• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2459-2465
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• 2012

Background: Numbers of epidemiological studies assessing residential radon exposure and risk of lung cancer have yielded inconsistent results. Methods: We therefore performed a meta-analysis of relevant published case-control studies searched in the PubMed database through July 2011 to examine the association. The combined odds ratio (OR) were calculated using fixed- or random-effects models. Subgroup and dose-response analyses were also performed. Results: We identified 22 case-control studies of residential radon and lung cancer risk involving 13,380 cases and 21,102 controls. The combined OR of lung cancer for the highest with the lowest exposure was 1.29 (95% CI 1.10-1.51). Dose-response analysis showed that every 100 Bq/$m^3$ increment in residential radon exposure was associated with a significant 7% increase in lung cancer risk. Subgroup analysis displayed a more pronounced association in the studies conducted in Europe. Studies restricted to female or non-smokers demonstrated weakened associations between exposure and lung cancer. Conclusions: This meta-analysis provides new evidence supporting the conclusion that residential exposure to radon can significantly increase the risk of lung cancer in a dose-response manner.

• Journal of Environmental Health Sciences
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• v.37 no.2
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• pp.94-101
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• 2011

Objectives: The purpose of this study is to evaluate the noise exposures of firefighters according to their time-dependent activity patterns. Methods: Personal exposure levels were measured for six days and nights using noise dosimeters; three days and nights for on-duty tasks, the other days and nights for off-duty activities. Results: The total amount of time spent in the workplace was 13,677 min (67%), outside areas 4,833 min (23%), in transit 1,002 min (5%), and other indoor area 807 min (4%) during a working period. However, during off-days they spent 10,858 min (76%) at home, 1,382 min (10%) outdoors, 1,225 min (9%) other indoors, and 493 min (3%) in transit. As a result of individual exposure levels, TWA did not exceed 90 dBA of the occupational exposure limit for the majority of the firefighters, whereas the levels of Lmax were 119 dBA, which were higher than the noise levels of firefighters in USA. Sometimes during dispatching the levels of Lpeak exceeded the ACGIH exposure standard (140 dBC). The Leq levels in transit were higher than the levels in home and other indoors even though the activity time is short. Conclusions: This paper characterized the noise exposure patterns of firefighters in Korea. We suggest that special noise sources, including sirens and speaker phones, should be readjusted to reduce noise exposure.

• Safety and Health at Work
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• v.14 no.3
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• pp.279-286
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• 2023

Background: This study aimed to evaluate the association between exposure to occupational hazards and the metabolic syndrome. A secondary objective was to analyze the additive and multiplicative effects of exposure to risk factors. Methods: This retrospective cohort was based on 31,615 health examinees at the Pusan National University Yangsan Hospital in Republic of Korea from 2012-2021. Demographic and behavior-related risk factors were treated as confounding factors, whereas three physical factors, 19 organic solvents and aerosols, and 13 metals and dust were considered occupational risk factors. Time-dependent Cox regression analysis was used to calculate hazard ratios. Results: The risk of metabolic syndrome was significantly higher in night shift workers (hazard ratio = 1.45: 95% confidence interval = 1.36-1.54) and workers who were exposed to noise (1.15:1.07-1.24). Exposure to some other risk factors was also significantly associated with a higher risk of metabolic syndrome. They were dimethylformamide, acetonitrile, trichloroethylene, xylene, styrene, toluene, dichloromethane, copper, antimony, lead, copper, iron, welding fume, and manganese. Among the 28 significant pairs, 19 exhibited both positive additive and multiplicative effects. Conclusions: Exposure to single or combined occupational risk factors may increase the risk of developing metabolic syndrome. Working conditions should be monitored and improved to reduce exposure to occupational hazards and prevent the development of the metabolic syndrome.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.32 no.1
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• pp.1-9
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• 2022

Objectives: The purpose of this study is to evaluate exposure characteristics of lead using data from the domestic occupational exposure literature. Methods: Occupational airborne exposure data on lead reported in the domestic literature from 1981 to 2018 were collected and re-analyzed. The exposure levels in the data were expressed as an estimated arithmetic mean and a weighted arithmetic mean (WAM) of the number of samples. Lead exposure characteristics were analyzed by industry, process, and year. Results: From a total of 14 documents, 8,305 airborne lead measurements for 17 industries were identified, and the WAM concentration in eight industries exceeded the occupational exposure limit of 50 ㎍/m³. Three industries (battery manufacturing, lead smelting, and litharge manufacturing) accounted for 95% of the total data, and exposure trends could be confirmed over 10 years. Exposure levels continue to decrease in all three industries. Conclusions: Considering the distribution outlook of lead and lead compounds, the main management targets are lead storage battery manufacturing and secondary smelting for lead regeneration.

• Journal of Environmental Health Sciences
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• v.35 no.6
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• pp.447-453
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• 2009

Cycling has been lately recommended as an alternative commuting mode because it is believed to be good for health and the environment. However, the exposure to environmental pollutants, such as fine particulates, could be a potential problem for cycling in urban environments. In this study, we compared commuters' $PM_{10}$ exposure using the different transportation modes of bicycle and bus. When a bicycle was used as a commuting mode, the additional $PM_{10}$ exposure due to transportation was about 3.5 times higher than that when using a bus. The difference of additional $PM_{10}$ exposures by cycling and bus was statistically significant (p<0.01). The $PM_{10}$ exposure during cycling was significantly correlated with atmospheric $PM_{10}$ concentration (r=0.98, p<0.01) and its correlation coefficient was higher than that of bus (r=0.55, p<0.05). The results of this study demonstrated that the main reasons of higher $PM_{10}$ exposure when using the bicycle as the mode of transport were its vicinity to road traffic and routes that were unavoidably close to road traffic. Bicycle commuting along the road side may not be good for health. Exclusive bicycle lanes away from road traffic are recommended.

• Journal of Environmental Health Sciences
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• v.35 no.6
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• pp.461-467
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• 2009

Exposure analysis is a critical component of determining the health impact of pollutants. Global positioning systems (GPS) could be useful in developing time-location information for use in exposure analysis. This study compares four low cost GPS receivers with data logging capability (Garmin 60, Garmin Forerunner 201, GeoStats GeoLogger and Skytrx minitracker MT4100) in terms of accuracy, precision, and ease of use. The accuracy of the devices was determined at two known National Geodetic Survey points. The coordinates logged by the devices were compared when the devices were carried while walking and driving. The Garmin 60 showed better accuracy and precision than the GeoLogger when they were placed at the geodetic points. The Forerunner and Skytrx did not record when they were kept stationary. When the subject wore the devices while walking, the location of the devices differed by about 8 m on average between any two device combinations involving the four devices. The distance between the coordinates logged by the devices decreased when the devices were carried with their antennas facing the sky. All the devices showed similar routes when they were used in a car. All the devices except the Forerunner had satisfactory signal reception when they were worn and when they were carried in the car. The GeoLogger is less comfortable for the subject because of specific wearing requirements. This evaluation found that the Garmin 60 and the Skytrx may be useful in personal exposure analysis studies to record time-location data.

• Korea Journal of Hospital Management
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• v.21 no.1
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• pp.51-61
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• 2016

This study attempted to investigate how mass media marketing of a hospital influences patient volume. Additionally, the association of patient volume with exposure time and the type of mass media was examined. Data from a university hospital in Bundang (from January 2014 to November 2014) were used. Degree of physicians' mass media marketing was measured by the number of media exposure. Linear mixed model for repeated measures data was run to identify the associations between the number of media exposure and patient volume. First, the number of hospital physician's mass media exposure and new patients and the first visit patients were positively associated. Second, broadcasting media which has relatively significant in patient volume is TV programs such as cultural programs and news. Third, hospital physicians with higher ranks who were exposed to press media receive more patient appointment. Also, nonsurgical hospital physicians who were exposed to press media receive more patients. Fourth, medical treatment activities for hospital staff who hold the rank of Professor in case of making an appearance at press media have relatively increased. Hospital physician's media exposure, particularly TV programs, was significantly related to patient volume for outpatients.

• Environmental Analysis Health and Toxicology
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• v.5 no.3_4
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• pp.47-56
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• 1990

Smoking damages nonsmoker's health who have been exposed to passive smoking as well as smoker's own health. Passive smoking can cause serious health damage to particular groups, such as the old aged, children and pregnant women. The purpose of this study is to investigate the relationship between nicotine concentrations in environmental tobacco smoke (ETS) and urinary cotinine concentrations of nonsmokers exposed to ETS, and to provide basic information related to health risk assessment. The results of this study were summarized as follows: 1. When 180 cigarrette were smoked during S hours (high concentrations exposure) in 132 m$^3$chamber, mean concentrations of nicotine in ETS showed 263.52 $\mu\textrm{g}$/m$^3$${\pm}$51.93. When 45 cigarretts were smoked (low concentrations exposure), it was 69.43${\pm}$8.96 $\mu\textrm{g}$/m$^3$. 2. The urinary cotinine concentrations of each times (0, 2.5, 5, 17 and 24 hours) in nonsmokers ranged from 0.27∼12.52 ng/ml in high concentrations exposure and 0.22∼2.28 ng/ml in low concentrations exposure. Mean while the total urinary cotinine concentrations during 24 hours ranged from 11.62∼31.65 ng/ml in high concentrations exposure and 3.45∼5.64 ng/ml in low concentrations exposure. 3. The correlation equation and coefficient between cotinine concentrations in nonsmokers' urine (y) and nicotine concentrations in ETS (x) was y=0.421+0.0171x and 0:875 (p<0.01) respectively, 4. The quantity of nonsmokers' smoking exposure by passive smoking can be assumed as based on the estimation of nicotine concentrations in ETS by measuring cotinine concentrations of nonsmokers' urine.

• Journal of Environmental Health Sciences
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• v.42 no.1
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• pp.1-9
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• 2016

Objectives: Personal exposure to air pollution is affected by contact over time and by location. The purpose of this study was to determine the relationship between personal exposure to $PM_{2.5}$ and the time-activity patterns of the elderly in urban and rural areas. Methods: A total of 44 elderly participants were recruited for a 24-hour $PM_{2.5}$ personal exposure measurement. Twenty-four were from Seoul (urban area) and 20 were from Asan (rural area). Energy expenditure and spatiotemporal positioning were monitored through $PM_{2.5}$ measurement. Spearman correlation analysis was conducted to determine the relationship between $PM_{2.5}$ and time-activity pattern. Results: Daily average $PM_{2.5}$ personal exposures were $19.1{\pm}9.7{\mu}g/m^3$ in Seoul and $29.1{\pm}16.9{\mu}g/m^3$ in Asan. Although outdoor exposure was higher in Seoul than in Asan, residential indoor exposure was higher in Asan than in Seoul. Higher $PM_{2.5}$ personal exposure in Asan could be explained by longer time in residential indoor environments and higher indoor $PM_{2.5}$ concentrations. Seoul elderly had higher energy expenditure, which may be due to the use of mass transportation. Conclusion: Personal exposure to $PM_{2.5}$ was higher among Asan elderly than Seoul elderly because of high residential indoor concentrations and longer residential time. Lack of energy spent and higher personal exposure to $PM_{2.5}$ might have led to higher risk among the Asan elderly.

• Journal of Yeungnam Medical Science
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• v.28 no.1
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• pp.45-53
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• 2011

Background: Increasing numbers of young people go to clubs. In Korea, however, no studies have been conducted regarding the exposure of club patrons to secondhand smoke. The present study was conducted to evaluate the degree of club customers' exposure to secondhand smoke. Methods: The study subjects included 10 male and 12 female non-smokers. The investigational site was a club located in Daegu. Urine samples were collected before exposure to secondhand smoke in the club and 6 hours after a 3-hour exposure. The urine cotinine levels were measured via the LC -MS/MS method. A survey was conducted to collect data regarding the subjects' smoking experiences and the degree of exposure to secondhand smoke in their daily lives. Results: The average urine cotinine level increased from 1.09 ${\mu}g/L$ to 5.55 ${\mu}g/L$ ($p$<0.05). No significant difference existed in the change in urine cotinine level between the male and female subjects. In addition, there was no significant difference in the change in urine cotinine level by the degree of exposure to secondhand smoke in daily life. Conclusions: The average urine cotinine level in all the subjects significantly increased after exposure to secondhand smoke. This is the first study on exposure to secondhand smoke in clubs; these results can be used to craft measures that reduce exposure to secondhand smoke in public places, such as clubs.