Eel (Anguilla anguilla) and brown trout (Salmo trutta) target species to assess the biological impact of trace metal pollution in freshwater ecosystems

Copper, lead, and cadmium pollution were measured in water and sediments of two Northern Spanish rivers: Piles and Pigüeña. Liver contents of these heavy metals were analyzed in two fish species (eel, Anguilla anguilla, and brown trout, Salmo trutta) collected from the same locations. Significant levels of heavy metal pollution were found in a 38% of fish that are potential catches for sport fishermen. The results indicate that adult eel could be a good metal bioindicator if sampled at a homogenous age. In contrast, brown trout could be considered as a bioindicator only during the first year of life.