Neuropsychologic "impairment" in a cohort of hospital workers chronically exposed to ethylene oxide

Abstract Ethylene Oxide is widely used to sterilize heat-sensitive materials. Acute and chronic neurogenic effects to the central and peripheral nervous system in man and animals have been described. To assess the chronic, subtle neuropsychologic effects of ethylene oxide, we performed a cross-sectional study of 25 hospital central supply workers exposed to low levels of ethylene oxide and 24 unexposed control workers. Subjects were tested using a neuropsychological screening battery by examiners blinded to exposure status. Testing results were reviewed independently by two neuropsychologists without knowledge of exposure. Subject status was categorized as normal, "impaired," or disagreement (between the two neuropsychologists). There were significantly more subjects concordantly judged as impaired in the exposed group versus the control group (X2 2 = 6.0861, p < 0.05). Although limited by the cross-sectional study design and the global categorization, these findings suggest that CNS dysfunction and cognitive impairment may result from chronic ethylene oxide exposure in hospital central supply units.