PPT on Radioactive Decay

1. BIOLOGY
Radioactive and
Nuclear pollution
Presented by:
Vishva.j
Yuvan pramesh.s

2. Session objectives
➢Introduction
➢Sources
➢Effects in humans
➢Effects on environment
➢Types of radioactive pollution
➢Prevention
➢Waste management

3. INTRODUCTION
➢ Radioactive or nuclear pollution is defined
as the release of radiation from radioactive
substances into the air ,water or earth by
either human activities or naturally.
➢ The destruction caused by the radioactive
materials is because of the emission of
hazardous ionizing radiation . This is said to
be radioactive decay.
➢ There is a instability of the particles present
in the radioactive materials ,it can seriously
affect and even destroy plants , animals and
human life.

4. SOURCES OF RADIOACTIVE POLLUTION
Natural sources
➢ The earth itself is a
terrestrial radiation.
➢ Radioactive elements exists
naturally in soil and rock .
➢ Water contains small amounts
of dissolved Uranium ,
Thorium.
➢ All organic matter (both
animals and plants ) contains
radioactive carbon and
potassium.
Manmade source
➢ Nuclear explosions .
➢ Testing of nuclear weapons.
➢ Nuclear weapons production.
➢ Mining of radioactive ores
➢ Disposal of radioactive waste.
➢ Accidents at nuclear power
stations.

6. EFFECTS OF RADIOACTIVE POLLUTION
➢ Radioactive pollution is the kind of pollution which is caused due
to the radioactive decay of unstable heavy atoms nuclei. When
their radiations are emitted , their exposure can cause damage and
harm to the living cells as well as the environment.
➢ Radioactive substances are among the most toxic substances
known.
➢ Marie Curie , the Nobel laureate for discovery of radioactivity in
1903 , became the victim of radioactive pollution and died of
leukemia.
➢ The impact of radioactive pollution on human beings can vary
from mild to fatal ; the magnitude of the adverse effects depends
up on the level and duration of exposure to radioactivity.

7. EFFECTS ON THE ENVIRONMENT
➢ When soil is contaminated by radioactive substances, the harmful
substances are transferred into the plants growing on it.
➢ It leads to genetic mutation and affects the plant's normal
functioning. Some plants may die after such exposure, while
others may develop weak seeds.
➢ Eating any part of the contaminated plant, primarily fruits, poses
serious health risks. Since plants are the base of all food chains,
their contamination can lead to radioactive deposition all along
the food web.
➢ Similarly, when radioactive waste is washed up in a water source,
it can affect the entire aquatic food web.

8. TYPES OF RADIOACTIVE POLLUTION
➢ Continuous pollution : This type of condition exists in uranium
mines , nuclear reactors , test labs etc. where the woman under
continuous exposure to radioactive contaminants and protective
clothing is required to avoid exposure .
➢ Accidental pollution : This type of condition exist during
accidental exposure to radiations by virtue of equipment failure ,
radiation leak , faulty protection equipment etc.
➢ Occasional pollution : This condition exists during isolated
experiment or test of nuclear substance.

9. PREVENTION OF RADIOACTIVE DECAY
➢ Nuclear devices should be exploded under ground .
➢ Contaminants may be employed to decrease the radioactive
emissions .
➢ Production of radioisotopes should be minimised .
➢ Extreme care should be exercised in the disposal of industrial
waste contained with radionuclide .
➢ Use of high chimney and ventilations at the working place where
radioactive contamination is high .
➢ In nuclear reactors , closed cycle system with gaseous coolants of
very high purity may be used to prevent extraneous activation
products.
➢ Fission reaction should be minimised .
➢ In nuclear mines , wet drilling may be employed along with under
ground drainage.

10. WASTE MANAGEMENT
• Henceforth it is important to manage the waste properly
• The threat of radioactive waste can be minimized to a
great degree, or even completely negated, if it is stored
for an appropriate time before being dumped.
• As explained earlier, any radioactive substance
naturally undergoes radioactive decay until a
nonradioactive isotope of the element, or a different,
nonradioactive element is formed. The time required to
achieve a nonradioactive byproduct varies with every
radioactive element. Till then, these materials have to
be kept in an isolated condition, so that the
environment is not exposed to it.

11. WASTE MANAGEMENT
• Various processes have been put forth to reduce the
radioactivity of the stored byproducts. Some of the
most promising methods are vitrification(forming a
mixture of the radioactive waste and glass and storing it
in steel containers), reusing the radioactive waste until
it becomes sufficiently benign (although it is not
feasible right now, research is being done in the field),
and storing spent nuclear fuel in dry casks after it has
been treated in spent fuel pools for a long period, at
least a year.

12. THE END
Thank you for spending your prec
Time with us!