ATOMIC-ABSORPTION SPECTROMETRIC DETERMINATION OF CADMIUM AND LEAD IN HUMAN AND ARTIFICIAL TEETH BY DIRECT ATOMIZATION TECHNIQUE

A method of graphite furnace atomic absorption spectrometry (GFAAS) with a direct atomization technique has been developed for the determination of trace amounts of Cd and Pb in human teeth and artificial teeth. The samples were ground to a particle size of less than 10 mu m and mixed with the same amount of graphite powder. One-half to 2 mg of mixed sample was weighed in a tared graphite cup and atomized in a cup-type graphite furnace according to the heating program that was established. Absorbances were determined by integration of the spectral lines in the absorbance vs time spectrum. Calibration was affected using aqueous standard solutions. The results for six human tooth samples and two artificial tooth samples were in good agreement with the values obtained by GFAAS for dissolved samples. The relative standard deviations were 3.1-12% (n = 10) for Cd (19-95 ng g(-3)) and 0.9-8.1% (n = 10) for Pb (1.43-6.32 mu g g(-3)). The determination limits corresponding to twice the standard deviation (sigma, n = 10) for blank measurements were 13 pg for Cd and 53 pg for Pb. (C) 1995 Academic Press, Inc.