Marine Pollution. Pollution in coastal waters Coastal waters are highly affected by pollution because they are: Heavily used Close to sources of pollution.

Marine Pollution

Pollution in coastal watersCoastal waters are highly affected by pollution because they are:

Heavily usedClose to sources of pollutionShallow-water bodies Not as well circulated as the open ocean

Marine pollution: A definition

The introduction by man of substances or energy into the marine environment, which results in harm to marine life, hazards to human health, hindrance to marine activities, including fishing and other legitimate uses of the sea, impairment of quality for use of sea water and reduction of amenities. (WHO)

Main types of marine pollutionSewage sludge

DDT and PCBs

Mercury

Nuclear Radiation

Non-point-source pollution

Petroleum (oil)

Marine pollution: Sewage sludge

Sewage sludge is the semisolid material that remains after sewage treatment

Much sewage sludge was dumped offshore until laws restricted sewage dumping

Marine pollution: DDTDDT was a widely used pesticide that became concentrated in marine fish

DDT caused brown pelicans and ospreys to produce thin egg shells

Worldwide, DDT has been banned from agricultural use but is still used in limited quantities for public health purposes

Marine pollution: PCBsPCBs are industrial chemicals used as liquid coolants and insulation in industrial equipment such as power transformers

PCBs enter the marine environment through leaks and from discarded equipment

PCBs can accumulate in animal tissues and affect reproduction

Mercury and Minamata diseaseMercury has many industrial uses but is extremely toxic A chemical plant released large quantities of mercury into Minamata Bay, JapanResidents who ate highly contaminated fish suffered neurological disease and birth disorders (Minamata disease)

Nuclear RadiationCaused by leaking of containment structures

The severity of this contamination depends on the life of the radioactive isotopes that would be released if a meltdown were to occur. Some like iodine 131, would only affect humans if plants and vegetables were consumed immediately after contamination because they quickly degrade. Others, like caesium, are more dangerous because they remain radioactive for about 28 years.

Fukushima Daiichi nuclear disaster

Fukushima Daiichi nuclear power plant went into a meltdown after an earthquake and 49 foot tsunami destroyed the plant, cooling pumps, and generators on March 11, 2011

Core reactor temperatures reached over 5000◦F.

The saga continues as workers try to contain the continually leaking reactors.

Radiation’s Effects

Fukushima

Non-point- source pollutionNon-point-source pollution comes from material washed down storm drains as “poison runoff”

Includes fertilizers, pesticides, road oil, and trash

Law regulating ocean dumpingThe only substance that is illegal to dump anywhere

in the ocean is plastic

Plastic in the marine environment

Plastic:

Does not biodegrade

Floats

Has high strength

Is ingested by and entangles marine animals

Marine pollution: PetroleumOil spills can be caused by:

Tanker accidents

Intentional dumping

Drilling/pumping operations

Marine pollution: Petroleum

Petroleum is biodegradable

Many pollution experts consider oil to be among the least damaging ocean pollutants

Data from the 1989 Exxon Valdez oil spill shows the recovery of key organisms

Exxon Valdez

1989

Prince William Sound, Alaska

Hit a reef

Ship leaked 11 million gallons of oil from a tank

Some oil still left after 22 years

BP Deepwater Horizon RigApril 20, 2010

Drilling rig exploded

Gulf of Mexico (48 mi. from Mississippi River)

Over 6 million gallons so far

Huge reservoir of oil that is leaking (not as limited as ship leak)

Has entered Loop Current

Examples of damage…11 workers are presumed dead

187 turtles stranded

18 dead dolphins

Hundreds of bird nests

Pelican covered in oil, Associated Press

Dangers to Wildlife

Damage to sea grasses that hold wetlands together

Over 70% of US water birds use Lousiana’s wetlands for rest or nesting

Danger for fisheries (oysters & trout are spawning this time of year)

Harm to Florida coral reefs

Ways to Clean Up Oil Spills

Booms

Skimmers

Sorbents

Dispersants

Burning

Bacterial breakdown

Kevin Costner’s centrifuge

Various processes break up and degrade oil in the marine environment

Marine pollution: PetroleumWhen oil washes up at a beach, it can negatively affect the marine environmentOil can coat marine organisms and render their insulating fur or feathers useless

Oil on the beach from the Exxon Valdez oil spill, Alaska