Zebrafish model in climate change toxicology assessment: unraveling the synergistic effects of abiotic stressors and environmental pollutants

This review explores the multifaceted impacts of climate change-driven environmental stressors, particularly rising water temperatures and acidification, on aquatic life, using zebrafish (Danio rerio) as a model organism. As global climate change accelerates, aquatic ecosystems are increasingly subjected to complex interactions between abiotic stressors and anthropogenic pollutants such as heavy metals and microplastics. This review examines how climate-induced shifts alter the physicochemical properties and toxicity profiles of coexisting contaminants. These shifts can further amplify adverse biological effects. Furthermore, we emphasize the indispensable role of the zebrafish model in elucidating the underlying mechanisms of these toxicological interactions. These mechanisms range from oxidative stress and apoptosis to epigenetic modifications. This mechanistic insight can inform the development of effective mitigation strategies to address future environmental crises. Importantly, this review also highlights emerging evidence indicating that climate-driven stressors can induce persistent epigenetic reprogramming. Such reprogramming may extend toxicological consequences beyond the immediate exposure period and into subsequent developmental stages. Recent studies provide compelling evidence that climate change acts as a potent “toxicity multiplier” in aquatic ecosystems. Research utilizing zebrafish has demonstrated that environmental shifts, particularly warming and acidification, significantly amplify the bioavailability and physiological impact of coexisting pollutants, such as heavy metals and plastics. These interactions result in compounded biological damage that exceeds the additive effects of individual stressors and manifests as heightened oxidative stress, dysregulated apoptosis, and severe morphological defects in zebrafish. Importantly, recent advances have demonstrated that these climate-driven stressors can induce stable epigenetic alterations, thereby providing a mechanistic basis for long-lasting developmental, physiological, and behavioral effects that persist across life stages and may extend to subsequent generations. Collectively, these findings suggest that epigenetic and intergenerational effects are central features of climate change toxicology, underscoring that interactions between climate-induced stress and chemical pollution pose a complex, multidimensional threat to aquatic life and demand an integrative mechanistic understanding.