Serum Concentrations of Benzaldehyde, Isopentanaldehyde and Sex Hormones: Evidence from the National Health and Nutrition Examination Survey

Exposure to environmental chemicals could disturb the balance of sex hormones. However, the studies on Benzaldehyde, Isopentanaldehyde exposure and sex hormones are still limited. Based on the data of 1064 participants in the National Health and Nutrition Examination Survey (NHANES), we used the linear regression model and restricted cubic spline (RCS) model to evaluate the associations of Benzaldehyde/Isopentanaldehyde exposure with testosterone (TT), estradiol (E2), sex hormone binding globulin (SHBG), free androgen index (FAI) and the ratio of TT to E2 (TT/E2). A ln-unit increase in Benzaldehyde was associated with lower TT (β = −0.048, P = 0.030) and E2 (β = −0.094, P = 0.046) in all participants. After further adjustment for menopausal status, Benzaldehyde was negatively associated with E2 (β = −0.174, P = 0.045) in females. The interaction between Benzaldehyde and gender was significant (P(inter) = 0.031). However, Isopentanaldehyde showed a positive association with SHBG and TT/E2 in all participants (all P < 0.05). The positive associations of Isopentanaldehyde with TT, SHBG and TT/E2 were found in males but not in females. RCS plots illustrated the linear associations of Benzaldehyde with E2 (P(non-linear) = 0.05) in females and Isopentanaldehyde with TT (P(non-linear) = 0.07) and TT/E2 (P(non-linear) = 0.350) in males. The non-linear relationships were identified between Isopentanaldehyde and SHBG in males (P(non-linear) = 0.035). Our findings indicated the effects of Benzaldehyde and Isopentanaldehyde exposure on sex hormones, and the effects had the gender specificity. Cohort studies and high-quality in vitro and in vivo experiments are needed to confirm the specific effects and uncover the underlying mechanisms.