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[Determination of 33 inorganic elements in human hair by electricity plate digestion and inductively coupled plasma-mass spectrometry].

OBJECTIVE
To establish the electricity plate digestion and inductively coupled plasma-mass spectrometry (ICP-MS) method for determination of 33 inorganic elements in human hair.


METHODS
Lithium (6Li), Germanium (72Ge), Yttrium (89Y), Indium (115In), and Terbium (159Tb) were used as internal standards. The electric heating board digestion in a mixture of nitric acid and hydrogen peroxide was used as the pre-treatment of the hair. Thirty-three inorganic elements in human hair were analyzed by ICP-MS method.


RESULTS
The detection limit of ICP-MS was 0.0001 microg/g(Th)-10.9 microg/g (Ca) and the limit of quantitation was 0.0005 microg/g (Th)-25 microg/g (Ca). The recovery rate of this method was 86%-113%. The RSD for the intra-day and inter-day were less than 9.2%. The method was not statistically different from microwave digestion method.


CONCLUSION
This method is highly efficient and accurate. It can be used for analysis of 33 inorganic elements in human hair.