Objective
The aim of the study was to assess cognitive functions, depression, anxiety, and personality changes in workers in the aluminium industry.
Participants and methods
A cross-sectional analytical study was carried out on 50 workers employed in ‘General Metal Company’, which manufactures aluminium. Fifty individuals with no history of occupational exposure to aluminium were randomly selected from relatives of patients attending the outpatient clinic of industrial medicine in Kasr Al Aini hospital to form a control group. Both groups were matched for age and sex. All of the examined individuals were subjected to clinical, laboratory and environmental examinations that included aluminium and copper dust measurement, noise measurement and heat measurement. The workers were diagnosed according to the ICD-10 research diagnostic criteria. Both groups were subjected to different neuropsychological tests that included the Mini Mental State Examination (MMSE), the Hamilton Depression Rating Scale (HDRS), the Hamilton Anxiety Rating Scale (HARS), the Eysenck Personality Questionnaire (EPQ) and the Wechsler Memory Scale (WMS).
Results
The results showed that serum and urinary aluminium levels were higher in the exposed group when compared with the control group (nonexposed group), with highly statistically significant differences. However, there was no statistically significant difference between the groups with respect to serum copper. There were statistically significant differences between them in all subtests of the WMS (information, orientation, logical memory, digit span and associate learning) except with respect to mental control. Most cases were within the normal range of values according to MMSE, but there was a statistically significant difference. There was a statistically significant difference between the exposed and control individuals as regards all subscales of the EPQ (psychotism, neurotism, extroversion, lying and criminality). Seven per cent of workers had severe depression, 11% had moderate depression and 25% had mild depression in the exposed group, whereas 20% had mild depression in the control group. There was a statistically significant difference between the exposed and control group with respect to depression. Six per cent of workers in the exposed group had severe anxiety, whereas 30 and 34% had mild and moderate anxiety levels, respectively. There was a highly statistically significant difference between the exposed and control groups with respect to anxiety. There was statistically significant negative correlations between serum and urinary aluminium level and the information, logical memory and digit span subtests of the WMS. Serum copper shows no significant correlations with all subtests of Wechsler Memory Scale (WMS). The increase in serum and urinary aluminium levels led to a decrease in the scores of MMSE (a negative correlation, which was statistically significant). In contrast, serum copper showed no statistically significant correlation with the scores on MMSE. There was no statistically significant correlation between metal levels in the exposed group (serum aluminium, urinary aluminium and serum copper) and any of the parameters of the Eysnek personality test, apart from criminality, which seemed to have a statistically significant positive correlation with serum aluminium level. There was a statistically significant positive correlation between serum aluminium and HDRS, whereas there was no statistically significant correlation between urinary aluminium and serum copper with HARS. There was a statistically significant positive correlation between serum aluminium and the HARS. With respect to urinary aluminium and serum copper, there was no statistically significant correlation with the HARS.
Conclusion
The study showed that exposed workers in the aluminium industry are suffering from cognitive decline, memory affection, depression, anxiety and personality changes. Proper monitoring and improved hazard control are strongly recommended.