Regional-scale monitoring of coastal contamination. Nutrients and heavy metals in estuarine sediments and organisms on the coast of Galicia (northwest Spain)

We determined background levels of heavy metals in sediments and biota of estuarine environments and nutrient reference levels in sediments of the Galician coast. This region is characterized by having ria-type estuaies. The determination of these levels, which were affected by the geological heterogeneity of the area, was the basis that let us evaluate the contamination status of this coast. The contamination factors calculated for different metals evidenced few sites wioth severe contamination. The potential ecological risk approach, used to evaluate the overall degree of pollution based on the metal levels in the sediments, agreed with this conclusion.