Environmental factors affecting thyroid function of wild sea bass (Dicentrarchus labrax) from European coasts

► Contaminant concentrations affect the thyroid in sea bass from the major European coastal regions. ► The hepatic T4 outer ring deiodinase and T4 sulfation are affected T4 glucuronidation was not affected. ► The observations can be interpreted as a pathway to homeostatically maintain thyroid hormone status. ► The higher chlorinated PCBs seemed to be the most implicated in this perturbation.