Determining Associations Between Levels of Ethylene Oxide Gas Exposure and Neurocognitive Performance for Older U.S. Adults

Ethylene oxide (EtO) gas is a widely used industrial chemical and known health hazard. Multiple studies have determined that EtO exposure can be measured via hemoglobin adduct levels, and EtO exposure increases the risk of cancer and neurocognitive deficits, especially with occupational exposure. Emerging studies indicate that neighboring communities are also at risk. The purpose of this study is to explore the relationship of known covariates and EtO hemoglobin adduct levels to neurocognitive performance in older U.S. adults. This exploratory study drew its sample from the publicly available NHANES dataset. The 2013-2014 NHANES measured EtO exposure via hemoglobin adducts and the cognitive domain of neurocognitive function using the CERAD, Animal Fluency, and Digit Symbol Substitution (DSST) tests. Motor function was measured using grip strength. Participants were grouped into background (≤27.36 pmol/gHb) or elevated (>27.36 pmol/gHb) EtO exposure. Hierarchical linear regression, independent <i>t</i>-tests, and logistic regression analyses were performed. A total of 10,175 individuals were sampled: 489 were included in the cognitive analyses, and 436 were included in the motor analyss. Elevated EtO adduct levels significantly predicted low Animal Fluency, DSST, CERAD, and combined grip strength scores. Our findings are supported by the extant literature citing neurotoxic EtO exposure effects. Further study in known EtO-exposed communities is warranted.