Potassium bromate as a probable human Carcinogen: multi-organ toxicity and chemopreventive potential of dietary antioxidants-a comprehensive review

Abstract Potassium bromate (KBrO₃), classified as a probable human carcinogen, has long been used as a flour-improving and oxidizing agent in baking and food processing industries. It is also generated as a by-product during ozonation of drinking water, raising concerns about widespread, low-dose exposure. Experimental studies consistently demonstrate that KBrO₃ induces multiple-organ toxicity primarily through oxidative stress-mediated mechanisms. Exposure to KBrO₃ leads to excessive generation of reactive oxygen species, resulting in depletion of glutathione reserves, enhanced lipid peroxidation, and oxidative DNA damage. Such genotoxic effects include DNA strand breaks, micronuclei formation, and chromosomal aberrations, which collectively contribute to its well-documented carcinogenic and mutagenic potential. Consequently, these molecular alterations promote renal, hepatic, and thyroid tumor formation reported in experimental animal models, while emerging epidemiological evidence suggests possible associations between chronic dietary exposure to KBrO₃ and gastrointestinal malignancies in humans. However, recent research has thoroughly investigated the chemopreventive potential of dietary antioxidants in mitigating KBrO₃-induced toxicity, highlighting their ability to attenuate oxidative damage through enhancement of endogenous antioxidant defenses, modulation of the key cytoprotective signaling pathways and restoration of cellular redox homeostasis. With continued usage of KBrO₃ and the inconsistency of regulatory enforcement worldwide, strengthening risk assessment, surveillance and preventive strategies-particularly the substitution of KBrO₃ with safer alternatives and the promotion of antioxidant-rich diets is crucial to reduce long term carcinogenic risk and safeguard global public health.