Abstract
Widespread contamination of Chinese farmland soils by potentially toxic elements (PTEs) may pose emerging threats to food safety and human health. However, comprehensive nationwide investigations of pollution levels, trends and health risks are lacking. In this study, data from major agricultural regions across 10 Chinese provinces from 2007 to 2021 was analyzed to assess the concentrations of 8 key PTEs (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), lead (Pb), nickel (Ni), and zinc (Zn)) and determine spatial patterns, temporal accumulation, and current and future human health risks. The results showed that the average concentrations of Cd, Hg, Pb, Cu, Zn, Ni, Cr and As were 2.69, 2.47, 1.49, 1.14, 1.01 0.93, 0.89, and 0.89 times greater than their corresponding background values in China. Spatio-temporal analysis revealed increasing As pollution over time across provinces, with some areas reaching moderate-high pollution status. The geo-accumulation and pollution indices identified Cd, Hg, and Pb as the most heavily contaminated elements, with ingestion being the major exposure pathway increasing non-cancer and carcinogenic hazards. The study provided a baseline inventory of PTEs accumulation in Chinese farmland soils and evidence of potential health risks to guide priority areas for pollution control and soil remediation nationwide.