Can interspecific interactions in freshwater benthic macroinvertebrates modify heavy metal effects?

ANDRADE, VICTORIA S.; WIEGAND, CLAUDIA; GAGNETEN, ANA M.; PANNARD, ALEXANDRINE; PISCART, CHRISTOPHE

San Luis

Congreso; VII Congreso Argentino de la Sociedad de Toxicología y Química Ambiental de Argentina (SETAC, Capítulo Argentino); 2018

The aim of this study was to assess how inter-specific interactions in freshwater benthic macroinvertebrates can modify heavy metal effects in term of bioaccumulation and oxidative stress enzymes. We exposed three macroinvertebrate species in microcosms to sediments collected from the Sélune River (Normandy, France), which has an affluent contaminated with heavy metals (Yvrande river). Sediments were collected upstream (C0) and downstream (C2) Yvrande confluence and C1 was the combination of both. The experiment lasted 7 days at 20°C and 14/10h day night regime. The macroinvertebrates were selected according to their functional feeding group: the omnivorous amphipod Echinogammarus berilloni, the sediment feeder Oligochaeta Tubifex tubifex and the filter feeder Pisidium sp. Combinations of organisms: 1) biofilm; 2) biofilm-E. berilloni; 3) biofilm-Pisidium sp.; 4) biofilm-E. berilloni-Pisidium sp. and 5) biofilm-E. berilloni-Pisidium sp.-T. tubifex. Heavy metals concentration in water and sediment were assessed at the beginning and at the end of the experiment while the content in animals was determined in non-exposed organisms and in exposed organisms at the end of the experiment. Catalase activity also was recorded. Cr and Pb concentration in C2 water were significantly higher in the combination of two and three animals than biofilm alone, concentration of Cu in C2 water was significantly higher in the combination of two animals than biofilm alone (p