Oil spills include any spill of crude oil or oil distilled products (e.g., gasoline, diesel fuels, jet fuels, kerosene, Stoddard solvent, hydraulic oils, and lubricating oils) that can pollute the surface of the land, air, and water environments and living organisms, including humans, due to the environmental discharge of various organic compounds that make up crude oil and oil distillate products, the majority of which include various individual hydrocarbons.
- Oil has a lower density than water. The average density of oil is about 0.8 gm/cm3 while water is about 1.0 gm/cm3. Lower density floats on high density. As Oil is lighter than water it floats on water and prevents sunlight to pass through it. As oil floats on water, it forms a thin layer on the surface thus gradually reducing the oxygen supply to lower levels and reducing the dissolved oxygen available to plants and animals.
- Effect on Human health: Inhalation of vapor, touching oil slicks and consuming contaminated sea food may cause neurological, acute toxic effects, ocular (eye) and also problems of respiratory system. Ingestion of oil in sea food also impacts the food web. Creation of oil sinks is also a major setback.
- Effect on Economy: The second major effect of the oil spill is seen on the economy. When precious crude oil or refined petroleum is lost, it effects the amount of petroleum and gas available for use. This means more barrels have to be imported from other countries. Then comes the process of cleaning the oil spill, which requires a lot of financing.
Although the company responsible for the oil spills and their effects has to clean it up, there is a lot of government help required at this point.
Effect on Tourism Industry: The local tourism industry suffers a huge setback as most of the tourists stay away from such places. Dead birds, sticky oil and huge tar balls become common sight. Due to this, various activities such as sailing, swimming, rafting, fishing, parachute gliding cannot be performed. Industries that rely on sea water to carry on their day to day activities halt their operations till it gets cleaned.
Methods to clean oil spill: Oil Spills are very difficult to control as oil tends to spread very fast affecting a large area over shorter time. Their impact is detrimental to the subjected environment (land, water, air). Oil films retards the dissolved oxygen and decreases light penetration.
Chemical Dispersants: Oil dispersants work in the same way as dishwashing liquid. Both are made up mainly of surfactant molecules – these are molecules that have a hydrophilic (water-loving) head that is attracted to water molecules and a hydrophobic (water-hating) tail that repels water and simultaneously attaches itself to oil and grease. The result of these opposing forces is that the oil is broken up into tiny droplets suspended in water. Breaking the oil at sea into oil droplets allows them to be dispersed into the underlying sea by wave action. It is hoped that naturally occurring bacteria would then consume the droplets and the dispersant would rapidly biodegrade. Dispersants are usually applied to oil on water by spraying from surface vehicles or by applying from small fixed wing aircraft or helicopters.
Booms and skimmers: Booms contain the oil so that skimmers can collect it. Booms are floating barriers placed around the oil or whatever is leaking the oil. Skimmers can be boats, vacuum machines, sponges or oil-absorbent ropes that skim spilled oil from the water’s surface within the booms.
Leave the oil alone: Some scientists argue that oil spills should be left to disperse naturally. Oil spills are dispersed by natural physical processes in high energy environments – where strong winds, currents and wave action help to break up the oil. However, oil that reaches low-energy environments gets buried in sediments and may persist for several years.
In situ burning: Freshly spilled oil is ignited while it’s still floating on the water.