Radium in Medical Use in the United States

Abstract

RADIO-ACTIVITY, the property of radium that led to its isolation more than thirty years ago, is the characteristic that makes it of value in the treatment of disease. Tyler2 gives the following brief history of the investigation: “The way to the discovery of radium was opened in 1895 by Roentgen, who found that the glow from a Crookes tube contained penetrating rays, which he called x-rays. Prof. Henri Becquerel, while investigating the effect of various phosphorescent substances, found that uranium salts produced photographic impressions even when enveloped with opaque substances. To Marie Sklodouska, a young Polish student, who later became Madame Curie, Prof. Becquerel delegated the task of learning how and why uranium possessed power to emit these peculiar rays, which he had proved to be electrical in character. Madame Curie, examining by electrical methods the radio-activity of a large number of minerals containing uranium and thorium, discovered that some specimens of pitchblende had about four times the activity of the metal uranium; that chalcolite, the crystallized phosphate of copper and uranium, was twice as active as uranium; that autunite, a phosphate of calcium and uranium, was quite as active as the same weight of pure uranium. In order to check these discoveries, she prepared chalcolite artificially, starting with pure products, but found that this artificial chalcolite had only the activity represented by its composition, or, roughly, 40 per cent of the activity of uranium. This led to the conclusion that there was some element or substance in the residue from uranium minerals that possesses a high degree of activity. After an exhaustive chemical investigation of pitchblende from Joachimsthal, she found that this mineral contained not only uranium but also another radio-active substance, to which she gave the name of polonium, in honor of her native land. Later in 1898, Monsieur and Madame Curie found still another element, which, when brought to a state of concentration, was several million times as active as uranium, and to this was given the name of radium. Debierne afterwards found a fifth radio-active substance, actinium, and in 1906 Boltwood isolated the metal ionium. Strictly pure radium chloride was first produced in 1902.” The first radium was produced commercially from the uranium residues obtained from the mines of Joachimsthal, Bohemia. Tyler calls to attention that, as the ores were a government monopoly, search was begun at once for sources in other parts of the world. As a result, radium-containing ores have been found in about ten countries. The interest of the Bureau of Mines in the efficient recovery of radium extends back to about 1912. Under an agreement with the National Radium Institute3 the Bureau built and, in June, 1914, began the operation of a radium-recovery plant at Denver, Colorado. By the time the work ceased in January, 1917, 8.5 grams of radium had been produced.