Avermectin induces photoreceptor functional impairment and color vision deficits in zebrafish (Danio rerio).

The effects of avermectin on the visual function of nontarget organisms, particularly aquatic organisms, require further evaluation. Avermectin can come into direct contact with the eyes of nontarget organisms through air or water. However, few studies have investigated the safety of avermectin in the eyes of nontarget organisms. Therefore, it is important to assess its safety in the eyes of nontarget organisms. The results demonstrate that avermectin induces ocular morphological abnormalities, retinal structural damage, and decreased locomotor behavior in zebrafish larvae. Further analyses indicate that avermectin-induced ocular toxicity in zebrafish larvae is associated with the thyroid hormone and retinoic acid signaling pathways. The evaluation of the effect of avermectin on the visual function of adult zebrafish reveals that avermectin induces changes in the sensitivity of adult zebrafish to different light wavelengths and colors. Male adult zebrafish showed greater variation, suggesting possible sex differences. These results indicate that avermectin induces ocular developmental damage in zebrafish larvae and visual behavioral abnormalities in adult zebrafish.