NEUROBEHAVIORAL EVALUATION OF VENEZUELAN WORKERS EXPOSED TO ORGANIC-SOLVENT MIXTURES

To assess the applicability of the World Health Organization (WHO) Neu robehavioral Core Test Battery (NCTB), we evaluated 53 male and 29 fem ale Venezuelan workers exposed to mixtures of organic solvents in an a dhesive factory, and 56 male and 11 female workers unexposed to any ty pe of neurotoxic chemical. The average age of unexposed workers was 30 years and 33 years for those exposed, average schooling for both grou ps was 8 years, and the mean duration of exposure was 7 years. The NCT B, which assesses central nervous system functions, is composed of sev en tests that measure simple motor function, short-term memory, eye-ha nd coordination, affective behavior, and psychomotor perception and sp eed. The battery includes: profile of mood states (POMS); Simple React ion Time for attention and response speed; Digit Span far auditory mem ory; Santa Ana manual dexterity; Digit-Symbol for perceptual motor spe ed; the Benton visual retention for visual perception and memory; and Pursuit Aiming II for motor steadiness. In each of 13 subtests, the ex posed group had a poorer performance than the nonexposed group. The ra nge of differences in mean performance was between 5% and 89%, particu larly in POMS (tension-anxiety, anger-hostility, depression-rejection, fatigue-inertia, confusion-bewilderment), Simple Reaction Time, Digit -Symbol, and Santa Ana Pegboard (p < .05). In multivariate regression analyses, controlling for the effects of age, sex, and education, sign ificantly poorer performance in the exposed was found for tension-anxi ety, hostility, depression, and confusion moods in the POMS, and in di git-symbol and simple reaction time (p < .05). These alterations were also dose-related using years of exposure in analyses of covariance. C ompared to the nonexposed, the exposed subjects demonstrated an increa sed frequency of subjective symptoms of fatigue, difficulties with mem ory, confusion, paresthesias in upper and lower extremities, and sleep disturbances. We conclude that the methodology is applicable to the p opulation studied. The tests of the NCTB were accepted by the subjects and were administered satisfactorily, except for occasional difficult ies in verbal comprehension in subtests of POMS, which is the only tes t that requires more demanding verbal skills. The magnitude of the beh avioral deficits is consistent with the probable high level of exposur e and with the range of deficits previously reported in workers with l ong-term solvent exposures. (C) 1995 Wiley-Liss, Inc.