Bioassay of Zinc Oxide Nanoparticles Exposed-to Reactive Blue 29 by Using Daphnia Magna

The problem of the environmental pollution by nanoparticles, which have recently entered the cycle of industries process in Iran, is very important and can be prevented with applying the proper management approaches. One of the most practical compounds is ZnO nanoparticle. In the present study the (lethal concentration-50) LC50 24hr and 48hr of ZnO nanoparticles exposed-to reactive blue 29 were determined by bioassay using Daphnia This study was carried out in lab scale. In the first stage Daphnia were cultured. Then desired concentrations were obtained by detection range tests, each concentration was studied for 24 and 48 hours for ZnO nanoparticles and ZnO nanoparticles exposed-to reactive blue 29. Testing method was based on standard methods. The average mortality rate for experiments were analyzed using Probit analysis in SPSS ver. 16, and LC50s were determined. The obtained data from the Probit analysis were used in Excel software to plot graphs. The obtained results showed that the LC50-24h and LC50-48h of ZnO nanoparticles exposed-to reactive blue 29 are 1.8 and 1.2 mg/l respectively. ZnO nanoparticles exposed-to reactive blue 29 had more toxicity than ZnO nanoparticles non-exposed-to reactive blue 29. Based on obtained results, longer exposure time can result in less LC50 value, meaning that the toxicity effect of ZnO nanoparticles on Daphnia was higher, therefore, toxicity of ZnO nanoparticles exposed-to reactive blue 29 is dependent upon exposure time to Daphnia.