HUMAN-PERFORMANCE DURING EXPOSURE TO TOLUENE

Purpose: The purpose of this research was to examine the effects of in halation of toluene on respiratory function and neuropsychological per formance of humans. Methods: We exposed six healthy adults to 100 ppm toluene or air (control) for 6 h, in a double-blind, randomized fashio n, with exposures separated by at least 14 d and including 30 min of e xercise at a level that quadrupled minute ventilation. Blood and exhal ed air toluene levels were measured before, during, immediately, and 1 and 2 h post-exposure. Lung function was measured before and immediat ely after exposure. Three repetitions of two computerized neuropsychol ogical tests were performed, including a brief standard neuropsycholog ical battery (ANAM) and a l-h complex performance test (SYNWORK). Stat istical analysis of the psychological data was conducted as a repeated measures ANOVA. Findings: Following exercise, the mean blood and exha led air toluene levels averaged 1.5 mu g and 28 ppm, respectively. Lun g function was unchanged post-exposure. On the SYNWORK test, the Compo site score obtained over time during toluene exposure was lower than t hat during room air (F = 29.20, p = 0.005), with the score from the fi nal hour reduced by 10%. On standard neuropsychological tests, latency but not accuracy proved the sensitive measure for five of the seven s ubtests presented. Conclusions Performance of complex tests and respon se time to simple brief tests can be disrupted by toluene inhalation a t 100 ppm. Differences in performance between air and toluene conditio ns were greatest after exercise, indicating that physical activity may enhance the response to volatile organic solvents.