AN ASSESSMENT OF SOME BIOMONITORS INDICATIVE OF OCCUPATIONAL EXPOSURETO LEAD

The effectiveness of delta-aminolevulinic acid dehydratase (ALA-D), zi nc protoporphyrin (ZPP), urinary delta-aminolevulinic acid (ALA-U) and metallothionein (MT) as potential biomonitors for health effects of l ead was assessed in an occupationally exposed population. Fifty-one le ad-exposed subjects and 47 nonexposed workers participated in the stud y. While ZPP was not a useful bioindicator for blood lead (BPb) levels below 30 mu g/dl, ALA-D was found to be a more sensitive biomonitor t han ALA-U and ZPP at BPb concentrations between 21 and 30 mu g/dl. In turn, MT would not be a suitable indicator for health effects of lead in occupationally exposed subjects.