Plastic Pollution: Ocean's Perilous Predicament

Plastic pollution is a pressing issue for our oceans, with an estimated 75 to 199 million tons of plastic waste currently in the water. Every year, a further 33 billion pounds of plastic enter the marine environment, with at least one million tons of plastic entering the ocean. The plastic either breaks down into microplastic particles or floats around and forms garbage patches.

The Great Pacific Garbage Patch

There is an estimated 75 to 199 million tons of plastic waste in the ocean, with a further 33 billion pounds of plastic entering the marine environment every year. One of the most famous examples of this is the Great Pacific Garbage Patch.

Despite the common public perception of the patch existing as giant islands of floating garbage, its low density (4 particles per cubic metre) prevents detection by satellite imagery, or even by casual boaters or divers in the area. In a 2014 study, researchers sampled 1571 locations throughout the world's oceans and determined that discarded fishing gear such as buoys, lines and nets accounted for more than 60% of the mass of plastic marine debris.

Plastic waste entering the ocean

The amount of plastic waste entering the ocean each year is uncertain, with early studies estimating 8 million tonnes and more recent research suggesting between 1 million and 1.7 million tonnes. The fate of plastics once they enter the ocean has puzzled researchers, as the amount of plastic floating on the surface is significantly less. It is believed that much of the plastic breaks down into microplastic particles or forms garbage patches.

Most of the plastic in the ocean originates from land and flows downstream through rivers to the sea. Initially, it may remain in coastal waters, but it can be picked up by rotating ocean currents called gyres and transported worldwide. This is evident from the discovery of plastic from Russia, the United States, Europe, South America, Japan, and China on Henderson Island, an uninhabited isolated atoll between Chile and New Zealand.

The Great Pacific Garbage Patch is a well-known example of ocean pollution, containing 1.8 trillion pieces of plastic and covering an area twice the size of Texas. The constant influx of plastic waste into the ocean underscores the urgency of improving waste management and recycling practices to mitigate the environmental impact on marine ecosystems.

Plastic waste entering rivers and coastlines

Most of the plastic found in the ocean comes from land. It flows downstream through rivers to the sea, where it may initially stay in coastal waters. However, it can then be picked up by rotating ocean currents, called gyres, and transported anywhere in the world. This means that plastic waste entering rivers and coastlines can have a global impact.

The plastic waste entering the ocean each year is estimated to be between 1 million and 1.7 million tonnes. However, the exact figure is uncertain, with early studies producing larger estimates of around 8 million tonnes per year. The fate of plastics once they enter the ocean has been a puzzle for researchers, as the amount of plastic floating on the surface is significantly less than the amount entering the ocean.

The plastic in the ocean breaks down into microplastics or forms garbage patches. There are an estimated 50-75 trillion pieces of plastic and microplastics currently in the ocean, with some estimates ranging up to 199 million tons. This plastic pollution permeates every inch of the ocean, from the food chain to the surface. One famous example is the Great Pacific Garbage Patch, which covers an area twice the size of Texas and contains 1.8 trillion pieces of plastic.

Microplastics in the food chain

There is an estimated 75 to 199 million tons of plastic waste in the oceans, with 33 billion pounds of plastic entering the marine environment every year.

Microplastics are a significant part of this plastic waste. They are small plastic particles that can easily spread into environments affected by human activity, as well as remote areas. Microplastics have been detected in the human and animal food chain, with research focusing particularly on marine organisms.

Microplastics can enter the human food chain directly through exposure to the environment or indirectly through the transfer of MPs within the ecosystem. They are often carried by marine and terrestrial organisms that ingest them. Once in the food chain, microplastics can have adverse health effects on humans, including intestinal damage, immune problems, and neurotoxicity. They can also damage tissues and carry other toxic chemicals and microorganisms.

The presence of microplastics in the food chain poses a threat to human health and food security. It can also impact the frequency of algal blooms and increase the count of antibiotic-resistant bacteria, potentially affecting the entire food chain and posing risks to human health.

Given the risks posed by microplastics, there is a need to develop and implement standard protocols for their collection, quantification, and characterization. While there is great interest in the topic, there is still a lack of standardized procedures for the efficient extraction and analysis of microplastics, especially from sediment, air, or biological tissues.

Plastic waste from different countries

There is an estimated 75 to 199 million tons of plastic waste in the oceans, with 33 billion pounds of plastic entering the marine environment every year. Most of the plastic in the ocean comes from land, flowing downstream through rivers to the sea.

The amount of plastic waste that ends up in the ocean varies from country to country. Some countries with smaller geographical areas, longer coastlines, high rainfall, and poor waste management systems are more likely to wash plastics into the sea. For example, China generates ten times the plastic waste that Malaysia does. However, 9% of Malaysia's total plastic waste is estimated to reach the ocean, compared to 0.6% for China. The Philippines, an archipelago of over 7,000 islands with a 36,289-kilometer coastline and 4,820 plastic-emitting rivers, is estimated to emit 35% of the ocean's plastic. In addition, over 75% of the accumulated plastic in the ocean comes from the mismanaged waste in Asian countries, including India, Malaysia, China, Indonesia, Myanmar, Vietnam, Bangladesh, and Thailand.

High-income countries typically generate high amounts of plastic waste per person, but they are also better at processing it safely. In contrast, middle-income and low-income countries with developing infrastructure tend to produce a higher percentage of mismanaged waste plastic, which is more likely to find its way from land into the ocean. An estimated 4.8 to 12.7 million metric tons of plastic enter the ocean each year, and a 2017 study found that 80% of mismanaged plastic in the ocean came from just five Asian countries: China, Thailand, Vietnam, Indonesia, and the Philippines. China produced the largest quantity of plastic at 59.08 million tons of plastic waste in 2010, nearly double that of the United States, the next-highest producer, at 37.83 million tons.

Developing nations are becoming plastic pollution hotspots, and new research highlights global disparities in addressing this issue. A study by the University of Leeds found that over 52 million tons of plastic waste enters the environment annually, with 70% coming from just 20 countries, including India, Nigeria, and Indonesia, where the volume of waste has overwhelmed their ability to manage it effectively.

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