BIOACCUMULATION OF TRACE ELEMENTS IN FRESHWATER JUVENILE FISHES: IMPLICATIONS ASSOCIATED WITH ESSENTIAL FISH GROWING HABITAT

LLAMAZARES VEGH, SABINA; AVIGLIANO, ESTEBAN; VOLPEDO, ALEJANDRA V.

Seminario; 1st Seminar of the Association of Chemistry and the Environment (ACE); 2021

Association of Chemistry and the Environment - ACE a.s.b.l.

Metal and metalloids accumulation in fish depends on both the chemical properties of theelements and different factors such as ecological needs, the physiological state, size and ageof individuals, as well as the life history and feeding habits. This study assessed theconcentration, bioconcentration, and bioaccumulation of As, Cd, Co, Cr, Cu, Mg, Mn, Ni,Pb, and Zn in juvenile fishes of several species in the Lower Paraná River (Argentina), themost extensive floodplain from the Plata Basin. The floodplain is crucial for thereproduction and growth of migratory species such as Prochilodus lineatus, Megaleporinusobtusidens, and Salminus brasiliensis, which complete their life cycle in this environment.Individuals were sampled for nitrogen stable isotope, and trace element analysis in muscletissue, water, and sediment was analyzed. The results show that all the studied speciesbioaccumulate Cr, Mg, Ni, and Zn. In particular, Brycon orbygnianus and Pimelodusmaculatus presented the highest bioaccumulation factor for Cr. A biodilution of Co throughthe food chain was observed. No positive correlation was found between elementconcentration and trophic level, but we observed significant differences between trophicguilds (herbivorous, omnivorous, and carnivorous). Our findings suggest that feeding habitsdetermine trace element concentrations. Further studies are necessary to establishdifferential behavior between different species within the aquatic web, particularly in thefloodplain of the Paraná, which is a crucial nursery area for most commercially importantfishes from the Plata Basin.