Assessment of the content of potentially hazardous elements in agricultural soils of several municipalities in the Province of Valencia (Spain)

Environmental research and public health face significant challenges when addressing the study of agricultural soils. Preserving soils and crops is crucial for food quality, as well as for advancing progress toward the Sustainable Development Goals and fulfilling the objectives of the 2030 Agenda. Agricultural soils in the Valencian region are under strong pressure from human activities (industrialization, urban development, intensive agriculture, and tourism). The presence of high concentrations of potentially hazardous elements (PHEs) such as As, Cd, Co, Cr, Cu, Ni, Pb, and Zn poses a risk in agricultural soils due to their toxicity, persistence, and ability to bioaccumulate in crops, potentially entering the food chain.

In this study, 25 agricultural soil samples from 17 municipalities in the L’Horta and La Ribera districts (Valencia) were analyzed and evaluated. The determination of PHEs was carried out by microwave-assisted digestion in a strongly acidic medium and quantified by ICP-OES. In addition, regulatory standards and contamination indices were applied to assess soil quality from a contamination perspective. Concentrations of Cd, Cr, Cu, Pb, and Zn in some soils exceeded the reference values established by the Autonomous Communities of Aragon, Catalonia, and Madrid. Contamination ranged from moderate to severe and was associated with anthropogenic sources. Furthermore, the application of the indices confirmed the existence of a potential contamination risk, with Cu, Pb, Sr, and Zn showing the highest risk levels.

These findings highlight the need to adopt soil management and monitoring measures in the most affected areas in order to prevent risks to food safety and public health.