Use of South American species as bioindicators: The Ctalamochita River (Argentina) as a case of study

DRA. MONFERRÁN, MAGDALENA; DR. MARINO, DAMIÁN; DRA BERTRAND, LIDWINA; DRA AMÉ, MARÍA VALERIA

Estocolmo

Congreso; 6th YOUNG ENVIRONMENTAL SCIENTISTS MEETING; 2017

SETAC Europe

Aquatic organisms may be exposed to different water contaminants including pesticides, metals and pharmaceutical compounds from human activities. In South American countries, the information available about the use of native species as bioindicators of water contamination is poor. Our aim was to evaluate the potentiality of 2 South American native species, Palaemonetes argentinus (shrimp) and Potamogeton pusillus (macrophyte) to be used as bioindicators. Seven sites along Ctalamochita River (Argentine) were selected according to land use in different areas of the watershed: Pre and Post Santa Rosa de Ctalamochita city (S1 and S2), with low density of urban use (UU); Balneario Almafuerte (S3), with agricultural use (AU) and UU; Post Rio Tercero city (S4), with UU, AU and industrial use (IU); Pre Villa María city AU and IU (S5); Post Villa María city (S6) and Pre Bell Ville city (S7), both of them characterized by AU, UU and IU of land. Water and sediments samples were taken for determination of metals (in water, sediment), pesticides residues (in water) and pharmaceutical compounds (PhC, in water) as well as physical chemical parameters. After 96 h of exposure in cages, individuals were frozen with liquid nitrogen and maintained at - 80°C until determination of exposure, response and damage biomarkers (Bm). A spatial and temporal variation in water pollutants was observed along the river. The metal contamination increased from S1 to S7, while PhC were clearly related to UU and were accompanied by low values of a calculated water quality index (WQI). Also, pesticides were found in sites surrounded by intense farming activities. Water showed concentrations of Pb, Al, As, Ag, Hg, cypermethrin, chlorpyrifos and DDT higher than recommended for aquatic biota protection. Several sites presented a very high ecological risk especially due to Hg in sediments. An integrated biomarker response (IBR) was calculated with Bm measured in both organisms. Shrimp showed higher IBR values in S4 while the macrophyte presented the higher IBR values in S6 and S5. A principal component analysis showed an association between IBR value of shrimp and total concentration of pesticides and metals in water and the IBR values of macrophyte with PhC and metals in water as well as WQI. Finally, a generalized procruster analysis indicated an 86% of consensus between biotic and abiotic matrix. Our results would indicate the usefulness of both species as bioindicators of water contamination.