Effect of Lead on δ-Aminolevulinic Acid Dehydrase Activity in Red Blood Cells

Abstract

The activity of δ-aminolevulinic acid dehydrase (ALAD) in red blood cells diminishes in lead poisoning. The variation of ALAD activity with the concentration of lead in the blood and the variation of ALAD activity with the concentration of δ-aminolevulinic acid in the urine are both exponential and the correlations inverse. In a study of ALAD in, inter alia, traffic workers, enzymatic activity proved normal. It may, therefore, be assumed that there is almost no risk of lead poisoning by air pollution in the area studied (center of a town with about 250,000 inhabitants). Determination of ALAD activity in erythrocytes is considered a suitable method for demographic studies of exposure to lead. The test is too sensitive for routine follow-up of the degree of lead intoxication in occupationally exposed workers.