Radioactive contamination can occur when radioactive materials are released unintentionally into the environment through events like nuclear accidents, explosions, or industrial incidents. Contamination can affect people, animals, and the surrounding area through external exposure from contact with contaminated surfaces or internal exposure from inhaling or ingesting radioactive substances. The health effects of contamination depend on the radioactive material, amount of exposure, and whether it is external or internal contamination. Proper containment and safety precautions can help prevent radioactive contamination.

1. Radio-Active Contamination and Radiation Exposure
-Radioactive contamination, also called radiological
contamination, is the deposition of, or presence
of radioactive substances on surfaces or within solids,
liquids or gases (including the human body), where their
presence is unintended or undesirable
Radioactive contamination is unregulated
disbursement of radioactive materials, such as radioactive
gases, liquids, or particles, in a place where they may harm
individuals or equipment. Plants, buildings, people, and
animals can all become contaminated by radioactive
materials that are disbursed into the environment. Air,
water, waste, and surfaces are other possible sources of
radioactive contamination. For example, if a radioactive
substance is inadvertently spilled on a floor, individuals
may spread the substance simply by walking on the
contaminated floor.
A number of events can cause
radioactive contamination. If a nuclear explosion occurs,
for example, it can result in the distribution of
radioactive contamination. This phenomenon is usually
known as nuclear fallout. When a radioactive substance is
not properly sealed in a base container, it can spread to
other objects, causing radioactive contamination.
Radioactivitycontamination can also be the unavoidable
result of certain practices. For instance, radioactive
materials are automatically released during nuclear fuel
reprocessing.
Radioactive waste contamination can occur
externally, internally, or through the environment.
External contamination occurs when the radioactive
material, usually in the form of dust, powder, or liquid,
gets on an individual’s hair, skin, or clothing.
Internal contamination takes places when an individual
inhales, swallows, or absorbs a radioactive substance.
When radioactive material is distributed or released into
the environment, environmentalcontamination occurs.

2. Causes
.
How Exposure or Contamination Can Happen
Radioactive materials could be released into the environment in the following ways:
• A nuclear power plant accident
• An atomic bomb explosion
• An accidental release from a medical or industrial device
• Nuclear weapons testing
• An intentional release of radioactive material as an act of terrorism
Fukushima Disaster – March 11, 2011
A massive 8.9-magnitude quake hit
northeast Japan on Friday, causing dozens of
deaths, more than 80 fires, and a 10-meter (33ft) tsunami along parts of the country’s
coastline. Homes were swept away and damage
was extensive. And the disaster didn’t end with
this. Eleven reactors at four sites near Japan’s
northeast coast were shut down per seismic
emergency procedures. Five reactors at two
sites in the Fukushima prefecture declared
emergencies due to loss of normal site power
and backup emergency power. According to a
British nuclear expert the explosion at the Fukushima I nuclear plant looks likely to be a “significant
nuclear event” with a bigger impact on public health than the 1979 meltdown at Three Mile Island. As of
15 March, the Finnish nuclear safety authority estimated the accidents at Fukushima to be at Level 6 on
the INES. On 24 March, a scientific consultant for Greenpeace, working with data from the Austrian
ZAMG and French IRSN, prepared an analysis in which he rated the total Fukushima I accident at INES
level 7. The accident caused nuclear contamination in the surrounding environment, water, milk,
vegetable and other food items. People living in surroundings were moved to safe shelters and food
grown in the area was banned for sale. The Japanese government in handling the situation in the most
efficient and amazing way that anyone can imagine. Screening is being done and people are given
proper medical care. Initially 3 workers were affected by the radiation.

3. Soviet Submarine K-19 Nuclear Accident
This accident was expanded on
by a commander’s overzealous pride,
when Nikolai VladimirovichZateyev
refused American aid during a
malfunction in his submarine’s nuclear
reactor’s coolant system. When his crew
protested being forced into a radioactive
prison, the commander threw all their
weapons overboard and the K-19 was
dragged home by a diesel powered sub,
contaminating the water, crew, and
commander as it went.
Sources
Power Plant, Nuclear Reasearch Facilities, and Military activities.
Effects
It contaminates everything around especially food, making it not edible, too much
exposure to the radiation may also lead to genetic mutation that may result to their next
generation to have an abnormalities or carrying a genes with an unidentified diseases, it also
causes cancer and other diseases that may lead to sudden death.
Biological effects
The biological effects of internally deposited radionuclides depend greatly on the activity,
the biodistribution, and the removal rates of the radionuclide, which in turn depends on its
chemical form, the particle size, and route of entry. Effects may also depend on the
chemical toxicity of the deposited material, independent of its radioactivity. Some radionuclides
may be generally distributed throughout the body and rapidly removed, as is the case
withtritiated water.
Some organs concentrate certain elements and hence radionuclide variants of those
elements. This action may lead to much lower removal rates. For instance, the thyroid gland
takes up a large percentage of any iodine that enters the body. Large quantities of inhaled or
ingested radioactive iodine may impair or destroy the thyroid, while other tissues are affected to
a lesser extent. Radioactive iodine-131 is a common fission product; it was a major component
of the radiation released from the Chernobyl disaster, leading to nine fatal cases of
pediatric thyroid cancer and hypothyroidism. On the other hand, radioactive iodine is used in the
diagnosis and treatment of many diseases of the thyroid precisely because of the thyroid's
selective uptake of iodine.

4. Mental health effects
The consequences of low-level radiation are often more psychological than radiological.
Because damage from very-low-level radiation cannot be detected, people exposed to it are left
in anguished uncertainty about what will happen to them. Many believe they have been
fundamentally contaminated for life and may refuse to have children for fear of birth defects.
They may be shunned by others in their community who fear a sort of mysterious contagion.
Forced evacuation from a radiation or nuclear accident may lead to social isolation,
anxiety, depression, psychosomatic medical problems, reckless behavior, even suicide. Such
was the outcome of the 1986 Chernobyl nuclear disaster in the Ukraine. A comprehensive 2005
study concluded that "the mental health impact of Chernobyl is the largest public health problem
unleashed by the accident to date". Frank N. von Hippel, a U.S. scientist, commented on the
2011 Fukushima nuclear disaster, saying that "fear of ionizing radiation could have long-term
psychological effects on a large portion of the population in the contaminated areas".
Such great psychological danger does not accompany other materials that put people at
risk of cancer and other deadly illness. Visceral fear is not widely aroused by, for example, the
daily emissions from coal burning, although, as a National Academy of Sciences study found,
this causes 10,000 premature deaths a year in the US. It is "only nuclear radiation that bears a
huge psychological burden — for it carries a unique historical legacy".
Prevention
Avoid using nuclear war heads as a source of world power.
Control
There is no possible control for the contamination if ever there is a leak but to abandon
the place with about kilometers of radius from the source.

5. Red Tide Phenomenon
- Red tide is a common name for a
phenomenon known as an algal bloom
where causes discoloration in the water
near the shoreline. Often it turns a reddishbrown colour, hence the name red tide.
There have been occurrences where the
water has turned a yellow, brown, or even a
purple shade.
Causes
Red Tide is caused by a rapid population growth of microscopic plankton. This
microscopic plankton release toxins that have severe effects on marine life and humans. The
toxins are environmental chemicals that can interfere with metabolism, nerve conduction, and
the central nervous system.
Sources
Microscopic planktons that releases toxin.

6. Effects
Organisms involved in Red Tide are not
always harmful to the marine life, but
unfortunately there is a great number that are.
These harmful algal blooms (HABs) have
caused death among fish, birds, manatees, and
several other vertebrate species. Eating the
toxic plankton, eating other organisms already
infected with the toxins, or simply by exposure
through the water can contaminate organisms.
The toxins do not affect filter-feeding shellfish
even though the toxins are concentrated in their
organs. Other fish, however, are not so lucky
and end up being victims to the powerful red
tide.
Prevention- none(because its naturally occurring in the environment)
Control
Satellite Imaging
Technological advancements such as satellite imagery have allowed scientists to better
track and monitor harmful algal blooms. Tracking and monitoring red tide algae helps reduce
harmful effects of the algae by providing warnings against eating infected shellfish and against
swimming in infected waters

7. Acid Rain
Acid rain is rain consisting of water droplets that are unusually acidic because of
atmospheric pollution - most notably the excessive amounts of sulfur and nitrogen released
by cars and industrial processes. Acid rain is also called acid deposition because this term
includes other forms of acidic precipitation such as snow.
Acidic deposition occurs in two ways: wet and dry. Wet deposition is any form of
precipitation that removes acids from the atmosphere and deposits them on the Earth’s
surface. Dry deposition polluting particles and gases stick to the ground via dust and smoke
in the absence of precipitation. This form of deposition is dangerous however because
precipitation can eventually wash pollutants into streams, lakes, and rivers.
Acidity itself is determined based on the pH level of the water droplets. PH is the
scale measuring the amount of acid in the water and liquid. The pH scaleranges from 0 to 14
with lower pH being more acidic while a high pH is alkaline; seven is neutral. Normal rain
water is slightly acidic and has a pH range of 5.3-6.0. Acid deposition is anything below that
scale. It is also important to note that the pH scale is logarithmic and each whole number on
the scale represents a 10-fold change.

8. Causes
There are two main causes of acid rain; the natural process in which caused by the
natural environment and anthropogenic that is from to too much emission of gas in the
atmosphere due to Industrialization.
Urbanization
Industrialization
Volcanic Eruption

9. Sources
Emissions from vehicle’s, factories and other Industrial facilities and also other
compounds from the wastes made by human in which is evaporated into the atmosphere.
Effects
Acid rain has been shown to have
adverse impacts on forests, freshwaters and
soils, killing insect and aquatic life-forms as
well as causing damage to buildings, forests
and having impacts on human health.
Prevention
Avoid too much emission of gasses
that can aid to acid rain, and use public
transport instead of using private vehicle’s if it
possible, to reduce the amount and control
the possible effects
Control
Many coal-firing power stations use flue-gas desulfurization (FGD) to remove sulfurcontaining gases from their stack gases. For a typical coal-fired power station, FGD will remove
95% or more of the SO2 in the flue gases. An example of FGD is the wet scrubber which is
commonly used. A wet scrubber is basically a reaction tower equipped with a fan that extracts
hot smoke stack gases from a power plant into the tower. Lime or limestone in slurry form is
also injected into the tower to mix with the stack gases and combine with the sulfur dioxide
present. The calcium carbonate of the limestone produces pH-neutral calcium sulfate that is
physically removed from the scrubber. That is, the scrubber turns sulfur pollution into industrial
sulfates.

10. Eutrophication
Eutrophication is the accumulation of
nutrients in aquatic ecosystems. It alters the
dynamics of a number of plant, animal and
bacterial populations; thus, bringing about
changes in community structure. It is a form of
water pollution and like all other forms of
pollution is the result of human activities
influencing ecological cycles. An increase in
chemical nutrients — compounds containing
nitrogen or phosphorus in an ecosystem, and
may occur on land or in water.
Causes
Eutrophic and hypoxic events has been attributed
to the rapid increase of nutrients resulting to increase of
number of plant, animal and bacterial populations
because of intensive agricultural practices, industrial
activities, and population growth which together have
increased nitrogen and phosphorus flows in the
environment especially in the bodies of water.

11. Sources
It came from the excess nutrients like agricultural fertilizers, domestic sewage and
livestock wastes.
Effects
Many ecological effects can arise from stimulating primary production
commonlydecreased biodiversity, changes in species composition and dominance, and toxicity
effects.
Prevention
Avoid too much use of agricultural fertilizers to avoid run off from the farm and avoid
dumping waste in the bodies of water.
Control
Nitrogen testing and modeling
Soil Nitrogen Testing (N-Testing) is a technique that helps farmers optimize the amount of
fertilizer applied to crops. By testing fields with this method, farmers saw a decrease in fertilizer
application costs, a decrease in nitrogen lost to surrounding sources, or both.By testing the soil
and modeling the bare minimum amount of fertilizer needed, farmers reap economic benefits
while reducing pollution.

12. Green House Effect
Atmospheric scientists first used the term 'greenhouse effect' in the early 1800s. At that
time, it was used to describe the naturally occurring functions of trace gases in the atmosphere and
did not have any negative connotations. It was not until the mid-1950s that the term greenhouse
effect was coupled with concern over climate change. And in recent decades, we often hear about
the greenhouse effect in somewhat negative terms. The negative concerns are related to the
possible impacts of an enhanced greenhouse effect. This is covered in more detail in the Global
Climate Change section of this Web site. It is important to remember that without the greenhouse
effect, life on earth as we know it would not be possible.
While the earth's temperature is dependent upon the greenhouse-like action of the
atmosphere, the amount of heating and cooling are strongly influenced by several factors just as
greenhouses are affected by various factors.
In the atmospheric greenhouse effect, the type of surface that sunlight first encounters is the
most important factor. Forests, grasslands, ocean surfaces, ice caps, deserts, and cities all absorb,
reflect, and radiate radiation differently. Sunlight falling on a white glacier surface strongly reflects
back into space, resulting in minimal heating of the surface and lower atmosphere. Sunlight falling on
a dark desert soil is strongly absorbed, on the other hand, and contributes to significant heating of
the surface and lower atmosphere. Cloud cover also affects greenhouse warming by both reducing
the amount of solar radiation reaching the earth's surface and by reducing the amount of radiation
energy emitted into space.
Scientists use the term albedo to define the percentage of solar energy reflected back by a
surface. Understanding local, regional, and global albedo effects is critical to predicting global climate
change.

13. Causes
Major cause of the greenhouse effect is the too much presence of gases in the
atmosphere that causes radiation from the sun unable tobounce back into the outer space.
Sources
Just like the acid rain, this was also from emissions of the vehicle’s, factories and other
Industrial facilities that produces too much compounds in the earth’s atmosphere.

14. Effects
Increase in Greenhouse Gases
The increase in the concentration of carbon dioxide, one of the three
majoratmosphericcontributers to the greenhouse effect has been carefully documented at the
Mauna Loa Observatory in Hawaii. The 1990 rate of increase was about 0.4% per year. The
interesting cyclic variations represent the reduction in carbon dioxide by photosynthesis during
the growing season in the northern hemisphere.
Current analysis suggests that the combustion of fossil fuels is a major contributer to the
increase in the carbon dioxide concentration, such contributions being 2 to 5 times the effect of
deforestation
Because of the greenhouse effect, a significant increase in greenhouse gases should
translate to increase in global mean temperature causing polar caps to melt and sea level to rise
that may result to shrinking of the continental land areas. Currently, there is a view among many
scientists and layman that there is indeed an increase in globally averaged temperatures since
the mid-20th century and that it is most likely a result of an observed increase in anthropogenic
greenhouse gas concentrations

15. Prevention
Avoid using aerosols, sprays and other chemicals that may help to the rise of the
temperature.
Control
To control this effect, the cause of excess Co2 due to accumulation of CO2 producing
industries should be scattered in such a way that percentage of CO2 to be maitained at 0.6% or
below by planting tree plantations which would result in consuming CO2 for food production by
green leaves of trees and plants. In order to have controlled life in reducing foul gases that
cause greenhouse effect and pollution.