Effects of fluoride on psychomotor performance and memory of aluminum potroom workers

Abstract

In this cross-sectional study, the psychomotor performance and memory skills of a fluoride-exposed group (FEG) of 64 male workers in an aluminum potroom were compared with those of 60 male workers in a nonfluoride-exposed group (NFEG). The FEG had a mean age of 37.59±4.82 yr and had been employed for 13.06±4.29 yr, which compared closely with the NFEG. Both groups were selected randomly and had no previous history of neuropsychological, hepatic, renal, or immune disorders. The neurobehavioural functions were measured using the World Health Organization neurobehavioural core test battery (NCTB), a computer based test, for reaction time, and a Purdue pegboard test for manual dexterity and hand-eye coordination. The FEG had significant impairments compared to the NFEG for mean reaction time, Purdue pegboard for the preferred hand and both hands, pursuit aiming, digit span, Benton Visual Retention (p<0.001), and digit symbol memory (p<0.01). The digit symbol performance scores, but not those for the other parameters, decreased with increased work duration (p<0.05). Overall, the mechanism for the impairments did not appear to be the result of impaired thyroid function. We conclude that neurobehavioural testing is useful for detecting impairment of psychomotor performance and memory that associated with occupational F exposure.