Endocrine disruption in thicklip grey mullet (Chelon labrosus) from the Urdaibai Biosphere Reserve (Bay of Biscay, Southwestern Europe)

► High prevalence of intersex gonads was found in the Urdaibai Biosphere Reserve. ► High levels of alkylphenols were measured in fish bile. ► VTG protein was detected in the plasma of undifferentiated, male and intersex fish. ► Levels of phthalate and organotins measured in sediments are of great concern. ► This study provided evidence of EDs presence in the Urdaibai Biosphere Reserve.