STUDIES OF COPROPORPHYRIN. I. THE PER DIEM EXCRETION AND ISOMER DISTRIBUTION OF COPROPORPHYRIN IN NORMAL HUMAN URINE 1

Abstract

Total urinary coproporphyrin excretion was studied in 53 normal adults in the Minneapolis area. Values ranged from 17 to 99[mu]g. per day, with an avg. value of 55[mu]g. per day. Of this total, 48-92% consisted of the type I isomer (avg. 76%), the remainder being coproporphyrin type III. Control individuals in Chicago during the war yrs. were found to excrete chiefly the type III isomer. However, studies in 1940 in 11 normal individuals from the same area showed a reversal in all to a preponderant coproporphyrin I excretion, similar to that found in the Minneapolis group. It is suggested that the introduction of filtration and other water-purification steps during the interval between the 2 studies may account for this reversal.