Temporal dynamics of mercury exposure and associated health and economic burdens in China

Mercury is a global highly toxic pollutant linked to neurodevelopmental impairments and cardiovascular risks. However, despite being the world's largest anthropogenic mercury emitter, China has lacked systematic human biomonitoring evidence to evaluate long-term exposure and health impacts. By integrating nationwide biomonitoring datasets (extracted from 158 articles) with machine learning modeling, this study provides the first comprehensive national assessment of temporal trends in human mercury exposure and their associated health and economic burdens in China. According to the present study, average hair methylmercury (MeHg) concentrations declined from 0.257 μg/g in 2002-2005 to 0.194 μg/g in 2014-2017, followed by a slight rebound to 0.212 μg/g in 2018-2021. Spatial hotspots became less extensive, indicating major progress in mercury control. While MeHg-associated intelligence quotient (IQ) loss decreased over time, acute myocardial infarction mortality increased due to rising baseline cardiovascular risks, with demographic aging and diet shifts further threatening progress. As a result, absolute economic losses tripled, though their share of national GDP declined. These findings highlight both the achievements and emerging challenges of mercury risk management in China and establish a quantitative nationwide evidence base for evaluating the implementation of the Minamata Convention and guiding future mercury control strategies at both national and global levels.