Representative levels of blood lead, mercury, and urinary cadmium in youth: Korean Environmental Health Survey in Children and Adolescents (KorEHS-C), 2012–2014

AbstractBackgroundThis study examined levels of blood lead and mercury, and urinary cadmium, and associated sociodemographic factors in 3–18 year-old Korean children and adolescents.Materials and methodsWe used the nationally representative Korean Environmental Health Survey in Children and Adolescents data for 2012–2014 and identified 2388 children and adolescents aged 3–18 years. The median and 95th percentile exposure biomarker levels with 95% confidence intervals (CIs) were calculated. Multivariate regression analyses were performed on log transformed exposure biomarker levels adjusted for age, sex, area, household income, and father’s education level. The median exposure biomarker levels were compared with data from Germany, the US, and Canada, as well as the levels of Korean children measured at different times.ResultsThe median levels of blood lead and mercury, as well as urinary cadmium were 1.23μg/dL, 1.80μg/L, and 0.40μg/L (95% CIs, 1.21–1.25, 1.77–1.83, and 0.39–0.41, respectively). The blood lead levels were significantly higher in boys and younger children (p<0.0001) and children with less educated fathers (p=0.004) after adjusting for covariates. Urinary cadmium level increased with age (p<0.0001). The median levels of blood mercury and urinary cadmium were much higher in Korean children and adolescents than those in their peers in Germany, the US, and Canada. Blood lead levels tended to decrease with increasing age and divergence between the sexes, particularly in the early teen years. Median levels of blood lead and urinary cadmium decreased since 2010.ConclusionSociodemographic factors, including age, sex, and father’s education level were associated with environmental exposure to heavy metals in Korean children and adolescents. These biomonitoring data are valuable for ongoing surveillance of environmental exposure in this vulnerable population

Effects of work-related factors on self-reported smoking among female workers in call centers: a cross-sectional study

Abstract Objectives This study conducted to investigate work-related factors in relation to smoking among women working in call centers in Gwangju, South Korea. Methods From 56 call centers (7320 employees), we selected 10 and conducted a survey using a structured questionnaire by randomly selecting 10% of workers from each center. A total of 387 subjects participated in this survey We analyzed for 375 respondents, after excluding men and those with missing responses. We analyzed the relationships of work-related factors such as emotional labor, workplace violence, employment type, annual salary, working hours, employment period with smoking, using multiple logistic regression analysis. Emotional labor and workplace violence were measured using the Korean Emotional Labor Scale (K-ELS) and Korean Workplace Violence Scale (K-WVS). Results The prevalence of current smoking among call center female workers was 13.6%. Univariate analysis showed that “Emotional disharmony and hurt”, “Experience of psychological and sexual violence from supervisors and co-workers” among items of K-ELS and K-WVS, working hours, annual salary correlated with smoking. After adjusting for emotional labor, workplace violence, employment type, annual salary, working hours, employment period, and age, only working hours show a significant association with smoking. Women who worked 40–49 h had 3.50 times (95% CI = 1.04–11.80) and worked more than 50 h had 8.68 times (95% CI = 1.89–39.78) greater odds of smoking as compared with women who worked less than 40 h. Conclusions Smoking was associated with working hours among female workers in call center. However, emotional labor and workplace violence did not show significant relationships with smoking

Prognostic value of apoptosis-related markers in urothelial cancer of the upper urinary tract

We investigated the expression of apoptosis-related markers and their association with the clinical outcomes of patients with urothelial carcinoma of the upper urinary tract. A total of 112 patients with urothelial carcinoma of the upper urinary tract that had surgery from March 1998 to July 2005 were included in the study. Tissue microarray slides were used for immunohistochemistry, and immunohistochemical staining was performed to investigate the association of apoptosis-related markers with clinical outcome. Apoptosis was confirmed by the TdT-mediated DUTP nick-end labeling method to obtain the apoptotic index. Survival analysis was performed according to the Kaplan-Meier method, and the Cox proportional hazard regression model was used to compare the relative influence of different prognostic factors. Among the 112 patients, 32 (28.6%) had altered expression of p53, 30 (26.8%) of bcl-2, 62 (55.4%) of bax, 27 (24.1%) of caspase-3, and 23 (20.5%) of survivin. The expression of p53 and caspase-3 was associated with the pathologic grade (P = .035 and P = .004, respectively). Altered expression of caspase-3 was associated with the pathologic stage (P = .016). The multivariate analysis showed that the expression of survivin (hazard ratio 2.91, 95% confidence interval 1.07-7.90, P = .036) and the apoptotic index (AI) (3.35, 1.06-10.56, P = .039), as well as the T and N stages (P = .043 and P = .010, respectively) were significantly associated with the disease-specific survival. Our results suggest that survivin expression and a high apoptotic index were poor prognostic factors for survival in patients with urothelial carcinoma of the upper urinary tract. These results may help to identify a subset of patients who require adjuvant therapy or closer follow-up

Lumbar intervertebral disc degeneration and related factors in Korean firefighters

OBJECTIVES: The job of firefighting can cause lumbar burden and low back pain. This study aimed to identify the association between age and lumbar intervertebral disc degeneration and whether the association differs between field and administrative (non-field) firefighters. METHODS: Subjects were selected using a stratified random sampling method. Firefighters were stratified by geographic area, gender, age and type of job. First, 25 fire stations were randomly sampled considering regional distribution. Then firefighters were stratified by gender, age and their job and randomly selected among the strata. A questionnaire survey and MRI scans were performed, and then four radiologists used Pfirrmann classification methods to determine the grade of lumbar intervertebral disc degeneration. RESULTS: Pfirrmann grade increased with lumbar intervertebral disc level. Analysis of covariance showed that age was significantly associated with lumbar intervertebral disc degeneration (p<0.05). The value of β (parameter estimate) was positive at all lumbar intervertebral disc levels and was higher in the field group than in the administrative group at each level. In logistic regression analysis, type of job was statistically significant only with regard to the L4-5 intervertebral disc (OR 3.498, 95% CI 1.241 to 9.860). CONCLUSIONS: Lumbar intervertebral disc degeneration is associated with age, and field work such as firefighting, emergency and rescue may accelerate degeneration in the L4-5 intervertebral disc. The effects of field work on lumbar intervertebral disc degeneration were not clear in discs other than at the level L4-5.ope