Comparative Baseline Levels of Heavy Metals and Histopathological Notes in Fish Fromtwo Coastal Ecosystems of South-West of Spain

Abstract

This work reports the comparative study of heavy metal water concentrations from<br />two coastal ecosystems ofCadizGulf (SWSpain): Bay of Cadiz and Ria ofHuelva estuary in samples<br />taken on years 1999-2000. Sampling zones showed different heavymetal levels. Statistical analysis<br />of dissolved trace metal concentrations (Cu, Zn, Cd and Pb) showed significant differences between<br />Huelva and Cadiz zones based on the Cu level, with a marked seasonal factor and different metal<br />sources (Industrial, geological, urban,...), observing a higher Cu concentration in Ria de Huelva<br />respect to Bay of Cadiz. On the other hand, to evaluate the pollutant effects on aquatic biota, a<br />histopathological analysis have been conducted in specimens of flat fish, Solea senegalensis from<br />both zones. Lesions weremore severe in fish fromRia ofHuelva, being themost significant alterations:<br />gill hyperplasia, fusion of secondary lamellae, disorganization of the hepatic parenchyma, cellular<br />hypertrophy and vascular congestion in liver and tubular occlusion, loss of interstitial tissue and<br />lipid-like vacuoles in kidney. Obtained results are useful as reference data for future environmental<br />monitoring studies in these zones where to establish a heavy metal concentration temporal trend<br />would be necessary.