Toxicity Effects of SiO2 Nanoparticles on Green Micro-Algae Dunaliella Salina

New extension of nanoparticles used in the last two decades and hence, entrance of them to industrial and non-industrial sewage necessitate study of probable effects of these materials in aquatic ecosystems. This research was performed in order to determine the toxicity effect of silica dioxide (SiO2) nano particles on Dunaliella salina green algae in laboratory conditions. SiO2 nanoparticle is one of the best full-used nano particles which have application in industries like production of ceramics, plastics, glass, cosmetics, medicine and paper. Dunaliella algae because of having economic value and different biochemical composition is used as complements with natural origin in food and pharmacology industries. For toxicity determination of this material, the experiment was performed according to O.E.C.D standard method. Experiments on Dunaliella were performed for 72 hours with 7 treatments, two controls and three replicates in each treatment and daily counting of cells in each tube. Counting cell algae population was done by microscope on a Thoma counting slide. For data analysis, probit analysis, Excel software and SPSS21 were used. The 72 hours NOEC, EC90, EC50 and EC10 were calculated. The amounts of 72 hours are EC10 =5.37.10-5 , EC50 = 0.169 , EC90 = 512.86, NOEC = 1.6×10-2 mg/l. Cell compression noticeably decreased (P < 0.05) by increasing nanoparticle concentration and silica oxide nanoparticle caused to inhibit growth in Dunaliella species.