Radiation Protection Stories
Playlist created by IRSN | 12 videos |
Film produced for the exhibition "Did you say Radiation protection?" Pavillon des Sciences - Montbéliard. October 15, 2007 – April 27, 2008 A co-production of: Communauté d'Agglomération du Pays de Montbéliard (CAPM) Institut de Radioprotection et de Sûreté Nucléaire (IRSN) Pavillon des Sciences - CCSTI de Franche-Comté
On December 28, 1895, the German physicist Wilhelm Conrad Röntgen announced he had discovered rays which he called X. With these rays, we can see inside objects, and when the hand is interposed, it is the bones that appear! For the public, these rays are a source of entertainment. For doctors, they offer a revolutionary technique for exploring the human body. Many of these pioneers who use X-rays are victims of radiation dermatitis, or burns to the hands that, in the most severe cases, lead to amputations and even death. Regulation of the use of X-rays and implementation of radiation protection measures would not come before the late 1920s.
Picking up the work of the French physicist Henri Becquerel, Pierre and Marie Curie give the name "radioactivity" to the property possessed by certain elements of spontaneously emitting radiation. In 1898, Marie isolates polonium and radium, both of then unknown and highly radioactive elements. Medicine grabs radium and makes it the tool in the fight against cancer. Praised for its benefits, radium becomes a source of rejuvenation for the public and a source of profit for manufacturers. It will take time and evidence to admit the danger of its radiation…
In 1934, Irene Curie and her husband Frederic Joliot discover that it is possible to artificially produce radioactive atoms. The discovery will lead to another breakthrough discovery: the fission of uranium. From the 1940s, small sources of radium and polonium available to the pioneers are replaced by larger machines: nuclear reactors and particle accelerators. Applications of radioactivity are multiplying and radiation protection musts adapt.
This film tells the story of the Radiation Protection since the discovery of X-rays and radioactivity until today. Radiation protection was built gradually. First, on a principle of limitation until 1950: prevent deterministic effects, which appear above a certain threshold of exposure. Later, during the second part of the 20th century, on a precautionary approach: use radiation only if they are useful and provide a real benefit, and maintain exposures as low as reasonably possible.
Between 1945 and 1980, Russia, the United States, Britain, France and China carried out more than 500 atmospheric nuclear tests. Each explosion released into the environment large amounts of radioactivity. In March 1954, the USA conduct a new atmospheric test of an hydrogen bomb. The radioactive cloud flies over inhabited islands and touches the Lucky Dragon, a Japanese tuna fishing boat. The public becomes aware of the risk of massive contamination of the planet by radioactive pollutants. Radiation protection, so far restricted to the workers, now extends to humans and the environment.
In a nuclear facility, areas exposed to radiation are most often located in what we call controlled areas. Workers entering such an area must wear special clothing and protective gear. Their profession, activities and work methods are inconceivable without some form of radiation protection.
As soon as the French nuclear industry develops in the early 1970s, it becomes necessary to monitor its facilities and control discharges with particular care. Until the 1990s, radioecology was a discipline devoted entirely to the radiation protection of man. By verifying that the impact of discharges was negligible for man, it was believed that it was also negligible for other species. However, this has now been called into question. And as a result, monitoring has changed. It now also monitors radioactivity in flora and fauna and the various parts of the ecosystems.
We live in a pool of radioactivity since the world began. An average of 240 particles per m² fall on France every second. This exposure caused by cosmic radiation accounts for 10% of the naturally originating exposure to which we are all subjected. Fortunately, the Earth has a magnetosphere and an atmosphere. Without these two protective envelopes, radioactivity would be so strong that it would make life impossible...
The earth contains a great many natural radioactive elements (such as uranium, thorium and potassium). Uranium, for example, is present in all rocks, and in particular granite rocks. When it decomposes, it gives rise to a radioactive family, ultimately forming lead, which is stable. Radon is one of the radioactive decay products of uranium. Its distinguishing sign is that it is a gas. And as it is a gas, it escapes and accumulates in caves or galleries, which are enclosed spaces. During the first few years when French uranium deposits were mined, the miners breathed air in which the radon content could be as high as 20,000 Becquerels per cubic meter. Epidemiological studies on uranium miners have shown that radon is a carcinogenic agent that can cause lung cancer. More recently, studies on the general population have confirmed this risk for exposure to radon in the home.
Discovered more than a century ago, X-rays are still topical, with the use of digital imaging in medicine. Conventional radiography is still the best way of looking at bones, and viewing certain organs such as the digestive system or the arterial system, by injecting a contrast medium. But it only gives a flat view on which the shadows of the organs can merge into one another. The X-ray scanner, invented in the 1970s, overcomes this drawback. Despite the precision of the images, we can’t see everything with X-rays or check that an organ is working correctly. For this, doctors use another technique using radioactivity, which was developed in the mid-twentieth century: nuclear medicine.
Our body is made of billions of cells which are arranged to form organs. Approximately one and a half metres of DNA are stored in each cell. DNA undergoes permanent attacks and there a numerous aggressive agents. The following can be mentioned: solvents and pesticides, combustion smoke, viral aggressions, ultraviolet radiation, ionising radiation. All molecules can be affected by radiation, but it is when DNA is impacted that there are the greatest consequences for cellular operation.
There are some parts of Europe where people still follow their ancestral way of life. In Lapland, in the far North, the Sami have been breeding reindeer for thousands of years. They also fish, hunt and gather all the food this wild countryside dotted with lakes and forests can provide them. But since Chernobyl, much has changed.