The Deep Sea's Plastic Pollution Crisis

Plastic pollution in the ocean is a pressing environmental issue. Marine scientists have long warned of the detrimental effects of plastic waste on our oceans, aquatic life, and human health. While the exact amount of plastic in the ocean remains uncertain, it is clear that plastic pollution is widespread and persistent. Plastic debris, which constitutes 80% of all marine litter, does not fully biodegrade and can remain in the ocean indefinitely, fragmenting into microplastics over time. These microplastics, found in deep-sea sediments, can carry toxic contaminants that are transferred to humans through seafood consumption. With the ongoing challenges of plastic production and improper waste management, it is crucial to address this crisis through improved waste management, reduced plastic usage, and support for initiatives aimed at protecting our oceans and marine life.

Plastic waste makes up 80% of marine pollution

Plastic waste is the most common form of marine debris, making up 80% of all marine pollution. It is estimated that 8 to 10 million metric tons of plastic waste enter the ocean each year, with 9.5 million tons entering from land and 1.75 tons being thrown directly into the sea by the fishing and shipping industries. This plastic waste comes from a variety of land and ocean-based sources and enters the water in many ways. For example, plastic waste can enter the ocean through littering, improper disposal of trash, or rain and wind sweeping debris into water bodies. Single-use plastics, such as water bottles, takeout containers, and plastic bags, are a significant contributor to marine plastic pollution.

The impact of plastic waste on marine ecosystems is devastating. Plastic debris never fully biodegrades and can persist in the marine environment for up to 450 years, slowly fragmenting into smaller pieces called microplastics. These microplastics have become part of the food chain and have been found in drinking water, salt, beer, and even in the soil where we grow our vegetables. They are ingested by marine life, leading to fatal consequences for many species. Additionally, plastic pollution contributes to climate change as it is made from fossil fuels, and when it is incinerated, it releases carbon dioxide and methane into the atmosphere.

The deep sea is a major sink for microplastic debris, with studies suggesting that there could be up to 10,000 times more plastic particles on the seafloor than on its surface. While the exact amount of plastic on the seafloor is uncertain, it is clear that plastic pollution in the deep sea is a significant issue. Efforts to address this problem include the High Seas Treaty, which aims to turn 30% of the oceans into protected areas by 2030, and the High Ambition Coalition to End Plastic Pollution, which encourages countries to create a circular economy model for plastic.

To reduce plastic waste and its impact on the deep sea, individual behaviour changes and legislative action are both necessary. Individuals can reduce their plastic consumption, reuse and recycle plastic products, and properly dispose of waste. At the same time, supporting legislation that aims to reduce plastic use and production, improve recycling facilities, and better manage waste is crucial. By combining individual efforts with policy changes, we can work towards mitigating the devastating effects of plastic pollution on the deep sea and the wider marine environment.

Microplastics are found in deep-sea sediments

While the exact amount of plastic waste in the ocean is uncertain, it is estimated that around 0.5% of the world's plastic waste ends up in the oceans—approximately 1 to 1.7 million tonnes per year. This plastic waste never fully biodegrades and can break down into tinier pieces called microplastics, which are very small plastic particles.

Further research in the Great Australian Bight found higher microplastic counts than other analyses of deep-sea sediments, with the number of microplastic fragments increasing as surface plastic counts and seafloor slope angles increased. The study quantified microplastics in deep-sea sediments at depths ranging from 1,655 to 3,062 metres and distances of 288 to 356 kilometres from the Australian coastline. Microplastic counts ranged from 0 to 13.6 fragments per gram of dry sediment, with an average of 1.26.

The presence of microplastics in deep-sea sediments is a concerning issue, as they can be ingested by a wide range of marine species, potentially leading to physical and toxicological harm. The extent of microplastic accumulation in deep-sea sediments is not yet fully understood, but addressing this knowledge gap is crucial for predicting the distribution and potential impacts of global plastic pollution.

Mismanagement of plastic waste

The world produces around 350 million tonnes of plastic waste each year. While the exact amount of plastic waste that ends up in the ocean is uncertain, it is estimated that around 0.5% of the world's plastic waste ends up in the oceans, which equates to 1 to 2 million tonnes of plastic entering our oceans annually. This plastic waste comes from thousands of sources and enters the ocean in many ways, such as through wind and rain sweeping debris into water bodies, streams and storm drains carrying debris directly into the ocean, and littering and improper disposal of trash.

Middle-income countries, particularly in Asia, are the primary sources of plastic waste flowing into the ocean. These countries often have growing plastic consumption coupled with inadequate waste management systems, leading to challenges in dealing with the increase in consumption. Lower-income countries tend to have lower plastic emissions, as they consume less plastic. However, their local waste management infrastructure may also be lacking, leading to higher rates of mismanagement.

The mismanagement of plastic waste has severe consequences for marine ecosystems and human health. Plastic debris in the ocean does not fully biodegrade and can persist for hundreds of years. It can break down into microplastics, which can be ingested by marine organisms and enter the food chain. The toxic chemicals absorbed by plastics can also be ingested by marine life, impacting their health and the ecosystem.

To address the mismanagement of plastic waste, improvements in waste management infrastructure and practices are necessary, especially in middle- and lower-income countries. This includes investing in recycling infrastructure, proper collection and sorting of plastic waste, and implementing effective legislation to reduce littering and improper disposal of plastic waste. Additionally, reducing plastic consumption and promoting reusable alternatives can help mitigate the impact of plastic waste on the ocean.

Plastic production is expected to grow by 40% in the next decade

Plastic is the most common form of marine debris, and it is a major environmental concern. It is estimated that 0.5% of the world's plastic waste ends up in the oceans, which equates to between 1 and 2 million tonnes of plastic annually. This plastic waste in the ocean has severe consequences for marine life and ecosystems. For instance, marine animals can get entangled in plastic debris and may mistake it for food, leading to ingestion. Plastic debris can also break down into microplastics, which are tiny particles that can be found in deep-sea sediments and are challenging to remove.

Despite growing awareness and efforts to reduce plastic usage, plastic production is expected to increase by 40% in the next decade. This projected increase in plastic production is concerning given the environmental impact of plastic waste. The oil industry is heavily investing in new plastic production facilities to meet the growing demand for plastic products. This trend is driven by the symbiotic relationship between the oil industry and plastic manufacturing companies. The decrease in raw petroleum product prices, due to the expansion of the shale gas industry, has made fossil fuels more accessible and affordable, creating pressure to use them.

The projected increase in plastic production raises concerns about the potential environmental impact, especially given that plastic can take up to 450 years to decompose. While some companies are exploring biodegradable alternatives, the current recycling rate for plastic is only 9%. This means that a significant portion of the additional plastic produced will likely end up in landfills, oceans, and the environment, exacerbating the existing plastic pollution crisis.

To address this issue, it is crucial to improve the management of plastic waste and reduce plastic usage. Several nations have taken steps towards this by signing the High Seas Treaty, which aims to protect 30% of our oceans by 2030. Additionally, the UN introduced the High Ambition Coalition to End Plastic Pollution, targeting a circular economy model for plastic by 2040. These initiatives provide a glimmer of hope in the fight against plastic pollution, but more comprehensive efforts are needed to address the impending increase in plastic production.

Plastic pollution's impact on marine wildlife

Plastic pollution is a major environmental crisis that is endangering marine wildlife. While the exact amount of plastic waste in the ocean is unknown, it is estimated that around 0.5% of the world's plastic waste ends up in the oceans, with at least 8 million tonnes of plastic entering the ocean each year. This plastic waste does not decompose and can remain in the ocean indefinitely, breaking down into smaller and smaller pieces known as microplastics. These microplastics have been found in deep-sea sediments and are estimated to be up to 10,000 times more abundant on the seafloor than on the surface.

One of the most significant impacts of plastic pollution on marine wildlife is through ingestion. Many marine animals, such as sea turtles, whales, and seabirds, mistake plastic debris for food. This can lead to internal injuries, intestinal blockages, and starvation. For example, sea turtles may choke on plastic or believe they are full after ingesting it, leading to starvation. Studies have found that half of all sea turtles worldwide have ingested plastic, and plastic ingestion has been observed in 98% of sampled seabird chicks. Additionally, as plastic debris accumulates pollutants, these toxins can be transferred up the food chain to larger fish, marine mammals, and eventually human seafood eaters.

Another way plastic pollution harms marine wildlife is through entanglement. Marine animals can become entangled in plastic debris, such as abandoned fishing nets, leading to injuries, limb loss, and even death. This issue affects a wide range of marine species, from small finches to large whales. The impact of plastic pollution is widespread, with studies indicating that it has impacted at least 267 species worldwide, including 86% of all sea turtle species, 44% of seabird species, and 43% of marine mammal species.

The crisis is ongoing, with plastic production expected to increase over the next decade. While efforts are being made to address the issue, such as the High Seas Treaty and the UN's High Ambition Coalition to End Plastic Pollution, it is crucial to continue promoting proper waste management, reducing plastic consumption, and supporting initiatives to protect marine life and reduce plastic pollution.

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