The Aznalcóllar mine accident (Seville), in April 1998, was an ecological and socioeconomic catastrophe with important international impact. The remediation and restoration of the area affected by the mine spill transformed a devastated and contaminated area into the current Guadiamar Green Corridor Protected Landscape. Despite the successful recovery of the affected area, residual contamination is still present.
One of the main threats from the mine spill was the presence of potentially toxic trace elements, such as As, Cd, Pb and Tl, in the contaminated soil. Therefore, it exists a risk of toxicity due to their possible transfer from the soil to the food chain, since the contents of these elements at high concentrations can be harmful to livestock and wild animals, as well as to human health. A research team of the IRNAS-CSIC led by José Manuel Murillo, in collaboration with the researchers Paula Madejón, María Teresa Domínguez and Engracia Madejón, has published the book chapter entitled “Risks for the food chain in the Guadiamar Green Corridor”. In this chapter, most of the studies carried out in the Green Corridor, dealing with the transfer of trace elements at different levels within the food chain, during the 20 years since the accident are collected. In addition, the corresponding potential risks of toxicity for animals and for human consumption are evaluated.
Three relevant case studies, conducted by IRNAS researchers, are described in more detail: the potential toxic effect on the horses that graze in the Green Corridor, the accumulation of trace elements in land snails, and the transfer and accumulation of these elements in mushrooms. Both snails and mushrooms are wild foods that can be collected in the Green Corridor and consumed by local residents.
Finally, it is clearly explained why the neighbours of the close villages of the Green Corridor must not collect any food product from the contaminated area, for human consumption.
Madejón P, Madejón E, Domínguez MT, Murillo JM (2020). Riesgos para la cadena trófica en el Corredor Verde del Guadiamar. In: P Madejón y T Marañón (eds.), Recuperación de suelos y provisión de servicios ecosistémicos en el Corredor Verde del Guadiamar, pp. 113-135. Editorial CSIC, Madrid.