INTRODUCTION Radiation is energy that moves through space or matter at a very high speed This energy can be in the form of particles eg alpha or beta particles which are emitted from radioactive materials or ID: 1032248
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1. RADIATION AND HEALTHBELLO C. B.
2. INTRODUCTION Radiation is energy that moves through space or matter at a very high speed. This energy can be in the form of particles, e.g. alpha or beta particles, which are emitted from radioactive materials, or waves e. g light, heat, radio-waves, microwaves, x-rays and gamma rays.“Radioactive materials, also known as radio-nuclides or radioisotopes, are atoms that are unstable. In nature, there is a tendency for unstable atoms to release radiation as they change form
3. INTRODUCTION CONTDRadiation that can produce ions when it interacts with matter is called ionizing radiation. Alpha particles, beta particles, x-rays and gamma rays are forms of ionizing radiation. Radiation that is not capable of producing ions in matter is known as non-ionizing radiation. Radio-waves, microwaves, heat waves, visible light and ultraviolet radiation are forms of non-ionizing radiation.
4. IONIZING RADIATIONIonizing radiation is a type of energy released by atoms that travels in the form of electromagnetic waves (gamma or X-rays) or particles (neutrons, beta or alpha). The spontaneous disintegration of atoms is called radioactivity, and the excess energy emitted is a form of ionizing radiation. Unstable elements which disintegrate and emit ionizing radiation are called radio-nuclides.
5. IONIZING RADIATIONThe term “ionizing radiation” is applied to radiation that has the ability to penetrate tissues and deposit its energy within them. There are 2 types:Electromagnetic radiations- x-rays and gamma raysCorpuscular radiations- alpha particles, Beta particles (electrons) and protons.Alpha particles are 10 times as harmful as X-rays, beta particles or gamma rays, Alpha particles though have little penetrating force, they are very dangerous when entered into the body.X-ray and gamma ray have short wave length, they are deep penetrating radiations.
6. IONIZING RADIATION CONTDX-rays are man made while gamma rays are emitted spontaneously by radioactive elements during their disintegrationCosmic rays also contain ionizing radiations
7. NON –IONIZING RADIATIONNon-ionizing radiation includes several forms of electromagnetic radiation of wavelengths longer than those of ionizing radiation. All non-ionizing forms of radiation have less energy than ionizing radiations.Non-ionizing radiation includes ultraviolet (UV) radiation, visible light, infrared radiation, microwave radiation, and radio frequency radiation.Non-ionizing radiation is found in homes and occupational settings, they pose a considerable health risk to potentially exposed workers if not properly controlled
8. SOURCES OF IONIZING RADIATIONThe sources of radiation to which man is exposed are divided into2 groups.Natural sourcesMan made sources.You cannot go through life without radiation, we are exposed to natural radiation from cradle to grave. But always good to keep yearly dose to a minimum.
9. NATURAL SOURCESNatural radiation arises from 3 sources:A. Cosmic rays- the cosmic rays which originate in outer space are weakened as they pass through the atmosphere. At ordinary living altitudes, there impact is about 35mrad/year, At altitude above 20km, cosmic radiation becomes important (pilots).
10. NATURAL SOURCESB. Environmental sourcesI. Terrestrial radiation, radio active elements such as thorium, uranium, radium & isotope of potassium are present in soil, rocks, water, buildings.Man derive about 50mrad/year but in areas with rock formation containing uranium it can be as high as 2,000 mrads/year. E.g Kerala in India
11. NATURAL SOURCES ii. Atmospheric radiation- this is air-borne and may be from radioactive gases such as radon & thorion in the atmosphere. Though very small, about 2mrad/year C. Internal radiation- this is radiation from radioactive matter stored in the body tissues. This include uranium, thorium, potassium (K40), strontium (Sr90), & Carbon (C14). Internal radiation may inflict about 25mrad/year but may be as high as 70-80mrad.
12. MAN MADE SOURCESMan made radiation have numerous beneficial uses: lasers and radiographs are useful for diagnosis of disease and production of nuclear energy.Found in homes as television, microwave oven, smoke detectorsAlso bombs can be laced with radioactive materials.Irrespective of the source, radiation is a threat to human life. The degree of danger depends on the dose and the type of radiatio.
13. MAN-MADE SOURCESX-rays: Today, medical & dental x-rays machines are the most common human-made sources of ionizing radiation used for diagnosis and treatment. Patients, Radiologists & medical technician are the distinct group involved. Skin dose to the pt from a single X-ray film varies roughly between 0.02- 3.0 mradNuclear explosion: nuclear explosion release a lot of energy in form of heat, light, ionizing radiation.
14. MAN MADE SOURCESRadioactive fallout: this includes radioactive substances such as isotopes of carbon, iodine, cesium, strontium. They are considered important because they are liberated in large quantities & remain radioactive for many years.For example, the half life of Strontium is about 28years, the radioactive particles are released into the atmosphere, they float down to earth for some years afterwards and the particles are distributed by air currents fairly evenly over the whole human race.
15. SOURCES OF NON-IONIZING RADIATIONExtremely low frequency (ELF) radiation- at 60HZ, is produced by power lines, electrical wiring, & electrical equipment.Radio frequency- radio and satellite communications, can be absorbed throughout the body.Microwave radiation- sources include cell phone (mobile) telephone, weather radars, airport scanners, microwave oven. Can be absorbed near the skin.Visible light radiation- sunlight, fire, LEDs, light bulbs, lasers.Ultraviolet radiation (UV)- sunlight
16. SOURCES OF NON-IONIZING RADIATION A certain amount of natural radiation from the sun is essential for the absorption of Vitamin D. Intentional exposure such sunbathing must be considered with the us of sun screening lotion with a screening protector factor (SPF) of 30 to reduce he hazardous effect of the sun
17. SOURCES OF NON-IONIZING RADIATION Infrared radiation (IR)- sources include, furnaces, heat lamps, kitchen oven and infrared lasers. The skin & eyes absorb infrared radiation as heat,.Some everyday appliances e.g. TV sets, luminous wristwatches, are radioactive but radiation from these sources are very small to be important.
18. CURRENT TRENDS ON USE OF RADIATIONToday, radiation is a common and valuable tool in medicine, research and industry. It is used in medicine to diagnose illnesses, and in high doses, to treat diseases such as cancer. Also, high doses of radiation are used to kill harmful bacteria in food and to extend the shelf life of fresh produce. Radiation produces heat that is used to generate electricity in nuclear power reactors. Radioactive materials are used in a number of consumer products, such as smoke detectors and exit signs, and for many other research and industrial purposes.Security screening at airports and shipping ports.
19. CURRENT TRENDSThe effect of mobile phone radiation on human health is the subject of recent interest and study, as a result of enormous increase use of mobile phones throughout the world. Mobile phones use electromagnetic radiation in the micro wave range.International Agency for Research on Cancer (IARC) classified mobile phone radiation as Group 2B (Possibly carcinogenic, not Group 2A (Probably carcinogenic ), nor the dangerous Group 1 . This means there could be some risk of carcinogenicity with heavy use of mobile phones. There is a need to conduct more research to confirm the adverse effect of phone use.
20. TYPE OF EXPOSURERadiation exposure may be internal or external, acquired through various exposure pathways.Internal exposure to ionizing radiation occurs when a radionuclide is inhaled, ingested or enters into the bloodstream (e.g. injection, wounds), exposure stops when the radionuclide is eliminated from the body, spontaneously (e.g. through excreta) or as a result of a treatment.
21. TYPE OF EXPOSUREExternal contamination occur when airborne radioactive material (dust, liquid, aerosols) is deposited on skin or clothes, often removed from the body by simply washing. Exposure to ionizing radiation can also result from external irradiation (e.g. medical radiation exposure to X-rays), which stops when the radiation source is shielded or when the person moves outside the radiation field.
22. RADIATION MEASUREMENTThe potency of radiation is measured in 3 ways.Roentgen: this is the amount of radiation that is absorbed in air at a given point. It is the unit of exposure., this means the number of ions produced in 1ml of air.Rad: this is the unit of the absorbed dose. It is the amount of radioactive energy absorbed per gram of tissue or material.Rem: it is the product of the absorbed dose and the modifying factors. The Rem indicates the degree of potential danger to health.
23. HEALTH EFFECTS OF RADIATIONIn many cases, the amount of radiation dose equivalent is much less than one rem. So, a smaller unit, the millirem, is used (1 rem = 1,000 millirem).As radiation moves through matter, some of its energy is absorbed into the material. The amount of radiation energy deposited per unit of mass of matter (tissue) is known as the absorbed dose.When radiation is absorbed by living tissue, the type of radiation, in addition to the absorbed dose, is important in determining the degree of damage that may occur.
24. HEALTH EFFECTS CONTDRadiation dose in medical x-rays. The dose from this source varies with the type of examination Chest x-ray results in a dose equivalent of about 10 millirem Mammogram - 200-300 millirem Abdominal examination - 400 millirem) Computed tomography (CT scan) - 2,000 - 10,000 millirem. Radiation therapy to treat cancer- 5,000,000 millirem (or 5,000 rem) is delivered to the tumor site.
25. HEALTH EFFECTS OF IONIZING RADIATIONThe biologic effect of ionizing radiation is divided into 2Somatic effects: A dose of 400 to 500 roentgens is fatal in about 50% of cases and 600 to 700 in every case. A dose of 25 to 50 roentgens affect white blood cells causing softening of the muscles and lassitude. Delayed effect causes leukemia, malignant tumors and shortening of life.
26. HEALTH EFFECTS OF IONIZING RADIATIONGenetic effects: While somatic effects are seen within the lifespan of the irradiated person, Genetic effects would be manifested in the more or less remote offspring.This is as a result of injury to chromosomes, chromosome mutation and point mutations. With effects such as sterility
27. SUMMARY HEALTH EFFECTS- IONIZING RADIATIONRadiation sickness & acute radiation syndromeCataract &Ocular lesionLeukemia LeucocytopaeniaCarcinogenesis Fetal developmental abnormalitiesFetal death (within 2weeks of conception)Chromosome mutationShortening of life
28. HEALTH EFFECTS CONTDSterility in menMental and growth retardation in childrenSkin erythemaCasualties among miners are as a result of prolonged and intense exposure to uranium which is a radio-active mineral. This may cause skin ulcers, cancer, premature aging, kidney dysfunction and genetic disorders in children
29. HEALTH EFFECTS OF NON-IONIZINGUltraviolet light can cause burns to the skin and cataracts to the eyeUltraviolet light can produce free radicals that induce cellular damage and can be carcinogenicVisible light may cause skin photo-aging, skin burn and also cause retinal injury and cataract to the eye.
30. HEALTH EFFECTS OF NON-IONIZINGMicrowave causes heating of body tissue.Radio-frequency radiation causes heating of body tissue and raised body temperature.Low frequency radiation causes disturbance of nerve and muscle responses.Excessive exposure to infrared radiation inform of heat produces heat sensation & pain.
31. Radiation Control and PreventionThe amount of radiation received from the outer space & background radiation is estimated to be 0.1 rad a year. The additional permissible dose from man made sources should not exceed 5 rad a year. X-ray constitute the greatest hazard.In routine fluoroscopy a dose of 4rad is delivered to a part of the body in one minute.Avoid unnecessary X-ray examinations, most especially children & pregnant mothers
32. Radiation Control and PreventionAdequate control & surveillance of X-ray installationsImprovement in techniques & methods in order to ensure dose reductionProtection of workers through use of PPEs e.g. lead shied & lead rubber aprons. This should be worn by all workers associated with X-ray proceduresProtective clothing's should not be worn in non active rooms.
33. RADIATION CONTROL AND PREVENTIONWearing of film badge or Dosimeter that shows accumulated exposure to radiation by workers on continuous observationSuspension of jobs or given job free from radiation hazard.Periodic medical examinations of workers (skin, nail, blood urine, faeces, sputum)Maintaining workers state of health by ensuring regular working hours, recreation and holidays.Health EducationLegislation /Regulation & enforcementRoutine monitoring
34. RADIATION CONTROL AND PREVENTION Proper management of radioactive waste. Radioactive liquids waste should not be disposed into the river and sewers. Solid waste should be kept separate.Radiation protection is called radiation-hygiene.
35. RADIATION CONTROL AND PREVENTION The International Commission on Radiological Protection (ICRP). The international Atomic Energy Agency (IAEA) and the World Health Organization (WHO) have been active in maintaining radiation hygiene.ICRP recommended that the genetic dose of the whole population from all sources should not exceed 5 rems over a period of 30years.
36. RADONConduct community education regarding the nature and dangers of inhaling radon gas.Ensure sealed basement during construction in order to avoid release of radon into building from underlying soilPerform a periodic check of radon levelsCirculate air with fans in homes Seal cracks in basement floors and wallsRequire building modification where radon concentration is high.
37. PROTECTING THE NURSERadiation injury can occur from overexposure to radioactive materials used in diagnostic & therapeutic procedures. Clients being examined in the above stated procedures are exposed to radiation though minimal, nurses need to protect themselves from radiation, especially when caring for clients on radiation therapy. Exposure to radiation can be minimized byLimiting the time near the sourceProviding as much distance as possible from the sourceUsing shielding devices such as lead aprons when near the source.
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