Mercury contamination in a changing climate: One health approaches to human, wildlife, and ecosystem protection

Mercury contamination exemplifies one of the most pressing global environmental health challenges of the 21st century, requiring integrated solutions that transcend disciplinary boundaries. This review provides the first comprehensive synthesis of mercury science through an explicit One Health lens, linking human, wildlife, and ecosystem health with the accelerating impacts of climate change. Mercury's global cycling and long-range transport generate interconnected exposure pathways, which simultaneously endanger human populations, biodiversity, and ecosystem integrity. The neurotoxic effects of methylmercury display remarkable cross-species consistency, driven by conserved mechanisms such as oxidative stress, mitochondrial dysfunction, and impaired neurodevelopment. Vulnerable groups, including pregnant women, lactating women, infants, children, populations with chronic comorbidities, indigenous communities, and apex predators, face disproportionate risks due to biomagnification and cumulative exposures. Despite regulatory advances, notably the Minamata Convention and its 2023 amendments, ongoing emissions and climate-driven perturbations continue to undermine management efforts. The present review identifies critical gaps in mixture toxicology, ecosystem-level consequences, and climate-mercury feedback. It proposes integrated interventions that simultaneously safeguard human health, wildlife populations, and environmental quality. By situating mercury contamination within the One Health framework, the review highlights the urgent need for coordinated transdisciplinary action to mitigate risks and advance planetary health.