GF-AAS Determination of Lead and Cadmium in Food Additives with Microwave Assisted Sample Digestion

A method of GF-AAS for the determination of Pb and Cd in food additives was proposed.The sample was treated by microwave digestion with HNO3 and H2O2.Ammonium dihydrogen phosphate was used as a matrix modifier.The ashing and the atomization temperature for Pb was 600 ℃ and 2 100 ℃ and for Cd was 400 ℃ and 1 800 ℃ respectively.Under the optimum conditions,values of RSD′s (n=6) was found in the range of 2.8%-6.5% for Pb and 2.4%-5.3% for Cd,with recovery in the range of 94%-102% for Pb and 96%-103% for Cd.