Rutherford's Radiations

Radiation penetrated popular culture early and quickly. Entrepreneurs used radium in products like toothpaste and shoe polish in order to tap into the public's consciousness of these experiments and discoveries, but also preying on their respect and awe of science. This practice persists today, but with the sale of magnets that claim to align your "fields" or draw out "toxins", or the self-help gurus who misrepresent quantum mechanics to convince eager adherents of the mystic qualities of the Universe.

In comic books, radiation also turned regular people into superheroes. After the first atomic, further experiments with uranium-235 turned Adam Mann into Atomic-Man, the first in the “Atomic Age” of superheroes. Superman fought Atom Man (an alias of supervillain Lex Luthor), who created synthetic kryptonite out of plutonium and uranium in order to defeat Superman. Bruce Banner was exposed to gamma radiation and became uncontrollable and green Hulk. The Fantastic Four got their powers from cosmic rays in space. Chen Lu was exposed to radiation in order to find a way to defeat the god Thor and gained the power to manipulate microwave radiation, taking on the unlikely moniker of Radiation Man. More recently, Dr. ManThese characters served as metaphor for the great power of radiation in the aftermath of the destruction caused by the atomic bomb. They showed how the might of nuclear power could be used for good (Fantastic Four, Atomic-Man) or evil (Radiation Man, Lex Luthor). Other radiation-related comics were educational, like the issue of Blondie: Dagwood Splits the Atom. The ramifications of radiation’s presence in the popular consciousness is also explored in films such as Godzilla, where the titular monster was released thanks to the tremors accompanying the atomic bombs dropped on Japan and Them!, which featured giant ants that were mutated by radiation; as well as in video games like the Fallout series and the S.T.A.L.K.E.R: Shadow of Chernobyl games. There is even a radiation themed Japanese pop group called Hot☆Spots, whose aim was to make the idea of radiation less frightening in the wake of the Fukushima disaster.

The first modern particle accelerators really begin with the cathode ray tubes that were used by Rutherford and Thomson in their early experiments on the electron. When the electrons within the tube are exposed to an electric field, they accelerate and leave the tube with more energy. This is the fundamental use of a particle accelerator: accelerating particles. These methods sufficed, alpha-particles taking the place of electrons for many years. In 1927, Rutherford gave an address to the Royal Society urging scientists to look into accelerator technology, stating:

The advance of science depends to a large extent on the development of new technical methods and their application…From the purely scientific point of view interest is mainly centered on the application of these high [industrial] potentials to vacuum tubes in order to obtain a copious supply of high-speed electrons and high-speed atoms...This would open up an extraordinarily interesting field of investigation which could not fail to give us information of great value, not only in the constitution of atomic nuclei but in many other directions. (Cited in Reeves 120)

Freeman Dyson would later say, writing in 2005:

New tools were needed if nuclear physics were to move ahead…The most promising new tool would be a particle accelerator...Artificially accelerated particles would be better than natural particles in three ways: they could be produced in greater quantities, they could have higher energies and they would allow experiments to be designed more flexibly...The switch from natural sources to accelerators would start a new era in the history of science. (Cited in Reeves 121)

Once Cockcroft and Walton developed their accelerator, which they used to successfully accomplish the first splitting of atom, intricate, high-voltage machines became ubiquitous in the laboratory.

At the same time, Ernest Lawrence at University of California Berkeley was developing a cyclotron with his graduate student, Stanley M. Livingston. Their machine managed to produce 80,000 electron-volts of energy, but it was not enough to disintegrate a nucleus. Once Lawrence heard that Cockcroft and Walton succeeded in disintegrating, he continued redesigning his experiment in order to catch up with the Cavendish researchers. Five months later, he succeeded in observing the disintegration of lithium atoms.

Nuclear Medicine

The world of medicine has also benefitted immensely from Rutherford's early work on radiation. Nuclear medicine began in the early 20th century, as a direct consequence of some of Von Hevesy’s early research in radioactive materials. To some, Von Hevesy is the father of nuclear medicine. In 1923, Von Hevesy used a naturally occurring isotope lead-212 that had a 10.6 hour half-life. He was the first to use radioisotopes as tracers, observing how a bean plant absorbed the lead solution. Using an electroscope, he examined how much radioactivity was present in the roots, stem, leaves and fruit of the plant. Von Hevesy followed these experiments, with the assistance of Christiansen and Lomholt, tests done in rabbits. The scientists used bismuth-210 to study the circulation of the bismuth throughout the rabbits' bodies. Later, in 1934, Von Hevesy, apparently remembering a discussion he had with Moseley while they were both in Manchester conducted an experiment with tea:

Shortly after the first application of radioactive isotopes as indicators, in the spring of 1913, the late H. J. G. Moseley and the present writer discussed the prospect opened by the introduction of this method, when indulging in a cup of tea at the Manchester Physics Laboratory. The latter then expressed the wish that an indicator might be found which would allow us to determine the fate of the individual water molecules contained in the cup of tea consumed. (Hevesy 1966: Adventures in Radioisotope Research 536)

With the discovery of heavy water by Urey in 1931, von Hevesy was finally capable of realizing this wish. He and E. Hofer consumed deuterium diluted with tea, and found that traces of the radioactive material stayed inside them for 13 ± 5 days. (From what I can tell, this is the first example of humans ingesting radiation as a tracer, though Hevesy did use tracers back in 1913 at Manchester to prove that his landlady was not giving him fresh meat).

In the 1950s, Hal Anger developed a scintillation camera which imaged the gamma radiation emitted by radioisotopes. This allowed doctors to use tracers to construct complex images of organs and systems in the body. The Anger Camera (also called, less frighteningly, the Gamma Camera) led the way for more complex imaging techniques, such as positron emission tomography. Patients would ingest or are injected with radionuclides, with become absorbed into the body's tissue. From there, it gives off radiation in the form of positive beta particles (positrons and neutrinos, as opposed to regular beta’s electron and anti-neutrino). The positron interacts with an electron and forms a pair of high-frequency protons, or gamma rays. The camera sees these protons coming out, and can reconstruct an image of the patient’s insides from the information. This is one of the most direct examples of Rutherford's work living on in medicine, and Hevesy won the Nobel in Chemistry in 1943 to his contributions to this work.

Imaging and diagnostics is not the only utility for nuclear medicine, it is also invaluable as a cancer therapy. At the Berkeley Laboratory, John Lawrence and his brother Ernest began exposing rats to the beryllium target of the lab’s cyclotron and bombarded them with neutrons to see how the exposure compared to x-rays. They found that the neutrons affected the ionization in the tissue of the rats twice as much as the x-rays did. A similar experiment performed by Raymond E. Zirkle using wheat seeds found that neutron exposure was twenty times as damaging. Though this makes it sound like neutrons are extraordinarily more dangerous than x-rays, this is not necessarily the case. In an experiment that sought to remove tumors from mice, it was found that the amount of x-ray radiation it took to kill a tumor would also kill the mouse. This was not the case for neutron therapy.

"The newly [!] discovered neutron ray...seems to provide a means of overcoming the handicap which now limits the effectiveness of the x ray in the treatment of cancer. It appears that it can be used to increase the destruction of cancerous tissue without increasing the damage to the normal tissue" (Robert Gordon Sproul cited in Helibron & Seidel, 391)

The first human patients were exposed to neutron beams from the cyclotron in 1938. The results were encouraging, with Lawrence saying:

It gives me great pleasure to report an event of historic interest...I personally believe, and my views are shared by my medical colleagues, that this will be the beginning of a new method of cancer therapy which in a few years will be as widespread as that of x rays and radium (Cited in Helibron & Seidel, 393)

The first full treatment therapy began in January, 1940. Using the new 60-inch cyclotron dubbed the “Crocker cracker”, Lawrence and his team succeeded in disappearing several tumors. The therapy was administered until 1943, when Stone performed an evaluation of the program, and found that only 18 of the 250 people treated since 1939 had survived. Though all but one had been diagnosed as incurable, those that survived mentioned that they were suffering from certain side effects that may not have had otherwise, using x ray treatments. Stone judged that Lawrence had been overexposing his patients, and the field of neutron therapy was shut down for nearly twenty years.

In the 1970s, after many years of experimentation with new dosages, the Hammersmith Hospital in London began treating cancer patients with 7.5 MeV neutrons. The practice that resulted in tumors regressing 70% of the time.

"Hundreds of mice and hundreds of tumors are being killed by neutron rays."
Helibron, Seidel, 390