On the Presence of Aluminum in Plant and Animal Matter.

In an article entitled, “A Study of the Possible Role of Aluminum Compounds in Animal and Plant Physiology,” by McCollum, Rask, and Becker,’ these authors arrived at the conclusion that, “Aluminum is not a constituent of either plant or animal matter.” Since this conclusion is so contrary to what has been found by all previous investigators, we have performed the following experiments in order to ascertain whether plant and animal matter does not contain aluminum in quantities sufficient to be detected by means of the spectroscope. The instrument used was a Kriiss quartz prism spectrograph and the materials examined were whole hen’s egg exclusive of shell, potato, carrot, English walnut meat, peach pit, apricot pit, pop-corn, Lima bean, navy bean, lupin bean, peanut kernel, lean beef, beef tendon, and human cancerous tissue excised by the surgeon from the breast of a woman of middle age. In all of these cases aluminum was found to be present in quite sufficient amounts to be detected with certainty with the spectroscope. Extreme precautions were used to guard against all possible contamination of the materials while they were being cleansed, ashed, and finally tested spectroscopically. Adhering dirt was removed by careful washing with distilled water. The materials were then dried and ashed in platinum dishes at a dull red heat. No reagents whatever were used, and so the only possible source of contamination of the material with aluminum was through the atmosphere. Consequently, while the work was in progress, the air of the laboratory was kept as dust-free as possible. The