Radiation in Everyday Life Teo Jim Yang 3O3(26)

Contents Basics Radiation in Our Environment Effects of Radiation Definition Ionizing and Non-ionizing radiation Electromagnetic Radiation Natural Background Radiation Man-Made Radiation Radiation in Our Environment Effects of Radiation Sources of radiation in everyday life Significance of Radiation Exposure People who are at higher risk Radiation Protection

What is radiation? Energy that travels through space in the from of particles or waves Two different types of radiation: ionizing and non-ionizing Radiation can be found all around us

Ionizing and Non-ionizing Radiation Has a lot of energy that gives it the ability to cause changes in atoms Enough to damage DNA Overexposure can cause: Mutations in your genes, which causes birth defects, Raised risk of cancer, burns Radiation sickness Non-ionizing Radiation Relatively low-energy radiation that doesn't have enough energy to ionize atoms or molecules Although considered less dangerous than ionizing radiation, overexposure to non-ionizing radiation can cause health issues

Ionizing and Non-Ionizing Radiation

Summary of Radiation

Natural Background Radiation Refers to the naturally derived, widespread radiation present everywhere in the environment Usually not detrimental to life 3 Main sources: Cosmic Radiation Cosmic rays from outer space which bombard the earth Terrestrial Radiation Radioactive substances in the earth's crust Soil Water Vegetation Emanation of radioactive gas from the earth (radon gas) Internal Radiation Trace amounts of radioactivity in the body Emanation - emission

Man-Made Radiation Two distinct groups of people exposed to man-made radiation sources: Members of the public Occupationally exposed individuals

Man-Made radiation Sources that results in exposure to public: Tobacco (thorium) Television (EM radiation) Medical Procedures Diagnostic X-rays Nuclear medicine Smoke detectors (Americium) Building materials (Radon) Occupational sources Radiography X-ray technicians Workers in Nuclear power plant Nuclear medicine technicians The bricks, stones, cements and drywalls that we use for the building of our homes, schools, offices frequently contain uranium ores and are thus sources of radon.

Electromagnetic (EM) Radiation Light is made up of different components: Gamma Rays X-Rays Ultraviolet Rays Visible Light Infrared Rays Microwaves Radio Waves They make up the electromagnetic spectrum They emit radiation Decreasing in Wavelength Decreasing in Wavelength

Effects Of Radiation And much more… Increased blood pressure Lesions "Harmful Effects of Radiation" Video Increased blood pressure Lesions Damage to foetus (in pregnant women) Mental retardation Miscarriage Cancers: Salivary gland cancer Lymphatic cancer Bone marrow cancer (leukemia) Brain cancer Breast cancer Heart Disease Headaches And much more…

Effects of Radiation Why does radiation cause harm? DNA Damage Our cells have mechanisms to repair DNA damage to a limited extent but radiation can overwhelm these mechanisms. Damaged DNA is implicated in several disease processes, including various types of cancer. Interference with Melatonin production Low melatonin levels have already been linked to several diseases, including cancers Interference with Cellular Communication Our body cells communicate internally and externally by means of electrical signals.  These signals can be altered by EMF radiation which generates electrical currents within the body causing changes in both cellular activity and cellular structures

Effects of Radiation Factors affecting the effect of radiation: Intensity of radiation Exposure to strong radiation may cause damage, even though the exposure is of short duration Cumulative Exposure The combination of the different frequencies a person is exposed to may overwhelm the body defenses and repair mechanisms. Duration of Exposure Many studies have indicated that various health effects are only noticed after many years of exposure to  electromagnetic pollution, for example high voltage power lines, or cell phones. Radiation Transience More biologically stressful to be exposed to fluctuating radiation which arises from an electrical appliance which cycles on and off than from a similar appliance that remains steadily on all day. 

Sources of Radiation in Everyday Life Cell-phones Tobacco Smoke from smoking Medical Use of Radiation Radiation from Appliances Televisions and Computers Microwave Ovens Heating Appliances Personal Grooming Appliances

1. Cell Phone Radiation Radiation in cell phones is generated in the transmitter and emitted through the antenna In the form of radio waves These waves picked up by a receiver in the cell-phone tower

1. Cell Phone Radiation When talking on a cell phone, most users place the phone against the head Some of the radiation might be absorbed by human tissue Radio frequency (RF) radiation has the ability to heat human tissue Damage to tissue can be caused by exposure to RF radiation because the body is not equipped to dissipate excessive amounts of heat The eyes are particularly vulnerable due to the lack of blood flow in that area Use of cell phones may have potential links to: Cancer Brain tumors Alzheimer's disease Parkinson's disease Headaches

1. Cell Phone Radiation Some precautions that can be made to reduce RF radiation exposure from cell phones: Extend the antenna during use Use a phone that places the antenna as far away from you as possible Use a hands-free headset Limit calls inside buildings Use the phone in open spaces as often as possible Limit use by children

2. Radiation from Smoking Cigarette smoke contains radioactive lead-210 and polonium-210  Each cigarette smoked can also be equated to one chest x-ray A non-smoker living with a smoker may receive the equivalent of 12 chest x-rays per year as a result of second-hand smoke Lead-210 and polonium-210 are deposited in the bronchioles Risk of cancers is increased with the presence of other harmful substances in cigarette smoke Carbon monoxide Tar Nicotine

3. Radiation In Medicine Diagnostic radiology Use of machines (e.g. X-ray) to obtain images of the inside of the patient's body X-rays can penetrate skin Bone, fat, muscle, tumors and other masses all absorb X-rays at different levels The image on the film reveals distinct structures in the body because of the different levels of exposure on the film Even with the risks, X-ray scanning is still a safer option than surgery Other diagnoses using radiation include mammography and MRI scans

3. Radiation In Medicine Radiotherapy Use of high energy x-rays and similar rays to treat disease (usually cancer) Radiation destroys the cancer cells in the treated area Although normal cells can also be damaged by the radiotherapy, they can usually repair themselves Contributes to 40 per cent of all cured cancers

4. Radiation from Appliances Televisions TVs emit X-rays LCD (flat screen) TVs produce much less radiation Computers Computers emit radio and microwaves Wireless equipment (e.g. mouse, keyboard) also emit some radiation Sit at least: 1.9m away from TV 60 cm away from computer screens It's better for your eyes too

4. Radiation from Appliances Microwave Ovens Microwaves affect the food Structure of protein foods is changedso that a beneficial protein molecule in the food becomes a harmful one Placing plastic containers into the microwave may cause toxic plastic molecules to leach into the food Microwaves also leak out of the oven keep a distance of 1.5 meters It's better for your eyes too

4. Radiation from Appliances Heating Appliances Electric blankets generate EM radiation, even after switched off Electrically heated carpets and rugs, under-carpet and under-floor heating all produce substantial EM radiation Electrical heaters also produce lot of EM radiation

4. Radiation from Appliances Personal Grooming Appliances Hairdryers, electric shavers, electric toothbrushes and similar personal grooming products emit radiation at their normal operating distance People at higher risk should refrain from using them It's better for your eyes too

Significance Even though common sources of radiation only deal it in minute doses The frequency of which we are exposed to them are greater causes for concern The accumulation of these small doses may greatly affect our health

People at Higher Risk Children Pregnant Women Biologically more vulnerable Thinner skulls Tissues not fully developed May not be able to control how much they use cell phones, play on computers, watch TV etc, and how close they sit to the screen. Pregnant Women Any cellular damage in a developing embryo may have magnified consequences for the child At risk of miscarriage if they are subjected to high intensity EM radiation during pregnancy Lower EM radiation levels may still damage the foetus while not causing an actual miscarriage.

People At Higher Risk People already suffering from chronic degenerative conditions The body is already using all its available energy to heal itself Does not have much energy to spare for repairing the damage done by radiation Workers in close proximity to electrical machinery Exposed to strong electromagnetic fields and radiation

People At Higher Risk Frequent users of appliances that emit radiation Spend more than a few minutes a day talking on a cell phone pressed to their ear etc Table of Radiation-emitting Appliances Especially vulnerable if they done every day for years In other words, most of us are at risk

Radiation Protection Increase distance from source The intensity of radiation decreases with distance from its source. Reduce time exposed to source If exposure cannot be avoided, try to spend as little time near it as possible If it doesn't need to be turned on, switch it off Radiation comes from many devices which are left on unnecessarily, e.g. charger units for batteries, cell-phones, laptops etc, computers and printers

Radiation Protection Shielding Containment Barriers of lead, concrete or water give good protection from high levels of penetrating radiation such as gamma rays Intensely radioactive materials are often stored or handled under water, or by remote control in rooms constructed of thick concrete or lined with lead Containment Highly radioactive materials are confined and kept out of the workplace and environment Nuclear reactors operate within closed systems with multiple barriers which keep the radioactive materials contained

References http://www.world-nuclear.org/info/inf05.html http://www.world-nuclear.org/education/ral.htm http://science.howstuffworks.com/radiation.htm http://www.wisegeek.com/what-is-electromagnetic-radiation.htm http://www.howstuffworks.com/cell-phone-radiation.htm http://www.hps.org/publicinformation/ate/q824.html http://www.uraniumsa.org/about/radiation.htm http://www.radiationanswers.org/radiation-introduction/types-of-radiation.html

References http://orise.orau.gov/reacts/guide/define.htm http://www.chem.duke.edu/~jds/cruise_chem/nuclear/exposure.html http://www.docstoc.com/docs/23411087/Natural-and-Man-Made-Radiation-Sources http://www.emwatch.com/index.html http://www.uihealthcare.com/topics/medicaldepartments/cancercenter/prevention/preventionradiation.html http://www.epa.gov/radiation/sources/tobacco.html http://www.hpa.org.uk/Topics/Radiation/UnderstandingRadiation/UnderstandingRadiationTopics/MedicalRadiation/ http://health.howstuffworks.com/medicine/modern/nuclear-medicine.htm