This study investigates the association between blood ethylene oxide (HbEO) levels and the risk of metabolic syndrome (MetS) using data from the National Health and Nutrition Examination Survey (NHANES) 2013-2020. The study found a positive correlation between HbEO levels and the risk of MetS, with higher HbEO levels associated with increased MetS risk. The association was dose-responsive, suggesting a linear relationship between HbEO levels and MetS risk. Subgroup analyses revealed that the relationship varied by gender, age, and BMI, with a non-linear, L-shaped association in females, non-obese individuals, and those aged 50 and older. The study also found that HbEO levels were positively associated with components of MetS, including elevated waist circumference, reduced high-density lipoprotein cholesterol, and elevated triglycerides. However, HbEO levels were negatively associated with the risk of diabetes. The study highlights the potential role of HbEO as a risk factor for MetS and its components, suggesting that exposure to ethylene oxide may contribute to the development of MetS through inflammatory and metabolic pathways. The findings underscore the importance of further research to elucidate the mechanisms underlying the association between HbEO exposure and MetS, as well as to explore potential interventions to mitigate the risk of MetS in populations exposed to ethylene oxide. The study contributes to the understanding of the pathogenesis of MetS and provides new insights into the role of environmental factors in the development of this complex condition.This study investigates the association between blood ethylene oxide (HbEO) levels and the risk of metabolic syndrome (MetS) using data from the National Health and Nutrition Examination Survey (NHANES) 2013-2020. The study found a positive correlation between HbEO levels and the risk of MetS, with higher HbEO levels associated with increased MetS risk. The association was dose-responsive, suggesting a linear relationship between HbEO levels and MetS risk. Subgroup analyses revealed that the relationship varied by gender, age, and BMI, with a non-linear, L-shaped association in females, non-obese individuals, and those aged 50 and older. The study also found that HbEO levels were positively associated with components of MetS, including elevated waist circumference, reduced high-density lipoprotein cholesterol, and elevated triglycerides. However, HbEO levels were negatively associated with the risk of diabetes. The study highlights the potential role of HbEO as a risk factor for MetS and its components, suggesting that exposure to ethylene oxide may contribute to the development of MetS through inflammatory and metabolic pathways. The findings underscore the importance of further research to elucidate the mechanisms underlying the association between HbEO exposure and MetS, as well as to explore potential interventions to mitigate the risk of MetS in populations exposed to ethylene oxide. The study contributes to the understanding of the pathogenesis of MetS and provides new insights into the role of environmental factors in the development of this complex condition.