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

Abstract

<span class="fontstyle0">New extension of nanoparticles used in the last two decades and hence, entrance of them to industrial<br />and non-industrial sewage necessitate study of probable effects of these materials in aquatic ecosystems.<br />This research was performed in order to determine the toxicity effect of silica dioxide (SiO</span><span class="fontstyle0" style="font-size: 7pt;">2</span><span class="fontstyle0">) nano<br />particles on Dunaliella salina green algae in laboratory conditions. SiO</span><span class="fontstyle0" style="font-size: 7pt;">2 </span><span class="fontstyle0">nanoparticle is one of the best<br />full-used nano particles which have application in industries like production of ceramics, plastics, glass,<br />cosmetics, medicine and paper. Dunaliella algae because of having economic value and different<br />biochemical composition is used as complements with natural origin in food and pharmacology<br />industries. For toxicity determination of this material, the experiment was performed according to<br />O.E.C.D standard method. Experiments on Dunaliella were performed for 72 hours with 7 treatments,<br />two controls and three replicates in each treatment and daily counting of cells in each tube. Counting<br />cell algae population was done by microscope on a Thoma counting slide. For data analysis, probit<br />analysis, Excel software and SPSS21 were used. The 72 hours NOEC, EC</span><span class="fontstyle0" style="font-size: 7pt;">90</span><span class="fontstyle0">, EC</span><span class="fontstyle0" style="font-size: 7pt;">50 </span><span class="fontstyle0">and EC</span><span class="fontstyle0" style="font-size: 7pt;">10 </span><span class="fontstyle0">were<br />calculated. The amounts of 72 hours are EC10 =5.37.10</span><span class="fontstyle0" style="font-size: 7pt;">-5 </span><span class="fontstyle0">, EC50 = 0.169 , EC90 = 512.86, NOEC =<br />1.6×10</span><span class="fontstyle0" style="font-size: 7pt;">-2 </span><span class="fontstyle0">mg/l. Cell compression noticeably decreased (P < 0.05) by increasing nanoparticle<br />concentration and silica oxide nanoparticle caused to inhibit growth in Dunaliella species.</span>