Biomonitoring of Doñana National Park using the Algerian mouse (Mus spretus) as a sentinel species

Abstract

The aim of this work was to analyse the biological effects of man-made activities on Algerian mice (Mus spretus Lataste, 1883) living in Donana National Park (DNP) and its surroundings (SW Spain). Biomonitoring was performed, before and after the accident in the Aznalcollar pyrite mine (April 1998), to investigate the environmental risk due to the release of chemical waste in the Guadiamar River, which reaches the DNP marshlands. Mice (N=420) were collected from different sites, inside and outside the Park, over a period of five years (1995-1999). The experimental design consists of using different biomarkers to detect the possible biological effects induced by xenobiotics in somatic and germ cells. Micronucleus test, sperm abnormality assay and Comet assay were performed to assess genotoxic damage. In addition, concentrations of some heavy metals (Pb, Cd, Zn, Cu) and arsenic were measured in animal livers. Data obtained indicate that the biological damage observed in mice is the effect of the contaminants released by the flooding and toxic spill after the accident of the Aznalcollar mine. In particular, micronuclei frequencies were significantly higher in mice collected from the sites outside the Park, directly affected by the spread of the contaminated mud, compared to those from areas inside the Park not directly affected. Furthermore, results showed that a chronic contamination was present also before the mining accident in some areas of DNP, and this effect was still present one year after the disaster. Therefore, the study suggests that biomonitoring had to be carried out in Doñana to determine the long-term biological effects of environmental pollution and the risk for the ecosystems in this protected area. In conclusion, on the basis of the important results found in this multidisciplinary study, we should conclude that the collaboration of different competences is desirable to create a pilot center for territorial monitoring.