• Environmental Analysis Health and Toxicology
• /
• v.21 no.4 s.55
• /
• pp.375-380
• /
• 2006

Endocrine disrupting chemicals (EDC) have been emphasized due to their threats in human health. Waste incinerator emission has been emphasized as a source of EDC including polychlorinateddibenzofurans(PCDD/F) and other carcinogenic polycyclic aromatic hydrocarbons (PAHs). Urinary 1-hydroxypyrene (1-OHP) has been used as an exposure biomarker for the PAHs. On the other hand, etheno-DNA adducts, e.g. 1, $N^6-ethenodeoxyadenosine({\varepsilon}dA)$, has been developed as an useful effective or response biomarker for carcinogenesis. Thus, I investigated association between urinary 1-OHP and ${\varepsilon}dA$ levels due to distance from an incinerator which was built more 10 years ago in the middle of a farm in P city. I designated the EDC-high and low exposed group due to distance from the incinerator, i.e. within 2.5km and $5.0{\sim}7.5km$ from the incinerator, respectively. The study subjects were age and sex-matched males and females (mean age, $61.3{\pm}9.6$ yrs; total 40 persons, male, 10; female, 10 for the each group). Urinary 1-OHP and ${\varepsilon}dA$ were analyzed with HPLC-FD and IP-HPLC-FD, respectively. As results, the distance from the incinerator was not associated with urinary 1-OHP nor ${\varepsilon}dA$ levels (p=0.43 and 0.82, respectively). On the other hand, urinary ${\varepsilon}dA$ levels were significantly higher in the hyperlipidemia group (N=10) than normal group (N=30). In conclusion, urinary 1-OHP nor ${\varepsilon}dA$ levels can not be suggested as an incinerator-related exposure nor effective biomarker. However, not only distance from the incinerator bot also systemic approaches including wind and soil contamination are required to assume exposure levels of incinerator-related EDC.

• Women's Health Nursing
• /
• v.26 no.2
• /
• pp.171-179
• /
• 2020

Purpose: This study aimed to investigate the effects of exposure to endocrine disruptors, burnout, and social support from peers on premenstrual syndrome (PMS) in nurses. Methods: This descriptive correlational study was conducted among 122 nurses under the age of 49 working at a university hospital. The participants answered self-report questionnaires. The data were analyzed using the t-test, analysis of variance, Pearson or Spearman correlation coefficients, and hierarchical multiple regression in IBM SPSS version 23.0. Results: The mean age of the nurses was 28.9 years. Of these nurses, 49.2% were working in a general ward, 24.6% in the intensive care unit, 14.8% in the emergency room, and 11.4% in an outpatient department. The explanatory power of the model was 38.3%, and it was statistically significant (F=11.74, p≤.001). Exposure to endocrine disruptors (β=0.32, p<.001) was the most powerful variable affecting PMS, followed by burnout (β=0.27, p=.001), working in the intensive care unit or emergency room (β=0.22, p=.003), family history of PMS (β=0.19, p=.009), and support from coworkers (β=-0.15, p=.043). Conclusion: Based on these findings, it is necessary to develop an intervention program to reduce the symptoms of PMS. Additionally, further studies are needed to develop and evaluate measures to minimize exposure to endocrine disruptors and burnout in order to alleviate PMS among nurses.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.33 no.4
• /
• pp.502-516
• /
• 2023

Objectives: The purpose of this study was to investigate occupational exposure to chemical and health status of foreign workers in Korea. Methods: The data were collected from survey of general characteristics, job-related characteristics, work environment-related characteristics of 180 foreign workers who have been working at manufacturing industries in Korea in 2022. The data were analyzed using Rex. Results: Among the 180 participants, men accounted for more than women by 71.7% (129 people). Most of them are Vietnamese or Filipino and most of them graduated from high school. 116 of all participants are exposed to chemicals at work. The most prevalence rate of subject's health problems were backache (61.0%), headache (53.9%), fatigue (68.0%). Controlling for age, the number of physical health problems experienced in the last year was associated with BMI (r=0.184, p=0.049), and the number of mental health problems experienced in the past year (r=0.056, p<0.001) and all showed significant positive (+) correlations. The number of chemical products handled under age control showed a significant negative (-) correlation with working hours (r=0.207, p=0.027) and BMI (r=0.214, p=0.022) and showed a significant positive (+) correlation. Conclusions: The results of this study provided the latest update on the health status of foreign workers in Korea. It is also the first survey to attempt to assess the exposure of foreign workers to chemicals.

• Journal of the Korean Geographical Society
• /
• v.38 no.3
• /
• pp.389-399
• /
• 2003

CRN (Cosmogenic radionuclide) methodology has been a versatile tool applicable to a wide range of geomorphology. This study was underiaken to ascertain the rate of erosion and exposure age of mountain-top detritus (tors and block streams) on Mt. Maneo by employing the concentrations of in-situ produced cosmogenic $^{10}$ Be and $^{26}$ Al from bedrock surfaces that are exposed to cosmic rays. The results suggest that tors on the summit were positioned here during the glacial period but no later than 65ka and block streams have been stabilized also since the last glacial period but no later than 38ka. The tors on the summit have been eroded at a slower rate (9m/Ma) than blocks on the hillslope (15m/Ma) since the initial abrupt exposure of each landform to cosmic rays, suggesting that there is a slight difference in the rate of erosion between the summit and the hillslope, and that the local relief between the two areas has been increased. When the $^{26}$ Al/$^{10}$ Be-$^{10}$ Be concentrations from samples are plotted in Lal's steady-state erosion island, one sample (from a for) has complex exposure histories, which can be explained by the occurrence of multiple chipping event of 5cm to 60cm in length on the surface of the rock.

• Proceedings of the Korean Environmental Health Society Conference
• /
• 2005.12a
• /
• pp.4-15
• /
• 2005

Methylmercury (MeHg) is an environmental pollutant with neurotoxic effects on the central nervous system. The major exposure route of MeHg to humans is via consumption of fish and shellfish which accumulate the chemical through the food web in an aquatic environment. Hair mercury level is an excellent marker for MeHg exposure. We have been conducting a survey on hair mercury contents among general populations from 14 districts to estimate the current Japanese MeHg exposure level. Total mercury levels of all hair samples collected (12923 in total) were analyzed by the oxygen combustion-gold amalgamation method using an atomic absorption mercury detector. Multiple regression analysis revealed that mercury levels were significantly correlated with several covariates, such as sex, age, the amount of daily intake of total fish/shellfish, a preference for certain fish such as tuna or bonito, and artificial waving. The geometric means for the population without artificial waving were 2.47 and 1.65 ${\mu}g/g$ for males (n = 5623) and females (n = 3470), respectively. Hair mercury levels varied with age, and the variations were more significant in males. Since the difference between sexes was not evident at younger ages, some hormonal control might also be involved in the mercury uptake by human hair. The average mercury levels in our hair samples varied among the sampling districts. Tuna is a major carnivorous fish with high mercury accumulations that is often consumed in Japan. The amount of fish consumption and the preference rate far tuna would appear to be responsible far the regional variation in hair mercury levels in Japan. Recently, a provisional tolerable weekly intake (PTWI) of MeHg was revised by 61st JECFA to 1.6 ${\mu}g/kg/week$, which was about half that of the Japanese standard, and corresponded to a hair level of 2.2 ppm. The distribution of hair mercury levels in Japanese populations in the present study indicated that 25% of the Japanese females of child-bearing age were estimated to be exposed to MeHg over the PTWI level. This would reflect the high Japanese consumption of marine products. However, not only mercury contamination, but also the nutritional benefit may have to be considered when discussing the risk involved in the current level of fish and shellfish consumption in Japan.

• Journal of Environmental Health Sciences
• /
• v.48 no.6
• /
• pp.315-323
• /
• 2022

Background: Socioeconomical disadvantaged communities are more vulnerable to environmental chemical exposure and associated health effects. However, there is limited information on chemical exposure among vulnerable populations in Korea. Objectives: This study investigated chemical exposure among underprivileged populations. We measured urinary metabolites of phthalates in urban disadvantaged communities and investigated their correlations with residential environment factors and relative socioeconomic vulnerability. Methods: Urine samples were collected from 64 residents in a disadvantaged community in Seoul. A total of eight phthalate metabolites were analyzed by liquid chromatography-mass spectroscopy. Analytical method used by the Korean National Environmental Health Survey (KoNEHS) was employed. Covariate variance analysis and general linear regression adjusted with age, sex and smoking were performed. Results: Several phthalate metabolites, namely monomethyl phthalate (MMP), monoethyl phthalate (MEP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) had higher levels than those reported in the adults of 4th KoNEHS. Notably, the MnBP level was higher in the lower socioeconomic group (geometric mean [GM]=47.3 ㎍/g creatinine) compared to non-recipients (GM=31.9 ㎍/g creatinine) and the national reference level (GM=22.0, 28.2 and 32.2 ㎍/g creatinine for adults, 60's and 70's, respectively.). When age, sex and smoking were adjusted, MEP and MnBP were significantly increased the lower socioeconomic group than non-recipients (p=0.014, p=0.023). The lower socioeconomic group's age of flooring were higher than non-recipients, not statistically significant. Conclusions: These results suggest that a relatively low income and aged flooring could be considered as risk factors for increased levels of phthalate metabolites in socioeconomic vulnerable populations.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.5
• /
• pp.593-600
• /
• 2024

This study aimed to investigate the extent to which media advertisements conducted by vocational colleges (such as SNS, banners, university information boards in high schools, terminal advertisements, local daily newspaper advertisements, and elevator video advertisements) influence the formation of a positive image of the college among incoming students. To this end, a total of 430 freshmen at K Vocational College in Jeonbuk were asked about the frequency of their exposure to the college's media advertisements for each type of media. Additionally, they were asked about the impact these advertisements had on forming a positive image of the college, and the results were analyzed accordingly. The frequency of exposure to the advertisements was measured to verify the exposure effect of the advertisements themselves. To determine the impact of the frequency of exposure to each type of media on the formation of a positive image, correlation analysis and regression analysis were conducted. The key findings are as follows: First, while there were differences in the frequently encountered media among different age groups, banners and SNS advertisements were the most frequently encountered when considering all age groups collectively. Second, regarding the impact of the frequency of exposure to each type of media on the formation of a positive image of the college, elevator advertisements had the most significant effect, followed by banner advertisements. The purpose of this study is to aid in the formulation of the college's promotional strategies, with the expectation that the college will achieve better results through more efficient advertising.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.25 no.1
• /
• pp.5-12
• /
• 2015

According to the analysis of special medical examination and work environment monitoring data, the rate of C1 and D1 on noise hazard exceeded 90 % among those of total hazardous factors. The rate of company exceeding noise exposure limit was also more than 90 %. The analysis result shows that main ages diagnosed with C1 and D1 was age of 50s. The majority scale company having workers diagnosed with C1 and D1 was the companies employing 5~49 workers. Types of industries which have a large number of companies exceeding noise exposure limit were automobile and trailer manufacturing, metal processing industry and primary metal manufacturing. A large number of work processes exceeding noise exposure limit were forming and processing work, cutting and bending work and grinding. To reduce the number of company exceeding noise exposure limit, the reduction counterplan should be focused on the type of industry and the work process which exceeded noise exposure limit frequently. However, the reduction counterplan is preemptively necessary to the type of industry and the work process which exceeded noise exposure limit consecutively if the purpose of reduction counterplan is not to merely reduce the number of company exceeding noise exposure limit but to abate workers' suffering from noise.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.20 no.2
• /
• pp.102-110
• /
• 2010

Personal exposure relies on characteristics of time activity patterns of the population of concern as human activities impact the timing, location, and level of personal exposure. The information about time spent in microenvironments plays a critical role for personal exposure to air pollutants. It is useful to determine the precise times of the day that the subjects are in certain locations or engaging in specific activities because exposure to some air pollutants can depend on temporal trends. This study investigated time activity pattern for workers of Korean population over 19 years old with 8,778 workers in weekday. The residential indoor times were 12 hours. Time activity was different by gender and the mean times stayed at home in weekday were 12.9 hours in female and 11.42 hours in male, respectively. The major factors on residential indoor time and workplace time were age, monthly income, occupation and industry type, work position, education, and gender. Considering shorter than those in other countries, Korean workers spent less time at home after the working hours. Determinants of time activity pattern need to be taken into account in exposure assessment, epidemiological analyses, exposure simulations, as well as in the development of preventive strategies. Since there are substantial difference of Korean worker activity pattern, this information can be critical for exposure assessment in Korea.

• Journal of Preventive Medicine and Public Health
• /
• v.43 no.6
• /
• pp.543-548
• /
• 2010

Objectives: The objective of this study was to calculate sample size and power in an ongoing cohort, Korea radiation effect and epidemiology cohort (KREEC). Method: Sample size calculation was performed using PASS 2002 based on Cox regression and Poisson regression models. Person-year was calculated by using data from '1993-1997 Total cancer incidence by sex and age, Seoul' and Korean statistical informative service. Results: With the assumption of relative risk=1.3, exposure:non-exposure=1:2 and power=0.8, sample size calculation was 405 events based on a Cox regression model. When the relative risk was assumed to be 1.5 then number of events was 170. Based on a Poisson regression model, relative risk=1.3, exposure:non-exposure=1:2 and power=0.8 rendered 385 events. Relative risk of 1.5 resulted in a total of 157 events. We calculated person-years (PY) with event numbers and cancer incidence rate in the nonexposure group. Based on a Cox regression model, with relative risk=1.3, exposure:non-exposure=1:2 and power=0.8, 136 245PY was needed to secure the power. In a Poisson regression model, with relative risk=1.3, exposure:non-exposure=1:2 and power=0.8, person-year needed was 129517PY. A total of 1939 cases were identified in KREEC until December 2007. Conclusions: A retrospective power calculation in an ongoing study might be biased by the data. Prospective power calculation should be carried out based on various assumptions prior to the study.