[Remarks on the use of shortened procedures in evaluating EDTA-induced urinary lead excretion]

Urinary lead excretion following EDTA administration was studied in 47 both normal and lead intoxicated subjects, mainly monitoring the rate of excretion through sequential urine samples. Urinary lead excretion patterns proved to be quite different in the examined subjects: in particular, great differences were noted in the onset of lead excretion increase. The six-hr lead excretion resulted to be 60,7% of the total 24-hr excretion, with, however, a very wide range (42% to 83%). Urine flow didn't appear to influence the rhythm of urinary lead excretion. There is sufficient evidence to justify the conclusion that evaluation of EDTA-induced urinary lead excretion on the basis of the first-six-hr results cannot be assumed as a reliable procedure, unless it is used for rough diagnostic screening purposes.