• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.25-39
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• 2003

Risk and exposure assessment for subsurface environment is very important for both aspects of health and environmental protection as well as making decision of remedial goal for engineering activities. Exposure due to hazardous chemicals in the subsurface environment is essential to assess risk lev121 to individual person, especially from soil and groundwater environmental media. In this paper, the status of soil and groundwater contamination is presented to discuss on the problem for environmental risk assessment. The methodologies of fate and exposure models are also discussed by conducting the case studies of exposure assessment for heavy metals, organic compounds, and dioxin compounds. In addition, the structure of exposure models and available data for model calculation are examined to make clear more realistic exposure scenarios and the application to the practical environmental issues. Three kinds of advanced remediation techniques for soil and groundwater contamination are described in this paper, The most practical method for VOCs is the bio-remediation technique in which biological process due to consortium of microorganisms can be applied. For more effective remediation of soil contaminated by heavy metals we have adopted the soil flushing technique and clean-up system using electro-kinetic method. We have also developed the advanced techniques of geo-melting method for soil contaminated by DXNs and PCB compounds. These techniques are planed to introduce and to apply for a lot of contaminated sites in Japan.

• Journal of Preventive Medicine and Public Health
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• v.47 no.1
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• pp.1-6
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• 2014

A set of exposure factors that reflects the characteristics of individual behavior capable of influencing exposure is essential for risk and exposure assessment. In 2007, the Korean Exposure Factors Handbook was, therefore, issued, driven by the need to develop reliable exposure factors representing the Korean population. The purpose of this study was to overview the development process of the Korean Exposure Factors Handbook and major recommended exposure values for the Korean population to allow information exchanges and comparison of recommended values among nations. The researchers reviewed the domestic data that could be used in the development of exposure factors, confirmed a knowledge gap, and set a priority of development by phases. A methodology to measure exposure factors was established to develop measuring techniques and test their validity. Data were processed or a survey was conducted according to the availability of data. The study thus produced recommended values for 24 exposure factors grouped by general exposure factors, food ingestion factors, and activity factors by setting up a database of exposure factors and carrying out statistical analysis. The study has significantly contributed to reducing the potential uncertainty of the risk and exposure assessment derived by the application of foreign data or research findings lacking representativeness or grounds by developing a set of exposure factors reflecting the characteristics of the Korean people. It will be necessary to conduct revisions in light of the changing statistical values of national data and the exposure factors based on Korean characteristics.

• Toxicological Research
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• v.27 no.3
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• pp.137-141
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• 2011

This study was conducted to assess the exposure risk through inhalation to baby powder for babies and adults under simulated conditions. Baby powder was applied to a baby doll and the amount of baby powder consumed per application was estimated. The airborne exposure to baby powder during application was then evaluated by sampling the airborne baby powder near the breathing zones of both the baby doll and the person applying the powder (the applicator). The average amount of baby powder consumed was 100 mg/application, and the average exposure concentration of airborne baby powder for the applicator and baby doll was 0.00527 mg/$m^3$ (range 0.00157~0.01579 mg/$m^3$) and 0.02207 mg/$m^3$ (range 0.00780~0.04173 mg/$m^3$), respectively. When compared with the Occupational Exposure Limit of 2 mg/$m^3$ set by the Korean Ministry of Labor and the Threshold Limit Value (TLV) of 2 mg/$m^3$ set by the ACGIH (American Conference of Governmental Industrial Hygienists), the exposure concentrations were much lower. Next, the exposure to asbestos-containing baby powder was estimated and the exposure risk was assessed based on the lung asbestos contents in normal humans. As a result, the estimated lung asbestos content resulting from exposure to asbestos-containing baby powder was found to be much lower than that of a normal Korean with no asbestos-related occupational history.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.239-245
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• 2013

Occupational exposure and risk assessment were conducted to evaluate the safety of operators when insecticide acetamiprid was applied to apple orchard using a speed sprayer. Dermal patches, cotton gloves, socks, and masks were used to monitor the dermal exposure, and personal air pump with solid sorbent was used to measure the potential inhalation exposure. In validation to analytical methods, the limit of detection and limit of quantitation were 0.25 ng and 1 ng, respectively. Good reproducibility (coefficient variation < 4%), linearity (coefficient determination > 0.999), and recovery (85.3-118.2%) were obtained. Trapping efficiency of solid sorbent was 96.4% while breakthrough did not occur. Only hand exposure was measured on the gloves during mixing/loading to give $33-1,132{\mu}g$. Exposure amount of operator 3 among 4 workers was noticeably high. The total volumes of spray liquid for operators were $535-1,235mL{\cdot}h^{-1}$, corresponding to 0.03-0.08% of the applied spray solution. Highest contaminated parts of body were thighs, chest, and lower legs. The inhalation exposure ratio to the total application amount was significantly low. However, wind seemed to affect the inhalation exposure of operator. For risk assessment, margin of safety was calculated by the application of cloth and dermal penetration rate to obtain values of much larger than 1 in all cases. Therefore, health risk of operators during treatment of acetamiprid in apple orchard could be of least possibility.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.28 no.1
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• pp.1-17
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• 2018

Objectives: This research is part of a study to be conducted over five years starting from 2017 by the Ministry of Environment on the development of technologies to evaluate the impact of chemical accidents on the human body. Methods: For this research, a five-stage specific study method was developed. Results: In brief, the developed health risk assessment method can be summarized as follows. First, a health risk assessment system was built based on the guidelines set forth by the USA NRC/NAS. Second, based on the disease manifestation theory, the health risk assessment method was divided into 1) a carcinogenic health risk assessment method focused on all carcinogens except non-genotoxic carcinogens and 2) a non-carcinogenic health risk assessment method focused on noncarcinogens including non-genotoxic carcinogens. Third, the detailed contents of the health risk assessment method were developed in four stages(hazard identification, dose-response assessment, exposure assessment, and risk determination) through theoretical consideration of the assessment of the level of health risk related to chemical exposure. Finally, a health risk assessment methodology, classified into stages to address acute, subacute/subchronic, and chronic conditions was developed after considering the physicochemical behavior of hazardous chemicals upon implementation of countermeasures after a chemical accident. Conclusions: A method to evaluate the health risks related to toxic chemicals generated by chemical accidents was developed. This study was performed with the purpose of developing a mathematical health risk assessment method to evaluate the health effects of exposure to hazardous chemicals upon implementation of emergency countermeasures after chemical accidents.

• Journal of Environmental Health Sciences
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• v.49 no.4
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• pp.210-217
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• 2023

Background: N-nitrosamines are carcinogenic substances often found in rubber products. They are produced when certain additives of rubber products react with nitrite in saliva or air. Exposure assessment for the proper management and communication of N-nitrosamines in rubber balloons should be carried out. Objectives: This study was conducted to determine the concentrations of N-nitrosamines in rubber balloons in the South Korean market and assess exposure among Korean children. Methods: Forty eight rubber balloon products in the domestic market were purchased and a total of 68 balloons were analyzed for N-nitrosamines and N-nitrosatable substances. Chemical analysis was conducted by HPLC-MS/MS according to the method EN 71-12. For exposure assessment, an exposure algorithm and coefficients were obtained from previous studies. Results: Among the 68 rubber balloons, N-nitrosamines were detected in 18 (26.5%) with an average level of 60.77 ㎍/kg. N-Nitrosatable substances were detected in 44 products (64.7%) with an average level of 1353.33 ㎍/kg. As a result of the exposure evaluation, the exposure dose differed according to how exposure coefficients were applied. The median exposure (50th percentile) was higher in the age group of 6~12 years, and high exposure (95th percentile) was higher in the age group of 13~18. Conclusions: We evaluated the N-nitrosamines contained in rubber balloons purchased in the domestic market and assessed oral exposure among South Korean children. For integrated risk management of N-nitrosamines, further studies and discussion regarding exposure and risk assessment are required.

• Journal of Soil and Groundwater Environment
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• v.16 no.1
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• pp.32-41
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• 2011

By using a newly developed Korean risk-based corrective action (K-RBCA) software (K-RBCA) and the RBCA Tool Kit, risk assessment was performed on a site that was contaminated with aromatic hydrocarbons and heavy metals. Eight chemicals including benzene, ethylbenzene, xylenes, naphthalene, benz(a) anthracene, benzo(b) fluoranthene, benzo(a) pyrene, and arsenic that exceeded the US EPA Soil Screening Level were chosen as the target pollutants. A conceptual site model was constructed based on the site-specific effective exposure pathways. According to the RBCA Tool Kit the carcinogenic risk of arsenic was larger than $10^{-6}$, which is the generally acceptable carcinogenic risk level. The K-RBCA estimated the same level of carcinogenic risk for arsenic. With the RBCA Tool Kit, the carcinogenic risk of benzo(a) pyrene was estimated to be about $1.3{\times}10^{-6}$. However, with the K-RBCA benzo(a) pyrene did not exhibit any risk. The inconsistency between the softwares was attributed to the different fundamental settings (i.e., medium division) between the two softwares. While the K-RBCA divides medium into surface soil, subsurface soil, and groundwater, the RBCA Tool Kit divides medium into only soil and groundwater. These differences lead to the different exposure pathways used by the two softwares. The K-RBCA considers the exposure pathways in surface soil and subsurface soil separately to estimate risk, however, the RBCA Tool Kit considers the surface soil and subsurface soil as one and uses the integrated exposure pathways to estimate risk. Thus the resulting risk is higher when the RBCA Tool Kit is used than when the K-RBCA is used. The results from this study show that there is no significant difference in the risks estimated by the two softwares, thus, it is reasonable to use the K-RBCA we developed in risk assessment of soil and groundwater. In addition, the present study demonstrates that the assessor should be familiar with the characteristics of a contaminated site and the assumptions used by a risk assessment software when carrying out risk assessment.

• Journal of Environmental Policy
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• v.7 no.1
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• pp.1-29
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• 2008

The Ministry of Environment(MoE) of Korea has recently established the Environmental Health Act. This Act contains a clause related to implementation of Health Impact Assessment(HIA). So, selecting a landfill which was expected to have an influence on human health among major development projects, this study carried out the human risk assessment due to inhalation exposure to landfill gas emission and attempted to measure the possibility of domestic application of HIA in the future. The process for HIA on landfill site extension focusing on human risk assessment is as follows: The first step is to presume and calculate the amount of landfill gas emissions using LandGEM, The second step is to carry out exposure assessment using K-SCREEN Model which is used for predicting the concentration in a conservative method. The last step is to carry out human risk assessment of carcinogenic and non-carcinogenic substances. It is considered that it is likely to apply a technique for human risk assessment due to inhalation exposure to landfill gas emission performed here more specifically in the case of implementing HIA. In addition, it is also believed that more systematic studies are needed to overcome some weak points and limits found in this study and if these weak points and limits are improved more reliable outcomes will be produced.

• Environmental Analysis Health and Toxicology
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• v.4 no.1_2
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• pp.55-65
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• 1989

Nevertheless the serious environmental pollution in Korea has been discussed in concern with health effect, the significant effect are not determined easily. Toxicological method has been used to establish safe levels of exposure for environmental pollutants to have threshold health effect below which significant effects are unlikely to occur. However the conventional method cannot to establish safe levels of exposure for non-threshold pollutants have been used to express comprehensive pollution degree, not in detailed toxic effects. Acceptable exposure or risk levels are decides by policymakers who consider descriptions and estimates of risks together with social and economic benefits. This paper focuses on the concept development of risk assessment and describes some risks of environmental pollution based on the surveyed date in Korea. The current concepts of risk assessment in policy descisions can be explored and areas for possible improvement, given current scientific knowledge are identified. The experience of foreign countries can provide a realistic basis for evaluating the existing data of environmental pollutants. To improve the environmental quality, risk regulation should be managed as soon as possible in Korea.

• Environmental Analysis Health and Toxicology
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• v.19 no.1
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• pp.65-72
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• 2004

Environmental risk assessment of cadmium compounds was conducted using national monitoring data of aquatic and terrestrial compartments of local area. Aquatic and terrestrial toxicities of cadmium compounds on algae, daphnid, fish, earthworm, springtails and other species were evaluated. The toxicity data evaluated in this study were mainly from ECOTOX database provided by US EPA. Assessment factors were determined according to the EU technical guidance document and/or OECD proposal. Predicted no effect concentration (PNEC) values of aquatic and terrestrial toxicity were 25$\mu\textrm{g}$/L and 0.2 mg/kg, respectively and they were compared with cadmium exposure data of several local areas, which were used as Predicted exposure concentration(PEC) values. Most of the local area were found to be not risky. However, the risk values (PEC/NEC) of some metropolitan areas were greater than 1 when the most conservative PNEC value was applied.