Toxicity evaluation and preparation of CoWO4 nanoparticles towards microalga Dunaliella salina

The increasing use of nanoparticles and their many applications increases the likelihood of their presence in the environment. This possibility of presence necessitates the study of the effect of these substances on aquatic species. In this research, CoWO4 nanoparticles were synthesized by the ultrasonic method. Various conditions in the synthesis process were investigated to obtain the appropriate size of the nanoparticles. After selecting the optimum particles, these nanoparticles were used to investigate their effect on the growth of Dunaliella salina. For this purpose, the algal cells were subjected to three different concentrations of nanoparticles (15, 30, and 60 mg/L). The study results on algae growth parameters showed that these parameters depend on the value of nanoparticles. At 15 and 30 mg/L concentrations of the nanoparticles, numbers of cells, specific growth, biomass, and pigments showed a significant boost compared to the mentioned parameters of the control treatment. Measurement of malondialdehyde (MDA) showed that this parameter was directly related to the increase in the concentration of nanoparticles. At 60 mg/L of the nanoparticles, the MDA level was higher than the control and other treatments. This increase reflects the destructive effect of the nanoparticles on algal cells. Finally, the results showed that algae could be useful for studying the environmental effects of nanoparticles and their safety.