The toxicity of binary mixture of Cu (II) ion and phenols on Tetrahymena thermophila.

The toxicity of binary mixture of Cu(2+) and phenols (phenol; o-nitrophenol; m-nitrophenol; p-nitrophenol) was evaluated using Tetrahymena thermophila as the model organism, by microcalorimetry, optical density, field emission scanning electron microscope (FESEM) and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). The growth curves and metabolic properties of Tetrahymena exposed to Cu(2+) and phenols were monitored by microcalorimetry. Binary mixture toxicity changed with the concentration of Cu(2+)/phenols and the order of toxicity was Cu(2+)/phenol<Cu(2+)/m-nitrophenol<Cu(2+)/o-nitrophenol<Cu(2+)/p-nitrophenol. The results of FESEM and ATR-FTIR also indicated that Cu(2+)/phenols had a great effect on cell cortex and flagellum. A synergistic effect was noted between Cu(2+) and phenols on Tetrahymena.