Transgenerational toxicity of Tralopyril: Ferroptosis mediates reproductive and skeletal disruption in Oryzias melastigma

Tralopyril is a known endocrine-disrupting chemical that interferes with the thyroid hormone system. Using Oryzias melastigma , we established a full life-cycle exposure and multigenerational model (F0-F3) to investigate the reproductive and skeletal toxicity of tralopyril. Results showed disrupted gonadal maturation, abnormal sex hormone levels, and altered expression of HPG axis genes, with sex-specific feedback patterns. Collagen accumulation and activation of cathepsin K indicated transgenerational bone matrix imbalance. In F1-F2 larvae, downregulation of bmp4 and col2a1a was associated with craniofacial skeletal deformities and delayed mineralization. Fluctuations in thyroid hormone levels and upregulation of tshβ were linked to bone toxicity, whereas increased erβ expression suggested estrogen-mediated skeletal effects. Parental hormone profiles showed strong correlations with offspring bone phenotypes, indicating multigenerational endocrine disruption. Additionally, abnormal tissue iron and glutathione levels, together with increased fth1 expression, suggested that ferroptosis contributed to multigenerational toxicity. These findings highlight tralopyril's persistent ecological risks, emphasizing the need for regulatory focus on emerging pollutants. • Tralopyril induced multigenerational reproductive and skeletal toxicity in Oryzias melastigma . • Persistent endocrine disruption and bone matrix imbalance were observed across F0–F3 generations. • Ferroptosis is involved in the transgenerational toxicity of tralopyril. • Sex-specific and tissue-dependent responses revealed complex regulatory effects. • Cross-generational hormone status significantly influenced bone development and gene expression in offspring.