Heavy metals in soil, water sediment, and ambient PM2.5 across the Yangtze River economic belt: integrated environment risk identification and countermeasures

To explore the integrated pollution features of heavy metals in environmental multi-media throughout the Yangtze River Economic Belt (YREB) is of significance for national/local decision-makers to establish a sustainable development strategy. Distributions, enrichments, and induced environmental risks of typical toxic metals in soil, water surface sediment, and PM2.5 from the 11 provinces/municipalities of the YREB were studied based on bibliometric analysis. Compared with the background values, Cu, Zn, Cd, Pb, Hg, and Ni were enriched in both soil and surface sediments to a certain extent. Also, the provincial contents of As and Cr were higher than the standard limit of PM2.5. Spatially, the heavy metal pollution in environmental multi-media was distributed primarily in the central and southern parts of the YREB, specifically in the Hunan, Guizhou, Hubei, and Jiangxi provinces. The noncarcinogenic risks of As in soil and PM2.5 were the main contributor to the total risk. In the surface sediment, the average potential ecological risk for Cd and Hg reached Level V (very high ecological risk) and Level IV (high ecological risk), respectively, which is much higher than that for the other metals (Level I, low potential ecological risk). Consequently, Cd, Hg, and As were considered as priority control metals, and targeted risk management policies were recommended.