Abstract: Objective: To explore the toxicity of sodium selenite. Methods: Wistar rats were used to explore acute toxicity and accumulative toxicity of sodium selenite by the modified Karber method and the dose-increasing method, respectively. In addition, rats administered with sodium selenite at doses of 1/20 LD50, 1/10 LD50 and 1/5 LD50 for 30 consecutive days were used to explore its sub-acute toxicity. The growth status, histopathological change and blood biochemical indices of rats were determined. Results: The LD50 of sodium selenite was 11.75 mg/kg and the accumulative coefficient was 3.3, which revealed a moderate capacity of accumulative toxicity for rats. However, the growth of rats was inhibited when the concentration of sodium selenite was up to 0.588 mg/kg. The major organs including heart, liver, spleen, lung and kidney were damaged to different extents and blood biochemical indices were affected by sodium selenite at high concentrations. Conclusion: Sodium selenite is a material with high toxicity, which can cause acute, accumulative and sub-acute toxicity to rats.

Key words: sodium selenite, rats, acute toxicity, accumulative toxicity, sub-acute toxicity