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

Reduction of δ-aminolevulinic acid dehydratase (ALA-D) activity in the red blood cells has proved to be the most sensitive test for lead poisoning. The regeneration of ALA-D, after cessation of lead exposure, was studied in 31 men who had worked in a storage battery plant. At the same PbB the ALA-D activity was found to be slightly higher in those whose exposure had terminated than in those with continuing exposure. Regeneration was faster in those men with a shorter exposure to lead and a lower PbB at cessation of exposure.