A method for the determination of lead in blood by atomic-absorption spectrophotometry

Abstract
A method for the determination of trace amounts of lead in blood is described. The organic material in the blood is oxidised by dry ashing at 500° C and a solution of the ash in dilute hydrochloric acid prepared. The lead in the ash solution is determined by atomic absorption at 217 nm in an air-propane flame after isolation by a double-extraction procedure with dithizone and ammonium tetramethylenedithiocarbamate as complexing agents. Recovery tests are carried out and the lead content of the blood of workers from a lead mine, determined by this method, is compared with results obtained by using the mixed colour method of the Analytical Methods Committee. Comparative tests with wet-oxidation and dry-ashing techniques are made on samples of blood to which known amounts of lead have been added. The interference caused by bismuth is also investigated.