Radiation. Radiation Scare Atomic Bomb - Hiroshima Aug. 6,1945 Nagasaki Aug. 9, 1945 Three Mile...

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Radiation

Radiation Scare

• Atomic Bomb - Hiroshima Aug. 6,1945 Nagasaki Aug. 9, 1945

• Three Mile Island - 1979

• Chernobyl - 1986

Radiation - Positive Uses

• Medical Diagnosis

• Medical Treatment

• Food Irradiation

• Mail Irradiation

• Energy

• Defense

• Industrial

Nuclear Scientist• Ernest Rutherford• Wilhelm Roentgen• Henri Becquerel• Pierre & Marie Curie• Niels Bohr• Max Planck• James Chadwick• Otto Hahn

Einstein’s Formula

E=MC2

Atomic Scientist

Manhattan Project• J. Robert Oppenheimer

• General Leslie R. Graves

• Edward Teller, Luis Alvarez, Eugene Wigner, Maurice Wilkins, etc, etc

• Los Alamos - 1943

• 2 billion cost

• 125,000 people involved

Atomic Bomb• August 2, 1939 - Einstein’s letter to FDR

warning about Germany’s effort to purify U-235

• Manhattan Project 1939 - 1945• July 16, 1945 first bomb exploded - Gadget

Los Alamos NM• August 6, 1945 Hiroshima• August 9, 1945 Nagasaki

Hiroshima• August 6, 1945 dropped from Enola Gay• “Little Boy” 4&1/2 tons• 10 kiloton• 66,000 killed 69,000 injured• Total vaporization one half mile• Total destruction one mile• Everything burned 2 1/2 miles

Nagasaki• August 9, 1945

• Plutonium bomb - “Fat Man”

• 10 kilotons

• 39,000 killed 25,000 injured• Used only 1/10 of 1 percent of

explosive capability

Atomic Bomb Effects

• Blast - speed of sound 12.5 miles/min

• Heat - fireball vaporizes, inverse square law

• Radiation - prompt, inverse square law

• Radiation - fallout

Fallout Products

• Iodine-131

• Strontium-90

• Cesium-137

• Over 200 radioactive products

Byproducts of A-Bomb

• Radioactive fallout for miles in rain• Radiation poisoning• Increased incidence of cancer - leukemia• Genetics effects on future generations• Massive disruption of communications, travel

and machinery• Electro - Magnetic pulse scrambles

electronics in copper wires - 50 miles

Blast Effects20 Megatons

• Vaporization 8.75• Total Destruction 14• Severe Blast Damage 27• Severe Heat Damage 31• Severe Fire, Wind 35

Blast Effects 20 Megatons

• Vaporization 8.75• Total Destruction 14• Severe Blast Damage 27• Severe Heat Damage 31• Severe Fire , Wind 35

Dirty Bomb• Uses conventional explosives

• Radioactive material inside

• Most likely radioactive material is Cesium-137 Half life 30years

• Creates more terror, havoc and panic rather than immediately kill

Radiation Units• R - Roentgen amount of ionization in air

• Rad - radiation absorbed dose

• Rem - radiation equivalent man

• Sievert (Sv) - international unit of radiation equivalency

• Gray (Gy) - unit for energy absorbed

• 1Gy = 1Sv = 100 rad = 100 rem

Curie & Becquerel (Bq)

• 1 Bq is 1 disintegration/sec

• 1 curie = 37 Billion Bq 3.7X10x10

• 1 MBq = 27 microcuries

• 1 GBq = 27 millicuries

• 37 GBq = 1curies

• 1 TBq = 27 curies

Multiple Prefix Symbol 1012 tera T 109 giga G 106 mega M 103 kilo k 10-2 centi c 10-3 milli m 10-6 micro µ 10-9 nano n

Background Radiation Sources

• Earth - food and water

• Space - cosmic rays

• Atmosphere - Radon gas from earth’s crust

Airport X-Ray Security Scanners

• Backscatter superficial scanning

• Dose - 0.1 microsevert

• Would need to go through the scanner 1000X times to equql a chest X-ray or 200,000 times to equal a CT scan

• Scan daily for your entire life wouldn’t equal a CT scan

Types of Radiation

• Alpha Particles

• Beta Particles

• Gamma & X-Rays

Exposure Pathways

• Inhalation

• Ingestion

• Direct (external) Exposure

Radiation Exposure

• Acute Effects

• Cancer Risk

• Genetic Risks

• Teratogenic Risks

Radiation Dose - very serious

4 Sievert (Sv) or 400 rad

total body exposure

Radiation Conversions

• 100 rem = 1 sv (sievert)

• 1 mrem = .01 msv

Acute Effects of Radiation

Condition Mrem Rem Sv

Noobserverableeffect

5,000 5 0.05

Bloodabnormalities

15,000 15 0.15

Spermabnormalities

15,000 15 0.15

Acute Effects of Radiation

Condition mrem rem Sv

NausaAnorexia

100,000 100 1.00

BoneMarrow

200,000 200 2.00

Epilation 300,000 300 3.00

Erythema 600,000 600 6.00

Long Term Effects Radiation

Effect mrem Rem Sv

FetalAbnormalities

10,000 10 0.10

Cancer 10,000 10 0.10

Genetic 25.000 25 0.25

Long Term Effects Radiation

Effect mrem rem Sv

CancerDeath Risk5%

100,000 100 1.00

GeneticRisk 1%

100,000 100 1.00

Cataracts10%

250,000 250 2.50

Typical Medical DosesMedical

X-Ray

mrem mSV

Chest 4 - 5 .04

Cervical Spine

11 .11

Pelvis 27 .27

Typical Medical Doses

MedicalX-Ray

mrem mSv

Upper GI 117 1.17

BariumEnema

298 2.98

CAT Scan 1800 18.00

Environmental DosesSource mrem mSv

NaturalBackground

100 1.00

RadonInhalation

200 2.00

Television 1 0.01

Air FlightNY - LA

4 0.04

Environmental DosesSources mrem mSv

50 miles ofnuclear plant

Less than 1 Less than0.01

ChernobylAverage

1,500 15.00

TMIAverage

2 0.02

Yearly Dose Examples

• Living next to nuclear power plant: .0001-.01 mvs

• Sleeping next to a human being 8hrs/night: .02mvs

• Radiation in granite in US Capitol: .85mvs

• NY to Tokyo flights for airline crew: 9msv/yr.

Yearly Dose Examples

• Background Radiation in US - 3 msv

• Average Radiation Dose for Americans 6.2 msv

Radiation Dose Reduction

• Time

• Distance

• Shielding

Healthcare Facts

• 2.3 Trillion per year

• 8,000 dollars per person

• 13,000 per person by 2013

• 800 billion of the 2.3 Trillion is for Imaging, largest share of healthcare cost

Imaging Facts

• 64 Million CT scans/yr

• 20 Million CT scans probably unnecessary

• 24 Million MR scans

• 1.5 million PET scans, 60% increase

• 800 billion of 2.3 Trillion in Healthcare Cost

ED - Children CT Scans

• 1995 - 330,000

• 2008 - 1.6 Million

Typical Medical Doses

MedicalX-Ray

mrem mSv

Chest 4 - 5 .4

Cervical Spine 11 .11

Pelvis 27 .27

Radiation Dose & Effects

• 10,000 mSv

• 1,000 mSv• 100 - 1000 mSv • 50 mSv

• Radiation Sickness & Death

• Radiation Sickness, Death Unlikely

• Increased risk of carcinogenesis

• Associated with increased cancer risk, MPD worker

Radiation Dose

• Chest X-Ray• Chest CT• Cardiac CT• Renal Stone CT• Abd, Pelvis, CT• Body PET/CT

• .04 mSv• 8 mSv• 8 - 10 mSv• 10 mSv• 10 mSv• 20 mSv