The Plastic Trail to the Sea

Plastic does not simply disappear at sea — it drifts, accumulates and returns to us through the food.

Dear readers, as we continue our trail, let us now follow the journey of plastic waste from our rivers into the oceans. A significant share of the plastic polluting the world’s seas originates from just 10 countries. Topping the list is the Philippines, which is estimated to dump between 356,371 and 360,000 metric tonnes of plastic into the ocean every year.

Shockingly, Mera Mahan Bharat stands in second place. India is estimated to release between 126,513 and 130,000 metric tonnes of plastic into the ocean annually. The remaining countries in this list of the top 10 contributors are Malaysia, China, Indonesia, Myanmar, Brazil, Vietnam, Bangladesh and Thailand.

Oceans Matter

Ocean plastic pollution is a global tragedy for our seas and marine life. It is among the most pressing environmental challenges of our time, affecting nearly 900 marine species — from millions upon millions of microscopic planktonic organisms to countless sea creatures such as shrimps, prawns, lobsters and shellfish, many of which eventually form part of the seafood we consume.

It also harms both small and large fish, as well as turtles, seabirds and marine mammals, including whales, dolphins, dugongs, seals, walruses and sea lions. Yet the damage does not stop with marine life alone. Plastic pollution also introduces toxic contaminants into the food chain, ultimately reaching humans as well.

The oceans are among the most vital ecosystems on Earth, sustaining human beings and countless other living organisms, both directly and indirectly. They provide food and livelihoods to millions of people across the world, and their importance extends far beyond seafood alone. Virtually all of the planet’s plants and animals depend, in one way or another, on the global water cycle — a system driven largely by the oceans. Through the movement of water, wind and weather, the oceans help create the stable climatic conditions needed to grow crops on land and support life across ecosystems.

Breath and Balance

The ocean’s upper layers are rich in plankton — tiny algae, bacteria, seagrasses and other organisms that carry out photosynthesis and release oxygen in the process. One microscopic species of bacteria, Prochlorococcus, is so abundant that scientists estimate it produces around 20 per cent of the Earth’s oxygen. In other words, every fifth breath we take may well come from the sea.

The oceans also regulate weather patterns, absorb excess heat and trap carbon dioxide, helping to moderate the effects of climate change. Coastal ecosystems such as mangroves, seagrass meadows and salt marshes, along with coral reefs and sand dunes, act as natural barriers that protect vulnerable communities from storm surges and coastal erosion.

Together, these and many other ecosystem services provide immense environmental, social and economic benefits. Yet plastic pollution is now emerging as one of the major threats that is steadily eroding the value of these services and undermining the life-support systems that oceans provide.

Plastic Gyres

More than half of all plastic waste is less dense than water, which means it remains afloat after entering the sea. Instead of settling to the seabed, it can travel across vast distances on the ocean’s surface.

The lighter and more buoyant plastics drift far from shore, carried by winds and powerful ocean currents. Over time, they are drawn into converging current systems and gradually swept into large offshore accumulation zones, where they gather in enormous quantities.

Scientists have identified five major plastic accumulation regions in the world’s oceans. These are formed within large oceanic gyres—vast circular systems of rotating currents that trap floating marine debris and create what are often described as enormous “garbage patches”.

The five major gyres are the North Pacific Gyre, the South Pacific Gyre, the North Atlantic Gyre, the South Atlantic Gyre and the Indian Ocean Gyre. More on this in my next article. Have a nice weekend!

(The author is an environmentalist. Views personal.)