No abstract

Results of neurobehavioral testing in 305 histology technicians were studied by regression analysis with age, years of cigarette smoking, and hours per day of exposure to formaldehyde and to solvents as major independent variables. Increasing age was associated with poorer performance on visual memory, block design, trails, dexterity by pegboard, sharpened-Romberg, finger writing, as well as with longer choice reaction time. Increased daily hours of exposure to formaldehyde were correlated with reduced performance on story memory, visual memory, digit span, pegboard and sharpened-Romberg, as well as with errors on trails. Exposure to solvents was associated only with diminished recall of story.

Hydrogen sulfide (H2S) above 50 parts per million (ppm) causes unconsciousness and death. Lower doses of H2S and related gases have been regarded as innocuous, but the effects of prolonged exposure have not been studied. This study was designed to determine whether people exposed to sulfide gases as a result of working at or living downwind from the processing of "sour" crude oil demonstrate persistent neurobehavioral dysfunction. Thirteen former workers and 22 neighbors of a refinery complained of headaches, nausea, vomiting, depression, personality changes, nosebleeds, and breathing difficulties. Their neurobehavioral functions and a profile of mood states (POMS) were compared to 32 controls, matched for age and educational level. The exposed subjects' mean values were statistically significantly abnormal compared to controls for two-choice reaction time, balance (as speed of sway), color discrimination, digit symbol, trail-making A and B, and immediate recall of a story. Their POMS scores were much higher than those of controls. Visual recall was significantly impaired in neighbors, but not in exworkers. It was concluded that neurophysiological abnormalities were associated with exposure to reduced sulfur gases, including H2S from crude oil desulfurization.

Background: This is a community comparison study that examines persons living in a subdivision exposed to petroleum products and mercury.

Disturbances of memory, mood, equilibrium, and sleep that occurred simultaneously with headache and indigestion, were experienced more frequently among women working in histology who had daily exposure to formaldehyde, xylene, and toluene than in unexposed female clerical workers working in the same hospitals. Neurobehavioral symptoms were accompanied by irritation of eyes, upper airways, and trachea. Formaldehyde exposure correlated better with neurobehavioral symptoms and with respiratory and mucous membrane symptoms than did exposure to xylene/toluene or to other agents.