Biomarkers of contamination in coastal aquatic organisms of Rio de la Plata (Argentina).

The study and development of bioanalytical methodologies applied to appropriated indigenous freshwater sentinels were proposed for early detection of xenobiotics exposition in natural waters. In this sense, metallic uptake was correlated with the expression of biomarkers of contamination such as metallothioneins in studies developed in the Mediterranean and Baltic seas. The results obtained from the development and optimization of biomarkers in characteristic sentinels of the Rio de la Plata coast in acute exposition assays to heavy metal were shown in the present study. Bivalves mollusk (Corbicula fluminea and Limnoperna fortunei), and aquatic plants (Schoenoplectus californicus, Sagitaria montevidensis and Pistia stratiotes) were selected as sentinels. The kinetic uptake of copper and cadmium and the expression of cytosolic proteins were particularly analyzed. Metal content was determined by atomic absorption spectrophotometry, and the protein pattern modification was assessed by using SDS-PAGE electrophoresis, in Tristricine system, followed by coomasie blue and silver staining.