Marine Pollution

1. Dr. P. SURESHKUMAR,
M. Sc., M. Phil., Ph.D., M.B.A.,
Assistant Professor in Environmental Sciences
Faculty of Marine Sciences
Annamalai University
Parangipettai-608 502
Mob. 8903041579
sure2004@gmail.com
By
MARINE POLLUTION

2. Marine pollution
"Introduction of man, directly or indirectly, of substances or
energy into the marine environment (including estuaries)
resulting in such deleterious effects as harm to living resources,
hazard to human health, hindrance to marine activities including
fishing, impairment of quality for use of sea-water, and reduction
of amenities.” – GESAMP
Definition

3.  Impacts on living resources
 Hazards to human health
 Hindrance to marine activities
 Impairment of quality of seawater
 Reduction of amenities
 Loss of aesthetic beauty
 Impacts on the sensitive habitats
General impacts
Marine pollution
Contd..

4. Sources of pollution
Land-based sources
 Agricultural run-off
 Municipal and industrial wastes
Sea-based sources
 Oceanic dumping
 Offshore oil spills

5. Point and Non-Point Sources
Point source – refers to a single identifiable source of pollutants eg.
effluent outfall
Non-point source – refers to diffuse source of pollutants eg. Acid rain,
dust storms
NONPOINT SOURCES
POINT
SOURCES
Urban streets
Suburban
development
Wastewater
treatment
plant
Rural homes
Cropland
Factory
Animal feedlot
Contd..

6. Discrete vs. Chronic Pollution
 Discrete (short term) – eg. an oil spill, the effects of which
diminish with time
 Chronic (long term) – eg. nutrient input, effluent discharge
Types of pollution

7. Types of pollution
Pollution
Oil
(Petroleum
hydrocarbons)
Eutrophication
Conservative
Metals
Halogenated
hydrocarbons
Thermal
Radioactive
Litter &
Plastic debris
Contd..

8. Oil pollution
Oil pollution is mostly used to
describe marine oil spills, where oil
is released into the ocean or coastal
waters.
Oil spills are due to the following:
 crude oil from tankers
 offshore platforms
 drilling rigs and wells
 spills of refined petroleum
products (such as gasoline, diesel)
 spill of any oily refuse or waste
oil

9. Oil pollution
Sources
Contd..
Source: UNEP

10. Exxon Valdez Oil Spill
– March 29, 1989
• Almost 44
million liters
(11.6 million
gallons) of oil
spilled into
Prince William
Sound, AK

11. World’s Largest Oil Spills

12.  When oil is spilled on sea it spreads
over the surface to form a thin film
– called oil slick
 Light oil spreads faster than heavy
wax oil
 Low molecular weight fractions
evaporate
 Water soluble components dissolve
 Non-water soluble components
emulsify and forms a viscous mass
– “chocolate mousse”
 Heavy residues form tar balls
Oil pollution
Fate
Contd..

13. Chocolate mousse
Tar balls
Oil pollution
Fate
Contd..

14.  Effects – Impairment of marine life
 Plankton, esp. neuston at highest
risk – exposed to water soluble
components leaching from oil
 Fixed vegetation –Sea grass beds–
killed or flowering inhibited
 In Mangroves – lenticels clogged
with oil oxygen level in sediments
drops – death
 Sea birds –buoyancy and thermal
insulation lost
Oil pollution
Impacts
Contd..

15. Oil Spills
 1. Oil spills have huge and immediate economic, social, and environmental impacts.
2. Local people lose their livelihoods as fisheries and tourism areas are temporarily
closed; the clean up costs are enormous; and tens of thousands of marine animals
and plants are killed or harmed.
3. And the damage goes on. The chemicals used to break up the oil can be toxic, and
it's impossible to remove all the spilled oil. Even after an area has been cleaned up,
it can take a decade or more to fully recover.
4. There's also the problem of the oil that goes down with the ship, which can
contaminate the seabed and marine organisms.
5. This oil can also resurface. In 2001, a cyclone off the island of Yap in Micronesia
disturbed the oil tanker USS Mississinewa, which was sunk during World War II. For
two months, thousands of liters of oil and gasoline leaked out of the rusted ship
wreck onto the beaches of the atoll, stopping the 700 islanders from fishing. There
are hundreds of other shipwrecked tankers around the world.
Back to Polluted by toxins

16. Impacts of Exxon …..

17. Eutrophication
“The enrichment of water by nutrients,
especially nitrogen and/or phosphorus,
causing an accelerated growth of algae
and higher forms of plant life to produce
an undesirable disturbance to the balance
of organisms present in the water and to
the quality of water concerned”
- OSPAR (Oslo/Paris convention for the Protection of the
Marine Environment of the North-East Atlantic)

18. Eutrophication
 Wastewater effluent (municipal and
industrial)
 Runoff and leachate from waste
disposal systems
 Runoff from agriculture/irrigation
Runoff from pasture and range
 Runoff from mines, oil fields,
unsewered industrial sites
 Overflows of combined storm and
sanitary sewers
 Untreated sewage
Sources
Contd..

19.  Over-productivity
 Reduction in phytoplankton
species diversity
 Growth of harmful algal
blooms
 Reduction in dissolved oxygen
content
 Anoxia and mass mortalities of
marine organisms
Contd..
Impacts
Eutrophication

20. Conservative pollutants - Metals
 A heavy metal is a member of a loosely-defined subset of
elements that exhibit metallic properties.
 It mainly includes the transition metals, some metalloids,
lanthanides, and actinides.
 There is an alternative term for heavy metal and is called as
toxic metal
 The major sources of metals are:
 Natural sources
 Manmade sources

21.  Erosion of ore-bearing rocks
 Atmospheric inputs - wind blown
dust
 Volcanic activity
 Forest fires
 Riverine inputs into oceans
Conservative pollutants - Metals
Contd..
Natural Sources

22.  Industrial discharge
 Sewage
 Re-suspension of sediments by dredging and trenching
Conservative pollutants - Metals
Contd..
Manmade Sources

23. Metal Natural sources
(in thousand
tonnes/year)
Anthropogenic
sources
(in thousand
tonnes/year)
Arsenic 12 18
Cadmium 1.3 7.6
Copper 28 35
Lead 12 332
Nickel 30 56
Zinc 45 132
World-wide emissions (Clark, 2001)
Conservative pollutants - Metals
Contd..

24. Arsenic (As)
 Phytoplankton most sensitive & accumulate from water
column
 Higher trophic levels accumulate via food.
Cadmium (Cd)
 Divalent cadmium is more toxic
 Tends to bioaccumulate
Lead (Pb)
 Forms strong complex with clay and suspended material
 Bioaccumulates in most marine organisms – no
significant problems.
Conservative pollutants - Metals
Contd..
Impacts

25. An example of Mercury pollution in Minamata Bay, Japan (1953-1960)
Source
Pollution from plastic plant- dumped
mercuric chloride into the bay
Impact
 Shellfishes contaminated with
mercury
 People who consumed shellfish
severely affected
 43 dead and 700 permanently
disabled
 Bay is still unusable for fishing and
shell fishing
Conservative pollutants - Metals
Contd..

26. Bioaccumulation
 Increase in concentration of a substance(s) in an organism or a
part of that organism
 The affected organism has a higher concentration of the
substance than the concentration in the organism’s
surrounding environment
 Not excreted or metabolised and failure of the target organ

27. An example of bioaccumulation in Arabic Gulf
Bioaccumulation

28.  Also called bioamplification
 Increase in concentration of a substance in a food chain,
not an organism
Biomagnification

29.  Hydrocarbons containing chlorine, fluorine, bromine or
iodine
 Differs from petroleum hydrocarbons – not degraded by
chemical oxidation or by bacteria
 Low molecular weight compounds
– eg., Dichloroethane, Freons etc.
 High molecular weight compounds
– eg., DDT, Drins, PCBs
Conservative pollutants –
Halogenated hydrocarbons

30. Aerial transport
 Aerial spraying of pesticides as aerosols – travel great
distances
Freshwater inputs
 Rain washing of pesticides carried into sea by rivers
 Silt from flood
Direct inputs
 By industrial outfalls – especially by Pesticide manufacturing
companies.
Sources
Contd..
Conservative pollutants –
Halogenated hydrocarbons

31.  Low solubility in water persist for long durations
 Fat-soluble , so incorporated into the tissue of marine
organisms and sediments
 Lethal to the animal
 Possibility of transmission through food webs – established in
a number of animals
Impacts
Contd..
Conservative pollutants –
Halogenated hydrocarbons

32. Thermal pollution
 Thermal pollution is the degradation of water quality by any
process that changes ambient water temperature.
Outfall from Qurrayah power plant, Saudi Arabia

33. Thermal pollution
Sources
 Industrial wastewater
 Power plant discharges
 Desalination plant discharges
 Urban runoff
Contd..

34.  Thermal shock
 Decrease in dissolved oxygen
 Increase in photosynthesis
 Increase in metabolic rate of fish
 Increase in oxygen consumption
Thermal pollution
Impacts
Contd..

35. Radioactive pollution
 Radioactive wastes are usually by-products of nuclear
power generation and other applications of research and
medicine.
 Radioactive waste is hazardous to human health
 Pollution due to radioactive wastes – Radioactive
pollution

36.  Weapons testing – Testing of
nuclear weapons – when
exploded underwater release
fission products and isotopes
 Liquid wastes – Discharge from
the cooling water of nuclear
reactors
 Solid wastes – Dumping of
radioactive wastes in Sea (now
no longer practiced).
Radioactive pollution
Sources
Contd..

37.  Highly lethal - Even low doses causes fatal damage
 Possibility of bioaccumulation – especially in algae and
bivalves
eg. Porphyra near a nuclear power plant location
had 10 times more caesium-137 than in the
surrounding waters
Radioactive pollution
Impacts
Contd..

38. Litter and Plastics pollution
 Marine litter, is human created
waste that has deliberately or
accidentally become afloat in a
the sea or ocean.
 It tends to accumulate at the
centre of gyres and on
coastlines, frequently washing
aground, when it is known as
beach litter or tidewrack.

39. Litter and Plastics pollution
Sources
 Up to 80% of the pollution is land-based.
 A wide variety of anthropogenic artifacts can
become marine debris
 Plastic Bags, Balloons, Buoys etc.
Contd..

40. Litter and Plastics pollution
Impacts
 Many animals that live on or in the sea consume flotsam by
mistake, as it often looks similar to their natural prey
 Blocks the passage of food and causing death through
starvation or infection.
 Tiny floating particles also resemble zooplankton, which
can lead filter feeders to consume them and cause them to
enter the ocean food chain.
 In samples taken from the North Pacific Gyre in 1999 by
the Algalita Marine Research Foundation, the mass of
plastic exceeded that of zooplankton by a factor of six.
Contd..

41. Litter and Plastics pollution

42. Plastics
• Nurdles – small pre-
production plastic
pellets
• Found in ocean and
all beaches due to
spillage
– Orange County, CA –
98% of beach debris
are nurdles

43. Quick Facts about the Ocean
 Our Planet is made up of
70% water.
 There Is
326,000,000,000,000,000,
000 gallons (326 million
trillion gallons of water
on the earth
 96% of water on the earth
is ocean water
 Fourteen billion pounds
of garbage, mostly plastic,
is dumped into the ocean
every year

44. Biological Pollution: Non-Native
Species
• Originate elsewhere, introduced by humans
intentionally or accidentally
• Outcompete and dominate native populations
• Invasive species cause extensive damage annually

45. Biological Pollution – Non-Native Species
• Caulerpa taxifolia –
tropical sea weed
– Cold-tolerant clone
introduced to
Mediterranean,
overwhelmed ecosystem
– Also in Southern
California, Australia

46. Biological Pollution – Non-Native Species
• Zebra mussel
– Invaded Great Lakes of North America
– Drove out local mussels
– Altered ecology of freshwater lakes, streams
– Blocked water pipes of industrial facilities

47. Solution to pollution
 Reduce input of toxic pollutants
 Treat sewage primary, secondary and tertiary treatment
 Ban dumping of wastes and raw sewage in the sea
 Ban ocean dumping of sludge and hazardous dredged material
 Protect sensitive areas from development, oil drilling, and oil
shipping
 Regulate coastal development

48. • Be Responsible for Your Environment………