fa <span style="font-family:times new roman,serif;"><span style="font-size:12.0pt;">The brine shrimp, <em>Artemia</em> spp., is widely used in ecotoxicological research as a biological index. In the present study, aquatic stability and acute toxic effects of TiO₂, CuO and ZnO nanoparticles (NPs) on <em>Artemia franciscana</em> were investigated<em>. </em>Acute exposure was conducted in sea water with different concentrations of selected nanoparticles at 24h, 48h, 72h and 96h. The mortality rate of <em>A. francisca</em> increased significantly with increasing concentrations and duration of exposure of all NPs. The toxicity pattern of metal oxides to <em>A. francisscana</em> was as follows: CuO>TiO₂>ZnO. Our results point to the fact that both TiO₂ and ZnO NPs exhibited moderate toxicity to <em>Artemia</em> larvae in 24h as compared with CuO, regardless of their size and concentrations.</span></span> Acute toxicity, Artemia franciscana, Titanium dioxide, Copper oxide, Zinc oxide 1287 1296 http://jifro.ir/browse.php?a_code=A-10-1079-1&slc_lang=fa&sid=1 R. Khoshnood 100319475328460023935 100319475328460023935 No N. Jaafarzadeh Jaafarzadeh-n@ajums.ac.ir 100319475328460023936 100319475328460023936 Yes Sh. Jamili 100319475328460023937 100319475328460023937 No P. Farshchi 100319475328460023938 100319475328460023938 No L. Taghavi 100319475328460023939 100319475328460023939 No