Screening for chronic lead poisoning in lead factory workers

One hundred and forty-nine lead factory workers comprising of 46 fume exposed, 78 handling lead materials and 25 controls were screened for chronic lead poisoning. Blood lead level was determined by atomic absorption spectrometery and urinary ALA by ion-exchange chromatography. Fume exposed workers had significantly higher (P < 0.01) blood lead (median 61.20 micrograms/dl, range 21.20-171.10 micrograms/dl) and urinary ALA levels (median 4.10 mg/l, range 01.0-22.9 mg/l) than workers handling lead materials and controls. Urinary ALA was found to be a more sensitive and specific test for lead poisoning than estimation of blood lead levels.