Sensitivity of selenastrum capricornutum, Daphnia magna and submttochondrial particles to tributyltin

Abstract

The purpose of this study was to evaluate the sensitivity to tributyltin (TBT) of two aquatic organisms belonging to two different levels of the feeding chain: Selenastrum capricornutum alga and Daphnia magna crustacean. The EC₅₀ value at 96 h for Selenastrum capricornutum and the ones at 24 h and 45 h for Daphnia magna with relative confidence intervals and NOEC values were calculated. A partial stimulus effect was observed both for alga and crustacean at very low TBT concentrations. The data obtained were compared both with toxicity TBT values, obtained from bibliography, concerning invertebrates, fishes and algae and with the results obtained by a new in vitro test utilizing submitochondrial particles (SMP). The response of SMP to TBT confirmed that the inhibition of the respiratory functions is one of the mechanisms by which the TBT causes toxicity to intact cells as well as to more complex organisms.

Keywords:

• Tributyltin toxicity
• Daphnia magna
• Selenastrum capricornutum
• submitochondrial particles
• toxicity test