ZINC AMINOLEVULINIC ACID DEHYDRATASE REACTIVATION INDEX AS A TOOL FORDIAGNOSIS OF LEAD-EXPOSURE

The correlation between blood lead level (BLL), delta-aminolevulinate dehydratase (ALA-D) activity, and other common biochemical parameters used to assess a plumbism diagnosis have been carefully analyzed, with the aim of correctly interpreting the data handled in the laboratory. No correlation was observed between BLL and free erythrocyte porphyri ns. In the case of ALA-D or Zn-reactivated ALA-D despite the direct co rrelation with BLL, the curve follows a potential or a logarithmic lin e, which is not the best to calculate BLL. The so-called Zn-ALA-D-reac tivation index (iZn) has been defined as the ratio between the activit y of Zn-reactivated ALA-D and the activity of ALA-D. The plot of BLL a gainst the iZn revealed a very good linear relationship which allows a n estimate of BLL with reasonable accuracy within a very wide range. ( C) 1995 Academic Press, Inc.