Occupational Stress and Its Adverse Health Effects Among Metal Mining Workers: A Cross-Sectional Study in China

Objective: This study investigates the prevalence of occupational stress among metal mining workers in China and its impact on depressive symptoms, insomnia, and work-related musculoskeletal disorders (WMSDs), while also exploring insomnia as a potential mediator and identifying effect modifiers. Methods: A cross-sectional survey of 1,130 metal mining workers in China was conducted from June to November 2023. Occupational stress, depressive symptoms, insomnia, and WMSDs were assessed using validated scales. Logistic regression models examined associations between occupational stress and health outcomes, adjusting for key covariates. Subgroup and mediation analyses assessed effect modification and indirect pathways. Results: The prevalence of occupational stress was 28.8%. Workers with occupational stress had higher odds of depressive symptoms (OR = 4.33, 95% CI: 3.017–6.216), insomnia (OR = 1.91, 95% CI: 1.444–2.524), and WMSDs (OR = 2.071, 95% CI: 1.490–2.879). Younger workers (16–30 years) and those with lower incomes (< 3,000 CNY/month) were at greater risk. Insomnia partially mediated the associations between occupational stress and depressive symptoms (16.0%) and WMSDs (7.7%). A dose-response relationship was observed. Conclusion: Occupational stress is a significant risk factor for mental and physical health issues among metal mining workers, with younger and low-income workers being particularly vulnerable. Insomnia partially mediates these associations, underscoring the need for targeted workplace interventions to mitigate stress-related health consequences and improve worker well-being.