Radiation Curriculum Table of Contents

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Radiation Curriculum

Table of Contents

I.

Overview

A.

What is Radiation?

B.

Types of Radiation

C.

Chart of Wavelength

D.

X
-
Rays
vs.

Gamma Rays

E.

Units of Measurement for Radiation

F.

Earth’s Orbit and its Effects on Exposure to Radiation

G.

Biological Effects of Radiation


II.

Sources of Exposure to Radiation

A.

Background/Naturally Occurring

B.

Medical Process

C.

Abnormal/Man Made

D.

Prevention


III.

Uses/Effects

A.

Beneficial

Applications of Radiation (Heal
th, Industry,
Etc.)

B.

Hazards of Radiation Exposure


IV.

Model Systems for Studying the Effects o
f Radiation


V.


Statistics Related to Radiation’s Health Effects on Humans








Grade Level:
Middle School (6
th
-
8
th
);
High School (9
th
-
12
th
)

Georgia Standards:
S6E2, S6E6, S7L2, S7L4, S8P4; SCSh9, SP4, SMI5, SEV4, SAP5, SC2, SC3, SAST1,
SAST3

S
cience
E
arth Science Standard;
S
cience
L
ife Science Standard;
S
cience
P
hysics Standard;

S
cience
C
haracteristics of
S
cience
h
igh School Standard
;
S
cience
MI
crobiology Science Standard;
S
cience
E
n
V
ironmental Science Standard;
S
cience Human
A
natomy and
P
hsyiology Science Standard;
S
cience
C
hemistry Science Standard;
S
cience
AST
ronomy Science Standard


Purpose of activity:

Educate students about radiation exposure and links to cancer

and provide them
with the knowledge to make informed decisions that will
reduce their risk

of exposure.

Goals/Objectives:



understand how the Earth's tilt and orbit contribute to energy transfer



understand how cell structure is degraded from abnormal and natural radiation exposure



understand the patterns and characteristic of wa
ves to their contribution toward energy



addresses how various elements and energies affect our environment and health through
different mechanisms which target key organic structures



I.

Overview

A.

What is Radiation?

i.

Radiation is the term for energy that
travels through space, including air,
water, the ground, and outer space. Radiation travels in a path that looks
like a series of waves. Depending on the shape of the waves and the rate at
which the waves are formed, radiation can have different properties
.
Examples of radiation include the light we use to see, heat from the sun
and the signals created and received by cell phones. One way in which
types of radiation differ is in their wavelength. One wavelength is defined
as the distance between the peaks o
f two adjacent waves.

The complete
range of frequencies and energies that characterize different forms of
radiation is called the electromagnetic spectrum. It is comprised of radio
waves, microwaves, infrared light, visible light, ultraviolet light, x
-
rays
,
and gamma rays. The speed, frequency, and energy of each wave type are
used to sort radiation into different categories.

(1)


B.

Types of Radiation

i.

Radiation can be split into two categories, non
-
ionizing radiation and
ionizing radiation.

(2)


1.

Non
-
ionizing
radiation


a.

This type of radiation is common in everyday life and we
are regularly exposed to it. Normal amounts of this type of
radiation are experienced as lower frequency radiation such
as radio waves, infrared, visible, and ultraviolet light.
However, e
xtreme amounts of these non
-
ionizing radiations
can lead to damage in human tissue.



i.

Radio frequency (RF)


Longest wavelength;
typically used for communication, radio or radar
signals


ii.

Microwaves (MW)


Has a slightly shorter
wavelength than radiofrequen
cy; used for radar,
radio transmission, and cooking


iii.

Infrared (IR)


Falls just between microwaves and
visible light on the spectrum; used for heat detection
or remote controlled objects.


iv.

Visible light


This is a small band of color that
human eyes are a
ble to see; this type of radiation is
expressed to us as colors, red, orange, yellow, green,
blue, and violet.


v.

Ultraviolet Radiation (UV)


This form of radiation
comes from the sun as well as other stars, and ravels
to earth though our ozone as high ener
gy. This type
of radiation helps to heat the earth.


2.

Ionizing
Radiation


a.

There are two types of radiation categorized as ionizing
radiation. First, there are electromagnetic waves, these
types of waves have high frequencies, with the ability to
break
chemical bonds in which energy is released,
effectively removing electrons or destroying the nucleus of
the atom. Of the spectrum X
-
rays and Gamma
-
rays are
located in the high frequency range. Exposure to these
types of radiation can lead to severe tissue
damage.

Secondly, there are particles which are comprised of
protons, electrons, and neutrons. These types of ionizing
particles are alpha and beta particles.

(3)


i.

X
-
rays


These are high energy waves, which fall
after UV light on the EM spectrum. These ar
e used
by doctors and scientist of observe internal
structures of the
human body, such as bones, as well
as cosmic gases.


ii.

Gamma
-
rays


These waves have the highest
energy in the EM spectrum. Radiation given off
from an atom undergoing radioactive decay.
Have a
high penetrating power, which can pose external
and internal health hazards, and require lead or steel
to shield the source.


iii.

Alpha particles
-

These particles are identical to the
nucleus of helium atoms (2 protons + 2
neutrons).This type of
radiation has a very short
range and can be shielded with a thin sheet of paper.
They cannot penetrate the first outer layers of skin,
posing no serious external radiation hazards,
however, if inhaled or ingested they can give way to
serious health risks.

(4)


iv.

Beta particles
-

These particles are common
products of the radioactive process of nuclear
fission, they occur naturally in radioactive decay
process, and are comprised mainly of electrons.
Beta particles are less ionizing than alpha particles,
but ca
n travel further and penetrate skin or tissue.
This type of radiation is still hazardous as it can
cause damage to internal organs or living cells.

(4)


C.

Chart of Wavelengths














D.

X
-
Rays vs
.

Gamma Rays


Radiation Type

Wavelength

Extremely Low Frequency

100,000

km


10,000 km

Very Low Frequency

100

km


10km

Radio

10km



1dm

Microwaves

1dm


1mm

Infrared

1mm


.7µm

Visible Light

700nm


400nm


Ultraviolet

400nm


100nm

X
-
rays

10 nm


0.01nm

Gamma rays

0.1nm


0.001nm

i.

Both are classified
as high ionizing radiation; however they differ in how
each is produced. X
-
rays originate from the clashing of electrons onto a
target, or the result of rearrangement. Gamma Rays form as a product of
radioactive decay from nucleus of radionuclide.

(4)


E.

Uni
ts of Measurement for Radiation


i.

There are many different techniques and methods used today for assessing
radiation levels. Surveys and measurements from ground and air can be
taken to find the amount of contamination within the soul and
environment around

us. Using radiochemical methods, samples from the
ground (soil, vegetation, and crops) can be analyzed to determine the type
and amount of radiation present.

(5)

ii.

Units of Measurement

(5)


Type of
Measurement

What is it used
for?

International
System (SI)

Conventional
System (U.S.)

Biological Risk

Measuring the
risk that
someone can
endure from
radiation
exposure

Sievert (Sv)

Rem


100 rem = 1 Sv

Absorbed Dose

Measured by
the amount of
energy
deposited per
weight of
human tissue

Gray (Gy)

Rad


100 rad = 1
Gy

Emitted
Radiation

Measuring
how much
radiation
comes from a
radiation
source

Becquerel (Bq)

Curie (Ci)


1 uCi = 37,000 Bq

F.

Earth’s Orbit and its Effects on Exposure to Radiation

i.

It takes about 24 hours for a complete rotation on its axis and bout 365
days for earth to complete a revolution.


ii.

Earth is closer to the sun in the summer of the southern hemisphere and
winter of the northern hemisphere. During these periods of time, the
Earth’s surface receives more solar energy.

Countries of the middle
latit
udes are exposed to more solar energy in the summer due to the suns
location of being nearly overhead which, in turn, contributes to the longer
duration of the day.
Summer, in these countries, has the longest duration
of sun exposure. The worst times of
day are between 10 a.m. and 4 p.m.



G.

Biological Effects of Radiation

i.

Ultraviolet Radiation


1.

When UV light hits the skin, damage occurs at a molecular level.
The DNA selections that have thymine nucleotides next to each
other undergo a reaction (breaking and forming bonds). The two
thymine pairs for a dimer (two molecules together) which in turn
f
orms a kink in the DNA. This kink can disrupt the replication of
new DNA or produce mutated DNA when copied. When new cells
are made from the mutated copy of DNA, these new cells can be
irregular; many of these together

can produce harmful irregularities
o
n the skin.


(6)
(7)


ii.

Ionizing Radiation


1.

Ionizing radiation can break or form new chemical bonds, such as
double stranded DNA breaks, during which free radicals (highly
reactive molecules) can be formed. This is done through the loss of
electrons from the

molecule as it is “ionized.”
(8)


2.

Collision of ionizing radiation in cells produces hydroxyl radicals

(8)


3.

Stop cell repro
duction, by inhibiting key cell structures (organelles
such as mitochondria)
.

(9)


4.

Cell
death can result from high or frequent
exposure from ionizing
radiation. If cell death is not a result of the mutation caused by
radiation then new mutated cells can be produced uncontrollably
when the cell undergoes mitosis. The results of this cell can be
potentially cancerous.

(9)


II.

Sources o
f Exposure to Radiation


A.

Background/Naturally Occurring

i.

Radon

(10)

1.

This is the largest source of natural radiation exposure to humans

2.

Passes through air space through soil and rock

3.

Pressure differences can move the gas indoors

4.

200 millirems (mrem)
of radon

exposure on average per American


ii.

Isotopes

(11)

1.

Potassium & carbon, the body cannot differentiate between
radioactive & non
-
radioactive particles


iii.

Terrestrial radiation

(11)

1.

Accounts for 8% of radiation (27 mrem) Americans are exposed to,
annually.

2.

High
-
energy particles bombard Earth’s atmosphere as Earth travels
through space.


B.

Medical Process

(11)

i.

Diagnosis

1.

Nuclear tracers (injected into the blood stream)

2.

X
-
rays


ii.

Therapy and Treatments

1.

Cobalt irradiation (a treatment for cancer)

2.

Radiation Therapy


iii.

15% of annual exposure (53 mrem)


C.

Abnormal/Man Made

(11)


i.

Nuclear Power

ii.

Neon signs

iii.

Smoke detectors

iv.

Tanning beds

v.

Air
port scanners

vi.

Gas mantels

vii.

Consumer products

1.

Tobacco

2.

Natural Gas

3.

Phosphate fertilizers

4.

Brick or stone

5.

Ceramics


D.

Prevention


i.

There are three basic strategies to prevent and protect against unnecessary
exposure to radiation:
(12)

1.

Reduce the time you are exposed to
the radiation source; the dose
amount is directly proportional to the amount of exposure time.


2.

Increase the distance

between you
rself and the radiation source;
exposure decreases rapidly as the distance between person and
source increases.


3.

Increase shielding between you
rself and the radiation source;
placing a heavy material between your person and source will
reduce t
he amount of exposure.


ii.

Microwave

Oven:


1.


Microwaves are re
flected, transmitted, or absorbed by material in
their path.”

(13)



2.

Microwave ovens are built to contain these waves within the
device, and generally will not work if the latch isn’t closed.


3.

To prevent unnecessary leaks, insure that the seals remain clean,
there are not visible signs of damage to the outer shell, and that the
manufactures recommendations are followed.


iii.

Ultraviolet Light:

(14)

1.

Limit midday sun exposure by
short time in the sun

2.

Find shade

3.

Wear protective clothing, sunglasses, hats, and sunscreen

4.

Avoid the use of tanning beds

5.

Apply sunscreen frequently


iv.


X
-
rays:

(12)

1.

Never put any part of your body in the expected path of the main
beam.

2.

Avoid being around the X
-
ray
source

as much as possible

3.

Keep the enclosure doors closed whenever possible

4.

When getting medical
X
-
rays protect the parts that aren’t under x
-
ray with a heavy material


III.

Uses/Effects

A.

Beneficial

Applications of Radiation (Heal
th, Industry, Etc.)

i.

Radio Waves

1.

Data
Transmission


ii.

Microwaves

(13)

1.

TV broadcasting

2.

Radar


air & sea navigation

3.

Telecommunications

4.

Processing materials

5.

Diathermy treatment

6.

Cooking Food


iii.

Ultraviolet Radiation

1.

Stimulated Vitamin D production, aids in bone growth with
presence of calcium

2.

Solar

Energy

3.

Treatment of Psoriasis


iv.

X
-
rays

1.

Used in medical field to observe internal structures, such as bones

2.

Used in surgeries for accurate positioning

3.

Diagnostic tool (CT or CAT scans)

4.

Viewing contents of bags in airports


v.

Gamma Radiation

1.

Can be useful
for sterilization of medical equipment as it can kill
all microorganisms present

2.

Gamma
-
rays are effectively
used

as tracers in research sciences

3.

Can be used as gauges for density and thickness monitoring

4.

Used in food preservation to extend self
-
life and p
asteurization

5.

Very portable and require only a small amount of radioactive
material


vi.

Carbon Dating

1.

Used for determination of ages of fossils and other objects, through
analyzing radioactive decay


vii.

Radiotherapy

(15)

1.

Kills cancerous cells to cure cancer or
alleviate symptoms

2.

Designed to maximize the relief and effectiveness while
minimizing side
-
effects.


viii.

Radioactive material

(11)

1.

Smoke Detectors

used Americium
-
241 to detect smoke particles in
the air.

2.

Sterilize products (cosmetics and medical supplies)

3.

Shrink
-
wrap packaging


B.

Hazards of Radiation Exposure

i.

Radioactive
Iodine

(16)

1.

I
odine concentrates in the thyroid, body cannot tell difference
between radioact
ive iodine and non
-
radioactive.

2.

Radioactive iodine can induce mutations leading to thyroid cancer.


ii.

Radon

(17)

1.

S
ettles in low spaces,

such as basements and passes through
crevasse easily.

2.

C
oncentrates in the lungs and induces mutations which can cause
lung
-
cancer.


iii.

Other radioactive material such as strontium and radium can accumulate in
the bone
tissue, leading to cancer.

(18)


iv.

Ionizing Radiation

1.

Increased breast cancer risk has been seen in young women
exposed to high cumulative doses of x
-
ray exposure (
19
)

2.

Leukemia and lung cancer seem more likely than other types of
cancer to be produced by rad
iation

(20)

3.

At a more molecular level, ionizing radiation can induce damage in
DNA, gene expression, mobilization of repair proteins, activation
of cytokines, and disrupt remodeling of cellular microenvironment.
(21)


v.

Nuclear fallout from events such as the Chernobyl nuclear reactor
meltdown
(2
3
)

and the incidents tha
t took place in Japan during WWII

lead to environmental changes:

1.

Soil contamination

2.

Crop contamination

3.

Water contamination


vi.

Radiation is also a known carci
nogen that can cause teratogen mutations,
these mutations are induced by agents that disrupt the development of
embryos and fetuses and can result in birth defects.


vii.

Mild exposure of radiation and cause acute radiation sickness, effects and
symptoms includ
e: (18)

1.

Blood chemistry changes

2.

Nausea

3.

Fatigue

4.

Vomiting

5.

Hair loss

6.

Diarrhea

7.

Hemorrhages

8.

Internal Bleeding

9.

Damage to the central nervous system

10.

Loss of consciousness

11.

Death


IV.

Model Systems for Studying the Effects of Radiation

A.

Model systems are great for studying effects of different types of processed.
These systems mimic results that are similarly seen in human models. They are
better for use than humans because these systems grow quickly, are kept easily,
provide sufficient n
umber of offspring and

are relatively cheap to keep. (22)
Some common model systems used are:


i.

Mice

share 99% of genes that humans have. They are easily raised and can
have their DNA altered to express genes have might pose problems in
humans. They are easy to keep and have contributed to many
developments in science.


ii.

Cell l
ines

are a good way to pres
erve a set of cells. These cell lines are
distinct cells grown in culture, normally from a donor. The cells can live
for an extensive amount of time and typically are clones. Cell lines are
great for studying different aspects of illness and disease and ha
ve been
used for many years to help contribute to biological developments and
applications.


V.


Statistics Related to Radiation’s Health Effects on Humans

A.

The average annual radiation dose that Americans receive is around 400 millirems
(mrems).

i.

50% of the population would die within 30 days of receiving a dose
between 350,000 to 500,00 mrem.
(2
4
)


ii.

E
xposure comes from a variety of sources: (11)

1.

Radon


200mrem (55%)

2.

Inside Human Body


40mrem (11%)

3.

Rocks & Soil


28mrem (8%)

4.

Cosmic


27mrem (8%)

5.

Medical/Dental X
-
rays


39mrem (11%)

6.

Nuclear Medicine


14mrem (4%)

7.

Consumer Products


10mrem (3%)

8.

Other Sources (<1%)


B.

Radiation and cancer


i.

Illness

1.

In a group of 10,000 who are exposed to 1 rem of ionizing
radiation (in small doses over a lifetime) 5 or

6 more people to die
of cancer than would otherwise.

(18)


2.

Of this group, 2,000 are expected die of cancer from all non
-
radiation causes.
(18)


3.

50% and 90% of skin cancer are due to UV raduation
. (14)


4.

18 million people worldwide are blind from cataracts,

5% may be
due to UV radiation
. (14)


ii.

Therapy Statistics:


(25)

1.

Patients of breast cancer, prostate cancer, and lung cancer account
for more than half (56%) of all those receiving radiation therapy.

2.

Radiation therapy will be used in almost 2/3 of all
cancer patients
treatments


C.

Historical Data


i.

1986


Chernobyl nuclear reactor incident: 134 people received radiation
doses of 80,000
-
1,600,000 mrem and suffered from acute radiation
sickness; of these 28 died within 3 months of the accident
. (2
4
)


ii.

10 year
s before the Chernobyl incident: In Belarus 1,342 adults and 7
children were diagnosed with thyroid cancers. (2
3
)


iii.

9 years after the Chernobyl incident: In Belarus 4,006 adults and 508
children were diagnosed with thyroid cancers. (2
3
)





VI.

Resources

1.

Electromagnetic Radiation. The Encyclopedia of Earth. Accessed 6 June. 2011
[http://www.eoearth.org]

2.

Safety and Health Topics: Radiation. Occupational Safety & Health
Administration. Accessed 6
-
8 June. 2011 [http://www.osha.gov]

3.

Ionizing Radiation. Argonn
e National Laboratory. Accessed 7
-
9 June. 2011
[http://www.evs.anl.gov]

4.

Radiation Protection. Australian Radiation Protection and Nuclear Safety Agency.
Accessed 9
-
14 June. 2011 [http://www.arpansa.gov.au]

5.

Radiation Basics. Centers for Disease Control and
Prevention. Accessed 13
-
14
June. 2011 [http://www.cdc.gov]

6.

Morgensen, M. and Jemec G.B. “
The potential carcinogenic risk of tanning beds:
clinical guidelines and patient safety advice
.

Cancer Manag Res.
2 (2010):
277

282. [
PUBMED
]

7.

Freeman, S.
Biological Science
. San Francisco, California: Pearson, 2011

8.

Sun, J. “Role of Antioxidant Enzymes on Ionizing Radiation Resistance.” Free
Radical Biology and Medicine 24 (1998):
596
-
593 [
ScienceDirect
]

9.

Martin, L.M. “DNA mismatch repair and the transition to hormone independence
in breast and prostate cancer.” Cancer Treatment Reviews 36 (2010): 518
-
52
7
[
ScienceDirect
]

10.

Radiation Exposure and Cancer. American Cancer Society. Accessed 16
-
22 June.
2011 [http://www.cancer.org]

11.

Appleby, A. “What Are the Sources of Ionizing
Radiation?” The State University
of New Jersey: RUTGERS. (1996)

12.

Research X
-
ray Safety Manual. University of South Florida. 2003
. [
PDF
]

13.

Electromagnetic fields & public health: Microwave ovens
. World Health
Organization. Accessed 22 June. 2011 [http://www.who.int]

14.

Ultraviolet radiation and human health. World Health Organization. Accessed 21.
June 2011. [http://www.who.int]

15.

Medical Uses of Radiation. International Atomic Energy Agency. [
PDF
]

16.

Samet, J.M. “Radiation and cancer risk: a continuing challenge for
epidemiologists.” Environ Health 10 (2011): S4 [
PUBMED
]

17.

Krewski, D. “Residential

Radon and Risk of Lung Cancer: A Combined Analysis
of 7 North American Case
-
Control Studies.” Epidemiology 16 (2005):
137
-
145

[
JSTOR
]

18.

Health Effects | Radiation Protection. Environmental Protection Agency.
Accessed 13
-
18 June. 2011 [http://www.epa.gov]

19.

Little, M.P. “Risk Associated with Low Doses and Low Does Rates of Ionizing
Radiation: Why Linearity May Be (Almost) the Best

We Can Do.” Radiology
(2009): 6
-
12 [
PUBMED
]

20.

Goldman, M. “Ionizing Radiation and Its Risk.” West J Med. 6 (1982): 540
-
547
[
PUBMED
]

21.

Nelson, G.A. “Fundamental Space Radiobiology.” Gravitational and Space
Biology Bulletin 12 (2003): 29
-
36 [
GSB
]

22.

Alberts, B.
Essential Cell Biology
. Garland Science, 2009

23.

“Present and future environmental impact of the Chernobyl accident”
International Atomic Energy Agency. August 2001 [
PDF
]

24.

Fact Sheet on Biological Effects of Radiation. United States Nuclear Regulatory
Commission. Accessed 27 June. 2011 [http://www.nrc.gov]

25.

Statistics: About Radiation Therapy. RT

Answers. Accessed 11 July. 2011
[http://www.rtanswers.org]