While the month celebrating the joy of Victory hits, we fight the sorrow of our Pride and Heritage being endangered with Sundarban, world’s largest mangrove forests, today in danger.
Oil slick shore. Photo right: Web
“There
is no clear relationship between the amount
of oil in the marine environment and the likely impact on wildlife. 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. Even small
spills can have very large effects. Thus, one should not merely compare
figures — the size of an oil spill is certainly not the only factor of
importance in terms of what environmental damage can be caused by the oil.”
http://oils.gpa.unep.org/facts/wildlife.htm
An oil spill is known to harm the marine life in 2
ways:
- From the Oil itself
- Chemicals used in the cleanup process
For responders working on the operation, it is essential
that they understand both the types in order to minimize the ecological impact
and respond quickly. The poisonous
chemical constituents of the oil spilled are very harmful. This can affect organisms,
both from internal exposure to oil through ingestion or inhalation and from
external exposure through the skin and eye. Oil can suffocate the fishes and
coat the feathers or furs of the birds and affect their ability to maintain
their body temperatures.
“Fuel oils, such as gasoline and diesel fuel, are very "light" oils. Light oils are very volatile (they evaporate relatively quickly), so they usually don't remain for long in the aquatic or marine environment (typically no longer than a few days). If they spread out on the water, as they do when they are accidentally spilled, they will evaporate relatively quickly.
However, while they are present, light oils present two significant hazards. First, some can ignite or explode. Second, many light oils, such as gasoline and diesel, are also considered to be toxic. They can kill animals or plants that they touch, and they are also dangerous to humans who breathe their fumes or get them on their skin.
In contrast, very "heavy" oils (like bunker oils, which are used to fuel ships) look black and may be sticky for a time until they weather sufficiently, but even then they can persist in the environment for months or even years if not removed. While these oils can be very persistent, they are generally significantly less acutely toxic than lighter oils. Instead, the short-term threat from heavy oils comes from their ability to smother organisms, whereas over the long-term, some chronic health effects like tumors may result in some organisms.” http://response.restoration.noaa.gov/oil-and-chemical-spills/oil-spills/how-oil-harms-animals-and-plants.html
The effect; how it harms the marine life?
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| Photo rights: wn.com |
On birds, the effect is often that oil destroys the feathers and skin that acts as a layer of insulation. The insulating effect of the plumage is destroyed by the oil, and the bird freezes to death (hypothermia). If a bird gets smeared with a lot of oil it may clog the bird's feathers making it impossible for it to fly. The bird may also lose its buoyancy (its ability to float on the water surface) and actually drown. The birds may inhale or ingest oil. It can further affect the reproductive system of the birds as oil from the feathers of a bird that is laying on eggs may pass through the pores in the eggshells and either kill the embryos or lead to malformations in turn, endangering the bird species.
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| Dead Dolphin. Photo rights: Dhaka Tribune |
On other living beings, including mammals, fishes and dolphins; effects of oil on marine animals depend upon species may, in addition to hypothermia, include: toxic effects and secondary organ dysfunction due to ingestion of oil can occur and affect the oral cavity, respiratory surfaces, anal and urogenital orifices. This can cause corneal abrasions, conjunctivitis and ulcers. Consumption of oil-contaminated prey could lead to the accumulation of hydrocarbons in tissues and organs.
Is there any possible Recovery?
Although we know oil spill cleanup is hazardous and a less efficient process along with the fact that wave action and photo-oxidation (from sun) helps to break oil down, but are we just going to wait for a natural selection for probably 100 years to take place and watch our pride and responsibility die?Instead, let’s have a look of what are some processes that are mostly suggested:
- Containment and recovery: Surround the oil with booms and recover the oil (for cleaning and reuse) with skimmers. This is the most widely used technique being less destructive, but it is only 10-15% efficient.
- Sorbents: Remove oil with absorbent sponges made from diaper-like substances. Local people may lend a hand by making Sorbents more available as they are also made from natural materials -- straw, grasses, coconut husks, or wood chips.
- Dispersants: These are chemicals that act like detergents to break oil up into tiny droplets to dilute the oil's effect and to provide bite-sized bits for oil-eating bacteria that occur naturally, particularly in areas that have had a history of oil spillage.
- Burning: Burning is usually 95-98% efficient, but causes black smoke. One gallon of oil burned this way creates the same pollutants as three logs in a fireplace or woodstove.
- Bioremediation: Enhancing natural biodegradation by natural oil-eating bacteria by providing them with needed fertilizers or oxygen.
References:
- Effects of Oil Pollution on Marine wildlife. Available at: http://oils.gpa.unep.org/facts/wildlife.htm (Accessed: 14 December 2014).
- How Oil Harms Animals and Plants in Marine Environments. Available at: http://response.restoration.noaa.gov/oil-and-chemical-spills/oil-spills/how-oil-harms-animals-and-plants.html (Accessed: 14 December 2014).
- Oil Spill Basics. Available at: http://www.absorbentsonline.com/oilspillbasics.htm (Accessed: 15 December 2014).
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