RESUMO
An atomic-absorption spectrophotometric method is used for the determination of trace amounts of lead by using the solvent extraction. The extraction of lead fluorescence with tri-n-butyl phosphate [TBP] and consequent atomic-absorption determination was found to decrease as the pyridine or cadmium ion concentration was increased, but it increased with the concentration of potassium iodide. Toluene, benzene and methyl ethyl ketone diluents increased the sensitivity of the method. Beer's law is obeyed in the concentration range 0.2 - 25 ppm of lead. Six replicate determinations on a sample containing 20 ppm of lead gave a mean absorbance of 0.85 with a standard deviation of 0.66%. The method was successfully applied to the determination of lead in blood serum