Deciphering media-specific differentiation of REY geochemical behavior and health risks regulated by geogenic and...

As emerging contaminants, rare earth elements and yttrium (REYs) raise environmental concerns due to their persistent release. However, a holistic understanding of their disparate geochemical behavior, sources, and health risks across multiple environmental media under complex geogenic and anthropogenic interference remains limited. Thus, this study integrates geochemical fingerprinting, quantitative source apportionment, and health risk assessment in a representative resource-based area to explore source- and environmental media-specific discrepancies in REY geochemical characteristics and health risks. Results revealed distinct fractionation patterns and anomalies across media, ubiquitously driven by industrial and agricultural inputs, yet mediated separately by soil organic matter/weathering and groundwater carbonate complexation. Soil REYs originated from comparable contributions of geogenic (56.1 %) and anthropogenic (43.9 %) sources, while groundwater REYs were dominated by anthropogenic sources (77.4 %). Deterministic assessment indicated negligible REY-induced health risks, with exposure primarily attributed to the maize grains and soils. Probabilistic analysis revealed that bedrock outcropping areas had higher risks from REY-enriched bedrocks than from heavy industries, while maize grain-associated REY risks were more sensitive to bedrock geochemistry and emerging industrial contamination. In the plain areas, soil-associated REY risks were dominated by heavy industrial contamination, while those from groundwater were controlled by agricultural activities. These findings are critical for targeted REY contamination control, aiding the global sustainable transition of emerging industries.