1. Radiation Exposure and Health
Energy that travels in the form of waves or high-speed particles
It occurs naturally in sunlight and sound waves
Man-made radiation is used in X-rays, nuclear weapons, nuclear power plants and cancer treatment

2. Radiation And Radioactive Material Is A Part Of Nature
Everything that's living has some amount of radiation coming from it — a very small amount
Plus there's radiation in the ground and the air
Radiation And Radioactive Material Is A Part Of Nature
Bananas have a lot of potassium. And a small amount of potassium naturally is called potassium 40, which is radioactive
Harmful radiation is ionizing radiation
NON-IONIZING radiation includes everything like radio waves and visible light and the microwave

3. THE BIGGEST CHUNK OF IONIZING RADIATION COMES FROM RADON
The everyday exposure to radiation contributes an extremely tiny risk to our life or health compared to all of the other risks encountered in day-to-day life.

4. Prolonged exposure to high levels of radon can lead to lung cancer, which is radon's only known adverse effect
Radon is considered to be the leading cause of lung cancer among nonsmokers in the United States

5. High radon areas in the U. S
High radon areas in the U.S. tend to be in the northern section of the country due to the types of soils found there, (Zone One)
States with high concentrations of radon include Iowa, North Dakota, South Dakota, Maine, Minnesota, Illinois, Kansas, Montana, Idaho, Wyoming, Colorado, Pennsylvania, and Virginia
Moderate radon levels include Alaska, Arizona, Nevada, Missouri, Utah, and Wisconsin. Significant parts of California, Oregon, and most of New England
(Zone Two)

6. Curie (Ci) CU Becquere(Bq) SI Rad Gray (Gy) Rem Sievert (Sv)
Units of Measure
Curie (Ci)
Amount of radiation being given off, or emitted CU
Becquere(Bq) SI
Rad
Radiation dose absorbed by a person
Gray (Gy)
Rem
Biological Risk of exposure
Sievert (Sv)
CU = Conventional Unit (used in the United States)
SI = System Internationale (evolved from the metric system)

7. Measures There are 1,000 millisieverts (msv) in a sievert or
1,000 millirems in a rem
A DOSE OF 400 MILLISIEVERTS IS EQUIVALENT TO THE DOSE FROM CT SCANS

9. Ionizing Radiation Most Common Alpha Beta
A positively charged particle made up of two neutrons and two protons
Can be stopped by thin layers of light materials, such as a sheet of paper, and pose no direct or external radiation threat
Can pose a serious health threat if ingested or inhaled
Beta
An electron or positron emitted by certain radioactive nuclei
Beta particles can be stopped by aluminum
Can be lethal depending on the amount received
Also pose a serious internal radiation threat if inhaled or ingested

10. Gamma
High-energy electromagnetic radiation emitted by certain radio-nuclides when their nuclei transition from a higher to a lower energy state
Rays have high energy and a short wave length
All gamma rays emitted from a given isotope have the same energy
Gamma rays are very similar to x-rays
X-Rays
High-energy electromagnetic radiation emitted by atoms when electrons fall from a higher energy shell to a lower energy shell

12. KINDS OF HEALTH EFFECTS
The amount and duration of radiation exposure affects the severity or type of health effect
Two Broad Categories
Stochastic:
Associated with long-term exposure
Low-level (chronic)
Increased levels of exposure make these health effects more likely to occur but do not influence the type or severity of the effect
Cancer, changes in DNA
Changes in DNA are called mutations
Teratogenic mutations are caused by exposure of the fetus in the uterus
Genetic mutations are passed on to offspring

13. Non-stochastic: become more severe as the exposure increases
Cases of exposure to high levels of radiation
become more severe as the exposure increases
Short-term, high-level exposure is referred to as
'acute‘ exposure include burns and radiation sickness

14. RADIATION SICKNESS “radiation poisoning”
Can cause premature aging and death
If the dose is fatal, death usually occurs within two months
The symptoms of radiation sickness include:
Nausea
Weakness
Hair loss
Skin burns
Diminished organ function
People exposed to high levels of radiation are also at greatest risk of infection, so they need to be kept in isolation wards in sterile environments to protect them from bacteria and viruses

15. IS ANY AMOUNT OF RADIATION SAFE?
EPA makes the conservative (cautious) assumption that any increase in radiation exposure is accompanied by an increased risk of stochastic effects.

16. CHILDREN AND RADIATION
More sensitive to radiation than adults
More cells dividing and a greater opportunity for radiation to disrupt the process
Fetuses are also highly sensitive to radiation

17. Specific Organ Effects
Thyroid Gland
Radioactive Iodine concentrates in the Thyroid
Thyroid needs iodine to function normally
Cannot tell the difference between stable and radioactive isotopes
Radioactive iodine contributes to thyroid cancer more than other types of cancer

18. The substance saturates the thyroid gland with non-radioactive iodine, reducing how much dangerous radioiodine the gland can absorb

19. Bones and Teeth
Calcium, strontium-90 and radium-226 have similar chemical properties
Strontium and Radium in the body tend to collect in these calcium rich areas
They contribute to bone
cancer

20. Teratogenic Mutations Exposure of Fetuses
Smaller head or brain size
Poorly formed eyes
Abnormally slow growth
Mental retardation
Genetic effects
About fifty severe hereditary effects will occur in a group of one million live-born children whose parents were both exposed to one rem. About one hundred twenty severe hereditary effects would occur in all descendants.

21. External particles of radioactive material can be washed away
Exposure Treatment
External particles of radioactive material can be washed away
If the thyroid is contaminated, it can be treated with potassium iodide, which counters some of radiation's effects
Drugs are available that increase white blood-cell production to counter any damage that may have occurred to the bone marrow, and to reduce the risk of further infections due to immune-system damage.
There are also specific drugs that can help to reduce the damage to internal organs caused by radioactive particles

22. Can Radioactive Particles Be Transmitted From Person To Person
YES, IN TWO WAYS
Material that attaches to dust or other small particles and settles on skin or clothing can be transferred during physical contact
An individual who is internally contaminated
can emit particles in urine, blood or sweat,
and coming into contact with these fluids
can transmit exposure.

23. EPA EXPOSURE LIMITS About 100 mrem per year from all sources
In the U.S., the Nuclear Regulatory Commission restricts workers to 50 millisieverts of radiation exposure per year
Staying indoors and sealing your house is a way to prevent ingesting or carrying around any radioactive material
Because iodine has a half-life of just over a week, any grasses, crops or animals exposed to it should be cleared of any residual material in a matter of weeks
The pathway for radioactive iodine to get into
human beings is via milk. The iodine hits the
ground, gets on the grass, cows eat the grass,
and it is concentrated in the milk, and people
drink the milk."

24. References http://www.epa.gov/rpdweb00/understand/health_effects.html

25. Radiation may be absorbed by the medium it passes through.
Radiation can kill living cells or change the nature of living cells.
All living things contain living cells. We have many different types of cells which perform different functions including:
Skin cells.
Red blood cells (they transport oxygen around the body)
White blood cells (they fight infection).
Nerve cells.
Muscle cells.
Brain cells.

26. The Effects of Ionising Radiation
Ionising radiation can kill or change the nature of living cells.
The effects of the damage inflicted by the ionising radiation may:
be severe and cause immediate effects, or
not become apparent for a long time.
The biological effect of radiation depends on:
The type of radiation.
The type of body tissue or body organ that absorbs the radiation.
The total amount of energy absorbed.

27. Short-Term Effects of Radiation
Short-term effects usually occur when there’s a large amount of exposure to radiation.

28. WW2 – Hiroshima and Nagasaki
During the Second World War, two atomic bombs were dropped on Hiroshima and Nagasaki in Japan.
Those people who survived the blast were exposed to a large dose of radiation. Such doses caused severe damage to cells all over the body, especially in the skin, blood, bone tissue and gut.
Many of these people died within a few weeks. Those people who were exposed to a smaller dose recovered from such immediate effects.

29. Chernobyl Nuclear Power Station
There was also a huge nuclear accident at the Chernobyl Nuclear Power station in the former USSR in 1986.
Workers there were carrying out experiments on the reactor rods which caused fires to start. A number of firemen were exposed to very large amounts of radiation and 30 people died as a result.
The damage to the power station was extensive but the radiation effects over a wide area were considerable.

30. Chernobyl Nuclear Power Station
people were removed from an area within a radius of 30 km.
The smoke and radioactive debris reached a height of 1200 m and travelled across Russia, Poland and Scandinavia.
A cloud of material from the accident reached the UK and, with heavy rain, there was material deposited on parts of north Wales, Cumbria and Scotland. This caused certain farm animals (e.g. lambs) to be banned from sale as they had absorbed radiation from the grass.

31. Long-Term Effects of Radiation
These effects take longer to become apparent and can be caused by much lower levels of radiation.
One of the most important long-term effects of radiation is that of cancer in various parts of the body.
Uranium miners tended to get lung cancer due to breathing in gases which emitted alpha particles.
People who painted the dials of clocks with luminous paint developed one cancer from using their lips to make points on the brushes.

32. Exposure to ionising radiation does not necessarily cause cancer
The mechanisms for cancer occurring are poorly understood at the moment. One theory is that the ionising radiation affects the DNA material within us – our genetic make-up. Our DNA contains genetic instructions which control the operation and reproduction of the cells. If ionisations caused by ionising radiations alter these instructions in the DNA, there is a chance that cancer will develop.
Genetic damage can be caused to cells by radiation, including cells which are involved in reproduction.

33. Quality Factor
Different types of radiation have different effects on living cells.
Even though the same type of tissue may receive the same dose, the biological effects of different radiations will be different. To take this into account, a quality factor is assigned to all types of radiation.
The quality factor, Q, allows the effects that different radiations have on living cells to be compared.

34. Quality Factor Radiation Quality Factor (Q) Alpha particles 20
The quality factor for each type of radiation is shown below:
Radiation
Quality Factor (Q)
Alpha particles 20
Beta particles 1
Gamma rays
From this it can be seen that alpha radiation is the most ionising radiation out of the three types.

35. Dose Equivalent
REMEMBER, the biological effect of radiation depends on:
The type of radiation.
The type of body tissue or body organ that absorbs the radiation.
The total amount of energy absorbed.
The DOSE EQUIVALENT is a measure of the biological effect of radiation and it takes account of the type and energy of the radiation as well as how the radiation is distributed.

36. The DOSE EQUIVALENT is measured in sieverts (Sv).
Because 1 Sv is a very large dose of radiation which could only happen as a result of a very serious nuclear accident or explosion, doses are given in millisieverts (mSv) or microsieverts ( Sv).

37. Suppose that 100 people all receive a dose equivalent of 1 Sv spread over the whole body. It is estimated that, of the 100 people on average 4 of them would eventually die as a result of the radiation.
But precisely who would die, or when they would die, or what illness they would die of, cannot be predicted.

38. Background Radiation Radiation is all around us!
Background radiation is radiation that is naturally occurring.

39. Natural Sources of Radiation
Annual Dose (Sv)
Radon and thoron gas from rocks and soil
800
Gamma rays from ground
400
Carbon and potassium in your body
370
Cosmic rays at ground level
300
Total =
1870

40. Man-Made Sources of Radiation
Annual Dose (Sv)
Medical uses – x-rays, etc.
250
Chernobyl (first year) 50
Fall-out from weapons testing 10
Job (average) 5
Nuclear industry (e.g. waste) 2
Others (TV, aeroplane trips, etc.) 11
Total =
328

41. Death Risk - Cause Death Risk - Cause Death Risk – 40 Year Old
All causes
1 per 500
Smoker – 10 per day
1 per 2000
Road accidents
1 per 5000
Home accidents
1 per
Work accidents
1 per
All radiations
1 per
Medical Radiations
1 per

42. Effects of Radiation Somatic Damage Genetic Damage
ryday/
Somatic Damage
Damage to the organism itself
Genetic Damage
Damage to an organisms gene that would affect future generations.

43. Radiation Causes Ionizations of:
ATOMS
which may affect
MOLECULES
CELLS
TISSUES
ORGANS
THE WHOLE BODY

45. Direct Effect
Damage to DNA from ionization.

46. Indirect Effect
Radiation interacting with the water in a cell, rather then the DNA.
Could lead to the braking of bonds in the water molecule that could lead to toxic substances.

47. Ionizing radiation induces direct DNA damage and indirect damage through the radiolysis of water.
Morgan W F , Sowa M B PNAS 2005;102:
©2005 by National Academy of Sciences

49. Effects of Short-Term Exposure
rem – a unit invented to indicate the danger radiation poses to humans.
Dose (rem)
Clinical Effect
0-25
Nondetectable
25-50
Temporary decrease in white blood cell counts
Strong decrease in white blood cell counts
500
Death of half the exposed population within 30 days after exposure.

50. radiation absorbed dose
High Dose Effects
Dose (Rad)
radiation absorbed dose
Effect Observed
15-20
Blood count changes in a group of people. 50
Blood count changes in an individual.
100
Vomiting (threshold)
150
Death (threshold)
LD 50/60 with minimal care
LD 50/60 with supportive medical care
1,100
LD 50/60 with intensive medical care (bone marrow transplant)

52. More than 2,000 rad: Death is a certainty
More than 2,000 rad: Death is a certainty. At doses above 5,000 rad, the central nervous system (brain and muscles) can no longer control the body functions, including breathing and blood circulation. Everything happens very quickly. Death occurs within days or hours. Nothing can be done, and medical care is for comfort only. 1,000 to 2,000 rad: The probability of death increases to 100% within one to two 2000 rad weeks. The initial symptoms appear immediately. A few days later, things get very bad, very quickly since the gastrointestinal system is destroyed. Once the GI system ceases to function, nothing can be done, and medical care is for comfort only to 1,100 rad: Severe blood changes will be noted and symptoms appear immediately. Approximately two weeks later, some of those exposed may die. At rad, up to one half of the people exposed will die within 30 days without intensive medical attention. Death is due to the destruction of the blood forming organs. Without white blood cells, infection is likely. At the lower end of the dose range, isolation, antibiotics, and transfusions may provide the bone marrow with time to generate new blood cells, and full recovery is possible. At the upper end of the dose range, a bone marrow transplant may be required to produce new blood cells to 150 rad: Slight blood changes including temporary drop in production of new blood cells will be noted and likely symptoms of nausea, fatigue and vomiting for one or two days. 5 to 50 rad: Slight blood changes may be detected by medical evaluation Less than 5 rad: No immediate observable effects

54. Environmental Sources
Exposure Source
Millirems
Natural:
Radon
Other
200
100
Occupational
0.90
Nuclear Fuel Cycle
0.05
Consumer Products
5-13
Environmental Sources
0.06
Medical:
Diagnostic X-rays
Nuclear Medicine 39 14
Approximate Total
360

55. Industry
Used to measure the thickness of materials and to detect defects in metals and materials.
Power space craft.
Clean toxic pollutants.
Improve food production.

56. Everyday Uses Smoke Detectors Nonstick pans
Rely on tiny radioactive source to sound the alarm when it sense smoke form a fire.
Nonstick pans
Treated with radiation to ensure that the coating sticks to the surface.

57. Everyday Uses Watches and Clocks Ceramics Glassware
Modern watches and clocks sometimes use a small quantity of hydrogen-3 (tritium) or promethium-147 as a source of light. Older (for example, pre-1970) watches and clocks used radium-226 as a source of light.
Ceramics
Ceramic materials (for example, tiles, pottery) often contain elevated levels of naturally occurring uranium, thorium, and/or potassium.
Glassware
Antique glassware with a yellow or greenish
color, can contain easily detectable quantities
of uranium.
Cosmetics, Hair Products, Contact Lenses
Sterilized with radiation to remove irritants and allergens.

58. Everyday Uses Gas Lantern Mantles Antique Radioactive Curative Claims
While it is less common than it once was, some brands of gas lantern mantles incorporate thorium-232.
Antique Radioactive Curative Claims
In the past, primarily 1920 through 1950, a wide range of radioactive products were sold as cure-alls.
For example, radium-containing
pills, pads, solutions, and devices
designed to add radon to drinking
water.

59. Food Irradiation
Food irradiation is a method of treating food in order to make it safer to eat and have a longer shelf life.

60. Medical Uses

61. Nuclear Power
Nuclear reactors are devices that control fission reactions producing new substances and energy.
Steam is created
from the heat
(energy) produced.
The steam turns
the turbines to
produce electric
energy.

62. A Fission Reactor

63. Figure 19.7: Schematic of the reactor core.
Copyright © Houghton Mifflin Company

64. Nuclear Power
Advantages
Nuclear power costs about the same as coal, so it's not expensive to make.
Does not produce smoke or carbon dioxide, so it does not contribute to the greenhouse effect.
Produces huge amounts of energy from small amounts of fuel.
Produces small amounts of waste.
Nuclear power is reliable.
Disadvantages
Although not much waste is produced, it is very, very dangerous.
The waste must be sealed up and buried for many years to allow the radioactivity to die away.
Nuclear power is reliable, but a lot of money has to be spent on safety - if it does go wrong, a nuclear accident can be a major disaster.
people are increasingly concerned about this - in the 1990's nuclear power was the fastest-growing source of power in much of the world. Now, in 2005 it's the second slowest-growing.

65. Weapons
A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion.