Non-essential metals in water, sediments and tissues of fish from different trophic levels in Río Tercero Reservoir (Córdoba, Argentina).

GARNERO, P; MONFERRÁN. M.V; M. A. BISTONI

Buenos Aires

Congreso; SETAC Latin America 11th Biennial meeting; 2015

SETAC

Non-essential metals are found in the environment and have not any biological activity associated. The continuous increase of these metals by anthropogenic activities, turn them in contaminant substances. These elements are characterized by a long persistence, high toxicity and a poor degradation. When they enter into the aquatic environment, they are absorbed by the sediments, and can be accumulated by the aquatic organisms, among them fish. These organisms can take metals from water through the gills, skin or intestine by the intake of contaminated food. The aim of this study was to determine non-essential metals concentration in water, sediments and organs of fish (Rhamdia quelen, Oligosarcus jenynsii, Odontesthes bonariensis) from different trophic levels in Río Tercero Reservoir. Sampling was conducted in winter season at two sampling sites with different anthropogenic impact (tourist and drainage channel of the Embalse nuclear plant). The metals concentration (As, Cr, Cd, Hg, Pb and Sr) in abiotic matrices (water and sediment) and different organs (gills, intestine, live and muscle) of each species was determined by Q-ICPMS. In water, it was registered Pb and Sr. In sediments, all metals were registered except Cr and As. There were no differences between sampling sites in the abiotic matrices. With regards to fish, all metals were registered in fish organs. The measured concentration of the metals varied with the fish species and with the organs. In R. quelen, intestine accumulated the highest levels of all studied metals except for Hg and As which presented the highest levels in gills and liver respectively. O. jenynsii and O. bonariensis showed no significant differences in metals accumulation between organs, except Sr, that presented the highest concentration in gills for both species, and Hg and Sr that registered the highest levels in liver of O. jenynsii and O. bonariensis respectively. If metals concentration in all organs is considered then R. quelen (?fish that frequent the bottom?), was the species that more metals accumulated, because it?s in direct contact with the sediment, matrix where the metals are mainly concentrated. On the other hand, O. jenynsii and O. bonariensis presented the lowest accumulation of these elements, being the latter, the one with the least metal accumulation.. These species inhabit "open waters", being predator and planctophagous respectively. The different habits that have the studied species would impact on the differential accumulation of non-essential metals in the analyzed organs.