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1. Radio activity and Its Biological EffectsPresented By,Lakshmi DM.Sc., PhysicsAvinashilingam University for Women,Coimbatore, Tamilnadu. www.powerpointpresentationon.blogspot.com

2. Topics to be discussed……. • Radiation • Radio active waste • Biological effects • On animals • On plants • On humans • Preventive measures of radiation

3. What is Radiation? “Invisible energy waves or particles” What is Radioactivity? The radioactivity is the property of some atoms to spontaneously give off energy as particles or rays. The atoms that make up the radioactive materials are the source of radiation.

4. Nuclear Pollution and Waste

5. INTRODUCTION • Radioactive waste is a material deemed no longer useful that has been contaminated by or contains radio nuclides. • Radio nuclides are unstable atoms of an element that decay, or disintegrate spontaneously, emitting energy in the form of radiation. • Releases of radio nuclides to the surrounding environment in liquid and gaseous forms.

6. Ionizing and Non-ionizing radiation? • Radiation carries a range of energy forming an electromagnetic spectrum. • Radiation that does not have enough energy to break chemical bonds but can vibrate atom is referred to as “Non-ionizing Radiations” e.g. radio waves, microwaves, infrared, visible light etc. • Radiation that has enough energy to break chemical bonds is referred to as 'ionizing radiation, e.g. alpha particles, beta particles, gamma rays etc.

7. The potential biological effects and damages caused by radiation depend on the conditions of the radiation exposure. • It is determined by: • quality of radiation • quantity of radiation • received dose of radiation • exposure conditions (spatial distribution) • Particles with high energy loss effects cause typically greater damage. • Radiation can cause immediate effects (radiation sickness), but also long term effects which may occur many years (cancer) or several generations later (genetic effects). • Biological effects of radiation result from both direct and indirect action of radiation.

8. Effects on Plants • Green plants are extremely sensitive to gamma rays. • Higher plants have more radio sensitivity than lower plants. • Plants response varies according to age, growth stage, plant species, chromosome volume and level of radiation. • Degree of damage ∞intensity and duration of exposure of radiation.

9. Causes • Changes in morphological, cellular and genetic levels. • Alterations in plant’s vascular system, water transportation and other functions also affected. • More causes are • Retarded growth, decreased percent germination. • Gigantism, dwarfism, curly and misshaped leaves. • Negative effects on Seeds.

10. Radiation gives positive results also.. • In crop improvement protocols • High disease resistance, vigor and high productivity. • But high dosage may kill the plants.. • It mutate the DNA even in room temperature. • In a food chain, radiation may affect primary and secondary consumers also.

11. Effects on Animals.. • It may include tumor, dry, itchy skin, hair loss and discoloration of the skin around the tumor site. • In addition, these particular tumors often release a disagreeable odor as the cancerous cells die. • More serious side effects may include some nerve damage and either the death or hardening (called fibrosis) of healthy tissue.

12. Radiation on human body

13. Effects on Humans… • Initial signs include, • Nausea, vomiting, headache , some loss of white blood cells • Doses of 300 rems or more cause temporary hair loss, but also more significant internal harm, including damage to nerve cells and the cells that line the digestive tract. • Besides the symptoms, these people also suffer from fever and diarrhea. If no effective treatment is given, death occurs within two to fourteen days.

14. For survivors, diseases such as leukemia, lung cancer, thyroid cancer, breast cancer, and cancers of other organs can appear due to the radiation received. • But Exposure to ionising radiation does not necessarily cause cancer

15. Effects on Humans… • Because man's body contains a lot of water, gamma rays traverse through water (H2O) molecules. Ionization of water usually results in the formation of hydrogen peroxide (H2O2). These molecules can attack a biomolecule and 'denature' (= kill) it. • Radioactive lead, retains the ability to cause brain damage and plutonium clumps on the surface of bone, delivering a concentrated dose of alpha radiation to surrounding cells.

16. Effects on Humans… • It also affects thyroid glands . • It causes the person to have increased pulse rate, nervousness, excitability, loss of body weight and, in females, more frequent c. • If radioactive iodine (I 131 or I 129) is ingested with food it will enter the blood and tend to accumulate in the thyroid. • A small amount of radioactive iodine would probably kill only a few cells and have little or no noticeable effect on health.

17. Preventive measures and considerations…. • Site selection for nuclear power plants should be carefully made to avoid, or minimize to the extent possible, most of those impacts. • The safe management of radioactive waste is necessary to protect public health. • If handled improperly, potential exposures of humans to high-level radioactive waste can be dangerous, even deadly.

18. Things To follow…. • Regulation of Radiation Usage • Proper disposal • Minimizing the usage • Wearing protective clothes • Control on these in radiated area.. • Inhalation • Absorption • Injection without sterilization

19. And it is our duty to save our future generations as healthy human beings…..

20. Conclusion • For Radiation, like other aspects of nuclear science, can be both destructive and beneficial. • The intelligent use of radiation for the treatment of cancer, medical diagnosis, food preservation, and other useful applications requires an informed public. • Likewise, the solutions to the storage of nuclear waste also necessitate public understanding of the effects of nuclear radiation.