Students’ Knowledge of Nuclear Science and Its Connection with Civic Scientific Literacy in Two European Contexts: The Case of Newspaper Articles

Abstract

Nuclear science has uses and applications that are relevant and crucial for world peace and sustainable development, so knowledge of its basic concepts and topics should constitute an integral part of civic scientific literacy. We have used two newspaper articles that deal with uses of nuclear science that are directly relevant to life, society, economy, and international politics. One article discusses a new thermonuclear reactor, and the second one is about depleted uranium and its danger for health. 189 first-year undergraduate physics and primary education Greek students were given one of the two articles each, and asked to answer a number of accompanying questions dealing with knowledge that is part of the Greek high school curriculum. The study was repeated with 272 first-year undergraduate physics, physics education, science education, and primary education Turkish students. Acceptable or partially acceptable answers were provided on average by around 20 % of Greek and 11 % of Turkish students, while a large proportion (on the average, around 50 % of Greek and 27 % of Turkish students) abstained from answering the questions. These findings are disappointing, but should be seen in the light of the limited or no coverage of the relevant learning material in the Greek and the Turkish high-school programs. Student conceptual difficulties, misconceptions and implications for research and high school curricula are discussed.

Appendix: The Newspaper Articles Used in the Study

NOTES

• 1. For economy of space, the articles have been slightly abridged.

• 2. In the actual questionnaires, in each text the lines were numbered, and in the questions the lines were noted in which the relevant text was located. Emphasis was added by the authors of this article, to focus students’ attention on the terms and phrases that were relevant to the questions.

1.1 ARTICLE A, ITER: The reactor that is going to change the world [Adapted from Varvoglis (2005)]

Following long years of negotiations about the construction of the thermonuclear reactor in the French town of Cantarache, a consortium of countries has finally started to put the project into effect…. Its successful operation will be a milestone for our technological civilization entering a new era. …There is already a consortium of nations working in what seems to be on good track. This consortium aims at the construction of the first experimental thermonuclear reactor, which will prove the possibility of constructing electric power plants by using as energy source the fusion of hydrogen to helium. The energy released when 1 gram of hydrogen atoms (1 mol of atomic hydrogen) undergoes the fusion reaction is equal to the energy released from burning about 23.000 liters of gasoline. This is a very large amount of energy, covering Greece’s energy needs for 1 h.

Since 1954, when the first testing of the hydrogen bomb was carried out, physicists had already been trying to develop a peaceful use of this new source of energy, hydrogen fusion. However, that target proved much more difficult to achieve than the corresponding effort to harness atomic energy from the decomposition (fission) of uranium. The reason is that the hydrogen fusion occurs at high temperatures (of million degrees centigrade), while even the most resistant materials available on the Earth melt at 3,000 or 4,000 degrees centigrade. So, how can a reactor be constructed which can resist such high temperatures?

Many ideas and techniques have been tried since 1954. One idea which proved the most successful was to use a magnetic field as a sort of the reactor’s “invisible wall”. At the high temperatures required for the fusion, the hydrogen is ionized, and the gas is then a mixture of protons and electrons. This mixture is referred to as plasma. According to one fundamental law of physics, the plasma is “repelled” away from the regions where there is a strong magnetic field. Therefore, all we need to “keep” the plasma in the thermonuclear reactor is a serious of magnets, placed in a manner that the resulting magnetic field will be weak in the reactor’s center and strong near its side walls. …

All the countries participating in the Consortium were willing to host the thermonuclear reactor, because it is “clean” and safe, unlike the uranium atomic reactors, which are always in danger of exploding or producing radioactive waste. Ultimately, it seems that the ongoing increase in the oil prices has had a decisive effect on the negotiations, resulting in the decision to construct the thermonuclear reactor in the French town of Cantarache, as supported by the European Union.

The successful operation of the ITER reactor will constitute one of the most significant technological milestones of our civilization. It will mark the definite withdrawal of mankind from the most important sources of energy used to this day, that is, coal and oil. If one looks back at the few recent centuries in human history, one will realize that most major wars were waged in pursuit of possessing and managing of energy resources, which have always been located in small regions around the globe and have been of limited capacity. In contrast, hydrogen exists in water, therefore we can obtain it from water. In this way the energy problem of the residents of this planet can be regarded as solved for thousands of years to come.

1.2 ARTICLE B, Depleted Uranium: A disastrous nuclear waste [Adapted from Vagena (2001) and Bitsika (2001)]

During the 1980’s, the Military Industry developed and started mass production of a new highly penetrating missile. The high penetrating material used in this missile derived from a nuclear waste called depleted uranium (or DU for short). The producers were proud for the havoc (disaster) caused to military tanks by this missile, that they nicknamed it “tank-killer”.

Depleted uranium is the by-product that is left behind by the process of enriching the mineral of uranium, which is used as the fissionable material in nuclear plants. The radioactive mineral uranium (U) that exists in nature consists mainly of two isotopes, U-235 (²³⁵U) and U-238 (²³⁸U), as a rule in proportions of 0.7 % and 99.3 %, respectively. U-235 is used in nuclear reactors to produce huge amounts of energy by means of the nuclear fission reaction, while U-238 is not useful in that (U-235 has a higher fission probability to undergo fission, while the U-238 has small probability). Therefore, it is essential that natural uranium is enriched by means of a special process that removes a large part of U-238 while leaving behind U-235. The U-238 that is obtained in this way is called depleted uranium. Having a half life of 4.5 billion years (!), U-238 in practice never decomposes. (U-235 has a half life of 704 million years.)

A 30 mm DU missile contains about 4.650 fragments of DU, weighing approximately 300 grams. When it explodes, splinters and radioactive material in the form of very fine dust disperse over a over a large distance, and, practically, they remain there forever, polluting the soil and the water-carrying zone. Extended use of DU missiles was reported for the first time during the Gulf War in 1991 and a few years later in the War in the Balkans.

Depleted uranium is still controversial about its consequences on public health and the environment, which are due to its radioactivity. The World Health Organization (WHO) refers to the dangers from depleted uranium, pointing out that it does not cause leukemia, but it can have toxic action on the human organism, affecting kidneys and lungs. In addition, deaths have been reported of soldiers who participated in the Iraqi warfare, which were attributed to what is known as the Gulf Syndrome. Concern has also been expressed about a problem that might be caused if depleted uranium enters the food chain through the water-carrying zone in the Balkan territories, where the bombs were thrown.

(Nuclear physicist) Dr. Athanasios Geranios claimed that the slightest exposure to radioactivity is serious. … The maximum permitted limit of 0.2 rem coming from the dose we receive annually from natural radioactivity allows for only one chest X-ray per year! As a result, there is no margin for additional dose of radioactivity. Note that this not a case of a personal choice, but something enforced to us by others or it happens without our being aware of it. As Dr. Geranios explained, … there will be an approximate 10-year latent period for the likely appearance of symptoms of illness related to radioactivity. Following that is the so–called plateau, which may last even 30 years, and during this period there is probability for cancer…. Of great importance are the age, the type of radiation, and the dose received at the beginning of the period…

Finally, according to the USA Department of Energy, since 1930, the annual permitted radioactivity for nuclear workers was 156 rem (this dose also depends on the kind of radiation, and which is ten times higher for alpha particles than for gamma or X rays), while 600 rem is the deadly dose. However, this limit is gradually lowered, reaching 15 rem by the 1950s, further reduced to 5 rem in the period 1960–1990… For the general population (but not the nuclear workers) this value is currently set at the 1/10, that is, 0.2 rem.