New Delhi (NVI): The Atlantic Ocean contains between 12-21 million tonnes of microplastics, more than 10 times higher plastic in the ocean than previously estimated, according to a new study.
The National Oceanography Centre (NOC) study, is the first to measure concentration of invisible microplastics across the entire Atlantic — from the United Kingdom to the Falklands.
The study, published in Nature Communications, only measured the three most common types of plastic waste in the upper levels of the ocean. About 17 million tonnes of all plastic waste has entered the Atlantic Ocean over the past 65 years.
Therefore, the measured pollution from three plastic types commonly used for packaging polyethylene, polypropylene, and polystyrene — at 12 locations across a 10,000 kilometre stretch of the Atlantic Ocean.
Meanwhile, the researchers, from the UK’s National Oceanography Centre, identified up to 7,000 particles per cubic metre of sea water. They collected samples between September and November, 2016 and filtered large volumes of sea water at around 200 metres deep.
The researchers detected plastic contaminants using state-of-the-art spectroscopic imaging technique.
Moreover, the term microplastics is used to describe small plastic pieces typically smaller than 5 millimeters in diameter. Plastic is the most ubiquitous type of marine debris found in oceans and other water bodies. These debris can be of any size and shape, but those which are less than 5 mm in length (or about the size of a sesame seed) are called microplastics.
Richard Lampitt, professor from National Oceanography Centre and co-author, said, “If assumed that the concentration of microplastics measured at around 200 metres deep is representative of that in the water mass to the seafloor below with an average depth of about 3,000 metres.”
“Then the Atlantic Ocean might hold about 200 million tonnes of plastic litter in this limited polymer type and size category. This is much more than is thought to have been supplied,” he added.
At present, as much as 80 per cent of all the litter in oceans is plastic.
However, the study estimated that, more than 8 million tonnes of plastic enter the oceans every year. By 2050, the number of plastic entities would be equal to the number of fish in the sea.
-RJV
