Impacts of triclosan exposure on zebrafish early-life stage: Toxicity and acclimation mechanisms

Proteomic and enzymatic analyses were conducted on 7 days post fertilization (dpf) larvae exposed to 50 μg/L and 100 μg/L of TCS giving insights into the functional changes triggered at those specific concentrations. TCS seemed to affect proteins involved in cytoskeleton, stress response, eyes and neuronal development. This was endorsed by the enzymatic results, which suggest impairment in glutathione metabolism and acute neurotoxicity. A significant 2.5-fold and 3-fold increase of AChE activity was observed following TCS exposure. Moreover, GPx activity was significantly increased whereas a significant inhibition of GR activity was observed, suggesting that de novo synthesis of reduced GSH might occur in order to maintain the ratio between reduced and oxidized GSH. Proteomic results revealed possible candidate protein involved in the acclimation process of larvae exposed to 100 μg/L of TCS. Our integrative analysis revealed complex non-monotonic concentration-related effects on zebrafish early-life stages with increased resistance between 50 and 100 μg/L exposures. This research highlighted oxidative stress and neurotoxicity as major toxicity mechanisms of TCS during development.