According to recent assessments, the age of the Earth is approximately 6 billion years. However, life only began to appear on Earth about 2 billion years ago. Some suggest that the delay in the emergence of life on Earth could be attributed to the extremely high levels of radiation that dominated the planet right after its formation. Consequently, the first life forms could only emerge when radiation levels significantly decreased in the Earth’s crust and atmosphere.
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In the deep waters of the central ocean regions, the level of Radium is significantly higher than the amount needed to balance with Uranium. |
Water in the oceans contains billions of tons of Potassium, Rubidium, Uranium, Thorium, and Radium. The natural radioactivity of water on land and in the oceans is primarily due to the radioactive decay of Potassium (K40). The concentration of Radium in the surface layers of the ocean is around 0.4-10–10%. In the deep waters of the central ocean regions, the levels of Radium are much higher than those needed to balance with Uranium. Natural sources of water contain Uranium levels ranging from 5·10–7 to 3·10–5 grams per liter. In rivers and streams in the Northern Hemisphere, Uranium levels are lower compared to the waters in the Southern Hemisphere. In swampy areas, the concentration of Uranium can increase to 4·10–2 grams per liter.
The radioactivity of river water is estimated to be around 10–12 Curie/liter, lake water – 10–11 Curie/liter, and seawater – 10–10 Curie/liter. Through the analysis of water accumulation in the atmosphere, it is observed that snow has a higher radioactivity than rain. The processes of snowfall and rainfall act to cleanse the atmosphere of radioactive dust. Fog contains the highest levels of radioactive substances.
In the higher layers of the atmosphere, under the nuclear bombardment of cosmic rays, heavy Hydrogen isotopes – Tritium, which is highly radioactive, is formed and penetrates into the composition of heavy water T2O. Subsequently, it falls to the Earth’s surface with rain and snow. The total amount of Tritium in ocean water is nearly 800 grams, and its half-life is 12.2 years. The concentration of Tritium in ocean water is lower than that in continental water.
This helps clarify the question of how water-laden clouds in the atmosphere are formed – partly due to the evaporation of ocean water and partly from surface water sources on Earth.
The human body contains nearly 3×10–3 grams of radioactive Potassium and 6×10–9 grams of Radium. Due to the presence of these radioactive substances, 6,000 Beta decays and 220,000 Alpha decays occur in the body every second. Additionally, as a result of cosmic ray interactions, other artificial radioactive components appear in the human body. Thanks to the radioactive Carbon isotope C14 (2,500 Beta decays per second), in general, 10,000 decay reactions occur in the human body every second. With the surrounding air, water, and soil all being radioactive substances, the human body itself acts as a radioactive machine, participating in a common process that contributes to the natural “fund” of radioactivity.
Duy Khánh
