Acrylamide neuropathy in a South African factory: an epidemiologic investigation

Acrylamide monomer concentrations and peripheral neurotoxicity were investigated in workers at a factory producing polymer. Monomer levels ranged from 0.07 to 2.5 times the recommended exposure limit of the U.S. National Institute for Occupational Safety and Health (1988). Those workers with exposure exceeding the limit had increased prevalences of acrylamide-related abnormalities. Logistic regression showed dose-response relationships with exposure for symptoms, abnormal sensation, decreased motor strength, abnormal gait or rombergism, and skin abnormalities. The overall prevalence of acrylamide-related abnormality was 32% in the total work force and 67% among those exceeding the limit compared with 14% in those exposed below the limit. Environmental exposure determinations and conventional clinical approaches are relatively insensitive measures. Associations might have been stronger if a biological exposure measure had existed and if quantitative neurometric techniques had been applied. Electrophysiological methods are not readily available in many settings; the use of the Vibration II for quantitative field testing holds promise.