Finger tremor after carbon disulfide-based pesticide exposures
L. J. Chapman, S. L. Sauter, R. A. Henning, R. L. Levine, C. G. Matthews and H. A. Peters
Department of Neurology, University of Wisconsin Medical School, Madison.
Index finger tremor accompanying voluntary movement was studied in 19
age-matched control subjects and in 19 grain industry employees chronically
exposed to carbon disulfide-based fumigants. Visual judgments of tremor
amplitude made by neurologists during clinical examinations equaled the
sensitivity of computerized tremor amplitude measurements. Tremor frequency
variations detectable only with computerized measurement were present in
grain workers with and without increased tremor amplitudes. Frequency
differences discriminated between normal subjects and 74% of the grain
workers. The distribution of tremor frequency power in the grain workers
was often sequestered at 5 to 7 Hz, reminiscent of tremor in idiopathic
Parkinson's disease. These findings suggest that the measurement of subtle
tremor frequency changes may provide an early indication of chronic carbon
disulfide poisoning.
