Global Biogeochemical Behavior of Mercury in the Aquatic Environment

ABSTRACT The Minamata Convention on mercury (Hg) suggests preventive measures to protect the aquatic environments and human health from Hg contamination. This review explores the biogeochemical cycling of Hg in the aquatic environments, associated human health risks, and the factors that influence their cycling. Literature reveals that Hg release pathways significantly affect its environmental dynamics, while climate‐mediated changes modulate Hg cycling by altering environmental conditions. Physical, chemical, and biological factors including water chemistry, land cover/land use changes, and watershed interruptions further influence Hg transport, bioavailability, and accumulation in the water bodies. Human health risk assessment findings showed that Africa, India, and Nigeria experience significant risks via ingestion and dermal routes, with hazard quotient (HQ) exceeding 1. Continent‐wise results of HQ followed the trend as: Africa > South America > Asia > Europe > North and Central America. Notably, the African continent exhibited the highest health risks (HQ ing : 21.70 for child and 14.53 for adults; HQ der : 0.22 for child and 0.075 for adults) compared to other continents. Global temporal analysis (1980, 1990, 2000, 2010, and 2020) revealed that only the 1990s showed HQ > 1, signifying greater health risks. The findings help in understanding the global Hg cycling, and its environmental and health risks, and underscore the need for targeted mitigation strategies. The review provides valuable insights for policy framework, assess the Minamata Convention, and guide future research on reducing Hg exposure and safeguarding human and ecosystem health.