Ocean Pollution: Understanding The Plastic Crisis

Plastic in the ocean is a pressing issue that poses a threat to marine life and human health. It is estimated that there are currently 50-75 trillion pieces of plastic and microplastics in the ocean, with plastic debris found everywhere from the Arctic ice sheets to the sea floor. The primary sources of ocean plastic pollution are land-based, with rivers acting as the main arteries transporting plastic from land to sea. Once in the ocean, plastic decomposes slowly, breaking into microplastics that can be ingested by marine animals and enter the food chain, causing detrimental health effects. The accumulation of plastic in the ocean is driven by factors such as improper waste management, littering, and the abandonment of fishing gear, highlighting the urgent need for improved waste management systems and a reduction in plastic consumption.

Plastic's durability and non-biodegradability

The durability and non-biodegradability of plastics are key factors in the issue of ocean plastic pollution. Plastics are derived from petrochemicals, which are obtained from fossil fuels, crude oil, coal, or natural gas. The process of creating plastics involves heating propylene, a chemical found in petroleum, with a catalyst, which speeds up chemical reactions. This causes the individual molecules of propylene to form a polymer, a large molecule made of many small molecules strung together.

The durability of plastics is due to the strong bonds that hold these polymers together. However, this durability becomes an issue when plastics are not properly disposed of or recycled. While plastic usage and waste management infrastructures vary globally, it is estimated that only about 9-10% of plastic waste is recycled worldwide. Improper disposal and inadequate waste management contribute to the significant amount of plastic pollution in our oceans.

Plastics are known for their durability and resistance to degradation. This characteristic, which is advantageous in many applications, becomes a problem when it comes to the environment. Plastics can persist in the environment for hundreds or even thousands of years without completely biodegrading. This is because the enzymes in microorganisms that typically break down biodegradable materials do not recognize the bonds in plastic polymers. As a result, plastic waste accumulates and endures in natural environments, causing long-lasting damage to ecosystems and wildlife.

The non-biodegradability of plastics is a critical aspect of the problem. Biodegradation is a process where materials are broken down by microorganisms, resulting in the production of carbon dioxide, water, and other biological materials. This process occurs naturally in environments with sufficient oxygen, moisture, and heat, such as warm tropical forests. However, plastics, which are largely non-biodegradable, do not undergo this natural breakdown process.

While some plastics, like those made from biomass or renewable resources, are biodegradable, the majority of commonly used plastics are not. Examples of non-biodegradable plastics include polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), and polystyrene (PS). These plastics can persist in the environment for extended periods, contributing to the growing issue of ocean plastic pollution.

Sources of ocean plastic pollution

Marine plastic pollution is caused by a variety of land and ocean-based sources, with pollution sources mainly being land-based. The majority of plastic pollution in the ocean is caused by littering, with people using disposable plastic items such as food wrappings, plastic bags, razors, bottles, etc., and not disposing of them properly, which causes them to end up in the waterways and eventually in the ocean. Single-use products such as bottles, caps, cigarettes, shopping bags, cups, and straws make up a large portion of the world's plastic pollution.

Poor waste management is another major contributor to ocean plastic pollution. Continental plastic litter is flushed into the ocean by storms and river systems or is directly discharged into coastal waters. Rivers are a significant source of plastic waste in the oceans, with 1000 rivers estimated to be accountable for nearly 80% of global annual riverine plastic emissions. Small urban rivers are among the most polluting. The remaining 20% of plastic emissions are distributed across 30,000 rivers.

The agriculture sector produces a significant amount of macroplastics, such as irrigation pipes, fertilizing pellets, and containers, many of which end up in the ocean. The construction sector also generates a large amount of plastic waste, especially during large infrastructure projects.

Fishing-related debris, including abandoned fishing nets, floats, and buoys, is another significant source of ocean plastic pollution. Derelict fishing nets and other plastic debris can entangle and kill marine life. Microfibers shed from synthetic clothing or fishing nets are another problematic form of microplastic. These fibers can absorb harmful pollutants like pesticides, dyes, and flame retardants, which are then released into the ocean.

Other sources of ocean plastic pollution include stormwater runoff, industrial activities, tyre abrasion, paint shed from shipping, and sewage.

The economic costs of plastic in the ocean

The presence of plastic in the ocean has significant economic costs, which are incurred through its impact on tourism, fisheries and aquaculture, and government clean-up operations. The yearly economic costs of plastic in the ocean are estimated to be between $6-19 billion USD. The cost of environmental damage to marine ecosystems is estimated to be around $13 billion per year.

The tourism industry is another significant economic victim of marine plastic pollution. Many popular tourist destinations rely on the allure of pristine beaches, clean waters, and beachfront hotels. However, the presence of plastic litter on beaches and in the water can deter visitors, resulting in revenue losses for the local economy. For example, in South Korea, a single marine litter incident caused a revenue loss of approximately €29 million ($34 million) in a year due to a decrease in the number of tourists.

The impact of plastic in the ocean also extends to human health and food safety. Marine mammals and seabirds ingest plastic or become entangled in it, leading to injuries and mortality. It has been estimated that 60% of all seabird species have consumed plastic, and this number is predicted to increase to 99% by 2050. The presence of plastic in the ocean also contributes to the proliferation of alien invasive species, which can result in additional economic losses, although the exact figure is challenging to quantify.

The costs of dealing with plastic in the ocean are not limited to direct financial expenses but also include the opportunity cost of lost economic benefits that could have been derived from healthy marine and coastal ecosystems.

The impact on marine life and ecosystems

The impact of plastic pollution on marine life and ecosystems cannot be overstated. It is a global crisis that affects the health of marine species, food safety and quality, human health, and coastal tourism, and contributes to climate change.

Plastic in the ocean has a direct impact on marine life, from the smallest organisms to the largest creatures. Microplastics, for example, are tiny pieces of plastic that result from the breakdown of larger plastic items. These microplastics are mistaken for food by marine creatures such as sea turtles, seagulls, dolphins, and whales. Ingesting plastic can lead to perforated organs and a clogged digestive tract, causing starvation and even death. The impact of plastic ingestion is widespread, with an estimated 60% of all seabird species having consumed plastic, and this number is predicted to rise to 99% by 2050. Marine mammals also face the additional threat of entanglement in plastic debris, which has led to injuries and mortality in endangered species such as the Steller sea lion.

The Great Pacific Garbage Patch, located in the north-central Pacific Ocean between Hawaii and California, is the largest accumulation of plastic in the world. It is an area of high concentration of plastic debris, including fishing gear, buoys, eel traps, crates, nets, and consumer packaging. The impact of this garbage patch on marine life is evident, with large amounts of plastic debris found in the habitat of critically endangered Hawaiian monk seals, even in areas that serve as pup nurseries.

In addition to the direct impacts on marine life, plastic pollution also affects marine ecosystems more broadly. Plastic debris can smother and damage marine habitats, such as coral reefs and seafloor ecosystems. It can also disrupt the natural behaviour and migration patterns of marine species, as well as impact the reproductive success of certain species. For example, sea turtles may mistake floating plastic bags for jellyfish, a common prey item, leading to a reduction in their food intake and potential reproductive issues.

The impact of plastic pollution on marine life and ecosystems is a pressing issue that requires urgent global action. It is essential to address the root causes of plastic pollution, improve waste management, and promote sustainable alternatives to reduce the presence of plastic in our oceans and mitigate its harmful effects on marine life and ecosystems.

Strategies to reduce plastic usage

The presence of plastic in the ocean is a pressing global issue that requires immediate attention and action. While individual efforts are crucial, tackling this problem also necessitates a collective and global response. Here are some strategies to reduce plastic usage and mitigate plastic pollution:

• Reduce Plastic Consumption: The first step is to minimise plastic usage in daily life. This includes avoiding single-use plastics, such as plastic bags, disposable cups, plates, cutlery, and bottles. Instead, opt for reusable alternatives made from cloth, fibre, glass, or stainless steel.
• Recycling and Proper Waste Management: Recycling plays a vital role in reducing plastic waste. Familiarise yourself with the recycling process by checking the numbers on the bottom of containers and sorting them accordingly. Additionally, advocate for Extended Producer Responsibility (EPR) programs that hold manufacturers accountable for the end-of-life management of their plastic products.
• Support Innovative Solutions: Stay informed about new technologies and support initiatives that promote biodegradable plastics and plastic-eating enzymes. These innovations have the potential to address the plastic pollution problem more effectively.
• Educate and Collaborate: Educate yourself and others about plastic waste reduction strategies. Share knowledge about proper sorting and disposal practices, and the environmental impact of plastic pollution. Collaborate with recycling facilities, waste management companies, and local communities to ensure proper waste management and promote sustainable practices.
• Advocate for Policy Changes: Urge local and global leaders to implement policies that discourage plastic usage and promote sustainable alternatives. Support legislation that holds manufacturers responsible for the entire lifecycle of their plastic products.
• Refill and Reuse: Refill and reuse plastic containers whenever possible. Consider using refill shops to refill your containers with wet and dry goods. Reuse containers like old butter and ice cream tubs for various purposes, such as storing food or planting seedlings.
• Choose Alternatives: When purchasing products, opt for those with minimal or non-plastic packaging. For example, choose a glass jar of honey instead of a plastic container. When buying staples like rice and pasta, buy in bulk and store them in reusable containers at home.
• Borrow Instead of Buying: Before purchasing new items, consider borrowing them from friends or family. This reduces your consumption of plastic and saves money.

These strategies, combined with a conscious effort to reduce, reuse, recycle, and repurpose plastic items, can significantly contribute to decreasing plastic pollution and protecting our oceans and the environment.

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