Oak Ridge’s Graphite Reactor and the Dawn of Nuclear Medicine, 1946

"1946 – Radioisotope Production," an exhibit panel at the X-10 Graphite Reactor. U.S. Department of Energy.

This exhibit panel stands at the X-10 Graphite Reactor, on the secure grounds of Oak Ridge National Laboratory (ORNL) in Tennessee. The reactor can be visited only on guided tours.

A new era of nuclear medicine

In 1946, the Graphite Reactor produced the first radioisotope ever made in a reactor: carbon-14, shipped in a shielded cask to the Barnard Free Skin and Cancer Hospital in St. Louis. With that shipment, the panel says, a new era of nuclear medicine began.

• Many targets at once. A thousand different target materials could be exposed to the reactor's neutrons at the same time, producing radioisotopes — radioactive forms of elements and compounds.
• The first year. The reactor made more than 1,000 shipments of 60 different radioisotopes, chiefly:
• • iodine-131, for treating thyroid cancer;
  • phosphorus-32, for treating leukemia.
• Beyond medicine. Radioisotopes also serve as tracers in academic, industrial and agricultural research, and power satellites, weather stations and space probes.

On the panel

• Photographs show workers in white coveralls at the reactor's experimental face, moving a long, rectangular lead shield on a rolling cart; one holds a wand toward the cart while reading an instrument slung over his shoulder, and another places a cylinder into a thick-walled box with a handle, or works with tongs.
• Another photo shows a worker in a hooded body suit and mask hanging a globe on a metal track through a large circular opening.
• A poster shows a starburst surrounded by a cow, an airplane, a gear and pipes — the many fields radioisotopes reached.
• A portrait shows Alvin Weinberg, ORNL's director from 1955 to 1973, beside his tribute: if a heavenly angel ever asked what the laboratory in the hills of East Tennessee had done to make human life better, he would put the production of radioisotopes for research and medical treatment in the running for first place.

Sources

Based on "Oak Ridge X-10: 1946- Radioisotope Production," Manhattan Project National Historical Park, National Park Service, describing a U.S. Department of Energy exhibit panel; a work of the United States government in the public domain.