Objective To explore the changes of cognitive function in male smelting workers with exposure to various levels of manganese (Mn) and its possible influencing factors.
Methods A total of 240 male smelting workers were chosen from a Mn smelter in Guangxi and divided into high (86 workers) and low (154 workers) Mn exposure groups according to a cumulative exposure index (CEI);240 male workers of a sugar refinery in the same region were selected as the control group. All participants were required to complete questionnaires to collect general information and evaluate cognitive function by the Montreal Cognitive Assessment (MoCA) test (Beijing version).
Results There was a negative association between cognitive function and the Mn cumulative exposure levels in male smelting workers (r=-0.324, P<0.05). The MoCA scores of the 2 exposure groups were remarkably lower than that of the control group (P<0.01), and the group with high Mn exposure level reported significantly lower scores than the group with low Mn exposure level (P<0.05), after adjusted age, marital status, and other related variables. The results of multiple linear regression analysis showed that the worker's cognitive function was significantly affected by age, education, Mn exposure level, and smoking (P<0.05).
Conclusion Occupational Mn exposure might decrease the cognitive function in male smelting workers. Moreover, the cognitive function could also be affected by age, education, and smoking.
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