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Silver nanoparticles (AgNPs) are widely used in consumer products mainly due to their antimicrobial action. The rapid increase in the use of nanoparticles has driven more attention to their possible ecotoxicological effects. In this study: first, acute effects of colloidal AgNPs during embryonic stage of Persian sturgeon and Starry sturgeon were investigated and then in Starry sturgeon, their short-term effects during early life stages (before active feeding commences) were analyzed. Based on the obtained results from the acute toxicity tests, AgNPs induced a dose-dependent toxicity in both species during early life stages. The short-term toxicity test was performed using 0, 0.025, 0.05 and 0.1 mg/l of colloidal AgNPs. Silver accumulation in larvae exposed to 0.1 mg/l AgNPs was recorded significantly higher than the control treatment (P<0.05). However, the obtained survival rate data did not indicate any significant differences among treatments.