Biochemical bio markers of pollution in Algerian mouse (Mus spretus) to assess the effects of the AznalcÓllar disaster on Doñana Park (Spain)

Abstract

On April 25, 1998, a tailings dam of the Aznalcóllar pyrite mine partially collapsed and released to the Guadiamar river acidic water (pH < 3) and mud containing toxic metals (Fe, Zn, Pb, As, Cu, Sb, Co, Tl, Bi, Cd, Ag, Hg, Sr), threatening the Doñana National Park, a Spanish wildlife reserve. To assess possible biological effects in terrestrial ecosystems, biochemical biomarkers have been assayed for the first time in Algerian mice (Mus spretus), a non-protected and free-living species, from several areas of Doñana and Guadiamar. Biomarkers assayed responded to different types of contaminants: I-metals and oxidant compounds (Se-glutathione peroxidase (SeGSHPx) and antioxidant activities, malondialdehyde (MDA), and glutathione redox status); II-Aromatic chemicals (ethoxyresorufin-O-deethylase (EROD) activity); III-Compounds of both types (glutathione-S-transferase (GST) activities). Before the Aznalcóllar spill (October 1997), mice from the 'Brazo de la Torre' had SeGSHPx and EROD activities close to animals from the Huelva Industrial Park, suggesting similar levels of oxidant and aromatic contaminants at both sites. Six months after the spill (October 1998), mice from the lower Guadiamar areas ('Cangrejo Grande' and 'Brazo de la Torre') also showed significant increase of soluble and microsomal GST activities, and altered levels of several antioxidant enzymes. Thus, the spilled chemicals could have induced further biological effects in mice from the exposed areas. Although no significant responses to contamination were found after the spill at Doñana core, further investigations should be carried out to monitor the situation.