QUANTITATIVE URINARY COPROPORPHYRIN EXCRETION AND ITS RELATION TO EDATHAMIL CALCIUM DISODIUM ADMINISTRATION IN CHILDREN WITH ACUTE LEAD INTOXICATION 12

Abstract
A positive exponential correlation was found in childhood lead poisoning between the urinary lead output during the first day following the parenteral administration of edathamil calcium disodium and the daily urinary coproporphyrin output just prior to the administration of this chelating agent. A similar correlation was found between the simultaneous daily urinary outputs of coproporphyrin and lead during drug administration. It was postulated that the urinary coproporphyrin output is related to that fraction of lead in the tissues which is available for chelation and urinary excretion under the influence of edathamil calcium disodium. The urinary coproporphyrin excretion may provide a sensitive biochemical index of "metabolically active" and presumably toxic lead in the soft tissues.