title: Long-term observation of biochemical effects of lead in human experiments.
abstract: In extension of two previous series of experiments, the results of which have been partially reported (1), further long-term tests were performed with daily oral doses of 5 mg Pb++ in 2 subjects. Lead in whole blood, free protoporphyrin 9 (III) and 5-aminolevulinate dehydratase activity in erythrocytes, hemoglobin, and urinary 5-aminolevulinic acid and coproporphyrin III excretion values were measured. From experiences with 8 human experiments, three compartmental phases of early detectable lead effect were postulated: 1. an "erythrocytic" reaction of 5-aminolevulinate dehydratase activity, 2. "hepatic" reactions of 5-aminolevulinic acid and coproporphyrin, and 3. an "erythropoietic" reaction of protoporphyrin.
mesh_terms: D000328:Adult; D000622:Aminolevulinic Acid / Q000652:urine; D003306:Coproporphyrins / Q000652:urine; D004912:Erythrocytes / Q000378:metabolism; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007854:Lead / Q000097:blood; D007855:Lead Poisoning / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D000623:Porphobilinogen Synthase / Q000097:blood; D011524:Protoporphyrins / Q000097:blood; D013997:Time Factors
chemical_list: D003306:Coproporphyrins; D006454:Hemoglobins; D011524:Protoporphyrins; D007854:Lead; D000622:Aminolevulinic Acid; D000623:Porphobilinogen Synthase