Neuropsychological deficit among elderly workers in aluminum production

Abstract

A cross-sectional study was conducted at a Norwegian primary aluminum plant. All workers aged 61-66 years were offered early retirement benefits. Among the workers, 47 met the study criteria and 38 (81%), comprising 14 potroom workers, 8 foundry workers, and 16 controls, volunteered to participate. They were tested with a neuropsychological test battery. Workers in potrooms with Søderberg electrolytic cells were found to show signs of impairment of the nervous system. A test for tremor discriminated significantly between the potroom group and the controls. There was a suggestion of increased risk of impaired visuospatial organization and a tendency to a decline in psychomotor tempo in the potroom workers. We suggest that the above findings may be related to long-term occupational exposure in the potroom, and further to chronic low-dose exposure to aluminum.

Body burden of aluminum in relation to central nervous system function among metal inert-gas welders

“…The present study was able to reproduce the results of the memory tests only for visual memory, but indeed confirmed the effect on attention. Impaired motor function was suggested for potroom workers in a primary aluminum plant (27) and also among aluminum welders (48). In our study, no effects on psychomotor functions were noted, but it must be kept in mind that few tests were used to explore this domain.…”

“…Qualitatively, previous studies involving foundry work and primary aluminum production (17,26,27) have suggested that a long-term, low-level exposure to aluminum does not deteriorate the general cognitive level estimated by measurements of intelligence quotient, but it may affect performance in tests that are known to be sensitive to diverse disturbances in brain function, including neurotoxic damage (eg, digit symbol and block design). The results of previous studies (17, 26, 3 1) have also indicated the vulnerability of memory and attention.…”

“…In another case, a 78-year-old former flake powder worker who had a previous diagnosis of aluminosis was found to be moderately demented with motor disturbances, and he exhibited a high aluminum concentration in his CSF (25). There are reports of impaired cognitive or psychomotor functions, emotional instability, and depression among aluminum foundry workers (17), primary aluminum production (potroom) workers (26,27), and miners exposed to particulate aluminum, purported to be a prophylactic against silicosis (28). Aluminum workers were not overrepresented among the nearly 200 patients of Alzheimer's disease in a case-referent study (29).…”

Effects of Aluminium Chloride Exposure on the Histology of the Cerebral Cortex of Adult Wistar Rats

“…Studies on workers exposed to Al dust in industrial environments demonstrate similar effects (Rifat, et al, 1990;Bast-pettersen, et al, 1994;White et al, 1992, Akila et al, 1999. Many researchers have found elevated Al levels to be associated with a decline in visual memory, attention, concentration, frontal lobe function and lower vocabulary scores in hemodialysis patients (Bolla et al, 1992).…”

Neurocognitive Effects in Welders Exposed to Aluminium: An Application of the NPC Test and NPC Ranking Methods

“…Hänninen et al (1994) described a decrease in the neuropsychic response, with short-term memory and attention disturbances, and effects on cerebral electric activity at the front of the brain correlated to the Al-s in the 17 shipyard welders with exposure characteristics similar to those in our sample. Bast-Pettersen et al (1994) showed "a suggestion of increased risk of impaired visuospatial organization and tendency to a decline in psychomotor tempo in the potroom workers''. Sjögren et al (1996), with reference to welders exposed to aluminium and manganese, concluded that the observed neurotoxic effects were due to combined exposure to the two metals.…”