Effects of diesel exhaust on neurobehavioral and pulmonary functions

Ten railroad workers and 6 electricians referred for shortness of breath al so had slowness of response, memory loss, and disordered sleep, all of whic h suggested neurobehavioral impairment. The hypothesis was that diesel exha ust causes central nervous system impairment. Six electricians worked withi n enclosed concrete walls and roofs that trapped diesel exhaust from trucks . Seven railroad mechanics had tuned diesel engines indoors for 15-50 y, an d 3 crewmen rode in locomotives. Neurobehavioral and visual functions were measured with a 26-test battery. Compared with unexposed men, the 16 in thi s study had significantly impaired reaction time, balance, blink reflex lat ency R-1, Culture Fair, peg placement, trail making, and verbal recall. Thi rteen men had abnormal visual fields, and 11 had abnormal color confusion i ndices. Nine men had airways obstruction. The author could not attribute ab normalities to confounding factors or bias. Severe neurobehavioral impairme nt was associated with exposure to confined diesel exhaust. In additional s tudies of diesel-exposed workers, especially drivers of locomotives and tru cks, investigators should use sensitive neurobehavioral methods.