This document discusses various types of marine pollution including sewage, pesticides, plastic wastes, metallic wastes, oil, heat, radioactive waste, and dredge spoils. It outlines the sources and effects of each pollutant, such as how sewage can cause deoxygenation and infections, how pesticides accumulate up the food chain and affect wildlife reproduction, and how oil spills can smother and poison marine life. The document also covers methods to prevent and control marine pollution like stabilizing ecosystems, removing pollutants, skimming oil spills, and removing heat from power plant wastewater before disposal.

1. MARINE
POLLUTION

2. CONTENTS
• INTRODUCTION
• MARINEPOLLUTION
• POLLUTANTS:SOURCESANDTHEIR
EFFECTS
• PREVENTIONANDCONTROLOFMARINE
POLLUTION
• CONCLUSION
• REFERENCES

3. MARINEPOLLUTION
• It is defined as the
discharge
substances
of waste
into the sea
resulting in harm to living
resources, hazards to
human health, hindrance to
fishery and impairment of
quality for useof sea-water.
Marine pollution is
associated with the changes
in physical, chemical and
biological conditions of the
seawater.
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4. POLLUTANTS:SOURCESANDTHEIR
EFFECTS
Pollutants can simply define as the materials which cause
pollution. The following are the important pollutants that
causethe marine pollution.
Sewage
Pesticides
Plastic wastes
Metallic wastes
Oil
Heat
Radioactive waste
Dredge spoil
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5. SEWAGE
Sewagemay be entering the
sea
– Bydirect drainage
– From inland towns and
industries.
– Tipping at seafrom ships.
Detrimental effects of
sewageinclude
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Deoxygenation
Foul deposits, Reduced salinity,
Infection and toxic residues,

6. PESTICIDES
• Pesticides are organically active
chemicals which are used for killing
the pests.
Pesticides may enter the oceans
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– From the atmosphere after aerialspraying,
– From overland runoff of sprayedareas.
– From intentional dumping in thesea.
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Pesticides affects food chaindirectly.
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
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cause patches
immunotoxicity,
on the skin,
kidney damage,
weight lossand tumor formation in
otters.

7. PLASTICWASTES
• 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, asit often
looks similar to their naturalprey.
Plastic debris, when bulky or tangled, is
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difficult to pass, and may become
permanently lodged in the digestive
tracts of these animals, blocking the
passageof food and causingdeath
through starvation or infection.
Fishingnets entangle fish, dolphins, sea
turtles, sharks, dugongs, crocodiles, sea
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restricting movement,
birds, crabs, and other creatures,
causing
starvation, laceration and infection, and,
in those that need to return to the
surface to breathe, suffocation.

8. METALLICWASTES
• Metallic chemical elements have a relatively
high density and toxic or poisonous at low
concentrations. Examples are mercury, lead,
nickel, arsenic, cadmium and soon.
Metallic wastes can be enter the marine
environment naturally
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– through weathering of theearth’s crust.
– from rivers or by directdischarges.
– through the atmospherealso.
– Thesecan enter the seathrough 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 aquaticlife.
When we consume suchfishes, it will affect
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our nervous system, kidneys, brains,
respiratory system or even it will lead us to
death.

9. OIL
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Oil may enter the sea water by number of
ways asfollows;
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 inport
• Tanker accidents and maritime accidents due
to collision, fire, explosion or grounding also
result in oil releaseinwater.
Oil leakage from pipelines
The blowout of wells, disposal of drilling mud,
accidental damages to offshore drilling rigs add
to oil pollutionin 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 insea.

10. Oil pollution in Gulf ofMexico

11. OIL
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Theoverall detrimental effects of oil pollution sea
water are asfollows;
• Reduction in dissolvedoxygen.
• Reduction in lightpenetration.
• Oil spilling causeslethal toxicity toaquatic flora.
• Smothering coats of oil have killed lichens and
algae along the shorelines.
S
ea otters will die when their fur become
saturated with oil by losinginsulation.
• Waste from oil refineries and discharged
petroleum from ships cause heavy damage to
fishery.
Hydrocarbons in oil get incorporated in body
tissues of marineanimals.
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 and100ppm.
When men consume the fishes from oil polluted
sea water, it may result in breathing problems, and
candamageliver and kidneys.
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14. SEDIMENTPLUMES
(BYDEEPSEAMINING)
• 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 typesof
plumes:
Near bottom
plumes Surface
plumes
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15. HEAT
• Accumulation of unusable heat from
human activities can disrupts
ecosystemsin the marineenvironment.
The most important sources of thermal
marine pollution are the nuclear power
plants and Thermal power plants.
Thesepower plants use the sea water
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for cooling. This water is generally
returned to the sea at temperatures 11
to 220C (20-400F), 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 marinelife.
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16. RADIOACTIVEWASTE
Radioactive materials enter to the
oceansmainly from followingways:-
From natural backgroundsource:
From fallout of nuclear weaponstesting.
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• From operation of nuclear reactors
through intentional and unintentional
direct releases.
• Mining and processingof ores to produce
radioisotopes.
Emission from the industrial use of
nuclear energy.
Leakage from underground nuclear
detonations.
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• From shipboard reactors.
Radioactive contaminate seawater will
consumed by plants during
photosynthesis acts as a medium for
radioactivity in them. By this, radionuclide
enter into the food chain of marinewater.
• When men consume these radionuclide
fishes, it will cause cancers, leukemia, eye
cataract, DNA breakage and carcinoma in
humans.

17. DREDGESPOILS
• 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,
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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.

18. PREVENTIONANDCONTROLOF
MARINEPOLLUTION
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Stabilization of the ecosystem
Reutilization, recycling, renovation and
recharge of the waste
Removal of the pollutants
Tocontrol the oil pollution, following
methods are used
– Skimming
– By spreading a high density
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powder over the oil patch, it can
be sunk to thebottom.
Biodegradation
Burning
Using a suitable absorbing
material.
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• Heat can be removed from condenser
cooling waters prior to their disposal
into the marinewater.