Metal contamination in Portman Bay (Murcia, SE Spain) 15 years after the cessation of mining activities

J Benedicto,C Martínez-Gómez,J Guerrero,A Jornet,C Rodríguez

doi:10.7773/cm.v34i3.1391

Abstract

To evaluate the state and temporal trends of the residual metal contamination caused by the dumping of mine tailings into Portman Bay (SE Spain) during the 20th century, concentrations of Hg, Cd, Pb, Cu, Zn, and As in wild mussels (Mytilus galloprovincialis) were studied over the period 1991–2005. The results show significant downward trends (P < 0.05) in the concentrations of Hg, Cu, Pb, and Zn. Nevertheless, trace metal concentrations in mussels from Portman in 2005 were higher than the reference concentrations established for the coast of Murcia and the Spanish Mediterranean littoral, the only exceptions being Cu and As. Red mullets (Mullus barbatus) caught at Portman in 1990 and 2004 presented higher levels of Hg, Cd, and Pb, in comparison with other areas of the south and southeastern coast of Spain. The results indicate that Portman Bay is still one of the areas most heavily contaminated by Pb and Cd along the Mediterranean coast of Spain 15 years after the cessation of mining activities.

Highlights

IntroducciónThe presence of metals in the marine environment, caused by both natural processes and anthropogenic activities, is cause of great environmental concern all over the world due to their persistent and toxic nature, bioaccumulation power, and potential risk for human health and marine organisms (Rainbow 1995)
We evaluated the current state of metal contamination in mussels and red mullets, in order to determine whether organisms inhabiting the surroundings areas of Portman Bay are still subject to higher metal exposure than in other areas of the southern and southeastern coast of Spain
Metal concentrations in red mullets caught in Portman Bay in 2004 were not significantly different (P > 0.01) than those measured in 1990 (Rodríguez et al 1994)

Summary

Introduction

IntroducciónThe presence of metals in the marine environment, caused by both natural processes and anthropogenic activities, is cause of great environmental concern all over the world due to their persistent and toxic nature, bioaccumulation power, and potential risk for human health and marine organisms (Rainbow 1995). Together with atmospheric depositions, urban runoff, and industrial/urban effluents, have generated serious environmental problems of metal contamination in the marine environment (Martínez-Frías 1997, Pirrie et al 1997, Vasquez et al 2000, David 2002, Riba et al 2005, Martín-Díaz et al 2006). Junto con los depósitos atmosféricos, la escorrentía y los efluentes urbanos e industriales, han generado serios problemas ambientales de contaminación por metales en el medio marino (Martínez-Frías 1997, Pirrie et al 1997, Vasquez et al 2000, David 2002, Riba et al 2005, Martín-Díaz et al 2006). More than 80% of Portman Bay is filled with tailings, corresponding to 70 ha previously occupied by the sea

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Conclusion