By: Emily McGuire, Daysha McMullen, Ja’Bria Coleman, India Lockhart Radiation By: Emily McGuire, Daysha McMullen, Ja’Bria Coleman, India Lockhart

What is Radiation? Definition : the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization. Example : sunshine Ionizing radiation : higher-energy radiation that can cause damage to matter, particularly living tissue. At high levels it can be very dangerous. Example : medical and dental x-rays Used to diagnose ailments and some are treated with it to cure diseases Occurs from uranium ores and nuclear wastes Background radiation : ionizing radiation which is naturally and inevitably present in our environment.

What Causes Something To Be Radioactive? Radioactive decay Occurs in unstable nuclei - ones that don't have enough binding energy to hold the nucleus together due to an excess of either protons or neutrons. Radioactivity - the act in which an atom releases radiation suddenly and spontaneously Radioactivity is caused when an atom wants to give away some of its energy.

3 Types of Radioactivity Alpha Radiation : Alpha particles consist of two protons and two neutrons bound together into a particle identical to a helium nucleus. Produced during alpha decay Named after the first letter in the Greek alphabet Beta Radiation : A high-energy, high-speed electron or positron emitted in the radioactive decay of an atomic nucleus. Also called “beta rays” Produced during beta decay Gamma Radiation : The product of radioactive atoms. Depending upon the ratio of neutrons to protons within its nucleus, an isotope of a particular element may be stable or unstable. Also called “Gamma rays” the most energetic form of electromagnetic radiation, with a very short wavelength of less than one-tenth of a nanometer.

Radiation Penetrating Power

Positive Ways We Use Radiation Alpha Radiation : smoke detectors; Radioactive americium releases alpha radiation, which ionises the air inside the detector. Smoke from a fire absorbs alpha radiation, altering the ionisation and triggering the alarm. Beta Radiation : tracers and monitoring the thickness of materials; Doctors may use radioactive chemicals called tracers for medical imaging; Radiation is used in industry in detectors that monitor and control the thickness of materials such as paper, plastic and aluminium. Gamma Radiation : treatment of cancer, testing equipment and sterilising medical instruments;

Harmful Effects of Radiation Chemical changes in cells that damage them Cells may die or become abnormal, temporarily or permanently Extent of the damage depends on the amount and duration of the exposure, as well as the organs exposed Cancer Large amount : sickness or death within hours or days

Chronic Exposure Cancer Benign tumors Cataracts Potentially harmful genetic changes

Nuclear Radiation Explosions Chernobyl, Ukrainian Largest nuclear disaster April 26, 1986 Overheating, steam explosion, fire, and meltdown Evacuation of 300,000 people from Chernobyl and dispersing radioactive material across Europe Deaths : 30 direct, 19 not entirely related and 15 minors due to thyroid cancer, as of 2008 Fukushima, Japan March 12, 2011 A tsunami flooded and damaged the 5 active reactor plants; Loss of backup electrical power led to overheating, meltdowns, and evacuations Deaths : 2 workers drowned during the flooding, and 1 died suddenly while carrying equipment during clean-up

Sources of Radiation Earth Sun and stars People Terrestrial radiation; Radioactive materials (including uranium, thorium, and radium) exist naturally in soil and rock. Water; water contains small amounts of dissolved uranium and thorium Organic matter; both plants and animals contain radioactive carbon and potassium Sun and stars Cosmic radiation; send down to earth People Internal radiation; radioactive potassium-40 and carbon-14 inside their bodies from birth

Fun Facts Bananas are relatively radioactive The american flags placed on the moon have all been bleached white due to radiation from the sun The average smoker receives an annual dose of radiation equivalent to about 300 chest x-rays due to radioactive isotopes in the smoke.