Incidence of subclinical lead (Pb) exposure in cattle of an industrial area in Greece.

The incidence of subclinical lead (Pb) poisoning was investigated in the cattle population of an industrial area in northern Greece. The cattle were divided into two groups with respect to their alleged exposure to Pb, which was assayed by determining whole blood and hair Pb concentration and erythrocyte delta-aminolevulinic acid dehydratase (ALA-D) activity. The cows which were located closer to potential contamination sources were found to have higher (P < 0.05) blood and hair Pb content, whereas no significant differences were noted in ALA-D activity. Hair Pb increased significantly (P < 0.05) with age, an observation which should lead to further, more extensive research, in order to evaluate the possibility of using hair as indicator of chronic Pb intake.