ALA D and exposure to lead in a crystal glass factory [ALA-deidratasi eritrocitaria ed esposizione al piombo negli operai di una cristalleria]

In order to establish the risk of lead exposure among the workers of a crystal factory, determinations of airborne lead in the working environment were made simultaneously, laboratory tests on the workers were carried out, including measurement of erythrocyte delta amino levulinic acid dehydratase (ALAD) activity, of urinary delta amino levulinic acid, and haemoglobin. The environmental measurements revealed a moderate lead pollution, which was more marked in some work places and during some stages of the production process. Of the laboratory data obtained from the workers, the determination of erythrocyte ALAD activity appeared particularly useful, since it was subject to a statistically significant reduction compared with the data obtained from a control group living in the same area, not occupationally exposed to lead. No statistically significant differences were however found between the values of urinary ALA and haemoglobin in the crystal workers and the control group. This confirms the usefulness of determining ALAD in preventive and occupational medicine in order to single out subjects exposed to lead absorption, even in moderate quantities and such as not to influence other currently used biological indices.