Radiation in Everyday Life

clappergappawpawUrban and Civil

Nov 16, 2013 (3 years and 6 months ago)

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Radiation in Everyday Life

Teo Jim Yang 3O3(26)

Contents


Basics


Definition


Ionizing and Non
-
ionizing radiation


Electromagnetic Radiation


Natural Background Radiation


Man
-
Made Radiation


Radiation in Our Environment


Effects of Radiation


Sources of radiation in everyday life


Significance of Radiation Exposure


People who are at higher risk


Radiation Protection

What is radiation?


Energy that travels through space in
the from of particles or waves


Two different types of radiation:
ionizing and non
-
ionizing


Radiation can be found all around us

Ionizing and Non
-
ionizing Radiation

Ionizing Radiation


Has a lot of energy that
gives it the ability to
cause changes in
atoms


Enough to damage DNA


Overexposure can
cause:


Mutations in your genes,
which causes birth
defects,


Raised risk of cancer,
burns


Radiation sickness

Non
-
ionizing Radiation


Relatively low
-
energy

radiation that doesn't
have enough energy
to ionize atoms or
molecules


Although considered
less dangerous than
ionizing radiation,
overexposure to non
-
ionizing radiation can
cause health issues

Ionizing and Non
-
Ionizing Radiation

Summary of Radiation

Natural Background Radiation


Refers to the naturally derived, widespread
radiation present everywhere in the environment


Usually not detrimental to life


3 Main sources:


Cosmic Radiation


Cosmic rays from outer space which bombard the earth


Terrestrial Radiation


Radioactive substances in the earth's crust


Soil


Water


Vegetation


Emanation of radioactive gas from the earth (radon gas)


Internal Radiation


Trace amounts of radioactivity in the body

Man
-
Made Radiation


Two distinct groups of people exposed
to man
-
made radiation sources:


Members of the public


Occupationally exposed individuals

Man
-
Made radiation


Sources that results in exposure to public:


Tobacco (thorium)


Television (EM radiation)


Medical Procedures


Diagnostic X
-
rays


Nuclear medicine


Smoke detectors (Americium)


Building materials (Radon)


Occupational sources


Radiography


X
-
ray technicians


Workers in Nuclear power plant


Nuclear medicine technicians


Light is made up of different components:


Gamma Rays


X
-
Rays


Ultraviolet Rays


Visible Light


Infrared Rays


Microwaves


Radio Waves


They make up the
electromagnetic spectrum


They emit radiation

Electromagnetic (EM) Radiation

Decreasing
in
Wavelength

Decreasing
in
Wavelength

Effects Of Radiation


"Harmful Effects of Radiation" Video



Increased blood pressure


Lesions


Damage to foetus (in pregnant women)


Mental retardation


Miscarriage


Cancers:


Salivary gland cancer


Lymphatic cancer


Bone marrow cancer (leukemia)


Brain cancer


Breast cancer


Heart Disease


Headaches

And much more…

Effects of Radiation

Why does radiation cause harm?


DNA Damage


Our cells have mechanisms to repair DNA damage to a
limited extent but radiation can overwhelm these
mechanisms.


Damaged DNA is implicated in several disease processes,
including various types of cancer.


Interference with Melatonin production


Low melatonin levels have already been linked to several
diseases, including cancers


Interference with Cellular Communication


Our body cells communicate internally and externally by
means of electrical signals.



These signals can be altered by EMF radiation which
generates electrical currents within the body causing
changes in both cellular activity and cellular structures

Effects of Radiation

Factors affecting the effect of radiation:


Intensity of radiation


Exposure to strong radiation may cause damage, even
though the exposure is of short duration


Cumulative Exposure


The combination of the different frequencies a person is
exposed to may overwhelm the body defenses and repair
mechanisms.


Duration of Exposure


Many studies have indicated that various health effects
are only noticed after many years of exposure
to

electromagnetic pollution, for example high voltage
power lines, or cell phones.



Radiation Transience


More biologically stressful to be exposed to fluctuating
radiation which arises from an electrical appliance which
cycles on and off than from a similar appliance that
remains steadily on all day.



Sources of Radiation in Everyday
Life

1.
Cell
-
phones

2.
Tobacco Smoke from smoking

3.
Medical Use of Radiation

4.
Radiation from Appliances

I.
Televisions and Computers

II.
Microwave Ovens

III.
Heating Appliances

IV.
Personal Grooming Appliances

1
. Cell Phone Radiation


Radiation in cell
phones is generated in
the transmitter and
emitted through the
antenna


In the form of radio
waves


These waves
picked up
by a receiver in the cell
-
phone tower

1. Cell Phone Radiation


When talking on a cell phone, most users place the
phone against the head


Some of the radiation might be absorbed by human tissue


Radio frequency (RF) radiation has the ability to
heat human tissue


Damage to tissue can be caused by exposure to RF
radiation because the body is not equipped to dissipate
excessive amounts of heat


The eyes are particularly vulnerable due to the lack of
blood flow in that area


Use of cell phones may have potential links to:


Cancer


Brain tumors


Alzheimer's disease


Parkinson's disease


Headaches

1. Cell Phone Radiation


Some precautions that can be made
to reduce RF radiation exposure from
cell phones:


Extend the antenna during use


Use a phone that places the antenna as
far away from you as possible


Use a hands
-
free headset


Limit calls inside buildings


Use the phone in open spaces as often as
possible


Limit use by children

2. Radiation from Smoking


Cigarette smoke contains radioactive lead
-
210 and
polonium
-
210



Each cigarette smoked can also be equated to one chest
x
-
ray


A non
-
smoker living with a smoker may receive the
equivalent of 12 chest x
-
rays per year as a result of second
-
hand smoke


Lead
-
210 and polonium
-
210 are deposited in the
bronchioles


Risk of cancers is increased with the presence of
other harmful substances in cigarette smoke


Carbon monoxide


Tar


Nicotine

3. Radiation In Medicine

Diagnostic radiology


Use of machines (e.g. X
-
ray) to obtain images
of the inside of the patient's body


X
-
rays can penetrate skin


Bone, fat, muscle, tumors and other masses all absorb
X
-
rays at different levels


The image on the film reveals distinct structures in the
body because of the different levels of exposure on
the film


Even with the risks, X
-
ray scanning is still a safer
option than surgery


Other diagnoses using radiation
include mammography and MRI scans

3
. Radiation In Medicine

Radiotherapy


Use of high energy x
-
rays and similar rays
to treat disease (usually cancer)


Radiation destroys the cancer cells in the
treated area


Although normal cells can also be
damaged by the radiotherapy, they can
usually repair themselves


Contributes to 40 per cent of all cured
cancers

4. Radiation from Appliances

Televisions


TVs emit X
-
rays


LCD (flat screen) TVs produce much less
radiation

Computers


Computers emit radio and microwaves


Wireless equipment (e.g. mouse, keyboard)
also emit some radiation


Sit at least:


1.9m away from TV


60 cm away from computer screens

4. Radiation from Appliances

Microwave Ovens


Microwaves affect the food


Structure of protein foods is changed
so
that a beneficial protein molecule in the
food becomes a harmful one


Placing plastic containers into the
microwave may cause
toxic plastic
molecules to leach into the food


Microwaves also leak out of the oven


keep a distance of
1.5
meters

4. Radiation from Appliances

Heating Appliances


Electric blankets generate EM
radiation, even after switched off


Electrically heated carpets and rugs,
under
-
carpet and under
-
floor heating
all produce substantial EM radiation


Electrical heaters also produce lot of
EM radiation

4. Radiation from Appliances

Personal Grooming Appliances


Hairdryers, electric shavers, electric
toothbrushes and similar personal
grooming products emit radiation at
their normal operating distance


People at higher risk should refrain
from using them

Significance


Even though common sources of
radiation only deal it in minute doses


The frequency of which we are
exposed to them are greater causes
for concern


The accumulation of these small doses
may greatly affect our health

People at Higher Risk


Children


Biologically more vulnerable


Thinner skulls


Tissues not fully developed


May not be able to control how much they use
cell phones, play on computers, watch TV etc,
and how close they sit to the screen.


Pregnant Women


Any cellular damage in a developing embryo
may have magnified consequences for the child


At risk of miscarriage if they are subjected to high
intensity EM radiation during pregnancy


Lower EM radiation levels may still damage the
foetus while not causing an actual miscarriage.


People At Higher Risk


People already suffering from chronic
degenerative conditions


The body is already using all its available energy
to heal itself


Does not have much energy to spare for
repairing the damage done by radiation


Workers in close proximity to electrical
machinery


Exposed to strong electromagnetic fields and
radiation

People At Higher Risk


Frequent users of appliances that emit
radiation


Spend more than a few minutes a day
talking on a cell phone pressed to their
ear etc


Table of Radiation
-
emitting Appliances


Especially vulnerable if they done every
day for years


In other words,
most of us are at risk

Radiation Protection


Increase distance from source


The intensity of radiation decreases with distance
from its source.


Reduce time exposed to source


If exposure cannot be avoided, try to spend as
little time near it as possible


If it doesn't need to be turned on, switch it
off


Radiation comes from many devices which are
left on unnecessarily, e.g. charger units for
batteries, cell
-
phones, laptops etc, computers
and printers

Radiation Protection


Shielding


Barriers of lead, concrete or water give good
protection from high levels of penetrating
radiation such as gamma rays


Intensely radioactive materials are often stored
or handled under water, or by remote control in
rooms constructed of thick concrete or lined with
lead


Containment


Highly radioactive materials are confined and
kept out of the workplace and environment


Nuclear reactors operate within closed systems
with multiple barriers which keep the radioactive
materials contained

References


http://www.world
-
nuclear.org/info/inf05.html



http://www.world
-
nuclear.org/education/ral.htm



http://science.howstuffworks.com/radiation.htm



http://www.wisegeek.com/what
-
is
-
electromagnetic
-
radiation.htm



http://www.howstuffworks.com/cell
-
phone
-
radiation.htm



http://www.hps.org/publicinformation/ate/q824.html



http://www.uraniumsa.org/about/radiation.htm



http://www.radiationanswers.org/radiation
-
introduction/types
-
of
-
radiation.html


References


http://orise.orau.gov/reacts/guide/define.htm



http://www.chem.duke.edu/~jds/cruise_chem/nuclear/expos
ure.html



http://www.docstoc.com/docs/23411087/Natural
-
and
-
Man
-
Made
-
Radiation
-
Sources



http://www.emwatch.com/index.html



http://www.uihealthcare.com/topics/medicaldepartments/c
ancercenter/prevention/preventionradiation.html


http://www.epa.gov/radiation/sources/tobacco.html



http://www.hpa.org.uk/Topics/Radiation/UnderstandingRadia
tion/UnderstandingRadiationTopics/MedicalRadiation/


http://health.howstuffworks.com/medicine/modern/nuclear
-
medicine.htm