Radioactivity describes something that occurs in the center of atoms. It was first found in the late 1800’s. Through years of research, it has been determined that atoms which are radioactive release both energy and particles. The particles that are released can be harmful to living things. However, the energy that is released can be used in medical treatments and testing. Use of radioactive substances will always be controversial because it is both helpful and harmful to human beings.

    All matter is made up of tiny particles called atoms. When matter is made up of only one kind of atom, it is called an element. Examples of some elements would be gold, carbon, hydrogen, etc. The center of an atom is called the nucleus. The nucleus contains particles called neutrons. Very tiny particles called electrons fly around the nucleus. Atoms of the same element have the same number of protons. However, atoms of the same elements can have different numbers of neutrons. These are called isotopes.

    Radioactive elements were first discovered in the late 1800’s. A French scientist named Henri Becqurerel discovered that uranium released energy that could change camera film. He shared his discovery with Marie and Pierre Curie. Marie came up with the name radioactivity for the spontaneous release of radiation from the nucleus of unstable atoms. Later, Marie discovered two other radioactive elements that she named polonium and radium

    Radioactivity is defined as the emission or release from unstable nuclei. This means that some atoms have so many neutrons and protons that their nucleus isn’t strong enough to hold them all together and let particles and energy out which is known as radiation. The three types of radiation that can come from radioactive atoms are alpha particles, beta particles, and gamma rays. Alpha particles are made of two protons and two neutrons and have a positive charge. They can’t go through a sheet of paper. Beta particles can form when a neutron changes into a proton and an electron. The proton stays in the nucleus but the electron is released and has enough energy to pass through paper. Thick aluminum foil can stop beta particles. The most powerful radiation is gamma rays which can only be stopped by several inches of lead or three feet of concrete.

   

Since radioactive atoms lose particles from their nuclei, this is called radioactive decay. When neutrons change into protons, the element changes. For example, a radioactive isotope called carbon-14 changes into nitrogen-14. The time it takes for half of a sample of radioactive atoms to decay is called the half-life. Different radioactive atoms have different half lives. For example, carbon-14 has a hale life of 5,730 years while polonium-216 has a half life of only 0.16 seconds.

    Before people realized that radioactive material was dangerous, elements like radium were used in everyday items. Radium was put into toothpaste and even butter. Since it glowed in the dark, it was put into paint that was used on watch numbers and airplane dials. The women who painted with radium were known as “Radium Girls”. Eventually, these women got sick from working with the radium, and many died from cancer.

    The particles and energy that are released from radioactive atoms can be harmful to living things. Alpha particles can cause very harmful burns. Beta particles and gamma rays can travel through the human body causing damage to cells and DNA. Both Marie and Pierre Curie got sick working with radioactive elements. Marie eventually died from cancer. Even her daughter, Irene Joloit-Curie, who continued her mother’s research, died of cancer after long time exposure to radioactive elements. Today, people wear protective clothing to prevent exposure to harmful radiation, as well as use Geiger counters to determine if any radiation is present.

    Even though radioactive elements are harmful, people have found many uses for them. One use is radioactive dating. When scientists know the half life of a radioactive isotope, they can use this information to determine how old a rock is or how long ago a rock formed. Carbon-14 is used to date things like dinosaur bones, mummies, and animals found in glacier ice. Potassium-40 is used to date rocks or tools used by ancient humans.

    Radioactive elements are also used for energy and in medicine. When the nuclei of some radioactive isotopes are split in controlled reactions, they release a huge amount of energy. Nuclear reactors use this energy to generate electricity. It is also used to power nuclear submarines. Doctors use radioactive material in two different ways. If radioactive isotopes are injected in the body, special machines can follow where they go or get collected. These are called tracers and help doctors find organs that may not be working correctly. Another medical use of radioactive material is radiation therapy. Gamma rays can be used to kill cancer cells.

    Radioactivity is a natural but dangerous reaction. Its radiation can make people and other living things very sick or even kill them. Radioactive waste is difficult to get rid of and people are concerned about accidents in nuclear power plants as well as nuclear weapons. However, radioactive material can be used for important things like dating fossils and treating diseases. Radioactivity is both interesting and controversial. Hopefully we will continue to learn more about it and find safer ways to use it.

    By,

    Zachary Baxmeyer