How and why can radiation be dangerous?

Radiation permeates the world around us in its various forms. It is invisible, omnipresent, essential to life, and at the same time a destructive force.. So what really makes radiation so dangerous to humans?

What happens in our bodies when we are exposed to radiation, either accidentally or from an artificial source, when subatomic particles encounter our tissues, pass through our cells and reach our DNA?

To answer this, we need to understand what radiation is, how it interacts with living matter, and the specific types that can harm us.

The history of radiation begins in the late 19th century, when scientists Wilhelm Röntgen, Henri Becquerel and Marie Curie began to investigate mysterious phenomena in physics. In 1895, Röntgen discovered X-rays, a type of radiation that can pass through the skin and reveal internal structures such as bones.

Shortly thereafter, Henri Becquerel discovered radioactivity by observing that some elements, such as uranium, emit an invisible energy that could penetrate even solid objects. Shortly thereafter, Marie Curie and her husband Pierre Curie performed fundamental experiments with radioactive materials.Elements such as radium and polonium helped establish the concept of elements that naturally emit radiation.

“These discoveries opened incredible doors to medicine and nuclear science, but also introduced the danger of radiation that was initially underestimated.”

Early scientists interested in radioactive materials, such as Marie Curie, were unaware of the risks and harmful effects of long-term exposure to radiation and suffered serious health problems, even death.

By definition, radiation is the emission of energy through particles or electromagnetic waves. There are two main types: ionizing and non-ionizing radiation.. Non-ionizing radiation includes radio waves, microwaves, and visible light, which are generally harmless to the human body at normal levels.

Ionizing radiation is anything that has enough energy to remove electrons from atoms and molecules and turn them into ions.

Ionizing radiation can be divided into three main types

Alpha radiation (a)

This type of radiation consists of particles formed by two protons and two neutrons (the nucleus of a helium atom). Although highly ionizing (capable of destroying atoms by removing electrons from atoms), alpha particles have a low penetrating ability.

They cannot pass through human skin, but if a source of alpha radiation is ingested or inhaled the damage can be devastating. Polonium-210, for example, is an extremely dangerous radioactive element in its alpha form and can be lethal if swallowed..

Beta radiation (ß)

It consists of high-energy particles, electrons or positrons. beta radiation can penetrate deeper into human skinbut it usually does not reach internal organs in high concentrations. But long-term exposure can cause tissue damage such as radiation burns or, in extreme cases, increase the risk of cancer.

Gamma Radiation (y)

Gamma radiation is high-frequency electromagnetic waves similar to light but with much greater energy. They have extremely deep penetration and can penetrate meters of concrete and even the human body.

Gamma radiation can cause serious damage to internal cells and tissues. When not properly controlled it becomes the most dangerous form of radiation.

Ionizing radiation is dangerous because it can break chemical bonds in molecules, especially cell DNA. When this happens, cells can undergo mutations that will make them cancerous or die at high doses.

The effects of radiation vary depending on dose and exposure. The common unit of measurement for dose absorbed by the body is the sievert (Sv), and small doses of radiation, such as those used in x-rays, are relatively safe. But high doses, such as those released in nuclear accidents, can be fatal.

Biological effects of ionizing radiation

acute exposure

High doses of radiation over a short period of time can cause radiation poisoning, with symptoms ranging from nausea and vomiting to damage to vital organs. In extreme cases, this exposure can lead to death within a few days or weeks, depending on the dose.

Long-term effects

Repeated exposure to even low doses of radiation can lead to the accumulation of cellular damage, increasing the risk of developing cancers, especially leukemia and skin cancers.

genetic effects

Radiation can cause mutations in genes that can be passed on to future generations. This occurs especially when exposure affects reproductive cells.

The dangers of radiation were clearly demonstrated in events such as the bombings of Hiroshima and Nagasaki in 1945; Nuclear explosions released deadly gamma radiation, killing hundreds of thousands of people and leaving a legacy of genetic diseases to future generations.

Another example is the Chernobyl disaster in 1986; radiation exposure here has led to numerous deaths and cases of cancer occurring over decades.

Following these events, science sought to better understand radiation and ways to protect it, which led to the creation of strict safety protocols. For those who work with radioactive materials in nuclear power plants, in medicine or research.

For these reasons, today it is possible to use it in different ways, use it safely, minimize its dangers and expand its benefits.