Background and Objective: With the industrialization of nanotechnology and increase in application of nanoparticles in modern technology, carrying out research on nanoparticles and their effects on health is necessary. So, this study was aimed to assess acute toxicity of molybdenum nanoparticles on serum biochemical function of kidney in rat.

Materials and Methods: In this experimental study, 24 male rats were randomly divided into four groups of six: a control group and tree treatment groups. The control group received 1 ml distilled water and the treatment groups received intraperitoneal injection of 5, 10 and 15 mg/kg of molybdenum nanoparticles of 10 nm daily for 28 days. After the last dose, blood samples were taken from all groups and levels of Blood Urea Nitrogen (BUN), creatinine, total protein and albumin were measured and then the groups were compared.

Results: The serum levels of BUN and creatinine in the group receiving 15 mg/kg dose decreased significantly compared to the control group (P<0.05). The serum albumin level in the groups receiving 10 and 15 mg/kg doses showed significant decrease compared to the control group (P<0.05). The serum total protein level in the groups receiving 5, 10 and 15 mg/kg doses showed significant decrease compared to the control group (P<0.05).

Conclusion: The results of this study showed that molybdenum nanoparticles of 10 nm at these concentrations decrease creatinine and BUN levels of serum.