CLINICAL CHEMISTRY, Vol.18,No. 1.1972 67 Measurementand Distributionof

Simultaneous analyses of human kidney cortex tissues for zinc, cadmium, and mercury were made by neutron activation combined with either radiochemical separation prior to counting or direct germanium detector gamma spectrometry. For some samples from adults and infants, analy-ses were made on successive tissue slices from the outer cortex to the inner medulla. Zinc and cadmium show a concentration gradient, with the highest concentrations at the outer medulla. Mercury was preferentially concentrated deeper in the cortex. All three metals, and especially cad-mium, are found in higher concentrations in adult than in infant kidneys. A mechanism for the rapid increase in renal cadmium is proposed. The heterogeneous renal distribution of the elements indicates that careful sampling is necessary in any comparative study of their occurrence in human kidney tissue. Additional Keyphrases metallothionein in detoxifica-tion #{149}heterogeneity in content, inter- and intrarenal gamma spectrometry #{149}neutron activation #{149}sampling error #{149}age- and environmentally-related effects Studies by Schroeder (17, 18) and others (22, 3), have linked cadmium with hypertension. Rats and rabbits have been made hypertensive by chronic and acute challenges to the animals by various routes-oral, intravenous, and intraperitoneal (19, 20, 22). Evidence in humans that cadmium can cause hypertension is both circumstantial an