A Spectrochemical Study of the Normal Ranges of Concentration of Certain Trace Metals in Biological Materials

Abstract

A quantitative spectrographic method of high sensitivity and precision has been employed for the simultaneous determination of lead, manganese, tin, aluminum, copper and silver in normal biological material. Lead, manganese, copper and aluminum were present in all materials examined; tin was present in about 80% and silver in 10 to 20% of the samples. The mean concentrations of these metals in a liter of normal urine has been found to be below 0.01 for manganese and 0.078, 0.034, 0.027, 0.011, and 0.00 mg. respectively for aluminum, copper, lead, tin and silver. The mean concentrations of the metals in 100 gm. of normal whole blood are 0.114, 0.025, 0.015, 0.013, 0.012, and 0.00+mg. respectively for copper, lead, manganese, aluminum, tin and silver. Practically all of the manganese, lead and tin is contained in the formed elements of the blood; aluminum is found almost entirely in the plasma, while copper is almost evenly divided between the two, the formed elements usually containing a slightly higher concentration. The concentrations of these metals in consecutive daily or weekly samples of urine and blood from the same individual are not constant but vary from sample to sample. The daily output of this group of metals in the feces is practically equivalent to their daily intake in the diet. The wide distribution of lead is indicated by data obtained on a large number of natural materials.