이장재 (한국화학연구원)

조성희 (한국화학연구원)

이장재 (한국화학연구원)

박창범 (안전성평가연구소)

김준곤 (고려대학교)

조성희 (한국화학연구원)

Endocrine-disrupting chemicals (EDCs) are known to interfere with hormonal systems, leading to significant health issues. This study investigates the sex-specific crosstalk between thyroid hormones (THs) and sex steroid hormones (SSHs) upon exposure to EDCs, specifically focusing on the impacts of tris(1,3-dichloro-2-propyl) phosphate (TDCPP) and 4-tert-octylphenol (OP), and their impact on reproductive dysfunction. Zebrafish were exposed to these chemicals for 21 days, and hormone levels were quantified using LC-MS/MS. Biological indicators such as vitellogenin (VTG) mRNA, estrogen receptors (ER), and androgen receptors (AR) were also measured.

Results showed significant sex-specific hormonal responses to EDC exposure. In female zebrafish, exposure to TDCPP and OP led to changes in thyroid hormones (T3, T4) and sex steroid hormones (E2, Prog), along with alterations in VTG mRNA expression. These hormonal disruptions resulted in impaired oocyte development and decreased reproductive success. In male zebrafish, exposure to these chemicals led to changes in testosterone (T) and 11-ketotestosterone (11-KT) levels, combined with increased aromatase activity leading to altered estradiol levels, which were associated with reduced spermatogenesis and compromised reproductive performance. The strong correlation between altered THs and disrupted SSH biosynthesis underscores the crosstalk between these hormones.

This study provides evidence of sex-specific hormonal crosstalk induced by TDCPP and OP, leading to reproductive dysfunction. These findings underscore the importance of considering sex-specific responses in the risk assessment of endocrine disruptors and highlight the need for further research on the underlying mechanisms of this hormonal interaction.