This research, sponsored by the Korean Ministry of Environment in 2014, was the first epidemiological study in Korea that investigated the health impact assessment of radon exposure. Its purpose was to construct a model that calculated the annual mean cumulative radon exposure concentrations, so that reliable conclusions could be drawn from environment-control group research. Radon causes chronic lung cancer. Therefore, the long-term measurement of radon exposure concentration, over one year, is needed in order to develop a health impact assessment for radon. Hence, based on the seasonal correction model suggested by Pinel et al.(1995), a predictive model of annual mean radon concentration was developed using the year-long seasonal measurement data from the National Institute of Environmental Research, the Korea Institute of Nuclear Safety, the Hanyang University Outdoor Radon Concentration Observatory, and the results from a 3-month (one season) survey, which is the official test method for radon measurement designated by the Korean Ministry of Environment. In addition, a model for evaluating the effective annual dose for radon was developed, using dosimetric methods. The model took into account the predictive model for annual mean radon concentrations and the activity characteristics of the residents

This study was performed to evaluate the asbestos exposure levels and to calculate excess lifetime cacer risks(ELCRs) in asbestos-containing buildings for maintenance and management. The range of airborne asbestos concentration of 33 buildings was 0.0018 ~ 0.0126 f/cc and one site exceeded indoor air-quality recommended limit 0.01 f/cc. And ELCRs based on US EPA IRIS(Integrated risk information system) model are 1.5E-06 ~ 3.9E-05 levels, and there was no site showed 1.0E-04 (one person per million) level or more, and 11 sites showed 1.0E-05 (one person per 100,000 people) level or more. To prevent the release of asbestos fibers, it needs operation and maintenance of asbestos-containing building materials, and there are some methods such as removal, repairment, enclosure and encapsulation. In conclusion, a risk-based air action level for asbestos in air is an appropriate metric for asbestos-containing building management.

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants derived from incomplete combustion of carbons and crude oil. In this study, we investigated the effects of benzo[a]pyrene (B[a]P), a representative PAHs on in vitro sex steroid hormone production and germinal vesicle breakdown (GVBD) using isolated oocytes of longchin goby (Chasmichthys dolichognathus) and chameleon goby (Tridentiger trigonocephalus). Oocytes in diameters of 0.8-0.9 (end vitellogenic stage) and 0.9-1.0 mm (germinal vesicle migratory stage) from longchin goby and 0.5 mm (fully vitellogenic stage) from chameleon goby were used. In GVBD assay, B[a]P at 10 nM stimulated GVBD in the oocytes of 0.8-0.9 mm from longchin goby. B[a]P at 1 nM stimulated GVBD in the oocytes with diameter 0.5 mm from chameleon goby. In steroid production from oocytes of longchin goby, B[a]P at 100 nM decreased testosterone (T) production, B[a]P at 1,000 nM increased estraiol-17 (J (E2) production and 10 and 100 nM increased -dihydroxy-4-pregnen-3-one () production in the oocytes with diameter 0.8-0.9 mm. B[a]P at 1,000 nM increased E2 production, 100 and 1,000 nM increased production in the oocytes with diameter 0.9-1.0 mm. In steroid production of oocytes from chameleon goby, B[a]P at 1,000 nM increased production. B[a]P at 10 nM increased production. In the ratio of to T (/T), B[a]P at 100 and 1,000 nM increased /T in the oocytes of longchin goby. B[a]P at 100 nM also increased /T in the oocytes of chameleon goby. Taken together, these results suggest that B[a]P have not only weak estrogenic effects but progestogenic effects on oocyte maturation.

This study evaluated the hazard caused by NO2, an oxidant generated in the process of welding. We compared hematological and biochemical parameters in workers who chronically inhale NO2 and office workers not exposed to NO2. NO2 exposure affected the hematological and biochemical parameters. Increasing NO2 concentrationincreased the number of leukocytes, while decreasing the number of erythrocytes. Blood urea nitrogen, creatinine, uric acid, and lactate dehydrogenase were increased, while total protein and triglycerides were decreased. The mean concentration of NOx(NO2-/ NO3-) in the serum of welders and the control group was 35.97±2.85 and 55.40±5.81 μmol/L, respectively. The difference was significant (p<0.05), although NO2- was not detected in the serum.

Indoor and outdoor nitrogen dioxide (NO2) concentrations were measured and compared with measurements of personal exposures of 95 persons in Seoul, Korea and 57 persons in Brisbane, Australia, respectively. Time activity diary was used to determine the impact on NO2 exposure assessment and microenvironmental model to estimate the personal NO2 exposure. Most people both Seoul and Brisbane spent their times more than 90% of indoor and more than 50% in home, respectively. Personal NO2 exposures were significantly associated with indoor NO2 levels with Pearson coefficient of 0.70 (p<0.01) and outdoor NO2 levels with Pearson coefficient of 0.66 (p<0.01) in Seoul and of 0.51 (p<0.01) and of 0.33 (p<0.05) in Brisbane, respectively. Using microenvironmental model by time weighted average model, personal NO2 exposures were estimated with NO2 measurements in indoor home, indoor office and outdoor home. Estimated NO2 measurements were significantly correlated with measured personal exposures (r = 0.69, p<0.001) in Seoul and in Brisbane (r = 0.66, p<0.001), respectively. Difference between measured and estimated NO2 exposures by multiple regression analysis was explained that NO2 levels in near workplace and other outdoors in Seoul (p = 0.023), and in transportation in Brisbane (p = 0.019) affected the personal NO2 exposures.