Determination of Lead and Cadmium in Human Hair by GFAAS with Microwave Digested Samples

Pb and Cd in human hair were determined by graphite furnace atomic absorption spectrometry. The samples were digested by microwave with (NH₄)₂SO₄ plus KH₂PO₄ as the modifier to eliminate the matrix interference. The type of digestant, digesting pressure and instrument parameter were studied. The method is simple and accurate. The average recoveries were 101.8% and 107.1% for Pb and Cd, respectively, and the relative standard deviations were 5.14% and 6.80%, and the detection limits were 9.53 ng/mL and 0.78 ng/mL.