Investigating the Mediating Effects of Urinary Phenols and Parabens on the Relationship Between Phthalate Exposure and Metabolic Changes in Adults

Background Phthalates and other environmental contaminants, such as phenols and parabens, have been implicated in metabolic health disturbances. This study investigates the mediating effects of urinary phenols and parabens on the relationship between phthalate exposure and Metabolic Changes in adults. Methods: Data from the National Health and Nutrition Examination Survey (NHANES) 2009–2010 cycle were utilized, encompassing 1,669 adults. Phthalate exposure was measured via urinary Ethyl Paraben. BMI served as a proxy for metabolic health changes. The analysis employed mediation models to explore whether urinary phenols and parabens mediate the relationship between phthalate exposure and metabolic Changes, adjusting for covariates. Results: The median age of participants was 46 years, with nearly equal gender distribution (51% males and 49% females). The mediation analysis revealed significant mediation effects for Benzophenone-3 and Propyl Paraben. For Benzophenone-3, the Average Causal Mediation Effect (ACME) was − 0.000773 (95% CI: -0.001242 to 0.000, p < 2e-16), and the direct effect (ADE) was − 0.004198 (95% CI: -0.008295 to 0.000, p = 0.016). Similarly, Propyl Paraben presented significant mediation with an ACME of -0.00105 (95% CI: -0.00159 to 0.000, p = 0.020), and the direct effect (ADE) was − 0.00393 (95% CI: -0.00789 to 0.000, p = 0.036). Conclusion: This study provides robust evidence that specific urinary phenols and parabens significantly mediate the relationship between phthalate exposure and metabolic Changes, shedding light on the pathways through which environmental contaminants might influence metabolic health. The findings underscore the necessity for further research and regulatory measures to mitigate exposure to these chemicals and their impacts on metabolic health.