Semi-automatic determination of lead in whole blood.

The procedure developed by Browett and Moss (1964) for the semi-automatic determination of the lead content of urine has been adapted for the determination of lead in blood. Determinations are normally carried out in duplicate on 2.0 ml. samples of whole blood and the minimum sample size is 0.5 ml. The organic substances present in blood are destroyed by a manual wet-oxidation procedure and the lead is determined colorimetrically as lead dithizonate using a Technicon AutoAnalyzer. The lower limit of detection, expressed as three times the standard deviation of the blank value, is 5 mug. Pb/100 ml. blood. The standard deviation of the method in the upper range of normal blood lead level of 30 mug. Pb/100 ml. blood (Moncrieff, Koumides, Clayton, Patrick, Renwick, and Roberts, 1964), is +/- 3 mug. Pb/100 ml. blood. Ten samples per hour may be estimated in duplicate.