, it was worth noting that the findings must be interpreted cautiously because exposure measurement based on monitoring of ambient air likely resulted in misclassification of true exposure levels and this was the first Korean study that $PM_{2.5}$ measurement was applied as an index of air quality.

• 농약과학회지
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• 제9권4호
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• pp.347-353
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• 2005

한국 농업환경에서 benzimidazole계 살균제의 안전사용 및 농약살포자를 보호하기 위하여 단기(30일 이내) 및 장기(6개월 이상) 노출에 대한 농작업자 위해성평가를 수행하였다. 농작업자의 노출량 산출은 일본의 EPN 45% 유제 노출시나리오를 이용하였으며, 일일 작업시간은 4시간으로 가정하였고, 작업자에 대한 급성 및 만성 허용노출량(AOEL)은 단기노출은 기형독성, 만성노출은 만성독성 NOAEL로부터 산출하였다. Benzimidazole계 농약들은 US/EPA가 $Q_1^*$를 설정하여 발암성평가를 하고 있는 농약들로서 본 연구에서도 작업자의 만성 노출에 대한 발암성평가를 평균일일노출량(LADD)를 일생 동안 농업에 종사하는 연수, 농약살포 횟수, 농업형태 등을 고려하여 평가하였다. 농작업자에 대한 농약 노출량은 benomyl, carbendazim 및 thiophanate-methyl에 대하여 각각 0.2, 0.36 및 0.42 mg/kg/day 이었고, sAOEL은 0.3, 0.1 및 0.2 mg/kg/day 이었으며, cAOEL의 경우 benomyl과 carbendazim은 0.025, thiophanate-methyl은 0.08 mg/kg/day이었다. 만성 및 발암위해성평가를 위한 LADD는 benomyl 0.0038, carbendazim 0.0067 및 thiophanate-methyl 0.0081mg/kg/day로 산출되었다. 위의 수치를 이용하여 AOEL/exposure를 산출한 결과 급성위해성은 $0.28{\sim}1.5$, 만성 위해성은 $3.73{\sim}9.88$로서 작업자에 대한 급성 위해성은 보호장비를 착용할 경우 최대 90%까지 노출량이 감소하므로 보호장비 착용시 안전할 것으로 생각되었으며, 만성 위해성은 AOEL/exposure가 1 이상으로서 안전한 것으로 판단되었다. 발암위해성평가 결과는 보호장비를 착용할 경우 $9.12{\times}10^{-7}{\sim}1.13{\times}10^{-5}$으로 실제적인 농약살포 인자를 고려하여 평가하면 농약살포자에 대한 위해성은 없을 것으로 추정되나 보다 실제적인 노출성적을 이용한 농약살포 작업자 위해성평가가 필요하리라 판단된다.

• 한국대기환경학회지
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• 제18권4호
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• pp.327-334
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• 2002

The work presents sensitivity and uncertainty analysis of 2-compartment model for the evaluation of indoor radon pollution in a house. Effort on the development of such model is directed towards the prediction of the generation and transfer of radon in indoor air released from groundwater. The model is used to estimate a quantitative daily human exposure through inhalation of such radon based on exposure scenarios. However, prediction from the model has uncertainty propagated from uncertainties in model parameters. In order to assess how model predictions are affected by the uncertainties of model inputs, the study performs a quantitative uncertainty analysis in conjunction with the developed model. An importance analysis is performed to rank input parameters with respect to their contribution to model prediction based on the uncertainty analysis. The results obtained from this study would be used to the evaluation of human risk by inhalation associated with the indoor pollution by radon released from groundwater.

• Toxicological Research
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• 제6권2호
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• pp.121-130
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• 1990

Pregnant Wister rats were given daily subcutaneous administrations of methamphetamine (MAPT; varying doses ranging from 1.0 to 4.5mg/kg) from days 7 to20 of gestation and teratogenic effects have been determined. The teratogenic effects inducible with orally administered caffeine (90mg/kg/day)for the same durations were used as the positive controls. MAPT doses greater than 2.0 mg/kg have suppressed the rate of maternal weight gain. Some of the offsprings (F1) of the prenatal MAPT treated groups had decreased growth rate and delayed development of physical characters and functional reflexes. The male offsprings of the MAPT treated groups had significant decreases in their spontaneous motor activity but had enhanced conditioned avoidance responses. However, the mating performances of these offsprings were not affected. These results indicated that prenatal exposure of MAPT may induce some behavioral teratogenicity in rats.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.230-231
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• 2018

Recently, the danger for radioactive materials has become a hot topic. Beginning with the Chernobyl nuclear accident in 1996, in 2011, the Fukushima nuclear power plant in Japan suffered major damage such as large-scale casualties and radioactive dangerous area selection. Concerns about leakage of radioactive materials due to recent earthquakes have been deepening in Korea, such as Wolsong Nuclear Power Plant in Gyeongju, and there is a growing interest in the safety of radioactive materials through the media and the media. However, the route to exposure to radioactive materials is not limited to these large-scale nuclear accidents. Typical examples of this are radioactive substances exposed in daily life. In the case of radon gas, the danger is being revealed through current events programs and news, and natural radiation exposure is attracting attention.

• 대한전기학회논문지:전력기술부문A
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• 제48권7호
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• pp.832-838
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• 1999

Recently, there are growing concerns about power frequency electric and magnetic fields coming out from the high voltage transmission lines, because of the wide spread perception of their probable harmful effect on human body. In connection with this trend, this paper describes the electric and magnetic fields measurement result around 154 kV and 345 kV transmission lines, a comparison of measured EMF to calculated one and the correlations between transmission lines currents and measured magnetic fields. Daily maximum and minimum magnetic field quantities under the selected 154 kV and 345 kV transmission lines had been measured for 1 year of 1997 and the average value of magnetic field exposure under the lines were calculated and presented based on the measured data.

• 한국환경성돌연변이발암원학회지
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• 제19권1호
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• pp.39-45
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• 1999

Human Carcinogenic Potency (HCP) can be estimated based on human daily exposure dose to carcinogen (Dh), body weight (Wh), 10% tumorigenic dose (TD10), and slope factor at TD10 (Q10) from 2-yr bioassay data. This approach is more relevant to humans generally exposed to low doses of carcinogens and can reduce more of extrapolation errors from high dose in animal experiments to low dose in humans than HERP (human exposure dose/rodent potency dose) proposed by Ames et al. (Science, 236, 271-280, 1987). TD50 and HERP have been routinely used to compare rodent carcinogenic potency and human carcinogenic potency, but those approaches have had limitations in extrapolation of high dose to low dose in humans. The advantages of HCP are to estimate human exposure dose (Dh) by human monitoring instead of environmental monitoring, to consider slope factor (Q10) which reflects the tendency of curve at low dose, and to use TD10 which represents much lower dose thant TD50 or HERP. HCP will be a useful parameter for the estimation of human carcinogenic potency in risk assessment and management of carcinogens.

• 한국환경농학회지
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• 제12권3호
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• pp.255-263
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• 1993

The demand of safety assessment for pesticide residues in foods is growing in Korea. In order to assess the actual dietary exposure toward pesticide residues, the problems in utilization of pesticide residue data were reviewed and optimization of food factors applicable to Korean population was conducted. The problems and current status in setting pesticide residue tolerance-domestic and foreign-in foods were also argued. The conclusion is summarized as follows: (1) Anticipated residue estimates(ARE) calculated from field trial residue data, the percentage of crop treated, and the effects of cooking or processing should be utilized for dietary exposure assessment in a real sense. (2) Average daily intake of total foods per person in Korea was 1,104g in 1970's and 1,240g in 1980's. Much variation was observed between the two decades by food commodities. (3) Pesticide residue tolerances in Korea have been established at relatively lower levels in comparison with FAO/WHO or western countries. More extensive studies and data accumulation as related to tolerance setting are called for in future for the sake of health protection and smooth interstate trade.

• Journal of Preventive Medicine and Public Health
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• 제36권4호
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• pp.314-322
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• 2003

Objectives : In this study, the exposure status of the hazardous substances from incinerators, such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), were studied , and the relationship between the exposure of these hazardous substances and their heath effects on the workers and residents near municipal solid waste (MSW) incinerators and an industrial incinerator investigated. Methods : Between July 2001 and Jure 2002, 13 workers at two MSW incinerators, 16 residents from the area around the two MSW incinerators, 6 residents from the control area, and further 10 residents near an industrial incinerator, estimated to emit higher levels of hazardous substances, were interviewed. Information, including sociodemographic information, personal habits, and work history, detailed gynecologic and other medical history were collected through interviews. Blood samples were also collected from 45 subjects, and analyzed for PCDD/DFs, by high resolution gas chromatography -high resolution mass spectrometry, using the US EPA 1613 method. In addition to the questionnaire survey, urinary concentrations of 8-hydroxydeoxyguanosine (8-OH-dG) and malondialdehyde (MDA) were measured as oxidative injury biomarkers. The urinary concentrations of 8-OH-dG were determined by in vitro ELISA, and the MDA by HPLC, using u adduct with thiobarbituric acid. Results : The PCDD/DFs concentrations in the residents near the industrial incinerator were higher than those in the controls, workers and residents near the MSW incinerators. The average TEQ (Toxic Equivalencies) concentrations of the PCDD/DFs in residents near the industrial incinerator were 53.4pg I-TEQs/g lipid. The estimated daily intakes were within the tolerable daily intake range (1-4 pg I-TEQ/Kg bw/day) suggested by WHO (1997) in only 30% to the people near the industrial incinerator. Animal studies have already shown that even a low body border of PCDD/DFs, such as 10 ng TEQ/kg bw, can cause oxidative damage in laboratory animals. Our study also showed that the same body burden of PCDD/DFs can cause oxidative damage to humans. Conclusions : The exposures to PCDD/DFs and the oxidative stress of residents near the industrial incinerator, were higher than those in the controls, workers and residents near the MSW incinerators. Proper protection strategies against these hazardous chemicals are needed. Because a lower body burden of PCDD/Fs, such as 10ng TEQ/kg bw, can cause oxidative damage, the tolerable daily intake range should be restrictedly limited to 1pg I-TEQ/kg bw/day.

• 한국동물학회지
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• 제9권1호
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• pp.7-15
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• 1966

In a previous paper, the dirunal and monthly changes of the tidal flat temperature and chlorinity were observed. In this paper the resistance of the young short necked clam in various growth stages to the temperature, to the chlorinity and to the exposure were studies. The young clam used were in early (E), medium (M) and late (L) young stages whose shell lengths were 2.0-3.5mm, 9.0-11.0mm. and 14.0-16.0mm., respectively. The results were : 1. At various sea water temperatures , the chlorinity resistance of the young clam was directly proportional to the shell length. 2. When both inadequate sea water temperature and abnormal chlorinity are simultaneously applied, the resistance of these young clams was more markedly reduced than the case of applying either one of these conditions. 3. In clams of M and L, no lethal effect were observed when daily immersion of four to eight hours for a week into the sea water of any concentration of chloriity at 26-34$^{\circ}C$, whereas in E, 37-90% of mortalities were obtained by immersion of eight hours daily into both the fresh water and the sea water of higher chloriniites (more than 23.5$\textperthousand$ Cl) at the same temperature above. 4. The lower critical thermal maximum for lethal to the young clam was 38$^{\circ}C$. With four hours immersion daily at the water temperature of 38$^{\circ}C$, the mortalities of E, M and L to the lower chlorinities (less than 6.7$\textperthousand$Cl) were 100, 70-100 and 27-37% respectively ; to the higher chlorinities (more than 23.5$\textperthousand$Cl) 10-70, 10-37 and 3 % respectively ; to the normal range of chlorinities (13.4-16.8$\textperthousand$Cl) 0-13, 3 and 0 % respectively. 5. No lethal effects were observed in E and M clams immersed continuously for seven days in sea water with chlornities of 7.2 -21.7$\textperthousand$Cl at 18-24$^{\circ}C$, while notable mortalities were observed in E which had been kept at lower (less than 4.8$\textperthousand$ Cl) and higher (more than 24.1$\textperthousand$ Cl) chlorinites. 6. Although the resistance of the young clam to the chlorinity may have to be related closely to the life history of the clam prior subject to the experiment, the adapted chlorinity range was 7.2-19.3$\textperthousand$ Cl and the optimum range was 13.4-16.8$\textperthousand$Cl. 7. Remarkable lethal effects were observed for the E and M clams to the exposure temperature of 38$^{\circ}C$ whereas the L and had no such fatal results.