Myeloperoxidase-mediated bioactivation of 5-hydroxythiabendazole: A possible mechanism of thiabendazole toxicity

► Myeloperoxidase is able to convert 5OH-TBZ to a cytotoxic, reactive, intermediate. ► The reactive intermediate was equally toxic to various cell types: NRK-52E, H9C2, and rat primary proximal tubule cells. ► The reactive intermediate induces cell death through necrosis rather than apoptosis. ► The bioactivation of 5OH-TBZ can be prevented by the MPO inhibitor rutin. ► The reactive intermediate is the only significantly toxic thiabendazole product in vitro, and may cause toxicities in vivo.