Can Humans Be Contaminated with Radioactivity and What Does That Mean for Us?

Introduction:

The concept of radioactivity is often associated with nuclear accidents or other man-made disasters, but the reality is that radioactivity is not a modern invention. In this article, we will explore the natural occurrence of radioactivity in the human body and how we are constantly surrounded by it. We will also address the role of natural radioactivity in our evolution and how to measure it.

Radioactivity from Naturally Occurring Plutonium

While many people think of plutonium as a man-made element, there is a small amount of naturally occurring plutonium on Earth. This plutonium is incorporated into the human skeleton, with estimates suggesting that humans carry a base load of between 10^3 to 10^5 atoms of plutonium in their bodies. The amount of plutonium in the environment has significantly increased since 1945, which has many interesting implications for human exposure and health.

Can Humans Be Radioactive?

A common question is whether humans can be radioactive. The answer is a resounding yes. Not only can we be radioactive, but there are several types of naturally occurring radioactivity in the human body. It's important to note that while radioactivity is a real concern, the naturally occurring background radiation is generally safe in our daily lives.

Natural Sources of Radioactivity in Humans

Carbon-14: Organic matter, such as cotton in bedsheets, can be slightly less radioactive than living matter. Even sleeping with someone can expose you to a higher radiation dose. This is because organic matter from the surrounding environment becomes part of our bodies. Uranium and Thorium: The major contributors to natural radioactivity in humans are K-40, uranium-238, and uranium-235, which are naturally occurring in the human body. Potassium-40 is particularly found in bananas and is responsible for increasing radiation levels in the human body. Radon: Another common source of natural radioactivity is radon, a radioactive gas that can accumulate indoors and in caves. Inhalation of radon is a significant source of radiation exposure for many people. Chernobyl, Fukushima, and Atmospheric Testing: While these events dramatically increased the level of artificial radiation, the Earth's natural radioactivity should not be ignored. The earth is rich in radioactive materials, making it impossible to avoid all forms of radioactivity.

The Role of Low-Level Radioactivity in Evolution

Interestingly, low-level radioactivity has played a role in human evolution. Mutation due to radiation can lead to genetic changes over time, which can be a factor in the evolution of species. While this natural radiation is not necessarily harmful, it does contribute to the overall genetic variation in a population.

The Measurement of Natural Radioactivity

There are various methods to measure the natural radioactivity in the human body. Some individuals even have radiation detection instruments, like John, who uses an instrument sensitive enough to detect the natural activity. This can help in studying the levels of radioactivity and understanding how different elements like potassium-40 can be used as a biomarker for vegetarian diets. Here, we can measure the level of radioactivity in a person's body and learn more about their dietary habits.

Conclusion: Radioactivity is a natural part of our environment, and humans are naturally radioactive. While man-made sources of radioactivity need to be carefully managed, the naturally occurring sources of radioactivity should also be considered. Understanding these sources and their implications is crucial for our overall health and well-being.

Keywords:
radioactivity in humans, contamination, natural radioactivity