An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially the marine ecosystem, due to human activity, and is a form of pollution. The term is usually given to marine oil spills, where oil is released into the ocean or coastal waters, but spills may also occur on land. Oil spills may be due to releases of crude oil from tankers, offshore platforms, drilling rigs and wells, as well as spills of refined petroleum products (such as gasoline, diesel) and their by-products, heavier fuels used by large ships such as bunker fuel, or the spill of any oily refuse or waste oil.
A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the four fundamental states of matter, and is the only state with a definite volume but no fixed shape. A liquid is made up of tiny vibrating particles of matter, such as atoms, held together by intermolecular bonds. Water is, by far, the most common liquid on Earth. Like a gas, a liquid is able to flow and take the shape of a container. Most liquids resist compression, although others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly constant density. A distinctive property of the liquid state is surface tension, leading to wetting phenomena.
Petroleum is a naturally occurring, yellowish-black liquid found in geological formations beneath the Earth's surface. It is commonly refined into various types of fuels. Components of petroleum are separated using a technique called fractional distillation, i.e. separation of a liquid mixture into fractions differing in boiling point by means of distillation, typically using a fractionating column.
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons from which one hydrogen atom has been removed are functional groups called hydrocarbyls. Because carbon has 4 electrons in its outermost shell carbon has exactly four bonds to make, and is only stable if all 4 of these bonds are used.
Oil spills penetrate into the structure of the plumage of birds and the fur of mammals, reducing its insulating ability, and making them more vulnerable to temperature fluctuations and much less buoyant in the water. Cleanup and recovery from an oil spill is difficult and depends upon many factors, including the type of oil spilled, the temperature of the water (affecting evaporation and biodegradation), and the types of shorelines and beaches involved.Spills may take weeks, months or even years to clean up.
Plumage refers both to the layer of feathers that cover a bird and the pattern, colour, and arrangement of those feathers. The pattern and colours of plumage differ between species and subspecies and may vary with age classes. Within species, there can be different colour morphs. The placement of feathers on a bird is not haphazard, but rather emerge in organized, overlapping rows and groups, and these are known by standardized names.
Fur is a thick growth of hair that covers the skin of many animals. It is a defining characteristic of mammals. It consists of a combination of oily guard hair on top and thick underfur beneath. The guard hair keeps moisture and the underfur acts as an insulating blanket that keeps the animal warm.
Buoyancy or upthrust, is an upward force exerted by a fluid that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the pressure at the bottom of a column of fluid is greater than at the top of the column. Similarly, the pressure at the bottom of an object submerged in a fluid is greater than at the top of the object. The pressure difference results in a net upward force on the object. The magnitude of the force is proportional to the pressure difference, and is equivalent to the weight of the fluid that would otherwise occupy the volume of the object, i.e. the displaced fluid.
Oil spills can have disastrous consequences for society; economically, environmentally, and socially. As a result, oil spill accidents have initiated intense media attention and political uproar, bringing many together in a political struggle concerning government response to oil spills and what actions can best prevent them from happening.
Crude oil and refined fuel spills from tanker ship accidents have damaged vulnerable ecosystems in Alaska, the Gulf of Mexico, the Galapagos Islands, France, the Sundarbans, Ogoniland, and many other places. The quantity of oil spilled during accidents has ranged from a few hundred tons to several hundred thousand tons (e.g., Deepwater Horizon Oil Spill, Atlantic Empress , Amoco Cadiz ),but volume is a limited measure of damage or impact. Smaller spills have already proven to have a great impact on ecosystems, such as the Exxon Valdez oil spill because of the remoteness of the site or the difficulty of an emergency environmental response.
A tanker is a ship designed to transport or store liquids or gases in bulk. Major types of tankship include the oil tanker, the chemical tanker, and gas carrier. Tankers also carry commodities such as vegetable oils, molasses and wine. In the United States Navy and Military Sealift Command, a tanker used to refuel other ships is called an oiler but many other navies use the terms tanker and replenishment tanker.
An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment, interacting as a system. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one-another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.
Alaska is a U.S. state in the northwest extremity of North America, just across the Bering Strait from Asia. The Canadian province of British Columbia and territory of Yukon border the state to the east and southeast. Its most extreme western part is Attu Island, and it has a maritime border with Russia to the west across the Bering Strait. To the north are the Chukchi and Beaufort seas—southern parts of the Arctic Ocean. The Pacific Ocean lies to the south and southwest. It is the largest U.S. state by area and the seventh largest subnational division in the world. In addition, it is the 3rd least populous and the most sparsely populated of the 50 United States; nevertheless, it is by far the most populous territory located mostly north of the 60th parallel in North America: its population—estimated at 738,432 by the United States Census Bureau in 2015— is more than quadruple the combined populations of Northern Canada and Greenland. Approximately half of Alaska's residents live within the Anchorage metropolitan area. Alaska's economy is dominated by the fishing, natural gas, and oil industries, resources which it has in abundance. Military bases and tourism are also a significant part of the economy.
Since 2004, between 300 and 700 barrels of oil per day have been leaking from the site of an oil-production platform 12 miles off the Louisiana coast which sank in the aftermath of Hurricane Ivan. The oil spill, which officials estimate could continue throughout the 21st century, will eventually overtake the 2010 BP Deepwater Horizion disaster as the largest ever, but there are currently no efforts to cap the many leaking well heads.
Louisiana is a state in the Deep South region of the South Central United States. It is the 31st most extensive and the 25th most populous of the 50 United States. Louisiana is bordered by the state of Texas to the west, Arkansas to the north, Mississippi to the east, and the Gulf of Mexico to the south. A large part of its eastern boundary is demarcated by the Mississippi River. Louisiana is the only U.S. state with political subdivisions termed parishes, which are equivalent to counties. The state's capital is Baton Rouge, and its largest city is New Orleans.
Hurricane Ivan was a large, long-lived, Cape Verde hurricane that caused widespread damage in the Caribbean and United States. The cyclone was the ninth named storm, the sixth hurricane and the fourth major hurricane of the active 2004 Atlantic hurricane season. Ivan formed in early September, and reached Category 5 strength on the Saffir-Simpson Hurricane Scale. Ivan caused catastrophic damage to Grenada as a strong Category 3 storm, heavy damage to Jamaica as a strong Category 4 storm and then Grand Cayman, Cayman Islands and the western tip of Cuba as a Category 5 storm. After peaking in strength, the hurricane moved north-northwest across the Gulf of Mexico to strike Pensacola/Milton, Florida and Alabama as a strong Category 3 storm, causing significant damage. Ivan dropped heavy rains on the Southeastern United States as it progressed northeast and east through the eastern United States, becoming an extratropical cyclone. The remnant low from the storm moved into the western subtropical Atlantic and regenerated into a tropical cyclone, which then moved across Florida and the Gulf of Mexico into Louisiana and Texas, causing minimal damage. Ivan caused an estimated $26.1 billion along its path, of which $20.5 billion occurred in the United States.
Oil spills at sea are generally much more damaging than those on land, since they can spread for hundreds of nautical miles in a thin oil slick which can cover beaches with a thin coating of oil. These can kill seabirds, mammals, shellfish and other organisms they coat. Oil spills on land are more readily containable if a makeshift earth dam can be rapidly bulldozed around the spill site before most of the oil escapes, and land animals can avoid the oil more easily.
|Spill / Tanker||Location||Date||Tonnes of crude oil|
|Kuwaiti Oil Fires [ dubious ]||Kuwait||January 16, 1991 – November 6, 1991||136,000||1,000,000||42,000,000|
|Kuwaiti Oil Lakes||Kuwait||January 1991 – November 1991||3,409–6,818||25,000–50,000||1,050,000–2,100,000|
|Lakeview Gusher||Kern County, California, USA||March 14, 1910 – September 1911||1,200||9,000||378,000|
|Gulf War oil spill||Kuwait, Iraq, and the Persian Gulf||January 19, 1991 – January 28, 1991||818–1,091||6,000–8,000||252,000–336,000|
|Deepwater Horizon||United States, Gulf of Mexico||April 20, 2010 – July 15, 2010||560–585||4,100–4,900||172,000–180,800|
|Ixtoc I||Mexico, Gulf of Mexico||June 3, 1979 – March 23, 1980||454–480||3,329–3,520||139,818–147,840|
|Atlantic Empress / Aegean Captain||Trinidad and Tobago||July 19, 1979||287||2,105||88,396|
|Fergana Valley||Uzbekistan||March 2, 1992||285||2,090||87,780|
|Nowruz Field Platform||Iran, Persian Gulf||February 4, 1983||260||1,900||80,000|
|ABT Summer||Angola, 700 nmi (1,300 km; 810 mi) offshore||May 28, 1991||260||1,907||80,080|
|Castillo de Bellver||South Africa, Saldanha Bay||August 6, 1983||252||1,848||77,616|
|Amoco Cadiz||France, Brittany||March 16, 1978||223||1,635||68,684|
|Taylor Energy||United States, Gulf of Mexico||September 23, 2004 – Present||210–490||1,500–3,500||63,000–147,000|
An oil spill represents an immediate fire hazard. The Kuwaiti oil fires produced air pollution that caused respiratory distress.[ citation needed ] The Deepwater Horizon explosion killed eleven oil rig workers. The fire resulting from the Lac-Mégantic derailment killed 47 and destroyed half of the town's centre.[ citation needed ]
Spilled oil can also contaminate drinking water supplies. For example, in 2013 two different oil spills contaminated water supplies for 300,000 in Miri, Malaysia;80,000 people in Coca, Ecuador. In 2000, springs were contaminated by an oil spill in Clark County, Kentucky.
Contamination can have an economic impact on tourism and marine resource extraction industries. For example, the Deepwater Horizon oil spill impacted beach tourism and fishing along the Gulf Coast, and the responsible parties were required to compensate economic victims.
In general, spilled oil can affect animals and plants in two ways: dirесt from the oil and from the response or cleanup process.There is no clear relationship between the amount of oil in the aquatic environment and the likely impact on biodiversity. A smaller spill at the wrong time/wrong season and in a sensitive environment may prove much more harmful than a larger spill at another time of the year in another or even the same environment. Oil penetrates into the structure of the plumage of birds and the fur of mammals, reducing their insulating ability, and making them more vulnerable to temperature fluctuations and much less buoyant in the water.
Animals who rely on scent to find their babies or mothers cannot due to the strong scent of the oil. This causes a baby to be rejected and abandoned, leaving the babies to starve and eventually die. Oil can impair a bird's ability to fly, preventing it from foraging or escaping from predators. As they preen, birds may ingest the oil coating their feathers, irritating the digestive tract, altering liver function, and causing kidney damage. Together with their diminished foraging capacity, this can rapidly result in dehydration and metabolic imbalance. Some birds exposed to petroleum also experience changes in their hormonal balance, including changes in their luteinizing protein.The majority of birds affected by oil spills die from complications without human intervention. Some studies have suggested that less than one percent of oil-soaked birds survive, even after cleaning, although the survival rate can also exceed ninety percent, as in the case of the Treasure oil spill.
Heavily furred marine mammals exposed to oil spills are affected in similar ways. Oil coats the fur of sea otters and seals, reducing its insulating effect, and leading to fluctuations in body temperature and hypothermia. Oil can also blind an animal, leaving it defenseless. The ingestion of oil causes dehydration and impairs the digestive process. Animals can be poisoned, and may die from oil entering the lungs or liver.
There are three kinds of oil-consuming bacteria. Sulfate-reducing bacteria (SRB) and acid-producing bacteria are anaerobic, while general aerobic bacteria (GAB) are aerobic. These bacteria occur naturally and will act to remove oil from an ecosystem, and their biomass will tend to replace other populations in the food chain. The chemicals from the oil which dissolve in water, and hence are available to bacteria, are those in the water associated fraction of the oil.
In addition, oil spills can also harm air quality.The chemicals in crude oil are mostly hydrocarbons that contains toxic chemicals such as benzenes, toluene, poly-aromatic hydrocarbon and oxygenated polycyclic aromatic hydrocarbons. These chemicals can introduce adverse health effects when being inhaled into human body. In addition, these chemicals can be oxidized by oxidants in the atmosphere to form fine particulate matter after they evaporate into the atmosphere. These particulates can penetrate lungs and carry toxic chemicals into the human body. Burning surface oil can also be a source for pollution such as soot particles. During the cleanup and recovery process, it will also generate air pollutants such as nitric oxides and ozone from ships. Lastly, bubble bursting can also be a generation pathway for particulate matter during an oil spill. During the Deepwater Horizon oil spill, significant air quality issues were found on the Gulf Coast, which is the downwind of DWH oil spill. Air quality monitoring data showed that criteria pollutants had exceeded the health-based standard in the coastal regions.
A VLCC tanker can carry 2 million barrels (320,000 m3) of crude oil. This is about eight times the amount spilled in the widely known Exxon Valdez oil spill. In this spill, the ship ran aground and dumped 260,000 barrels (41,000 m3) of oil into the ocean in March 1989. Despite efforts of scientists, managers, and volunteers over 400,000 seabirds, about 1,000 sea otters, and immense numbers of fish were killed. Considering the volume of oil carried by sea, however, tanker owners' organisations often argue that the industry's safety record is excellent, with only a tiny fraction of a percentage of oil cargoes carried ever being spilled. The International Association of Independent Tanker Owners has observed that "accidental oil spills this decade have been at record low levels—one third of the previous decade and one tenth of the 1970s—at a time when oil transported has more than doubled since the mid 1980s."
Oil tankers are just one of the many sources of oil spills. According to the United States Coast Guard, 35.7% of the volume of oil spilled in the United States from 1991 to 2004 came from tank vessels (ships/barges), 27.6% from facilities and other non-vessels, 19.9% from non-tank vessels, and 9.3% from pipelines; 7.4% from mystery spills.On the other hand, only 5% of the actual spills came from oil tankers, while 51.8% came from other kinds of vessels.
The International Tanker Owners Pollution Federation has tracked 9,351 accidental spills that have occurred since 1974.According to this study, most spills result from routine operations such as loading cargo, discharging cargo, and taking on fuel oil. 91% of the operational oil spills are small, resulting in less than 7 metric tons per spill. On the other hand, spills resulting from accidents like collisions, groundings, hull failures, and explosions are much larger, with 84% of these involving losses of over 700 metric tons.
Cleanup and recovery from an oil spill is difficult and depends upon many factors, including the type of oil spilled, the temperature of the water (affecting evaporation and biodegradation), and the types of shorelines and beaches involved.Physical cleanups of oil spills are also very expensive. However, microorganisms such as Fusobacteria species demonstrate an innovative potential for future oil spill cleanup because of their ability to colonize and degrade oil slicks on the sea surface.
Methods for cleaning up include:
Equipment used includes:
Spill response procedures should include elements such as;
for spill cleanup (gloves, respirators, etc.) and an explanation of their proper use;
Environmental Sensitivity Index (ESI) maps are used to identify sensitive shoreline resources prior to an oil spill event in order to set priorities for protection and plan cleanup strategies.By planning spill response ahead of time, the impact on the environment can be minimized or prevented. Environmental sensitivity index maps are basically made up of information within the following three categories: shoreline type, and biological and human-use resources.
Shoreline type is classified by rank depending on how easy the target site would be to clean up, how long the oil would persist, and how sensitive the shoreline is.The floating oil slicks put the shoreline at particular risk when they eventually come ashore, covering the substrate with oil. The differing substrates between shoreline types vary in their response to oiling, and influence the type of cleanup that will be required to effectively decontaminate the shoreline. In 1995, the US National Oceanic and Atmospheric Administration extended ESI maps to lakes, rivers, and estuary shoreline types. The exposure the shoreline has to wave energy and tides, substrate type, and slope of the shoreline are also taken into account—in addition to biological productivity and sensitivity. The productivity of the shoreline habitat is also taken into account when determining ESI ranking. Mangroves and marshes tend to have higher ESI rankings due to the potentially long-lasting and damaging effects of both the oil contamination and cleanup actions. Impermeable and exposed surfaces with high wave action are ranked lower due to the reflecting waves keeping oil from coming onshore, and the speed at which natural processes will remove the oil.
Habitats of plants and animals that may be at risk from oil spills are referred to as "elements" and are divided by functional group. Further classification divides each element into species groups with similar life histories and behaviors relative to their vulnerability to oil spills. There are eight element groups: Birds, Reptiles, Amphibians, Fish, Invertebrates, Habitats and Plants, Wetlands, and Marine Mammals and Terrestrial Mammals. Element groups are further divided into sub-groups, for example, the ‘marine mammals’ element group is divided into dolphins, manatees, pinnipeds (seals, sea lions & walruses), polar bears, sea otters and whales.Problems taken into consideration when ranking biological resources include the observance of a large number of individuals in a small area, whether special life stages occur ashore (nesting or molting), and whether there are species present that are threatened, endangered or rare.
Human use resources are divided into four major classifications; archaeological importance or cultural resource site, high-use recreational areas or shoreline access points, important protected management areas, or resource origins.Some examples include airports, diving sites, popular beach sites, marinas, natural reserves or marine sanctuaries.
By observing the thickness of the film of oil and its appearance on the surface of the water, it is possible to estimate the quantity of oil spilled. If the surface area of the spill is also known, the total volume of the oil can be calculated.
|Film thickness||Quantity spread|
|First trace of color||0.0000060||0.0001500||150||100||1.500|
|Bright bands of color||0.0000120||0.0003000||300||200||2.900|
|Colors begin to dull||0.0000400||0.0010000||1000||666||9.700|
|Colors are much darker||0.0000800||0.0020000||2000||1332||19.500|
Oil spill model systems are used by industry and government to assist in planning and emergency decision making. Of critical importance for the skill of the oil spill model prediction is the adequate description of the wind and current fields. There is a worldwide oil spill modelling (WOSM) program.Tracking the scope of an oil spill may also involve verifying that hydrocarbons collected during an ongoing spill are derived from the active spill or some other source. This can involve sophisticated analytical chemistry focused on finger printing an oil source based on the complex mixture of substances present. Largely, these will be various hydrocarbons, among the most useful being polyaromatic hydrocarbons. In addition, both oxygen and nitrogen heterocyclic hydrocarbons, such as parent and alkyl homologues of carbazole, quinoline, and pyridine, are present in many crude oils. As a result, these compounds have great potential to supplement the existing suite of hydrocarbons targets to fine-tune source tracking of petroleum spills. Such analysis can also be used to follow weathering and degradation of crude spills.
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The Exxon Valdez oil spill occurred in Prince William Sound, Alaska, March 24, 1989, when Exxon Valdez, an oil tanker owned by Exxon Shipping Company, bound for Long Beach, California, struck Prince William Sound's Bligh Reef, 1.5 mi (2.4 km) west of Tatitlek, Alaska, at 12:04 am. local time and spilled 10.8 million US gallons (260,000 bbl) of crude oil over the next few days. It is considered to be one of the worst human-caused environmental disasters. The Valdez spill is the second largest in US waters, after the 2010 Deepwater Horizon oil spill, in terms of volume released. Prince William Sound's remote location, accessible only by helicopter, plane, or boat, made government and industry response efforts difficult and severely taxed existing response plans. The region is a habitat for salmon, sea otters, seals and seabirds. The oil, originally extracted at the Prudhoe Bay Oil Field, eventually impacted 1,300 miles (2,100 km) of coastline, of which 200 miles (320 km) were heavily or moderately oiled with an obvious impact.
The Gulf War oil spill was one of the largest oil spills in history, resulting from the Gulf War in 1991. The apparent strategic goal was to foil a potential landing by US Marines. It also made commandeering oil reserves dangerous for US forces as visibility and movement were inhibited. The immediate reports from Baghdad said that American air strikes had caused a discharge of oil from two tankers. Coalition forces determined the main source of oil to be the Sea Island terminal in Kuwait. On January 26, three US F-117 fighter-bombers destroyed pipelines to prevent further spillage into the Persian Gulf. Several other sources of oil were found to be active: tankers and a damaged Kuwaiti oil refinery near Mina Al Ahmadi, tankers near Bubiyan Island, and Iraq's Mina Al Bakr terminal.
A dispersant or a dispersing agent or a plasticizer or a superplasticizer is either a non-surface active polymer or a surface-active substance added to a suspension, usually a colloid, to improve the separation of particles and to prevent settling or clumping. Dispersants consist normally of one or more surfactants.
Petroleum is one of the main sources of energy in the World. Petroleum and its by-products are used to fuel various forms of transportation, industry and domestic electricity use. Petroleum is also used to manufacture plastics which provides products essential for daily life. Also, petroleum has helped create many products like cosmetics, tyres (rubber) pesticides etc. Over the years there has been increased concerns over the environmental effects of the petroleum industry. The environmental impacts of petroleum are mainly negative. This is due to the toxicity of petroleum which contributes to air pollution, acid rain, and various illnesses in humans. Petroleum also fuels climate change, due to the increased greenhouse gas emissions in its extraction, refinement, transport and consumption phases.
The Deepwater Horizon oil spill is an industrial disaster that began on April 20, 2010, in the Gulf of Mexico on the BP-operated Macondo Prospect, considered to be the largest marine oil spill in the history of the petroleum industry and estimated to be 8% to 31% larger in volume than the previous largest, the Ixtoc I oil spill, also in the Gulf of Mexico. The U.S. government estimated the total discharge at 4.9 million barrels. After several failed efforts to contain the flow, the well was declared sealed on September 19, 2010. Reports in early 2012 indicated that the well site was still leaking.
The Automated Data Inquiry for Oil Spills (ADIOS2) software is an oil weathering model provided by NOAA that incorporates a database containing more than a thousand crude oils and refined products, and provides quick estimates of the expected characteristics and behavior of oil spilled into the marine environment. The predictions it makes, presented as both graphics and text, are designed to help answer questions that typically arise during spill response and cleanup.
Corexit is a product line of oil dispersants used during oil spill response operations. It is produced by Nalco Holding Company, associated with BP and Exxon and an indirect subsidiary of Ecolab. Corexit was originally developed by the Standard Oil Company of New Jersey. Corexit is typically applied by aerial spraying or spraying from ships directly onto an oil slick. On contact with the dispersant, oil that would otherwise float on the surface of the water is emulsified into tiny droplets and sinks or remains suspended in the water. In theory this allows the oil to be more rapidly degraded by bacteria (bioremediation) and prevents it from accumulating on beaches and in marshes.
The following is a timeline of the Deepwater Horizon oil spill. It was a massive oil spill in the Gulf of Mexico, the largest offshore spill in U.S. history. It was a result of the well blowout that began with the Deepwater Horizon drilling rig explosion on April 20, 2010.
Following is a Timeline of the Deepwater Horizon oil spill for May 2010.
C.I.Agent Solutions is a Louisville, Kentucky-based company that specializes in environmental protection solutions. The company develops products to clean up hydrocarbon spills on land and water. Their main product is called C.I.Agent, a proprietary blend of USDA food-grade polymers that solidifies hydrocarbons.
The oil tanker Amoco Cadiz ran aground on Portsall Rocks, 5 km (3.1 mi) from the coast of Brittany, France, on 16 March 1978, and ultimately split in three and sank, all together resulting in the largest oil spill of its kind in history to that date.
An oil dispersant is a mixture of emulsifiers and solvents that helps break oil into small droplets following an oil spill. Small droplets are easier to disperse throughout a water volume, and small droplets may be more readily biodegraded by microbes in the water. Dispersant use involves a trade-off between exposing coastal life to surface oil and exposing aquatic life to dispersed oil. While submerging the oil with dispersant may lessen exposure to marine life on the surface, it increases exposure for animals dwelling underwater, who may be harmed by toxicity of both dispersed oil and dispersant. Although dispersant reduces the amount of oil that lands ashore, it may allow faster, deeper penetration of oil into coastal terrain, where it is not easily biodegraded.
The 2010 Deepwater Horizon oil spill in the Gulf of Mexico has been described as the worst environmental disaster in the United States, releasing about 4.9 million barrels of crude oil making it the largest marine oil spill. Both the spill and the cleanup efforts had effects on the environment.
The Health consequences of the Deepwater Horizon oil spill are health effects related to the explosion of the Deepwater Horizon offshore drilling rig in the Gulf of Mexico on April 20, 2010. An oil discharge continued for 84 days, resulting in the largest oil spill in the history of the petroleum industry, estimated at approximately 206 million gallons. The spill exposed thousands of area residents and cleanup workers to risks associated with oil fumes, particulate matter from controlled burns, volatile organic compounds (VOCs), polycylic aromatic hydrocarbons (PAHs), and heavy metals.
The Deepwater Horizon oil spill was discovered on the afternoon of 22 April 2010 when a large oil slick began to spread at the former rig site. According to the Flow Rate Technical Group, the leak amounted to about 4.9 million barrels of oil, exceeding the 1989 Exxon Valdez oil spill as the largest ever to originate in U.S.-controlled waters and the 1979 Ixtoc I oil spill as the largest spill in the Gulf of Mexico. BP has challenged this calculation saying that it is overestimated as it includes over 810,000 barrels of oil which was collected before it could enter the Gulf waters.
The Deepwater Horizon oil spill occurred between April 10 and September 19, 2010 in the Gulf of Mexico. A variety of techniques were used to address fundamental strategies for addressing the spilled oil, which were: to contain oil on the surface, dispersal, and removal. While most of the oil drilled off Louisiana is a lighter crude, the leaking oil was of a heavier blend which contained asphalt-like substances. According to Ed Overton, who heads a federal chemical hazard assessment team for oil spills, this type of oil emulsifies well. Once it becomes emulsified, it no longer evaporates as quickly as regular oil, does not rinse off as easily, cannot be eaten by microbes as easily, and does not burn as well. "That type of mixture essentially removes all the best oil clean-up weapons", Overton said.
The GuLF Study, or Gulf Long-term Follow-up Study, is a five-year research project examining the human-health consequences of the Deepwater Horizon oil spill in April 2010. The spill followed an explosion on a drilling rig leased by BP, the British oil company, and led to the release of over four million barrels of oil into the Gulf of Mexico, 48 miles off the coast of Louisiana in the United States.
Petroleum microbiology is a branch of microbiology that deals with the study of microorganisms that can metabolize or alter crude or refined petroleum products. These microorganisms, also called hydrocarbonoclastic microorganisms, can degrade hydrocarbons and, include a wide distribution of bacteria, methanogenic archaea, and some fungi. Not all hydrocarbonoclasic microbes depend on hydrocarbons to survive, but instead may use petroleum products as alternative carbon and energy sources. Interest in this field is growing due to the increasing role of bioremediation in oil spill cleanup.
The MT Castillo de Bellver oil spill began on 6 August 1983, when the Spanish tanker caught fire off Saldanha Bay, approximately 70 miles northwest of Cape Town, South Africa. It was carrying 250,000 tonnes of light crude oil, and was traveling through an environmentally sensitive area known for its seabird rookeries and important commercial fishing grounds. The burning vessel was abandoned and broke apart after drifting offshore. The stern capsized and sunk and the bow was sunk using explosives. A total of 145,000-170,000 tonnes of oil entered the sea. Onshore impacts were considered negligible as the slick traveled seaward. The only visible impact was the oiling of 1,500 gannets that were on a nearby island.
Oil pollution toxicity to marine fish has been observed from oil spills such as the Exxon Valdez disaster, and from nonpoint sources, such as surface runoff, which is the largest source of oil pollution in marine waters.
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