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Serum samples were collected from volunteers of various ages and both genders using a proportionate stratified sampling method, to assess the exposure of the general population in Busan, South Korea to perfluorinated compounds (PFCs). 16 PFCs were investigated in serum samples from 306 adults (124 males and 182 females) and one day composite diet samples (breakfast, lunch, and dinner) from 20 of the serum donors, to investigate the relationship between food and serum PFC concentrations. Perfluorooctanoic acid and perfluorooctanesulfonic acid were the dominant PFCs in the serum samples, with mean concentrations of 8.4 and 13 ng/mL, respectively. Perfluorotridecanoic acid was the dominant PFC in the composite food samples, ranging fromDL to 1.48 ng/g. PFC concentrations in the serum samples increased with the age of the volunteer, and were higher in males than in females, similar to the results of other studies. We confirmed from the relationships between questionnaire results and the PFC concentrations in the serum samples, that food is one of the important contribution factors of human exposure to PFCs. However, there were no correlations between the PFC concentrations in the one day composite diet samples and the serum samples, because a one day composite diet sample is not necessarily representative of a person's long-term diet and because of the small number of samples taken.

In this study, a statistical estimation of probable precipitation and an analysis of its return period in Busan were performed using long-term precipitation data (1973-2007) collected from the Busan Regional Meteorological Administration. These analyses were based on the method of probability weighted moments for parameter estimation, the goodness-of-fit test of chi-square (χ 2 ) and the probability plot correlation coefficient (PPCC), and the generalized logistics (GLO) for optimum probability distribution. Moreover, the spatial distributions with the determination of probable precipitation were also investigated using precipitation data observed at 15 Automatic Weather Stations (AWS) in the target area. The return periods for the probable precipitation of 245.2 and 280.6 mm/6 hr with GLO distributions in Busan were estimated to be about 100 and 200 years, respectively. In addition, the high probable precipitation for 1-, 3-, 6-, and 12-hour durations was mostly distributed around Dongrae-gu site, all coastal sites in Busan, Busanjin and Yangsan sites, and the southeastern coastal and Ungsang sites, respectively.

Although workplace asbestos concentrations (AC) have been reported several times, the past environmental AC are relatively poorly studied. Due to the harmful effects of the asbestos industry, production has moved from early industrialized countries (Japan), to late industrialized countries (Korea), and finally to industrializing countries (Indonesia). The purpose of this study was to determine current occupational exposure levels and evaluate neighborhood environmental exposure levels in an Indonesian asbestos textile factory through collaboration among three generation of industrialized countries. Asbestos concentrations were measured inside and outside of the factory and compared with simulated data. ACs in the factory were similar to those of 1980s and 1990s levels in the Korean factory that transferred the machines. Environmental ACs were dispersed according to wind direction. There were no significant differences between monitored and simulated data, and correlation coefficients between downwind, upwind, and middle wind directions were high, with some statistical significance. This study can be used to estimate past environmental ACs to understand the causality of asbestos related diseases. Because of the small sample size and specific weather conditions, a large-scale study of various asbestos exposure sources, including asbestos cement factories, shipyards, and mines, and various atmospheric conditions is required.

Objectives: Effects of aging and leisure time physical activity (LPA) might influence the effect of occupational physical activity (OPA) on risk for cardiovascular disease (CVD). This study was conducted to determine whether OPA affects CVD after controlling the effects of LPA and other risk factors for CVD such as job stress. Methods: Participants were 131 male Korean manual workers. Tests for heart rate variability (HRV) were conducted for five minutes in the morning at work. We defined OPA as the combined concept of relative heart rate ratio (RHR), evaluated using a heart rate monitor. Results: Whereas high OPA was not related to any HRV items in the younger age group, high OPA was associated with an increased number of low-value cases among all HRV items in older workers. Exercise had beneficial effects only in the younger group. After controlling for exercise and other risk factors, the odds ratios of the root-mean square of the difference of successive normal R-R intervals (rMSSD) and high frequency band power (HF) among the older age and high OPA group compared with the younger age and low OPA group were 64.0 and 18.5, respectively. Social support and shift work were independent risk factors in HRV. Conclusions: OPA in aging workers increases CVD risks. This study provides support for the need for protection of aging workers from physical work overload, and indicates the need for further study of optimal limits of OPA.