Antagonistic effects of binary mixture of titanium dioxide nanoparticles and lead on biomass and oxidative stress in exposed Chloroidium ellipsoideum (Gerneck)

Sub-lethal bioassay was performed on Chloroidium ellipsoideum to monitor the changesin the algal biomass and antioxidant activities associated with Titanium dioxide Nanoparticles (TiO2 NPs) and Lead Pb(II). The results showed that there was significant (p < 0.05) decrease in biomass (density, chlorophyll a and b) of Chloroidium ellipsoideum as a result of adsorption of Pb(II) by TiO2-NPs. However, the binary mixtures of the chemicals significantly increased antioxidant activities (SOD and MDA) of the alga. Furthermore, the study revealed an antagonistic (CI >1) effect of the binary chemicals on the biomass and antioxidant activities of the alga. Based on the study, it was shown that the co-exposure of TiO2 NPs and Pb(II) decreased the Pb(II) bioavailability causing antagonistic effects on biomass and antioxidant activities in Chloroidium ellipsoideum