Transcript
Marine pollution
• The introduction by man, directly, or indirectly, of substancesy , y, y,or energy to the marine environment resulting in deleteriouseffects such as: hazards to human health, hindrance to marineactivities impairment of the quality of seawater for variousactivities, impairment of the quality of seawater for varioususes and reduction of amenities.
• Does not include natural processes like volcanic eruptions orearthquakes
Marine pollutantsMarine pollutants
• Agricultural run offs ((herbicides, pesticides and g (( , pnutrients)
• Sediments• Sewage (Faecal Coliform and Pathogens)• Chemicals, Metals and Radioactive Substances• Persistent toxins (PCBs, DDT, heavy metals)• Oil
l• Plastics• Energy (Thermal & light)
Sources of marine pollutionLand sourcesLand sources• 80% of non‐biological marine pollution comes from land based
activitiesi di h i di tl i t i t (• pipes discharging directly into marine waters(sewage,
industrial, chemical and food processing wastes)• Riverine flows into the sea carry pollutants from the entire catchment
area.From Air• Global atmospheric inputs to the sea from air dischargesp p gOil spills and offshore sources• Oily discharges from ballast water and bilge water during routine ship
operations and illegal dumping of solid wasteoperations and illegal dumping of solid waste• Designated dumping grounds at sea• Accidental spills from Ships carrying hazardous substances, oil, gas
etcetc.
Containing oil spills:
• Floating booms‐ contain oil and then pump intoFloating booms contain oil and then pump into other ship
• Burning oil off• Burning oil off
• Chemical dispersants
• Bioremediation‐ bacteria
Relative amts of petroleum in the ocean:
Ri ff 31 1%River runoff 31.1%Tanker operations 21.8%Coastal facilities 13 1%Coastal facilities 13.1%Atmospheric fallout 9.8%Natural seepage 9.8%p gOther transportation activities 9.8%Tanker accidents 3.3%ff h l dOffshore petroleum production 1.3%
Pesticides & Herbicides
• Designed to kill a variety of pests, such asDesigned to kill a variety of pests, such as mosquitoes, agricultural pests and weeds.
• Toxin enters food chain and effects non targeted species
• Pesticide toxicity often effects human health Rachael Carson‐ Silent Springhealth Rachael Carson Silent Spring
Bioaccumulation → biomagnification
PesticidesHalogenated hydrocarbons or organochlorines:Include DDT and PCBs, which are slow to biodegrade
Dichloro‐diphenyl‐trichloro‐ethane (DDT):d d f l• used as a pesticide from 1939‐late 1960s
• fat soluble compound th ld’ d ti h b t ti ll d d• the world’s production has substantially decreased since it was banned in the West
• detected in mud of deep sea and snow & ice of• detected in mud of deep sea and snow & ice of Antarctica
Polychloronated biphenyls (PCBs)• produced since 1944• banned in U.S. by 1979• used in production of electrical equipment• used in production of electrical equipment,
paints, plastics, adhesives, and coating compounds…compounds…
• found everywhere in the ocean• released in env. by unregulated incineration of
discarded products
DDT & PCBs affects: • copepod and oyster development• death of shrimp and a variety of fish
Toxic MetalsHg, Pb, Cd, Cu
Heavy metals resist biodegradation
Natural occurrence‐ volcanoes
• Mercury (Hg)‐ toxic when attached to short carbon‐chain alkyl group, strongly neurotoxic, birthdefects
• Lead (Pb)‐ from batteries, sewage, fuel additives, neurotoxic effects, mental development in children
• Cadmium (Cd)‐ from batteries sewage electroplating factories effects on• Cadmium (Cd)‐ from batteries, sewage, electroplating factories, effects on human kidney function, bone deformities
Heavy Metals
Minamata Disease (1953‐1960)– Japan• Industrial pollution from plastic plant; dumped
mercuric chloride into bay
• Ingestion of Hg tainted shellfish→ 43 dead and 700• Ingestion of Hg tainted shellfish → 43 dead and 700 permanently disabled
• Symptoms: kidney damage, neuromuscular deterioration, birth defects,insanity, →→ death
• Bay is still unusable for fishing and shell fishing
Cu:• Tributyl tin (antifouling paint for boats)• Banned in U.S. 1980s• Acts as an immunosuppressor• Accumulations unusually high in small whales• May be associated with strandings
Pb:• Leaded gasoline invented
1920’s• Enters water from automobile
exhaust, runoff and atmospheric fallout of industrial waste and landfills, mines, dumps
• Leaded gas banned in US in 1980’s has reduced pollution in ocean
Bioaccumulation → biomagnification
Point Source Pollution
Sewage
• Causes disease outbreaksC t ib t t t hi ti• Contributes to eutrophication
Types of Non-Point Source Types of Non-Point Source PollutionPollution
• sediments from coastal urban and i lt l d l tagricultural development
• nutrients from detergents, fertilizers, leaky septic tanks, and domesticated animals
• pesticides (home use, agricultural, & golf p ( g gcourses)
Types of Non-Point Source Types of Non-Point Source PollutionPollution
• automobile wastes such as• automobile wastes such as combusted motor oil, tire rubber, brake pad dust coolant etcbrake pad dust, coolant, etc.
• waste water from swimming pools d lt dand aquaculture ponds
Effects of marine pollution:
• Effects on sea life
• Effects on birds
• Effects on human being
– Health
– Business
• Eutrophication (process where water bodies receive excess nutrients that
stimulate excessive plant growth) and development of red tides
(phytoplankton blooms carrying red pigmentation)
• Development of oil slick: When oil is spilled on sea, it spreads over the
surface forming a thin film called OIL SLICK. Which damage marine life
Effects of marine pollution• Damages marine life to a large extent, for salt‐marsh plants, oil slicks can
affect flowering, fruiting and germination.
• Coral reefs
• If liquid oil contaminates a bird’s plumage, its water‐repellent propertiesq p g , p p pare lost, drown, die
• Drill cuttings ( broken bits of solid material) dumped on seabed createi diti & lt i th d ti f t i l hid i thanoxic conditions & result in the production of toxic sulphides in the
bottom sediment thus eliminating the benthic fauna.
• Fish and shellfish production facilities can also be affected by oil slicks• Fish and shellfish production facilities can also be affected by oil slicks.Commercial damage is tainting: imparts an unpleasant flavor to fish andseafood & is detectable even at extremely low levels of contamination.
Control measures for oil pollution
• Natural process of emulsification of oil by useof chemical dispersants: can be sprayed on thep p yoil.
• Slick‐lickers: continuous belt of absorbentSlick lickers: continuous belt of absorbentmaterial dips through the oil slick & is passedthrough rollers to extract oil.through rollers to extract oil.
• Rocks can be cleaned with high pressuresteamsteam
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