Studies in lead poisoning. Oral therapy with penicillamine: relationship between lead in blood and other laboratory tests.

Fifteen workers with lead poisoning of varying degrees were treated with penicillamine given by mouth. The effect on symptoms and pathological laboratory values was satisfactory, side effects were generally mild and the drug is considered to be a good alternative to Ca-EDTA, which must be given intravenously. Previous studies on the reliability of different laboratory tests in evaluating the degree of lead poisoning and the effect of the therapy were extended with special respect to the lead levels in blood. The correlations between lead in blood and lead in urine, coproporphyrins in urine and lead excreted during treatment were of the same order as those found between delta-aminolaevulic acid (ALA) in urin and the same parameters. As could be expected, the correlation between the initial values of lead in blood and ALA in urine was very strong (p<0·001). It also persisted during treatment. It is concluded that penicillamine is efficient and useful in the treatment of lead poisoning. Determinations of lead in blood and ALA in urine are equivalent as expressions of lead poisoning, provided that the lead level in blood is not temporarily raised because of an acute exposure.