The Acute Toxicity of SiO2 and Fe3O4 Nano-particles on Daphnia magna

Abstract

SiO2 nano-particles are applied in different industries such as ceramic producing, glass making, cosmetic products, medicines, magnetic mixtures, heat and electric insulators and glazing currently. Also, nano particles of SiO2 can be utilized to increase the strength and stability of industrial coverings. Fe3O4 nano-particles enjoy pretty special and unique features compared to bulk Fe3O4 in terms of ultra-magnetic features, size and quantum feature. These nano-particles that are considered as one of the most important elements of iron-based mixtures, soft magnetic materials, record-player sets, colorful materials, magnetic suspended materials, magnetic vibrant recording in tissues recuperation and molecules diagnosis are highly used in pharmacy and biotechnology. With the development and progress of nano technology and increasing use of engineered nano-particles and besides all the benefits of nano particles; potential pollution of nano-particles should be considered that may occur after their transportation and entery into water environments. The aim of this research is to investigate the toxicity effect of SiO2 and Fe3O4 nano-particles on Daphnia magna that is regarded as a kind of hard zooplankton in fresh water and is as main aquatic ecosystem food chain after phytoplankton groups. In this test, OECD (Organization for Economic Cooperation and Development) method (202) was used and the toxicity effect of Fe3O4 and SiO2 nano-particles on Daphnia magna during 96 h was investigated. The daphnia had exposure to 6-treatments of nano silica solution, 5 treatments of nano iron oxide with three replications for each in comparison with control group. LC50 of silica and iron oxide nano particles were analyzed by probit data analysis method for the determination of Daphnia magna proportion in each solution following 96 h and respectively the following amounts of 1.73 and 654.65 mg/l were observed. The results of the study showed the lower rate of toxic effect in iron oxide nanoparticles compared to nano silica in Daphnia magna.