Background: Occupational diseases represent a significant global public health challenge, yet reliable data from transitioning economies remain limited. This study aimed to analyze newly confirmed occupational disease cases in Mongolia over a 50-year period (1975–2023), identifying long-term trends and the prevalence of leading disease categories. Methods: A retrospective, record-based study was conducted using quantitative data from 10,233 officially confirmed and compensated cases of occupational diseases resulting in an officially certified loss of labor capacity. Incidence rates per 100,000 workers were calculated for the 1992–2023 period. Leading diseases were classified by organ system, with focused analyses on respiratory diseases, occupational poisonings, and neurological disorders. Results: Dust- and particulate-induced respiratory diseases accounted for the largest proportion of cases (57.4%), followed by occupational neurological disorders (16.2%) and occupational poisonings (8.0%). From 1992 to 2023, incidence rates among male workers were consistently 3–7 times higher than those among female workers. Analysis of exposure duration showed mean durations of 13.6 ± 4.9 years for silicosis (J62) and 20.7 ± 10.7 years for inorganic substance poisoning (T57). While respiratory diseases were predominant historically, occupational neurological diseases demonstrated an increasing trend after 2015. Conclusions Occupational neurological disorders are showing an increasing trend in Mongolia, reflecting a shift in the national occupational disease pattern. However, as the registry is based on the national compensation framework, these findings likely reflect recognized cases rather than the true epidemiological incidence, suggesting potential underreporting. Strengthening surveillance beyond the compensation system and improving diagnostic capacity for a broader range of work-related conditions are essential for effective prevention and policy development.

Climate change is intensifying occupational heat exposure, posing risks not only for heat-related illness but also for sleep, which is essential for recovery, safety, and productivity. Heat-exposed workers are highly vulnerable due to prolonged exposure, limited access to cooling, and poor housing. This systematic review aimed to synthesise global evidence on how occupational heat exposure affects sleep quality among workers across different occupations and settings. A systematic review was conducted following Synthesis without Meta-Analysis (SWiM) guidelines. PubMed, Scopus, and Google Scholar were searched (2000–2025) for studies involving adult workers (≥18 years) reporting both heat exposure and sleep outcomes. The review was registered with PROSPERO (ID: CRD420251125735). Of 7,108 records screened, 11 studies met the inclusion criteria. Studies spanned Asia, Australia, North America, and global cohorts. Heat exposure consistently impaired sleep quality and duration. Using Pittsburgh Sleep Quality Index, Actigraphy, and self-reports, common complaints included difficulty falling asleep (64%), restlessness (54%), non-restorative sleep (54%), night sweats (36%), and reduced total sleep time (45%). Night-time temperatures above 25°C and high workplace wet bulb globe temperature values were strongly linked with reduced sleep efficiency and delayed sleep onset. Vulnerable groups included shift workers, petrochemical and steel labourers, women, older adults, and low-income workers in urban heat islands and poorly ventilated housing. Occupational heat exposure disrupts sleep, compounding daytime strain and creating a dual burden for workers. Integrating sleep into heat stress management through cooling interventions, better housing, and revised work–rest schedules is critical for workers well-being in a warming climate.

Background: The objective of this study was to establish criteria for designing health examination programs and selecting appropriate examination items for high-risk occupational groups and to apply these criteria specifically to female fishers. Methods: The first Delphi survey comprised five domains and 15 specific criteria for identifying relevant health screening items for high-risk occupations. The second survey included open-ended questions addressing inconsistencies identified in the first survey and sought suggestions for additional items. In the third Delphi survey, specific health screening items were proposed for female fishers, and experts directly evaluated these items according to the finalized selection criteria. Results: Twenty-eight experts participated in this study. The first and second Delphi rounds facilitated the finalization of selection criteria for health screening items, consisting of five domains: Domain 1, Priority of target disease; Domain 2, Applicability of early detection and intervention; Domain 3, Scientific evidence of medical test method; Domain 4, Acceptability of medical test method; and Domain 5, Effectiveness of examination. Content validity ratios for these criteria ranged between 0.429 and 1.000. Based on the established criteria, experts evaluated eight proposed screening items for female fishers in the third round of the Delphi survey. Bone density, bioelectrical impedance analysis, cardiovascular disease risk factors, and fundoscopy were evaluated as appropriate; however, no agreement was reached on the early detection and intervention areas for degenerative lumbar disease, knee osteoarthritis, and upper extremity disease, as well as on the effectiveness for upper extremity disease and chronic obstructive pulmonary disease. Conclusion This study successfully established comprehensive criteria for selecting diseases targeted by health examinations in high-risk occupational groups. The practical application of these criteria proved effective in assessing the appropriateness of specific health screening items.

Background: Lithium hydroxide (LiOH) is increasingly used in electric vehicle battery production; however, its health effects in the work environment remain underreported. This study characterizes the acute health effects on workers following accidental occupational exposure to LiOH at a Korean lithium plant in March 2024. Methods: We analyzed health effects from two LiOH exposure accidents on March 6 and 9, 2024, involving 50–100 kg powder spills. Two datasets were examined: acute symptoms from 115 workers who visited hospitals immediately after exposure, and a symptom severity survey from 474 workers conducted 2 weeks post-exposure. Workers were stratified by distance from the leak source (<10 m, 10–20 m, >20 m) and respirator use. Univariate general linear modeling was applied to analyze the relationship between symptom occurrence and both the distance from the exposure source and respirator use. Results: Among workers visiting hospitals immediately, local irritation symptoms predominated: sore throat (58.3%), cough (28.7%), and skin dermatoses (17.4%). Systemic symptoms included headache (45.2%), nausea (18.3%), chest tightness (12.2%), and dizziness (9.6%). Two-week follow-up revealed overall symptom improvement; severe cough decreased from 22.2% to 10.1%. However, despite general improvement, a significant portion of workers reported persistent respiratory issues, including cough (28.7%) and sputum production (31.0%). Symptom severity showed a significant dose-response relationship with proximity to the source (p < 0.001). While respirator use offered initial protection (p = 0.021), this effect was not statistically significant after 2 weeks. Conclusions Occupational LiOH exposure caused acute irritation and systemic symptoms, demonstrating immediate tissue damage consistent with its alkalinity and systemic toxicity upon absorption. As lithium battery production expands globally, these results emphasize the necessity for developing specific occupational exposure limits and medical surveillance guidelines for lithium compounds.

Background: Although the association between handgrip strength and glycemic control has been reported, studies conducted exclusively within specific occupational groups remain limited. To explore the association between handgrip strength and metabolic health in industrial settings, this study examined the relationship between relative handgrip strength and glycated hemoglobin (HbA1c) among male automobile manufacturing workers using vibration tools in South Korea. Methods: Using 66,212 occupational health examination records collected at Inha University Hospital between January 2024 and April 2025, a total of 3,365 workers with HbA1c and handgrip strength measurements were identified. After excluding duplicates (n = 1,536), female workers (n = 2), and records without Hb and estimated glomerular filtration rate, 1,823 male participants were included in the final analysis. Relative handgrip strength was calculated as the maximum value of bilateral grip strength divided by body mass index. Multiple linear regression analyses were conducted to assess the association between relative handgrip strength and HbA1c, adjusting for age, smoking status, alcohol consumption, current hypertension, current dyslipidemia, current hypoglycemic-agents use, family diabetes history, leisure-time physical activity, and resistance exercise. Results: Relative handgrip strength was inversely associated with HbA1c levels (B: –0.060; 95% confidence interval [CI]: −0.081 to −0.039; p < 0.001). The association was strongest among normoglycemic participants (B: −0.185; 95% CI: −0.305 to −0.065; p = 0.003). Effect size was reduced but significantly associated among individuals with prediabetes (B: −0.115; 95% CI: −0.180 to −0.050; p < 0.001) and further attenuated to a borderline significance in individuals with diabetes (B: −0.023; 95% CI: −0.050 to 0.003; p = 0.082). These findings indicate that greater muscle strength relative to body size is related to better glycemic control. Conclusions Handgrip strength was associated with HbA1c levels in industrial workers. This study suggests that handgrip strength may provide complementary information on metabolic health in occupational settings.

Background: Indoor firing ranges are globally recognized as high-risk settings for occupational and recreational lead exposure due to the use of lead-based ammunition and frequently inadequate ventilation systems. In Korea, however, public health surveillance and regulatory oversight have remained limited. This case series empirically demonstrates that in high-emission settings like indoor firing ranges, ventilation upgrades are insufficient. Source substitution with lead-free primer ammunition proved to be the only definitive intervention.Case presentation: In late 2023, an index case presenting with abdominal pain was found to have a blood lead level (BLL) of 55 μg/dL, prompting a government-mandated investigation. Nine male shooting instructors (tenure: 4–65 months) were subsequently identified with BLLs ranging from 38.2–73.2 μg/dL, while airborne lead concentrations (ALC) reached 0.51 mg/m³—10 times the occupational exposure limit (OEL: 0.05 mg/m³).During a 3-month closure to upgrade ventilation, workers received chelation therapy (CaNa₂EDTA and D-penicillamine), which reduced their BLLs to 3.2–25.7 μg/dL. However, 2 months after reopening, post-intervention ALC remained elevated at 0.0797 mg/m³, still exceeding the OEL, and BLLs rebounded to 16.2–53.3 μg/dL. A substitution strategy was then implemented, replacing lead-based ammunition with copper-clad, lead-free primer rounds. This intervention decreased ALC to <0.003 mg/m³ and lowered BLLs to 4.9–23.1 μg/dL. Despite the reduced airborne concentrations, several workers continued to exhibit BLLs around 20 μg/dL, suggesting subtle ongoing exposure and mobilization of bone-stored lead. Conclusions This cluster demonstrates that in environments where hazardous agents are continuously generated, such as indoor firing ranges, engineering controls alone, such as improved ventilation, may not provide adequate protection. Substitution—the most effective intervention within the hierarchy of controls—was essential for eliminating exposure. Furthermore, the toxicokinetics of bone lead in chronically exposed adults highlight the need for ongoing monitoring and cautious decision-making regarding treatment and return-to-work planning.

Background: Long working hours have been associated with adverse physical and mental health outcomes; however, evidence regarding their relationship with satisfaction with work environment remains limited, particularly when long working hours are defined using a specific daily threshold. This study examined the association between working ≥10 hours per day and satisfaction with work environment among Korean wage workers, focusing on the cumulative number of such workdays per month. Methods: This cross-sectional study analyzed data from the 7th Korean Working Conditions Survey. A total of 24,269 wage workers aged ≥18 years were included after excluding self-employed workers, unpaid family workers, shift workers, and respondents with missing data. Working ≥10 hours per day was categorized as 0, 1–9, and ≥10 days per month. Satisfaction with work environment was categorized as satisfied or dissatisfied. Multiple logistic regression analyses were conducted to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for dissatisfaction with work environment according to the number of long working days, adjusting for demographic and occupational characteristics. Results: Compared with workers who did not work ≥10 hours per day, those who worked 1–9 days and ≥10 days per month showed progressively higher levels of dissatisfaction with work environment. After adjustment for demographic and occupational factors, the odds of dissatisfaction with work environment were significantly higher among workers who worked ≥10 hours per day for 1–9 days per month (OR: 1.380; 95% CI: 1.145–1.665) and ≥10 days per month (OR: 2.106; 95% CI: 1.627–2.725), demonstrating a dose–response relationship. Conclusions Among the analytic sample of Korean wage workers included in this study, working ≥10 hours per day was associated with greater dissatisfaction with work environment, with a dose–response pattern according to the number of long working days per month.

Background: Perfluoroalkyl substances (PFAS) are used in various products, and PFAS have been detected in outdoor clothing. PFAS can be absorbed into the human body via oral ingestion, inhalation, and dermal contact. In this study, we examined the association between the frequency of using outdoor clothing and serum PFAS concentrations in the Korean population using data from cycle 4 (2018–2020) of the Korean National Environmental Health Survey. Methods: Data from 2,993 adult participants were analyzed. The participants were classified into low-concentration and high-concentration groups based on the 75th percentile concentration of serum PFAS. The use of outdoor clothing was categorized into three groups: non-use, <4 times a week, and ≥4 times a week. The odds ratio (OR) for serum PFAS levels associated with use of outdoor clothing was determined through logistic regression analysis, adjusted for demographic characteristics, health-related factors, PFAS-treated items, dietary factors, and ventilation time. Results: ORs for high serum PFAS were higher in groups using outdoor clothing compared to the non-user group. In males, the adjusted ORs for the < 4 times a week and ≥ 4 times a week outdoor clothing usage group were as follows: perfluorooctanoic acid (PFOA), 1.26 (95% confidence interval [CI]: 1.10–1.44) and 1.70 (1.40–2.07); perfluorohexanesulfonic acid (PFHxS), 1.49 (1.16–1.92) and 1.70 (1.22–2.37); and perfluorononanoic acid (PFNA), 1.34 (1.19–1.51) and 1.68 (1.38–2.05), respectively. In females, the respective ORs were as follows: PFOA 1.32 (95% CI: 1.19–1.46) and 1.53 (1.01–2.32); PFHxS, 1.46 (1.08–1.96) and 2.63 (2.10–3.29); PFNA, 1.38 (1.22–1.55) and 1.45 (1.07–1.96). Conclusions In adults, elevated serum PFAS levels were associated with increased frequency of using outdoor clothing.

Background: Hydrocarbon pneumonitis is typically self-limiting, and severe complications, such as lung abscesses, are rare. Here, we report the case of a seafarer who developed bilateral lung abscesses after aspirating an industrial cleaning solvent, highlighting the aggravating role of delayed medical care and improper first-aid measures in a maritime setting.Case presentation: A 46-year-old seafarer presented with dyspnea, 3 days after accidentally ingesting a hydrocarbon-based solvent that he mistook for water. Although he immediately spat out the fluid, he aspirated a small amount. His condition rapidly deteriorated to necrotizing pneumonia with bilateral lung abscesses, as confirmed by chest computed tomography. Despite empirical antibiotic therapy, the abscess worsened, necessitating a video-assisted thoracic surgery for drainage. The patient recovered after surgery and underwent a prolonged course of antibiotic therapy. Conclusions This case underscores the potential for life-threatening complications from industrial solvent aspiration, exacerbated by delayed medical care and forceful spitting. Strict workplace safety protocols, including the prohibition of storing chemicals in food containers to avoid confusion, and awareness about not inducing vomiting after ingestion, are essential to prevent such severe occupational injuries.

Background: Work-related musculoskeletal disorders (WRMSDs) remain a major cause of occupational disability and productivity loss worldwide. Traditional statistical methods have identified numerous associated factors; however, they often struggle to capture complex non-linear relationships and interactions across multiple domains of risk. Machine learning (ML) offers an alternative analytical approach for modelling such multidimensional relationships. Methods: Following the PRISMA 2020 guidelines (PROSPERO: CRD420250605234), literature searches were conducted in Web of Science, Scopus, and PubMed for studies published between 2020 and 2025. Eligible studies applied ML methods to identify factors associated with WRMSDs using cross-sectional study designs. Included studies were appraised using the Joanna Briggs Institute Critical Appraisal Checklist for analytical cross-sectional studies. Results: Ten studies met the inclusion criteria, representing workers from healthcare, transport, manufacturing, and service sectors across Asia, Africa, and Europe. Frequently applied ML algorithms included random forest, support vector machine, and artificial neural networks, demonstrating strong internal discriminative performance (area under the receiver operating characteristic curve: 0.80–0.99), although the absence of external validation in several studies suggests a potential risk of overfitting. Commonly identified factors included age, sex, awkward posture, vibration exposure, prolonged working hours, stress, and burnout. Psychosocial factors, including post-traumatic stress disorder, job stress, and depression, were ranked among the most influential predictors within ML models. Conclusions ML models demonstrate strong capability in discriminating WRMSDs risk and identifying multidimensional risk factors compared with traditional statistical approaches. These models highlight complex interrelationships between ergonomic and psychosocial exposures. Future research should incorporate external validation, objective exposure measurements, and standardized ML reporting frameworks to enhance methodological transparency and generalizability.