Risk-Based Identification of Priority Control Factors of Soil Potentially Toxic Elements (PTEs) in Typical Agricultural Areas of Pengzhou, China

Rapid industrialization and urbanization have drawn increasing attention to the problem of agricultural potentially toxic element (PTE) pollution. Identifying priority control sources and elements through risk-based quantification of farmland PTE pollution sources is pivotal for effective soil pollution prevention and control. By investigating agriculture fields in Pengzhou, China, the pollution sources of soil PTEs (Cr, Cu, Ni, Zn, Pb, Cd, Hg, and As) were identified and quantified by a positive matrix factorization (PMF) receptor model, and their ecological and human health risks were quantitatively assessed by combining risk exposure with source profiles. The results revealed that point percentages of soil Zn, Cr, Ni, Cu, and Cd concentrations exceeding their corresponding environmental risk screening values were 0.98%, 2.94%, 16.67%, 5.88%, and 80.39%, respectively. The soil PTEs originated from atmospheric deposition, industrial emission, farming activities, and natural sources, which accounted for 22.73%, 39.94%, 24.43%, and 12.90%, respectively. Ecological and human health risk assessments showed that Cd contributed the most to ecological risk, whereas Cr posed the greatest human health exposure risk. Source-oriented risk assessment indicated that agricultural activities predominantly contributed to ecological risk, while industrial emissions primarily affected human health. These findings indicated that the source contributing most to soil PTE concentrations may not necessarily pose the greatest risk. Overall, agricultural and industrial sources, along with Cd and Cr, were identified as priority targets for control. Policies promoting scientific use of fertilizers and pesticides in the agricultural sector, along with technological upgrades and emission controls in the industrial sector, should be implemented to mitigate exposure risks and promote sustainable soil health.