Background: Mercury, particularly in its methylmercury form, significantly affects neurological and developmental functions. In Gyeongsangbuk-do, Republic of Korea, blood mercury levels are elevated due to high fish consumption, especially shark meat. Vulnerable groups, such as pregnant women, are at increased risk as methylmercury can cross the placenta and accumulate in breast milk. This study aimed to investigate the risks of mercury exposure from shark meat consumption among young and middle-aged women in Gyeongsangbuk-do. Methods: The data of women aged 19–55 years from the 2018 Gyeongsangbuk-do Community Health Survey were included. Survey questions focused on frequency and amount of shark meat consumption, as well as pregnancy status, recent childbirth, and breastfeeding status. The Complex Sample Analysis was used to determine the prevalence and risk of overconsumption. Weekly mercury intake was calculated for respondents who reported their body weight, and the population size exceeding Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA) and Ministry of Food and Drug Safety (MFDS)’s threshold was estimated. Results: Regions where the consumption rate of shark meat exceeds the average for Gyeongsangbuk-do are found to be distributed in the southeastern part of the province. Population estimates revealed that approximately 9,895 women aged 19–55, including 255 who had breastfed in the past year, consumed shark meat exceeding the recommended intake. Based on the maximum recorded mercury concentration (8.93 μg/g), an estimated 2,645 women surpassed the JECFA’s mercury exposure threshold, while 845 exceeded the MFDS’s threshold. Conclusions In young and middle-aged women of Gyeongsangbuk-do, approximately 7.1% exceed the single intake limit, while up to 1.9% exceed the JECFA’s provisional tolerable weekly intake (PTWI) and 0.6% exceed the MFDS’s PTWI, suggesting considerable risk that warrants monitoring and guidance. More stringent advisory measures regarding shark meat consumption and updated standards on mercury concentration in shark meat are essential for young and middle-aged women in the province.

Objectives: Water discharged from waterlines in dental units can cause cross-infection among dental workers and patients by various mechanisms. Therefore, we analyzed the bacterial counts in the water of dental unit chair waterlines, according to waterline flushing and related factors. Methods: A total of 58 dental hospitals located in a metropolitan city participated in this study between September 2019 and January 2020. Water was collected from a high-speed handpiece and a three-way syringe of a dental unit chair and transported to the experimental lab within 4 hours;bacterial plating colony counting was performed after culturing for 72 hours. In addition, a survey was conducted with questions on the characteristics of hospitals, waterline flushing, and related factors, such as water purification systems, regular filter replacement, and backflow prevention equipment. Results: The bacterial count in the water of the dental handpiece and three-way syringe in the institutions that performed waterline flushing was lower than that in the institutions that did not (P<0.001). When waterline flushing was performed on dental handpieces, the bacterial count was found to be lower when regular filter replacement and backflow prevention equipment were combined. In addition, disinfection of waterlines had a significant effect on the bacterial count when performed together with waterline flushing. However, for the three-way syringe, when waterline flushing was performed, no factors significantly affected the bacterial count. Conclusions To reduce microbial contamination of dental water, flushing of dental unit waterlines combined with regular filter replacement, backflow prevention equipment, and disinfection of waterlines may be effective in dental hospitals.

Background: This study investigated the prevalence and associated factors of musculoskeletal pain among professional dancers who experienced a lapse in group practice due to coronavirus disease 2019. Methods: General characteristics, practice time, region of musculoskeletal pain due to injury using the visual numeric scale (VNS), and causative motion were surveyed among professional dancers. Pain of VNS 0 to 3 was categorized as “no or minor,” 4 to 6 was categorized as “moderate,” and 7 to 10 was categorized as “severe.” The causal motions of musculoskeletal pain were analyzed according to body region. Factors other than motion associated with pain were also analyzed. Results: In total, 368 participants were included. In the univariate analysis, age and practice time were positively associated with “moderate” pain. Practice time, dance experience, and postural accuracy were positively associated with “severe” pain, as was performing Korean traditional dance. In the multivariable analysis, practice time, group practice, and age were positively associated with pain of VNS 4 to 10, and practice time, group practice, and Korean traditional dance were positively associated with pain of VNS 7 to 10. Conclusion Among the factors related to dancer training, practice time, group practice, and dance type affect the occurrence of pain.

Objective: Assault in the emergency room can lead to a decrease in the quality of the entire emergency medical system due to the functional deterioration and increased fatigue of the medical staff. This research tried to identify and analyze the characteristics of assault against emergency medical technicians (EMTs) working in the emergency room and establish the factors related to poor post-assault-exposure response. Methods: In this multicenter study, we conducted a survey of EMTs working in the emergency rooms. Response after assault was measured by Likert 5-point scale; the data of the participants were divided based on the median score. The demographic characteristics, hospital preparedness, and the characteristics of the assault were analyzed. Afterwards, the data of the risk factors for poor post-assault-exposure response were subjected to multivariable logistic analysis. Results: Of the 141 study participants, 84 (59.6%) were women. Most of them had experienced verbal violence (n=137, 97.2%) and physical threats (n=137, 92.2%), and 96 (68.0%) had experienced physical assault in the past year. The results of the multivariable logistic regression analysis revealed that female sex (adjusted odds ratio [aOR], 6.152; 95% confidence interval [CI], 2.687-14.120) and the increase in the number of physical assaults (aOR, 1.160; 95% CI, 1.036- 1.298) were associated with a poor response. Conclusion Considering the importance of the EMTs in the emergency medical system and the potential adverse effects on the status of their health and services, the provision of appropriate support to female EMTs and the active intervention for attenuation of physical assault escalation in case of aggressive situations is needed. Our present results can be used for the identification and resolution of the underlying causes of these problems.

Background: In the early stage of the coronavirus disease 2019 (COVID-19) epidemic, small- and mid-sized enterprises (SMEs) may be an important transmission consideration. The study aimed to identify the pattern of COVID-19 prevention measures during the outbreaks in Daegu and Gyeongsangbuk-do at the early stage of COVID-19. Moreover, we investigated whether SME size and past experiences affected the preventive measures implemented in the region. Methods: A survey detailing the general characteristics and implementation of 12 preventive activities was conducted in 122 SMEs in Daegu and Gyeongsangbuk-do. The survey was analyzed by size and operation period. Results: The study subjects consisted of 53 (43.4%) workplaces with 1–5 employees, 50 (40.9%) workplaces with 6–30 employees, and 19 (15.6%) workplaces with 31–49 employees. The lowest three items among those surveyed were ‘symptomatic workers to stay home for 3–4 days’ (17.2%), ‘work remotely’ (18.9%), and ‘video meetings’ (20.5%). There were significant differences in the rate of several preventive measures implemented. The larger sized SMEs, the higher the number of implementations (p < 0.01). The operation period had no significant relationship with the implementation of preventive measures. The same pattern was observed in multiple generalized linear regression with covariate adjustment. Conclusion Preventive measures among SMEs with fewer than 50 employees were identified. Even within SMEs, a gap in preventive measures according to size was confirmed. To prevent the spread of infection and protect workers' right to health, different support for different sized SMEs is necessary.

Background: High concentrations of mercury intake from seafood are known to cause various side effects in humans, including on the nervous system. Various studies have reported the effects of mercury concentrations in humans; however, the association between dyslipidemia, a cardiovascular disease risk factor, and mercury remains controversial.Therefore, this study aimed to investigate the association between mercury accumulation and cholesterol concentrations in a Korean population. Methods: We analyzed data of a sample of 3,228 respondents obtained from the Korean National Environmental Health Survey cycle 3, surveyed between 2015 and 2017, to determine how lipid profiles changed according to the blood mercury concentrations (BHg) and urine mercury concentrations (UHg). Multiple regression analysis was used to determine the effects of mercury concentrations among various factors affecting blood cholesterol levels. Results: The arithmetic mean (AM) of BHg was 2.91 (2.81–3.02) μg/L, and the geometric mean (GM) was 2.71 (2.59–2.85) μg/L. The AM of UHg was 0.52 (0.48–0.56) μg/L, and the GM was 0.35 (0.33–0.38) μg/L. Lipid profiles were more related to the BHg than to the UHg. Total cholesterol (total-C), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels increased significantly as BHg increased in males, and total-C, triglyceride, and LDL-C levels increased significantly in females. Multiple regression analysis indicated that BHg were significantly associated with total-C, HDL-C, and LDL-C levels. Conclusions We found an association between mercury exposure and the risk of dyslipidemia; however, further studies are required to elucidate a causal association.

BACKGROUND: Although unusually high levels of blood mercury have been reported in the North Gyeongsang Province (Gyeongsangbuk-do), mercury contents from shark meat distributed in this region have not been assessed yet. Thus, this study aims to identify the hazard by evaluating the mercury contents of the shark meat sold in the traditional market of Gyeongsangbuk-do. METHODS: The shark meat in the form of muscle meat was obtained from 15 traditional markets of Gyeongsangbuk-do in the summer and winter of 2013. Out of 105 samples in total, 49 were collected in the summer and 56 in the winter. The total mercury concentration was measured by the combustion-gold amalgamation method using an automatic mercury analyzer (Milestone DMA-80, Milestone). RESULTS: The average mercury concentration of shark meat was 2.29 ± 1.77 µg/g, ranging between 0.06–8.93 µg/g with a geometric mean of 1.44 µg/g, which is higher than those reported in many countries. The mercury concentration in 77 of 105 shark meat samples exceeded 1 µg/g. Mercury concentration ranged between 0.09–8.93 µg/g (geometric mean: 1.45) in the summer and 0.06–6.73 µg/g (geometric mean: 1.48) in the winter. CONCLUSIONS Shark meat sold in the market contained a substantial amount of mercury. This suggests that it is difficult to reduce mercury intake by simply strengthening the standard level of mercury concentration in shark meat. Therefore, it is need to communication and awareness programs with consumers about hazardous effects of mercury inherent in shark meat.

BACKGROUND: In firefighters, smoking management is important because they are exposed to various harmful substances in their occupational environment. Accurate surveys of smoking status are essential to control tobacco use. The main disadvantage of self-report questionnaires, which are commonly used for investigating smoking status, is the possibility that the subjects' response are invalid. If the validity of firefighters' answers on smoking questionnaires is not adequate, different methods will be needed for investigating smoking status in firefighters. METHODS: This study was conducted on 445 male firefighters from 9 fire stations in Daegu (the city in South Korea) who visited a medical institution for medical checkup in 2016. The urine cotinine test strip (DCT-102; CLIAwaived Inc., cut-off value = 200 ng/mL) was used to classify the actual smoking status and to assess the validity of self-reported smoking status on questionnaires. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the smoking questionnaires were analyzed. Subjects testing positive in the urine cotinine test (assumed the actual current smokers) were selected. The frequency at which actual current smokers were misclassified as current non-smokers by the questionnaire was calculated. Subjects' characteristics were analyzed for possible association with any discrepancy between self-reported smoking status and urine cotinine test results. RESULTS: The smoking rates among firefighters surveyed using the smoking questionnaire and the urine cotinine test were 22.47% and 51.24%, respectively. Of the all subjects, 29.66% (n = 132) were misclassified. The sensitivity of the smoking questionnaire was 42.98%, the specificity was 99.08%, the PPV was 98.00%, and the NPV was 62.32%. In the 228 subjects classified as current actual smokers by the urine cotinine test, 57.02% (n = 130) were misclassified on the questionnaire. The misclassification rate increased with age. The degree of misclassification also increased when subjects had a history of disease. CONCLUSIONS In present study, the validity of the smoking questionnaire for firefighters was not suitable for investigating smoking status due to low sensitivity. To increase the validity of smoking status monitoring in firefighters, consideration of the various factors like survey environment, subjects' characteristics, and occupational factors is needed.

Gyeongsangbuk-do ; Korea ; Meat ; Methods ; Sharks

Cotinine ; Daegu ; Firefighters ; Fires ; Humans ; Male ; Sensitivity and Specificity ; Smoke ; Smoking ; Tobacco Use