Endocrine disrupting effects of bisphenol A exposure and recent advances on its removal by water treatment systems. A review

Bisphenols (BPA) are phenolic, organic synthetic compounds used as an additive or monomers in the production of polycarbonate plastics and epoxy resins. BPA is a reproductive, developmental, and systemic toxicant, often classified as an endocrine-disrupting compound (EDC). BPA absorption into the body can result in the development of metabolic disorders such as low sex-specific neurodevelopment, immune toxicity, neurotoxicity and interference of cellular pathway. Therefore, the presence of BPA and its analogues in the environment has recently attracted global attention. This review provides evidence of BPA as a harmful compound and summarizes the current state of science on its removal. Several BPA removal techniques that mainly comprised of biological treatment, advanced oxidation and adsorption process were extensively studied. Biological treatment methods involved the use of biological agents such as enzymes (notably, laccase and peroxidase enzyme) to induce a degradation effect on bisphenols, and converting them into relatively harmless and less toxic compounds. Although, the removal efficiencies varied, the efficiencies for BPA by biological techniques was about 84%. Advance oxidation (AO) technique involves the use of highly reactive radical to degrade BPA. Hydroxyl (HO) and sulfate radical (SO₄^-) were the most commonly used radicals for BPA degradation. BPA removal by application of adsorption process were also discussed.