Early-Life Exposure to the Cooking Oil Fume Component trans,trans-2,4-Decadienal Impairs Ocular Development and Angiogenesis in Zebrafish (Danio rerio) Larvae

Trans,trans-2,4-decadienal (tt-DDE), the primary aldehyde component found in cooking oil fumes, is a prevalent environmental pollutant. However, its potential adverse effects on ocular development remain largely unexplored. This study evaluated its toxicity on ocular development and angiogenesis in zebrafish larvae, as well as on human retinal vascular endothelial cells (HRECs). Zebrafish (Danio rerio) larvae at 48 h post-fertilization were microinjected intraocularly with various doses of tt-DDE (65.87–521.3 mM) for 24 h. We observed dose-dependent impairments in ocular development following tt-DDE exposure. It significantly reduced eye size and inhibited the intraocular vascular area at concentrations of 128.9 mM and above. Histopathological analysis revealed retinal structural disorganization, eye shrinkage, and a clear dose-dependent increase in acridine orange (AO) fluorescence intensity. Apoptosis assays confirmed a significant escalation in ocular cell death at higher exposure doses. Additionally, our results demonstrated that tt-DDE (5–100 μM) significantly reduced the viability of HRECs in vitro. These findings suggest that early-life exposure to tt-DDE impairs ocular development in zebrafish by inducing histopathological damage, inhibiting angiogenesis, and promoting apoptosis, and also exerts direct cytotoxicity to human retinal cells. This study underscores the potential risk of tt-DDE exposure as an environmental factor contributing to ocular developmental toxicity.