How microplastic particles are turning the oceans into plastic soup
Determining how much plastic ends up in the oceans each year is complex. Scientists often quote a 2010 estimate that the 192 countries in the world with coastlines were together responsible for about eight million tons. That is about as much as a truckload of waste being tipped into the ocean every minute of the year.
Unless there are improvements, this will be two truckloads per minute by 2030. By 2050, it will be four truckloads a minute, and by weight, the seas will contain more plastic than fish.
The contributions of each country to plastic soup vary greatly, determined primarily by population size and the presence or absence of a waste disposal infrastructure. The figure of eight million tons does not take into account what ended up in the oceans in the years before 2010, or the contributions that shipping and fishing make every year to the plastic soup. On average, about 80 percent of the plastic comes from the land and about 20 from maritime sources.
In other words, the total amount of plastic added in 2010, including from maritime sources, was ten million tons rather than eight million.
All that plastic does not degrade naturally and will remain in the environment. Cleaning up beaches and coastlines does help reduce the amount of plastic soup. Everything that washes up and is cleared away has after all been removed from the environment. The amount of plastic in the world’s seas is accumulating nevertheless: more is flowing in than is being cleared.
Although a proportion of the plastic is carried by the major ocean currents to the centers of the five subtropical gyres, the heaviest concentrations are found elsewhere. Specifically, they are found in the coastal waters off densely populated areas such as the many cities in Southeast Asia and elsewhere that are home to more than one million people. The beaches near Durban in South Africa, for example, are chock-full of plastic after every storm. Inland seas are a separate problem
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