Urban soil pollution and assessment of human health risks in the industrialized city of Huelva

The city of Huelva in SW Spain is known to be affected by air pollution derived from industrial activities^1,2 and the soils surrounding the industrial estates contain anomalous concentrations of potentially toxic elements (PTEs)³. This study focuses on the urban soils of Huelva covering 33 sampling points in the principal public parks, playgrounds, and green areas. We evaluated potential contamination of the soils comparing Al-normalized values, contamination factor (CF) with respect to background values, and regulatory levels after analyzing the concentrations of PTEs (Cu, Zn, Co, As, Cr, Cd, Pb and Ni) in the topsoil, and further we assessed the potential toxicological effects using Lactuca Sativa L. bioassay and human exposure modelling. Al-normalized data highlighted anomalous high concentrations for Cu, Zn, As, Cr, and Pb. Moreover, CF values higher than one were found in 88% of the soils for Cu, 85% for Zn, 30% for Co, 45% for A36% for Cr, 100% for Cd, 45% for Pb, and 18% for Ni with elevated maximum concentrations (2083, 790, 16, 51, 153, 5.0, 293, and 32 mg/kg, respectively). The regulatory values for As (36 mg/kg) and Pb (275 mg/kg) were exceeded in soils of ten sampled urban areas. However, the germination and root elongation bioassays with Lactuca sativa L. did not show phytotoxicity in any of the tested soils, and health exposure modelling did not present risk for toxic effects nor for carcer. This study highlights the vicinity of the industrial area as a risk factor for the accumulation of PTEs in urban soils and previous studies corroborate this^3,4. We recommend monitoring of the urban soils of Huelva, further investigations on the soils that can be declared as polluted soils according to this study, and also to increase the number of toxicity bioassays with different organisms and to include different exposure routes for human health risk.

Acknowledgment

This work has been financed by the EMC21_00056 project granted by the Council of University, Research and Innovation of the Regional Government of Andalusia.

 

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