Nano-Se acute toxicity and accumulative tests for Kunming mice

Acute toxicity test and accumulative test were conducted to assess potential toxicity of nano-Se particles in sizes of 100 nm.Improved Korbor method was adopted to conduct acute toxicity test,dosage gradients of nano-Se preparation with 0.25 percent carboxymethyl cellulose solution were determined according to lethal dose and no mortality dose of nano-Se preparation which were concluded from pre-experiment.Dosage gradients of nano-Se preparation were orally administered 482.04,303.94,191.64,120.83,76.19 mg se/kg bw.Median lethal does(LD50) and pathological transform of acute poisoning mice were determined by mortality of mice in different groups during 21 days.One fifth of LD50 as dosage administered orally was adopted for 25 days in accumulative test.It could be concluded from acute toxicity that LD50 for nano-Se was 303.94 mg/kg BW(276.75～391.66 mg/kg bw) and toxicity of nano-Se lethal dosage could resulted in death of mice within 48h,it took 5 days to recover from acute toxicity at non lethal dosage.Results of accumulative test showed that K5 which was a slight accumulation.