RELATIONSHIP BETWEEN ALPHA-AMINOLEVULINIC ACID DEHYDRATASE ACTIVITY, FREE ERYTHROCYTE PROTOPORPHYRIN CONCENTRATION AND BLOOD LEAD IN CALVESFROM LEAD CONTAMINATED FARM

In order to investigate useful indicators of lead contamination, 108 J apanese Black calves from a lead-contaminated farm were used. The lead concentrations in blood (Pb-B), delta-aminolevulinic acid dehydratase (ALA-D) activities, and free erythrocyte protoporphyrin (FEP) concent rations were examined. A significant negative correlation was obtained between Pb-B concentrations and ALA-D activities (r=-0.621, p<0.01). A significant positive correlation was obtained between Pb-B concentra tions and FEP concentrations (r=0.850, p<0.01). The calves were divide d by Pb-B concentrations (mug/100ml) into 5 groups (A= less-than-or-eq ual-to 30, 8=31 approximately 90, C=91 approximately 150, D=151 approx imately 210, E= greater-than-or-equal-to 211) to observe the relation of ALA-D activities, FEP concentrations and Pb-B concentrations. A sig nificant negative correlation was obtained between Pb-B concentrations and ALA-D activities in group B (r=-0.706, P<0.05). A significant pos itive correlation was obtained between Pb-B concentrations and FEP con centrations in groups A, B and D (A=r=0.496, p<0.01; B=r=0.686, p<0.01 ; D=r=0.529, p<0.05). These results indicate that FEP concentrations w ere good indicators of lead contamination.