Understanding oil spill, its impact and process of remediation.
Oil dispersed onto the environment either accidentally or through a natural calamity can cause a severe imbalance in the ecosystem, whether marine or otherwise. It leads to various health problems in humans and aquatic life directly through inhalation of unpleasant smells, consuming contaminated water, and penetration into the body via skin absorption.
The leakage of hydrocarbons present in the liquid petroleum releases into the environment and causes pollution. It also leads to soil contamination, human health issues, and damage to flora and fauna. Fire incidents, natural calamities, and accidental spilling during oil transportation, which might cause vessel collisions, are a few reasons for an oil spill. In addition, oil spills can cause a multitude of agricultural problems. From low crop yield to contaminated yield and lack of plant growth to plant health, oil spills have led to numerous adverse issues.
Oil spill causes hypothermia in otters and seals due to oil coating on their fur. Furthermore, oil spills cause difficulty breathing and communication for marine mammals like dolphins and whales. Oil spills are known to have spilt from vessels in the Gulf of Mexico and The Mediterranean Sea. When exposed to oil spills, humans suffer from health issues like damage to reproductive organs, respiratory and liver damage, increased cancer risk, and lower immunity. Agriculture is another area that suffers the most due to oil spills. There are various methods of oil spill cleanup using sorbents, dispersant, natural recovery, chemical stabilisation, and bioremediation are a few popular ones. However, cleaning up oil spills in extreme climatic zones like the Arctic is challenging due to the freezing temperatures, lack of infrastructure, and poor visibility.
Impact of Oil Spills
While accidents are the leading cause of oil spills that mainly occur during transit or natural calamities, their effects on marine life, birds, human health, the environment, and a country’s economy are immense. The mammals living in the water suffer from various issues, not to mention the imbalance that it causes to the ecosystem. It takes years of effort to clean up and bring the balance back. In addition, the changes in marine life bring about a lot of negative impacts on the economy, either directly or indirectly.
Aquaculture, agriculture, and contamination of drinking water are just a few areas that get affected. It is critical to consider location, local regulations, local weather conditions, and the oil spill size while deciding the suitable remediation technique. Determining whether the oil is floating at the centre of the water body or has reached the shoreline is vital to making relevant cleanup decisions. Mechanical, chemical, and bioremediation are the three main methods of oil spill remediation.
The mechanical method involves recovering oil without changing its properties through skimmers, booms, and sorbent materials. This method helps to repurpose water and reduce waste. However, this technique requires a considerable amount of investment and logistics.
The chemical method changes the chemical and physical properties of the oil. Therefore, the chemical method involves less workforce and investment. Solidifiers, burning, and dispersants are the three main chemical remediation methods.
A particular set of microbes depend on oil contaminants, pesticides, and solvents for their source of energy and food. Stimulating the growth of such microbes is a part of the bioremediation process. These helpful microbes break down the contaminants and convert them into carbon dioxide and water.
Alcanivorax borkumensis, a rod-shaped microbe, is generally found in oceans and prefers oil-polluted surfaces since hydrocarbon molecules are a part of their diet. Alkane monooxygenase, esterase, and Lipase are a few enzymes that help break the oil and begin its degradation. Oil spill takes upto fifteen years for the ecosystem to recover and remove from a minor spill. The larger ones, however, may take much longer than that.
Resins and asphaltenes are difficult to biodegrade. However, n-alkanes – branched alkanes – low molecular weight aromatics – cyclic alkanes are the first to undergo biodegradation. Alkanes combine hydrogen and carbon atoms, and bacteria help degrade alkanes. More than half the crude oil consists of alkanes. The T1B™ oil spill releases alkane hydroxylase, which helps decompose alkane.
Enzymes are a part of all living things. There are billions of them present in most cells and are a complex type of protein. Enzymes work as catalysts in biological processes. Enzymes help expedite the processes ten times faster than the original pace. Enzymes act like a working site where a weak connection forms between molecules and enzymes. Enzymes get together with the appropriate substrates and form a complex, enabling them to weaken the chemicals in the substrate and begin the degradation through catabolism and break them into simple molecules.
The transportation of oil through vessels picked up when oil demand increased across the globe. Unfortunately, like every other mode of transport, oil containers also met with accidents causing oil spills on both soil and water bodies. While the soil contamination caused a severe change in the microbial activity and led to a deterioration of crops and low yield of new ones, it also caused severe health issues to humans and aquatic life. Cleaning up an oil spill can be challenging, especially in large water bodies. Improper clean up can take decades before it returns to normalcy. Microbes and enzymes play a vital role in cleaning oil spills. While there are numerous methods of cleaning the oil spill, the first and foremost point is to avoid them in all circumstances. A more thoughtful approach would greatly help save both humans and the ecosystem.