ABSTRACT
OBJECTIVE:To establish a method for the contents determination of 5 heavy metals in Ershiwuwei shanhu pills, and to investigate the contents of heavy metals in Ershiwuwei shanhu pills produced by 5 manufacturers from different districts of Tibet. METHODS:Ershiwuwei shanhu pills were digested by HNO3-HClO4(4:1,V/V).The contents of 3 heavy metals as Cu,Pb, Cd in samples were measured by flame atomic absorption spectrometry(FAAS). The contents of 2 heavy metals as As,Hg in samples were measured by hydride generation atomic absorption spectrometry(HG-AAS). RESULTS:5 kinds of heavy metals have good linear relationship in the corresponding mass concentration range(all r≥0.999 1). The limits of detection of Cu,Pb, Cd were 0.001 6,0.041 2,0.036 3 mg/L,and the limits of quantitation were 0.005 3,0.137 3,0.121 0 mg/L;the limits of detection of As,Hg were 0.325 7,0.692 3 μg/L,and the limits of quantitation were 1.085 7,2.307 7 μg/L. RSDs of precision tests were ≤5.54%(n=6);RSDs of stability tests were all≤3.79%;RSDs of reproducibility tests were ≤3.72%. The average recovery rates were 91.34%-110.11%(RSDs were 0.66%-6.80%,n=6). Results of contents determination showed that the contents of Cu in samples from 5 manufacturers were not out of limits,but the contents of Cd and Hg were all out of limits; the contents of Pb in samples from 4 manufacturers were out of limits,and the contents of As in samples from 2 manufacturers were out of limits. CONCLUSIONS:The established method has good accuracy,sensitivity,stability and reproducibility,and it is suitable for contents determination of 5 heavy metals in Ershiwuwei shanhu pills. To some extent,there is a problem of excessive heavy metals in samples from 5 manufacturers.