Ocean Pollution: Understanding The Devastating Impact And Challenges

Ocean pollution is a significant environmental issue that poses a threat to the health of our planet. The oceans are the endpoint for much of the pollution we produce on land, from plastic to oil and carbon emissions. This pollution has devastating impacts on marine life and ecosystems, with plastic pollution in particular causing damage when animals come into contact with or ingest it. It is estimated that the world's oceans are polluted by roughly 171 trillion plastic particles, and this plastic waste has impacted at least 267 species worldwide. The effects of ocean pollution are felt by both marine life and humans, with microplastics and other pollutants accumulating in seafood and making it harmful for human consumption.

Marine life is harmed by ingestion, entanglement, and suffocation

Marine life is severely impacted by the presence of pollution in the ocean. One of the most significant ways marine life is harmed is through ingestion. Marine animals, particularly seabirds, often mistake small plastic fragments floating on the water's surface for food. These plastic fragments can lead to starvation or suffocation when ingested. Northern fulmars, for example, struggle to regurgitate ingested plastic. The presence of plastic in their diet has led to the species being monitored as an indicator of pellet pollution levels in the North Sea.

Furthermore, research has shown that marine animals, including fish species consumed by humans, have been found with traces of microplastics in their bodies. This issue is not limited to seabirds, as a recent study found that all seven species of sea turtles from the Atlantic and Pacific Oceans and the Mediterranean Sea had traces of microplastics in their gut. Marine apex predators, such as great white sharks and orcas, also face a significant threat from the bioaccumulation of toxic chemicals found in microplastics. As these predators are at the top of the food chain, they are exposed to high concentrations of toxins, which have been found in their fatty tissues and, in the case of orcas, their breast milk.

Another way in which marine life is harmed by ocean pollution is through entanglement. Marine debris, such as discarded fishing gear and plastic bags, can entangle marine mammals, sea turtles, and fish. This entanglement can lead to drowning, starvation, injury, and increased vulnerability to predators. For example, smaller marine animals, like sea turtles, seals, and dolphins, may drown immediately if entangled in large or heavy gear. Even if they do not drown, entangled animals may suffer physical trauma and infections from the gear cutting into their flesh. Entanglement is considered a primary cause of human-caused mortality in many whale species, and hundreds of thousands of marine mammals and sea turtles die worldwide every year due to this issue.

The final way in which ocean pollution harms marine life is through suffocation. While this has been mentioned previously in relation to ingestion, it is also a risk for marine animals that do not ingest plastic. This is because plastic debris can smother and break coral reefs, preventing their healthy growth and reducing the available habitat for marine life.

Human health is impacted by microplastics entering the food chain

Marine plastic pollution has impacted at least 267 species worldwide, including turtles, seabirds, and marine mammals. These animals often mistake plastic debris for food or become entangled in discarded plastic items such as bags and fishing nets. As plastic debris degrades, it consumes oxygen, leading to oxygen depletion in the ocean and the creation of "dead zones" where marine life cannot survive.

Plastic pollution in the ocean is largely a result of human activities, with 80% of marine debris originating from land-based sources such as litter, trash, and debris from construction, ports, marinas, and industrial facilities. The remaining 20% comes from ocean-based sources such as overboard discharges from ships and discarded fishing gear.

Microplastics, tiny plastic particles, are of particular concern due to their potential impact on human and animal health. They are widely distributed in the environment, including in the atmosphere, soil, water bodies, and the ocean. Microplastics can enter the human body through ingestion, inhalation, and skin contact, with food being a significant source of exposure.

Research has shown that microplastics can carry toxic chemicals and microorganisms, posing a range of health risks to humans. These risks include cellular toxicity, intestinal damage, immune problems, neurotoxicity, and adverse effects on the reproductive system. Additionally, microplastics have been linked to an increased likelihood of heart attacks, strokes, and even death.

Microplastics have been detected in various foodstuffs, including seafood, honey, tea, sugar, fruit, and vegetables. They can also reach farmland through sewage sludge used as fertilizer, eventually making their way into waterways. While the full extent of the health impacts is not yet known, the widespread presence of microplastics in the environment and the human body is a growing concern.

Noise pollution from commercial tankers and military sonar harms marine life

Ocean noise pollution is a pressing issue that poses a threat to marine life. Commercial tankers and military sonar devices are major contributors to this problem, with their loud and constant noises causing significant harm to marine animals.

Commercial shipping traffic is a significant source of ocean noise pollution. The large vessels that ply our oceans day and night emit sounds that can be heard underwater from tens to hundreds of miles away. These ships produce noise levels comparable to a thunderclap or a jet taking off, with the largest container ships blasting at about 190 underwater decibels or more. The constant roar of engines from these vessels disrupts the calm and harmonious sounds of the ocean, impacting marine animals' ability to communicate and navigate their environment.

Military sonar operations have been directly linked to mass whale strandings and internal injuries. In 2000, for instance, 17 beaked whales were stranded off the coast of the Bahamas following naval exercises involving mid-frequency sonar. Post-mortem examinations of these whales revealed physical trauma and internal bleeding, highlighting the devastating physiological stress caused by intense sound exposure. Sonar systems used in military naval operations emit high-intensity pulses of sound to detect submarines and map ocean floors. These loud sounds can penetrate deeper depths than shipping or industrial activities, disorienting and disrupting the behaviour of marine animals.

The impact of noise pollution on marine life is severe and far-reaching. Studies have shown that noise pollution can lead to a decline in cetacean populations, with whales and dolphins being particularly affected. These marine mammals rely on underwater sounds for essential life functions such as searching for prey, avoiding predators, locating offspring, and finding mates. Increased ambient noise masks their signals, making these vital tasks increasingly difficult.

Additionally, seismic surveys, a common practice in the search for oil and gas resources, can cause direct physical harm to marine life. The powerful sound waves generated by these surveys can exceed 230 decibels, comparable to the sound of a rocket launch. Such noise levels can cause physical damage, including bleeding from the ears and, in extreme cases, death.

The problem of ocean noise pollution demands urgent attention and mitigation strategies. While some guidelines have been implemented, such as those issued by the International Maritime Organization in 2014, more comprehensive measures are needed to protect marine life from the detrimental effects of noise pollution caused by commercial tankers and military sonar devices.

Oil spills and other pollutants create 'dead zones' with minimal oxygen

Oil spills and other pollutants have a devastating impact on marine life, creating dead zones in the ocean with minimal oxygen levels. These dead zones are areas where oxygen levels have been severely depleted, making it impossible for marine organisms to survive. The combination of oil and other pollutants, such as farm fertiliser, can have a catastrophic effect on the health of the ocean and the marine life it supports.

Oil spills occur when there is a rupture or accident involving oil tankers or rigs, and they are a significant contributor to ocean pollution. The oil spreads across the ocean surface, forming a slick that blocks sunlight and photosynthesis, which is essential for aquatic plant life. This leads to a chain reaction, as the lack of sunlight and photosynthesis affects the growth of algae, which is a crucial food source for many marine organisms.

The oil itself is toxic to some algae and can become even more poisonous when exposed to sunlight, a phenomenon known as phototoxicity. This phototoxicity played a significant role in the 1980s oil spill off Panama's coast, resulting in the death of coral and other shallow-water sea life. Oil spills also directly harm marine animals by ensnaring and suffocating them, as oil can permeate their gills.

In addition to the direct impact of oil spills, the response to these incidents can further contribute to oxygen depletion. The use of dispersants, for example, provides rich feeding for oil-eating microbes, leading to increased microbial growth. While these microbes break down the oil, they consume oxygen in the process, further depleting the already low oxygen levels in the affected areas.

Other pollutants, such as excess nitrogen and phosphorus in seawater, also contribute to oxygen depletion. As these pollutants accumulate in the ocean, they set off a chain reaction. Algae bloom and quickly die off, providing a feast for microbes that consume the oxygen needed by other marine life. This, combined with the oil and the natural gas released from ruptured wells, creates a "dead zone" where marine life struggles to survive due to the lack of oxygen.

Plastic pollution is caused by littering and improper manufacturing processes

Plastic pollution is one of the most pressing environmental issues facing the planet. It is caused by a combination of littering and improper manufacturing processes, and it is having devastating effects on marine life, human health, and ecosystems.

Littering is a significant contributor to plastic pollution in the ocean. This includes the improper disposal of disposable plastic items such as food wrappings, plastic bags, razors, bottles, and other single-use plastic products. These items often end up in waterways and eventually make their way into the ocean. Single-use plastics are responsible for 49% of all marine pollution. In addition, litter from construction, ports, marinas, commercial and industrial facilities, and trash blown out of garbage containers, trucks, and landfills also contribute to ocean plastic pollution.

Improper manufacturing processes are another major cause of plastic pollution in the ocean. This includes the production of plastics and microplastics that are not properly disposed of or recycled. Only 9% of plastic is recycled, and about 22% of plastic waste is not collected, improperly disposed of, or becomes litter. Additionally, industrial fishing contributes about 20% of the ocean's plastic pollution.

The consequences of plastic pollution are dire. Plastic can take hundreds of years to degrade, and during this time, it poses a constant threat to marine life. It has impacted at least 267 species worldwide, including sea turtles, seabirds, and marine mammals. Marine animals can become entangled in plastic debris or mistake it for food, leading to ingestion, starvation, suffocation, infection, drowning, and even death. For example, a California grey whale that washed up dead on the shores of Puget Sound was found to have plastic bags, a pair of pants, a golf ball, and other plastic items in its stomach.

Plastic pollution also affects human health. It has been found that fish and other seafood species ingest microplastics, which can accumulate in their bodies along with heavy metals and other contaminants. This contaminated seafood then enters the human food chain, posing potential risks to human health.

To address plastic pollution, it is essential to improve waste management systems, implement recycling, and reduce the use and manufacturing of unnecessary single-use plastics. Individual actions, such as reducing plastic consumption, proper disposal of plastic waste, and supporting initiatives like the Save Our Seas Act, can also make a significant difference in mitigating this pressing environmental issue.

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