Although acute occupational poisonings are very rare officially, it seems that there are a considerable number of unreported cases seen from non-intentional poisoning cases of the national injury and poisoning survey on discharged patients. Establishing a proper national surveillance system for acute occupational poisonings is needed. It is difficult for clinical physicians to diagnose acute occupational poisonings appropriately because the victims who usually are not mentally alert can not provide the information on the workplace hazard. Consulting a specialist of occupational and environmental medicine may help to reveal the cause of poisoning. Furthermore, reporting to the public organization such as workers health center and Korea occupational safety and health is helpful to prevent additional injuries.
Environmental Medicine ; Humans ; Korea* ; Occupational Health ; Poisoning* ; Specialization

BACKGROUND: Methyl alcohol poisoning has been mainly reported in community. Two cases of methyl alcohol poisoning occurred in a small-sized subcontracted factory which manufactured smartphone parts in Korea. CASE PRESENTATION: One young female patient presented with dyspnea and visual disturbance. Another young male patient presented with visual disturbance and myalgia. They treated with sodium bicarbonate infusion and hemodialysis for metabolic acidosis. In addition, he received ethyl alcohol per oral treatment. Her and his urinary methyl alcohol concentration was detected as 7.632 mg/L, 46.8 mg/L, respectively, although they were treated hemodialysis. Results of the working environment measurement showed that the concentration of methyl alcohol (1030.1–2220.5 ppm) in the air exceeded the time weighted average (200 ppm). They were diagnosed with optic neuropathy due to methyl alcohol poisoning and still have visual impairment. CONCLUSIONS: Workers who hired as dispatched employees in a small-sized subcontracted factory were exposed to high concentrations of methyl alcohol. The workplace had poor ventilation system. In addition, workers did not wear proper personal protect equipment. Working environment measurement and annual chekups for workers were not performed. They were in a blind spot to occupational safety and health. More attention is needed to protect vulnerable workers’ health.
Acidosis ; Aluminum* ; Dyspnea ; Ethanol ; Female ; Humans ; Inhalation* ; Korea ; Male ; Methanol* ; Myalgia ; Occupational Health ; Optic Disk ; Optic Nerve Diseases ; Poisoning ; Renal Dialysis ; Smartphone ; Sodium Bicarbonate ; Ventilation ; Vision Disorders

Occupational hazards of firefighting and rescue works include frequent exposure to emergencies and life-threatening situations. These stressful work conditions of being constantly under pressure and exposed to potentially traumatic events put them at higher risk of developing posttraumatic stress disorder (PTSD), compared to the general population. PTSD is a potentially debilitating mental disorder, due to persistent intrusive thoughts, negative alterations of mood and cognition, hypervigilance, avoidance of similar situations and reminders, and re-experiences of the traumatic event. Previous studies have shown a relatively high prevalence of PTSD among firefighters, indicating the need for a systematic approach of early detection and prevention. Therefore, a critical review of the current literature on PTSD in firefighters would provide valuable insights into developing effective prevention and intervention programs. Literature indicated that there are risk factors of PTSD in firefighters, such as pre-existing depression, anxiety, sleep disorders, occupational stress, physical symptoms, and binge drinking, whereas social support and adequate rewards are protective factors. Although there are differences in the prevalence of PTSD across studies, partly due to various assessment tools utilized, different sample sizes, and sample characteristics, over one tenth of the firefighters were estimated to have PTSD. The current review warrants further investigations to precisely assess PTSD and co-morbid mental disorders, functional outcomes, and associated factors, and to develop evidence-based preventive and interventional programs to help firefighters with PTSD.
Anxiety ; Binge Drinking ; Cognition ; Depression ; Emergencies ; Firefighters* ; Humans ; Mental Disorders ; Prevalence ; Protective Factors ; Rescue Work ; Reward ; Risk Factors ; Sample Size ; Sleep Wake Disorders ; Stress Disorders, Post-Traumatic*

Background: Some working conditions may pose a higher physical or psychological demand to pregnant women leading to increased risks of pregnancy complications. Objectives: We assessed the association of woman's employment status and the industrial classification with obstetric complications. Methods: We conducted a national population study using the National Health Information Service database of Republic of Korea. Our analysis encompassed 1,316,310 women who experienced first-order live births in 2010–2019. We collected data on the employment status and the industrial classification of women, as well as their diagnoses of preeclampsia (PE) and gestational diabetes mellitus (GDM) classified as A1 (well controlled by diet) or A2 (requiring medication). We calculated odds ratios (aORs) of complications per employment, and each industrial classification was adjusted for individual risk factors. Results: Most (64.7%) were in employment during pregnancy. Manufacturing (16.4%) and the health and social (16.2%) work represented the most prevalent industries. The health and social work exhibited a higher risk of PE (aOR = 1.11, 95% confidence interval [CI]: 1.03–1.21), while the manufacturing industry demonstrated a higher risk of class A2 GDM (1.20, 95% CI: 1.03–1.41) than financial intermediation. When analyzing both classes of GDM, women who worked in public administration and defense/social security showed higher risk of class A1 GDM (1.04, 95% CI: 1.01, 1.07). When comparing high-risk industries with nonemployment, the health and social work showed a comparable risk of PE (1.02, 95% CI: 0.97, 1.07). Conclusion Employment was associated with overall lower risks of obstetric complications. Health and social service work can counteract the healthy worker effect in relation to PE. This highlights the importance of further elucidating specific occupational risk factors within the high-risk industries.

OBJECTIVES: Limited evidence is available regarding the impact of paternal occupation and its combined effect with maternal occupation on preterm birth. Therefore, we assessed the association of maternal and paternal occupations with preterm birth. METHODS: We used the national birth data of Korea between 2010 and 2020. Parental occupations were divided into 5 categories: (1) managers; (2) professionals, technicians, and related workers; (3) clerks and support workers; (4) service and sales workers; and (5) manual workers. A multinomial logistic regression model was used to calculate the adjusted odds ratios (aORs) of extremely, very, and moderate-to-late preterm births per occupational category considering individual risk factors. RESULTS: For the 4,004,976 singleton births, 40.2% of mothers and 95.5% of fathers were employed. Compared to non-employment, employment was associated with a lower risk of preterm birth. Among employed mothers, service and sales occupations were associated with a higher risk of preterm birth than managerial occupations (aOR, 1.06; 95% confidence interval [CI], 1.01 to 1.10 for moderate-to-late preterm births). The father’s manual occupation was associated with a higher risk of preterm birth (aOR, 1.09; 95% CI, 1.05 to 1.13 for moderate-to-late preterm) than managerial occupations. When both parents had high-risk occupations, the risk of preterm birth was higher than in cases where only the mother or neither of the parents had a high-risk occupation. CONCLUSIONS Paternal occupation was associated with preterm birth regardless of maternal employment and occupation and modified the effect of maternal occupation. Detailed occupational environment data are needed to identify the paternal exposures that increase the risk.

BACKGROUND: South Korea is one of the countries with the longest working hours in the OECD countries. The aim of this study was to evaluate the effect of working hours on depressive symptoms and the role of job stress factors between the two variables among employees in South Korea. METHODS: This study used data from the Korea Working Conditions Survey in 2014. Study subjects included 23,197 employees aged 19 years or older who work more than 35 h per week. Working hours were categorized into 35–39, 40, 41–52, 53–68, and more than 68 h per week. Depressive symptoms were assessed using the WHO’s Well-Being Index with a cut-off score of 13. We calculated prevalence ratios of depressive symptoms according to working hours using log-binomial regression. Through the percentage change in prevalence ratios, we identified the extent of the role of job stress factors that explain depressive symptoms. RESULTS: The risks of depressive symptoms were significantly higher in people who worked 35–39 h per week (PR: 1.09, CI: 1.01–1.18), 53–68 h/week (PR: 1.21, CI: 1.16–1.25), and more than 68 h/week (PR: 1.14, CI: 1.07–1.21) than 40 h/week, after adjusting for confounding variables. Job stress explained the effects of long working hours on depressive symptoms in about 20–40% of the groups working more than 40 h/week. Among the factors of job stress, social support was 10–30%, which showed the highest explanatory power in all working hours. Reward explained 15–30% in the more than 52 h working group, and reward was the most important factor in the working group that exceeded 68 h. CONCLUSIONS: We showed the working hours could be an independent risk factor for depressive symptoms in employees. To improve workers’ mental health, it is important to strengthen social support in the workplace, to provide adequate rewards as they work, and ultimately to regulate the appropriate amount of working hours.
Confounding Factors (Epidemiology) ; Depression ; Korea ; Mental Health ; Organisation for Economic Co-Operation and Development ; Prevalence ; Reward ; Risk Factors

Objectives: : We estimated the overall and age-specific percentages of the Korean population with presumed immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) as of April 2022 using the national registry. Methods: : We used the national coronavirus disease 2019 (COVID-19) infection and vaccination registry from South Korea, as described to define individuals with a previous history of COVID-19 infection, vaccination, or both, as persons with presumed immunity. Results: : Of a total of 53,304,627 observed persons, 24.4% had vaccination and infection, 58.1% had vaccination and no infection, 7.6% had infection and no vaccination, and 9.9% had no immunity. The SARS-CoV-2 Omicron variant emerged at a time when the presumed population immunity ranged from 80% to 85%; however, nearly half of the children were presumed to have no immunity. Conclusion : We report a gap in population immunity, with lower presumed protection in children than in adults. The approach presented in this work can provide valuable informed tools to assist vaccine policy-making at a national level.

National cohort data collected during the coronavirus disease 2019 (COVID-19) delta and omicron periods in Korea revealed a lower risk of severe infection in recipients of three doses of the COVID-19 vaccine (adjusted odds ratio [aOR], 0.05–0.08). The risk of death was reduced during the omicron period compared to the delta period (aOR, 0.75; 95% confidence interval, 0.67–0.84).

Methanol poisoning results in neurological complications including visual disturbances, bilateral putaminal hemorrhagic necrosis, parkinsonism, cerebral edema, coma, or seizures. Almost all reported cases of methanol poisoning are caused by oral ingestion of methanol. However, recently there was an outbreak of methanol poisoning via non-oral exposure that resulted in severe neurological complications to a few workers at industrial sites in Korea. We present 3 patients who had severe neurological complications resulting from non-oral occupational methanol poisoning. Even though initial metabolic acidosis and mental changes were improved with hemodialysis, all of the 3 patients presented optic atrophy and ataxia or parkinsonism as neurological complications resulting from methanol poisoning. In order to manage it adequately, as well as to prevent it, physicians should recognize that methanol poisoning by non-oral exposure can cause neurologic complications.
Acidosis ; Ataxia ; Brain Diseases, Metabolic ; Brain Edema ; Coma ; Eating ; Humans ; Korea ; Methanol* ; Necrosis ; Neurologic Manifestations ; Optic Atrophy ; Parkinsonian Disorders ; Poisoning* ; Renal Dialysis ; Seizures