This document discusses marine pollution and its causes and effects. It begins with an introduction noting that while oceans are vital, human activity has degraded marine habitats. It then defines marine pollution and discusses various pollutants like sewage, pesticides, plastics, metals, oil, thermal pollution and their harmful effects. These pollutants accumulate in marine life and enter the human food chain. The document concludes by emphasizing the importance of preventing and controlling marine pollution to protect ocean ecosystems and human health.

1. SEMINAR ONSEMINAR ON
MARINE POLLUTIONMARINE POLLUTION

2. CONTENTS
• INTRODUCTION
• MARINE POLLUTION
• POLLUTANTS: SOURCES AND THEIR
EFFECTS
• PREVENTION AND CONTROL OF MARINE
POLLUTION
• CONCLUSION
• REFERENCES

3. INTRODUCTION
• Oceans cover about 71% of the
Earth’s surface.
• They play an important role in the
chemical and biological balance of
the life on the earth.
• They are vital to our food security,
commerce and transportation.
• But human activity has troubled
the health of oceans.
• The habitats of marine mammals
and fish have been degraded
severely, with pollution responsible
for the mass deaths of fish,
mammals and corals.
• Organochloric pollutants,
pesticides, polychlorinated
biphenyls (PCBs) and a range of
other toxic pollutants accumulate
within fishes later moving up the
food chain to cause reproductive
disorders.

4. MARINE POLLUTION
• It is defined as the
discharge of waste
substances into the sea
resulting in harm to living
resources, hazards to
human health, hindrance to
fishery and impairment of
quality for use of sea-water.
• Marine pollution is
associated with the changes
in physical, chemical and
biological conditions of the
sea water.

5. POLLUTANTS: SOURCES AND THEIR
EFFECTS
Pollutants can simply define as the materials which cause
pollution. The following are the important pollutants that
cause the marine pollution.
• Sewage
• Pesticides
• Plastic wastes
• Metallic wastes
• Oil
• Sediment plumes (by deep sea mining)
• Heat
• Radioactive waste
• Dredge spoil

6. SEWAGE
 Sewage may be entering the
sea
– By direct drainage
– From inland towns and
industries.
– Tipping at sea from ships.
 Detrimental effects of
sewage include
– Eutrophication
– Deoxygenation
– Foul deposits, Reduced salinity,
Infection and toxic residues,

7. PESTICIDES
• Pesticides are organically active
chemicals which are used for killing
the pests.
• Pesticides may enter the oceans
– From the atmosphere after aerial spraying,
– From overland runoff of sprayed areas.
– From intentional dumping in the sea.
• Pesticides affects food chain directly.
• These are more and more
concentrated in fish, seagulls, seals,
penguins and marine planktons.
• PCBs have been found to have a
series effect on this aquatic animal’s
reproductive cycle. And known to
cause patches on the skin,
immunotoxicity, kidney damage,
weight loss and tumor formation in
otters.

8. PLASTIC WASTES
• The mass of plastic in the oceans may be
as high as one hundred million metric
tons.
• Many animals that live on or in the sea
consume flotsam by mistake, as it often
looks similar to their natural prey.
• Plastic debris, when bulky or tangled, is
difficult to pass, and may become
permanently lodged in the digestive
tracts of these animals, blocking the
passage of food and causing death
through starvation or infection.
• Fishing nets entangle fish, dolphins, sea
turtles, sharks, dugongs, crocodiles, sea
birds, crabs, and other creatures,
restricting movement, causing
starvation, laceration and infection, and,
in those that need to return to the
surface to breathe, suffocation.

9. METALLIC WASTES
• Metallic chemical elements have a relatively
high density and toxic or poisonous at low
concentrations. Examples are mercury, lead,
nickel, arsenic, cadmium and so on.
• Metallic wastes can be enter the marine
environment naturally
– through weathering of the earth’s crust.
– from rivers or by direct discharges.
– through the atmosphere also.
– These can enter the sea through oil spill
also.
• The use of antifouling paint on the bottoms of
boats has been implicated as a major source of
heavy metals in waters.
• These toxic metals can accumulate in the
tissues of many species of aquatic life.
• When we consume such fishes, it will affect
our nervous system, kidneys, brains,
respiratory system or even it will lead us to
death.

10. OIL
 Oil may enter the sea water by number of
ways as follows;
• Cargo tanker washings at sea and international
discharge of oily wastes from tank washings
and accidental spillages pollute the sea water
severely.
• Bilge pumping at sea
• Import oil losses: collisions in port
• Tanker accidents and maritime accidents due
to collision, fire, explosion or grounding also
result in oil release in water.
• Oil leakage from pipelines
• The blowout of wells, disposal of drilling mud,
accidental damages to offshore drilling rigs add
to oil pollution in water.
• Oily wastes from oil fields or refineries near
the coast.
• Oil spills mixed with urban sewage, silt,
plastics, pesticides and insidious toxic
compounds are pervasive and complex the
pollution problems in sea.

11. Oil pollution in Gulf of Mexico

12. An Oil Slick from a Satellite

13. OIL
 The overall detrimental effects of oil pollution sea
water are as follows;
• Reduction in dissolved oxygen.
• Reduction in light penetration.
• Oil spilling causes lethal toxicity to aquatic flora.
• Smothering coats of oil have killed lichens and
algae along the shore lines.
• Sea otters will die when their fur become
saturated with oil by losing insulation.
• Waste from oil refineries and discharged
petroleum from ships cause heavy damage to
fishery.
• Hydrocarbons in oil get incorporated in body
tissues of marine animals.
• When the concentration of crude oil in the sea
water reaches 0.02ppm, fish eggs begin to hatch
irregularly or late, while the development of
already-hatched young fish or larval crabs and
lobsters becomes abnormal at oil concentrations
between 1 and 100ppm.
• When men consume the fishes from oil polluted
sea water, it may result in breathing problems, and
can damage liver and kidneys.

16. SEDIMENT PLUMES
(BY DEEP SEA MINING)
• Because of deep sea mining,
the removing parts of the sea
floor, disturbs the habitat of
benthic organisms.
• Plumes are caused when the
tailings from mining (usually
fine particles) are dumped back
into the ocean, creating a cloud
of particles floating in the
water.
 There are two types of
plumes:
• Near bottom plumes
• Surface plumes

17. HEAT
• Accumulation of unusable heat from
human activities can disrupts
ecosystems in the marine environment.
• The most important sources of thermal
marine pollution are the nuclear power
plants and Thermal power plants.
• These power plants use the sea water
for cooling. This water is generally
returned to the sea at temperatures 11
to 220
C (20-400
F), which is higher than it
was initially.
• One nuclear power plant may use as
much as one billion gallons of sea water
per day.
• Marine life is extremely sensitive to
changes in water temperature. Higher
temperatures can lead to premature
spawning, fish migration, lack of oxygen
or death of marine life.

18. RADIOACTIVE WASTE
 Radioactive materials enter to the
oceans mainly from following ways:-
• From natural background source:
• From fallout of nuclear weapons testing.
• From operation of nuclear reactors
through intentional and unintentional
direct releases.
• Mining and processing of ores to produce
radioisotopes.
• Emission from the industrial use of
nuclear energy.
• Leakage from underground nuclear
detonations.
• From shipboard reactors.
 Radioactive contaminate sea water will
consumed by plants during
photosynthesis acts as a medium for
radioactivity in them. By this, radionuclide
enter into the food chain of marine water.
• When men consume these radionuclide
fishes, it will cause cancers, leukemia, eye
cataract, DNA breakage and carcinoma in
humans.

19. DREDGE SPOILS
• Dredge spoils constitute the greatest
pollutant input by volume to the
oceans. Spoils from dredging or
mining of offshore minerals are
deposited within a few miles of
shore, where the potential impact is
the greatest.
• Often they also contain sewage or
industrial waste solids and solids
from street runoff. Consequently,
they often contain objectionable
amounts of hazardous chemicals,
pathogens, or oil and may exert a
high oxygen demand on the
surrounding environment.
 The damage which can be caused by
dredging is two fold:
1. That occurring at the dredging
site, and
2. That occurring at the dredge
spoils disposal area.

20. PREVENTION AND CONTROL OF
MARINE POLLUTION
• Stabilization of the ecosystem
• Reutilization, recycling, renovation and
recharge of the waste
• Removal of the pollutants
• To control the oil pollution, following
methods are used
– Skimming
– By spreading a high density
powder over the oil patch, it can
be sunk to the bottom.
– Biodegradation
– Burning
– Using a suitable absorbing
material.
• Heat can be removed from condenser
cooling waters prior to their disposal
into the marine water.

21. PREVENTION AND CONTROL OF
MARINE POLLUTION
• Removal of phosphorus by electrolysis.
• Adopting appropriate methods to remove
heavy metals from the marine water.
• Radioactive wastes can be removed or
reduced by the ion-exchange techniques,
precipitation of radio-nuclides.
• The impacts of deep sea mining can be
minimize or reduced by using proper mining
techniques.
• Creating awareness on marine pollution.
• Local communities near sea must protect
sea.
• Management by government
• Incentives must be offered for conservation.
• Industrial units should be equipped with
pollution control instruments.

22. CONCLUSION
• Oceans cover the earth’s surface about 71% and play
an important role in the chemical and biological
balance of the life on the earth.
• These are rich with marine resources like minerals, oil
and marine life and the sea food supplies meet a
substantial food requirement of the world’s population.
• If the marine life affected by the pollution and if they
carry pollutants in its biomass, the human population
may get the impact while consuming such resources.
Hence it is necessary to aware about the marine
pollution, and to protect the marine water from the
pollutants. So, necessary to prevent and control this
pollution.
• Let us save our oceans and the huge marine ecosystem.

23. REFERENCES
BOOKS
• Asha Rao S. N.(2004), Environmental studies, Chethana book house, pp:128-130
• A K Tripathi, A K Srivastava and S N Pandey (edited , 1993), Advances in environmental sciences, Ashish
publishing house, pp:93-109
• B K Sharma(6th
edition, 2001), Environmental chemistry , Goel publishing house, Meerut, pp:64-74
• D K Kumarswamy, Mr. A. Alayappa modes, Dr. M Vasanthy(1st
edition, oct,2004), Environmental studies,
Bharathidaran University, Tiruchirapalli, pp:142-145
• K. Siddhartha(1999), Oceanography, a brief introduction, Kisalaya publishing pvt ltd, pp:310-314
• Paul. L. Bishop(1983), Marine pollution and its control , McGraw-Hill Book Company.
• P K Goel (2000), Water pollution: causes, effects and control, new age international (p) ltd.
WEBSITES
• www. wikipedia. org.
• www. geology.com
• www. ask.com
• www.oeceanimages.com
• www.earthobserver.org
• Google images
• www.mcsuk.org/marineworld/pollution.html
• www.worldstats.org/general_world/principal_environmental_treaties.html
• www.cmc-ocean.org
• www.oceanlink.island.net/ask/pollution.html

24. THANK YOUTHANK YOU