Radioactive Pollution is defined as the increase in the natural radiation levels caused by human activities. It is estimated that about 20% of radiation we are exposed to is due to human activities. The human activities that can release radiation involve activities with radioactive materials such as mining, handling and processing of radioactive materials, handling and storage of radioactive waste, as well as the use of radioactive reactions to generate energy (nuclear power plants), along with the use of radiation in medicine (e.g. X-rays) and research. But what about microwaves, cell phones, radio transmitters, wireless devices, computers, and other common commodities of today’s life?
When we think of radiation, we imagine bombs and nuclear explosions. While these are serious sources of high levels radiation (of high energy), there are many other sources that are much more common, practically ubiquitous, that generate low levels of radiation and which basically remain unnoticed. How many of us think for example of cellular phones as a source of radiation? And yet, the cell phones, cell phone towers, cordless phones, as well as TVs, computers, microwave ovens, broadcast antennas, military and aviation radars, satellites, and wireless internet are all sources of radiation. And so are the common medical X-Rays. Considering this, the picture of radiation pollution significantly expands. From a few explosions and nuclear accidents happening relatively rarely in faraway places, the picture of radiation pollution expands to a complex matrix covering all the Earth and thus involving all of us everywhere! In this context, we could ask ourselves: is radiation really so bad? Yet, if it were, wouldn’t we all be dead or sick by now?!
Radiation is essentially energy that travels and spreads out as it goes. This is referred to as electromagnetic radiation. Examples include visible light, radio waves, microwaves, infrared and ultraviolet lights, X-rays, and gamma-rays. The differences between these various types of radiation consist of some physical properties such as energy, frequency, and wavelength. Thus, there are a variety of electromagnetic radiations. This means that any and all these types of radiation can generate radiation pollution if they are enhanced by human activities. However, the magnitude of the pollution generated varies, with higher-risk pollution generated by radiation of higher energy such as gamma-rays regardless of exposure time. This radiation is generated through detonation of nuclear weapons or in power plants. Therefore, the meaning of radiation pollution is that, while there are ubiquitous sources of radiation, it is mostly the high-energy radiation that causes radiation pollution, carrying serious health risks (such as cancer or death). This is why we will focus on sources for high health-risk radiation when discussing the causes of radioactive pollution and its effects. However, the other types of radiation (in low doses over longer time) may still cause health problems, including neurological, reproductive, and cardiac dysfunctions.
Types of Radioactive Pollution
Based on the frequency with which it occurs, radioactive pollution can be continuous, occasional or accidental.
Continuous radioactive pollution is the type of pollution constantly coming from uranium mines, nuclear reactors, and test laboratories, where the radioactive contaminants are always present.
Occasional radioactive pollution is the type of pollution that occurs during nuclear tests or during experimental tests on radioactive substances.
Accidental radioactive pollution is the type of pollution that occurs when certain experiments involving dangerous substances fail, and the substances used for experimentation get out of control.
Examples of Radioactive Contaminants
Radioactive materials are those materials or elements that emit radiation, thus they are not stable and get transformed into other radioactive or non-radioactive materials. The harm that they can cause depends on the radioactive elements and their half time function (the time needed for their concentration to be reduced to half due to radioactive decay processes). Basically, the higher the half-time, the lower the effects on human health. Radioactive elements with a short and very short half-time pose a serious threat to human health because of their hazardous effects. Most of the radioactive materials have half-lives of hundreds of thousands of years and, once generated, may persist in the environment for a very long time.
Many radioactive elements (materials) are naturally present in the environment. Most of them are used in nuclear power plants, and as basic components of nuclear weapons. Examples of this type of materials are Caesium-137, Strontium-90, Plutonium-238, Uranium-235. Other examples of radioactive elements with include: Chromium-51 (used in studies of red blood cell survival), Cobalt-57 and Cobalt-60 (used in nuclear medicine ), Calcium-47 (used in biomedical research), Iodine-123 (used to diagnose thyroid diseases), Krypton-85 (indicator lights), Nickel-63 (used in explosives detection), Radium-226 (lightning rods), Strontium-85 (used in the study of bone formation), Thorium-229 (fluorescent lights), Tritium (used in drug metabolism studies), Uranium-234 (used in dental fixtures like crowns). Radon is also a common radioactive element and represents about 55% of the natural radiation.
The Effects of Radioactive Pollution
Depending on the amount of radiation to which we are exposed and the sensitivity of each exposed person, the effects of radioactive pollution can vary significantly between individuals. While the exposure to high amounts of radiation generates almost immediately chronic diseases, cancer or even sudden death in rare cases of extreme pollution, small amounts of radiation can cause diseases that are not so serious and develop over the course of time. The risk of developing cancer increases with the dose of radiation, but lower doses of radiation can also cause cancer after years of exposure.
Exposure to radon is the second leading cause of lung cancer in the U.S.! (please note that the risk of developing lung cancer increases with smoking). Also, the exposure to other similar radioactive materials can generate neurological, reproductive or heart problems. These may or may not be followed by cancer. If the parents are exposed to radiation before or during pregnancy, genetic birth defects and retardation may occur in the fetus.
Genetic inheritance plays an important role in how sensitive an individual may be to radiation-based pollution. However, any amount of radiation may cause cancer, and any exposure to radiation may cause some health risks. Thus, it is always safer to minimize as much as possible the exposure to radiation!