Assessing contamination from maritime trade and transportation on Iberian waters: Impact on Platichthys flesus

Abstract

Maritime trade and transportation of hazardous and noxious substances (HNS) have been increasing in European waters, augmenting the risk of accidental spills from ships or in harbours. Despite their reported toxicity and hazardousness, information on HNS levels in the aquatic environment is still lacking. Therefore, an assessment combining a chemical and a multi-biomarker evaluation on HNS contamination was done in NW Iberian estuaries of Rivers Minho, Lima and Douro using Platichthys flesus (flounder). Of the twenty-five HNS measured, fifteen were found in flounder liver and muscle, and a few in sediments, though at generally low levels. Principal component analysis produced a clear distinction among sites, with Douro River estuary arising as the most impacted. Oxidised proteins and antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase) were the biomarkers contributing to site discrimination. Correlations between biomarkers and HNS levels provided important baseline information for the study area and potential biological effects of HNS on this sentinel species.