Environmental contaminants present a significant concern owing to their pervasive distribution and their capacity to induce molecular and cellular damage. Among these, polycyclic aromatic hydrocarbons and heavy metals are of particular importance, as numerous compounds within these categories are classified as carcinogenic by the International Agency for Research on Cancer (IARC). It is crucial to understand the mechanistic basis of their genotoxicity to elucidate how environmental exposures contribute to genotoxicity. In this regard, biochemical, cytogenetic, and DNA integrity biomarkers have become essential tools for detecting biological responses and unraveling toxicodynamic pathways. Despite these advancements, most existing evidence derives from studies assessing single compounds; however, real-world exposures typically involve complex mixtures in which polycyclic aromatic hydrocarbons and heavy metals frequently co-exist. Mixtures can produce interaction effects (synergistic, additive, or antagonistic) that significantly alter the extent and nature of genotoxic damage. Therefore, risk assessments based solely on isolated exposures may not adequately reflect environmentally relevant scenarios and could underestimate potential hazards. Overcoming this limitation necessitates research strategies that incorporate validated biomarkers to evaluate combined exposures. These methods improve understanding of interaction mechanisms, quantify mixture-induced DNA damage, and clarify individual roles of pollutants, enhancing human health risk assessment.
Alarcón-Herrera et al. (Sun,) studied this question.