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Abstract

In this work, the levels of DNA damage (8-oxo-7,8-dihidro-2'-desoxiguanosina, 8-oxodGuo) were evaluated in digestive glands of mussels exposed to different metals for 24 hours, as well as in coastal and farmed mussels. These experiments were carried out in order to evaluate the influence of uncontrolled abiotic factors on the production of 8-oxodGuo in mussels, since such lesions are extensively used as an indication of environmental contamination. Mussels exposed to lead or cadmium showed higher levels of oxidative DNA damage compared to the control group, and no difference was observed in mussels exposed to iron, indicating that metals can increase the levels of 8-oxodGuo in these organisms. On the other hand, wild mussels showed higher levels of 8-oxodGuo than farmed mussels, probably associated with high wave incidence and tidal oscilations. This data indicates that metals can increase 8-oxodGuo levels in mussels, but it also indicates that other environmental factors are capable of provoking such increases. Thus, for more appropriate use of DNA oxidative damage as a stress index related to the environmental contamination by pollutants such as metals, the sampling conditions should be considered, since this influences the observed results.