BIOELECTRICAL ACTIVITY OF THE CENTRAL-NERVOUS-SYSTEM AMONG POPULATIONS IN A RARE-EARTH ELEMENT AREA

Auditory brainstem electric response (ABR) and somatosensory evoked po tential (SEP) of 21 subjects (41 ears) among villagers in a rare earth element (REE) area in Can County, Jiangxi, China, were studied. No di fference in ABR between the subjects from the REE area and the control group was noted. However, the conduction detected by SEP from the med ian nerve to the thalamus (P-15) was shortened (P < 0.05), especially to the first-grade primary somatosensory responsive region (S-1) (P < 0.01) and the amplitude of S-1 decreased (P < 0.05), indicating that R EE was difficult to accumulate in the brainstem, but it was susceptibl e to cerebral cortex, thus causing subclinical damage. This condition was confirmed in the animal experiment. It was suggested that the toxi city through long-term intake of small doses of REE might not be negli gible, and the hazard of REE environments should be investigated.