Research progress on the toxic effects of polychlorinated biphenyls and its hydroxylated metabolites

Typical persistent organic pollutants (POPs) in the environment - polychlorinated biphenyls (PCBs) – have been restricted in daily production activities due to their endocrine-disrupting effects and “three-induced” toxicities (carcinogenic, teratogenic, mutagenic) and so on. However, because PCBs are difficult to degrade and tend to accumulate persistently in the organisms, they can undergo further metabolic reactions to form second-generation POPs, such as hydroxylated polychlorinated biphenyls (OH-PCBs) and methylsulfonyl polychlorinated biphenyls (MeSO2-PCBs). These metabolites may exhibit stronger toxicological effects than their parent compounds, leading to their persistent presence in the environment and making them difficult to eliminate completely. Currently, there is limited research on whether co-exposure to PCBs and their metabolites in the organisms results in synergistic or antagonistic interactions, as well as the mechanisms underlying their potential health risks. Therefore, this review focuses on PCBs and their significant metabolite, OH-PCBs, reviewing their toxicological mechanisms in the organisms. Additionally, it explores the application prospects of emerging pollutant monitoring methods in areas such as risk identification, property assessment, toxicity prediction, and assisted removal. The aim is to point out new research directions and insights for the identification and assessment of emerging pollutants in the environment, so as to cope with the increasingly serious environmental pollution problems more effectively.