Cognitive Effects of Aluminum Exposure in Cement Factory Workers: A Mini-Mental State Examination (MMSE) Assessment
Main Article Content
Keywords
Occupational aluminium exposure, Cognitive function, MMSE, Biomarker
Abstract
Background: Aluminum (Al) is a widely encountered heavy metal with known neurotoxic effects. Occupational exposure, particularly in industrial settings, may impair cognitive functions. This study aimed to evaluate the relationship between Al exposure and cognitive function. Methods: A retrospective study was conducted at Gazi University Faculty of Medicine Hospital, Occupational Diseases Outpatient Clinic, between December 5, 2024, and January 5, 2025. The exposed group consisted of 20 male cement factory workers with elevated urinary Al expressed as a function of creatinine, and the control group included 40 age-matched males without occupational Al exposure (1:2 matching). Cognitive status was assessed using the Mini Mental State Examination (MMSE). Urinary Al levels were measured by inductively coupled plasma mass spectrometry (ICP-MS). Statistical analyses were performed with SPSS 29.0. Results: The mean MMSE score was significantly lower in the exposed group compared with controls (24.3±3.7 vs. 28.5±2.3, p<0.001). Subscale scores for orientation, attention/calculation, recall, and language were also lower in exposed workers. All such workers had elevated aluminum (mean 42.3±21.4 mcg/g creatinine). Urinary Al was positively correlated with working duration (r=0.453, p=0.045) and negatively correlated with MMSE (r=-0.486, p=0.030) and orientation scores (r=-0.494, p=0.027). Conclusion: Workers occupationally exposed to aluminum exhibited significantly lower cognitive performance than non-exposed controls. Higher urinary Al levels were associated with poorer cognitive outcomes, suggesting neurotoxic effects of aluminum and underscoring the importance of preventive strategies and cognitive monitoring in exposed populations.
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