Microplastics are so pervasive they have even been discovered in the deepest known part of the ocean: the Mariana Trench.
While it has been long understood that microplastics exist on the surface of oceans, a team of researchers from four continents has found plastic waste throughout all ocean layers.
A new study, published in the journal Nature on Wednesday, collected data from 1,885 stations at various depths around the world over 10 years from 2014 to 2024.
Microplastics – tiny plastic particles less than five millimetres – are created when larger plastic products break down.
Previous studies discovered particles in Antarctic sea ice and Arctic snow, but the latest research confirms that plastic waste has invaded the depths of the planet’s oceans.
Plastic waste has been discovered in the deepest point in the world – the Mariana Trench in the Pacific Ocean. At depths of 22,000 ft, scientists found 13,500 particles per cubic metre.
“Due to their tiny size, small pieces sink very slowly and tend to distribute more evenly in the water column compared to larger macroplastics and microplastics,” Shiye Zhao, a researcher at the Japan Agency for Marine-Earth Science and Technology, told El Pais.
Zhao added: “As a result, small microplastics remain suspended in the water column for longer, increasing the likelihood of biological exposure.”
Larger pieces of plastic waste tend to fall to the ocean floor, creating a buildup.
The study also confirmed that microplastics were part of the natural carbon cycles of the oceans, which is the movement of carbon from the ocean to the atmosphere.
“Microplastics in the ocean are mostly irretrievable and persistent,” the study concluded.
A study in 2020 found that ten times more plastic debris was dumped in the Atlantic Ocean than previously believed.
Plastic pollution has been detected everywhere: in the water humans drink, in the air we breathe, in our hearts.
And, scientists have predicted that environmental contamination could double by 2040.
Although new insights into their prevalence have aided experts’ understanding of the current situation, the full scope and negative consequences of this pollution remain to be seen.
Microplastics are not only an environmental concern but also a growing health issue.
In December, Chinese researchers found that microplastics found in human organs had “alarming links” to adverse health impacts, including lesions, cervical cancer, and other diseases.
“[Microplastics] with different types, shapes, and sizes have been detected in various human systems. Notably, the occurrence of [these plastics] is markedly correlated with corresponding lesions and diseases, which is the key evidence that [they] harm human health,” the authors wrote in a study led by the Zhejiang Agriculture and Forestry University.
While the work does not establish a cause-and-effect relationship, it highlights the need for further research and methods to quantify these particles in human tissues.
