Radium was discovered by Marie and Pierre Curie in 1898 in ore mined at the silver mines in Jáchymov, Austria-Hungary (now Czech Republic). It took until 1910 until the element was isolated as a metal by Mme Curie and collaborators. Radium is remarkable in having 34 isotopes (Ra-201 to Ra-234), all radioactive, with half-lives that range from 182 nanoseconds (Ra-216) to 1600 years (Ra-226).
Researchers handling radium concentrates discovered that they often suffered from both surface and deep-skin burns. The realization that the material could damage tissue led to the first applications of the material for the treatment of cancerous ulcers.
The treatment of cancers quickly expanded. In most applications the material was sealed in small, hollow, reusable needles which could be imbedded in the cancer mass. Some applications also used the radon gas, a radium decay product, collected from the metal for treatments.
In addition to medical applications, radium was widely used in self-luminous paints on watches and instrumentation. It was sometimes incorporated into ceramics for water containers. Water from these containers was claimed to have all sorts of invigorating health effects as did bathing in “radium springs” found in several countries. Other uses were as an additive in products such as cosmetics, soap and razor blades, and even “therapeutic” patent medicines like “Radithor” (which proved exceedingly carcinogenic).
Radium is found in uranium-bearing ores (pitchblende) and its low concentration, typically 0.05-0.1 gram per tonne of concentrated uranium ore, make its acquisition in pure form an expensive process. Gram quantities became available in Europe and the USA in the 1920s for prices in the $70,000 to $100,000 per gram range.
Canadian entry into the radium market began in 1929 when Gilbert LaBine, who was born in Westmeath in the Ottawa valley, discovered a deposit of pitchblende on the shores of Great Bear Lake.
Analysis of LaBine’s ore samples by the Mines Branch and Natural Resources laboratory in Ottawa confirmed that the ore was sufficiently rich to be commercially mined. Gilbert LaBine and his brother, Charles, then looked for a place to set up a refinery for their company, Eldorado Gold Mines Limited. They chose the closed premises of the Morrow Seed Company in the economically-depressed town of Port Hope.
The LaBines also needed to find a refining expert to run their refinery. They located that expertise in Marcel Pochon, a man who had worked with radium at the Curie labs in France. Pochon was working in a small radium-extraction plant in Cornwall and immediately agreed to join the Port Hope operation. He arrived in March 1932. By the end of 1933 the refinery had produced 3.012 g of radium.
The main Eldorado competition on world markets was a Belgian-owned company, Union Minière du Haut-Katanga, which obtained its ore from deposits in the Congo. As production from the Congo and the USA increased, the price for radium began to drop; by 1936 it was down to $33000 per gram.
The next decade brought a huge change in the work at Port Hope. The discovery of uranium fission in late 1938 turned the efforts of the refinery to what had been a waste product (and which had been discarded almost willy-nilly around Port Hope), namely, uranium concentrate.
Increasing production of radium elsewhere in the world, the decrease in the ore quality from Port Radium and the post-war emergence of a new cancer-treatment material, cobalt-60, eventually led to the cessation of radium refining at Port Hope. Eldorado Mining and Refining Limited, the crown corporation formed in 1943 from Eldorado Gold Mines Limited, was in fact forced to buy some radium to meet its contract obligations.
In 1949 an arrangement was made between the National Research Council, which operated the National Research Experimental (NRX) nuclear reactor at Chalk River, and Eldorado to market cobalt-60 as one of its product lines. The first Co-60 therapy units were marketed by the Commercial Products Division (later part of AECL), headed by Roy Errington, in 1951.
The radium story does not end here. In recent years the use of radium-223 (half-life 11.4 days) has developed to treat a variety of prostate cancers. This radium isotope is found as a decay product after the irradiation of radium-226 with neutrons.
At the Canadian Nuclear Heritage Museum, the only samples of radium we have are on the face of a small travel alarm clock (the paint no longer glows, but the radium is definitely there). We do, however, have a copy of Robert Bothwell’s excellent book “Eldorado” which follows the history of that company as well as a three-volume set of newspaper clippings and family photographs rescued from the now-demolished, Port Hope home of Marcel Pochon. To visit send an email to info@nuclearheritage.com
Radium needles – photo from “Oak Ridge Museum of Radiation and Radioactivity”
