Over 170 trillion plastic particles now pollute the world’s oceans, with scientists warning of long-term ecological damage

Global ocean plastic pollution has reached alarming levels, with researchers estimating more than 170 trillion plastic particles floating across the world’s seas. The scale of contamination, revealed through decades of international data, highlights an escalating environmental crisis that could persist for centuries.

A comprehensive study by Queen Mary University of London found that large, buoyant plastics degrade slowly at the ocean’s surface, fragmenting into microplastics over several decades. Even after a century, about 10 per cent of the original plastic mass is expected to remain at the surface, continuing to release smaller fragments into marine ecosystems.

The findings draw on records gathered between 1979 and 2019 from nearly 12,000 sampling points in the Atlantic, Pacific, and Indian Oceans, as well as the Mediterranean Sea. Scientists observed that while pollution levels fluctuated in the 1990s and early 2000s, they began to surge rapidly after 2005, reaching unprecedented concentrations in recent years.

According to the study, the total volume of ocean plastics now ranges from 82 trillion to 358 trillion particles, weighing between 1.1 million and 4.9 million tonnes. Much of this material originates from land-based sources, with an estimated 11 million metric tonnes of plastic entering the oceans each year—equivalent to more than a garbage truck’s worth every minute.

Experts caution that without urgent and coordinated global action, plastic pollution could more than double by 2040. Microplastics, in particular, pose a long-term threat as they sink slowly with marine snow to the seabed, where cold and dark conditions make degradation nearly impossible. The persistence of these materials threatens marine biodiversity, food chains, and the overall health of ocean ecosystems.

Environmental organisations have stressed the need for sweeping reforms in how plastics are produced, used, and discarded. Scientists warn that unless production and waste management systems are fundamentally restructured, the planet’s oceans will continue to bear the burden of a crisis that may take centuries to reverse.