Direct atomic absorption determination of cadmium and lead in strongly interfering matrices by double vaporization with a two-step electrothermal atomizer

Thermal pretreatment of a sample using double vaporization in a two-step atomizer with a purged vaporizer makes possible the direct analysis of samples with strongly interfering matrices including solids. A porous-graphite capsule or a filter inserted into the vaporizer is used for solid sample analysis. The technique was used for the direct determination of Cd and Pb in human urine, potatoes, wheat, bovine liver, milk powder, grass–cereal mixtures, caprolactam, bituminous-shale and polyvinyl chloride plastic without chemical modification or any other sample pretreatment.