How plastic waste gets into the ocean
Environmental scientists estimate that over one year, landlocked countries produce about 275 million tons of plastic waste. From all this quantity, 5 to 12 million tons of plastic fall into the ocean. In the United States alone, 40 to 100 thousand tons of plastic waste floats into the ocean annually. An impressive part of the garbage enters the ocean from the rivers flowing into it .
Relatively few studies are conducted on the problems of non-utilized debris entering the ocean. In addition, previously the main focus was only on coastal countries (and US states), since it was believed that they are primarily the “suppliers” of plastic for the oceans. Now, scientists have paid close attention to the amount of waste in rivers that inevitably bring their waters to the oceans.
“As far as I know, no one has yet done research on the specific ways in which garbage can enter the ocean,” says oceanographer Kara Lavender Law. “It is not yet known exactly what part of the ocean debris got into it through the rivers.”
But several studies of US river waters for the presence of plastic debris in them showed a high level of pollution. In 2011, it was discovered that each square meter of rivers flowing near California cities contains from 100 to 800 pieces of plastic not less than 5 mm in size. A study of the European Meuse River (flowing through several countries) in 2013 revealed the presence of up to 70,000 pieces of plastic per square meter, about 500 of which exceeded 25 mm in size.
The main pollution of rivers occurs with microscopic pieces of plastic. Such fragments are obtained from plastic waste exposed to solar ultraviolet radiation. In a study published this summer, it was shown that even zooplankton absorbs these pieces of plastic, as a result of which it passes through the entire food chain, right down to the person. Scientists are at a loss to say what consequences this may lead to.
In addition, very small fragments fall into the riverspolymer origin - fibers of synthetic fabrics that are washed off clothes during washing. Their submillimeter sizes do not allow you to effectively filter out these fragments during wastewater treatment, as a result of which they also enter the ocean and enter the food of the ocean inhabitants.
While decisions related to the global clean-up of ocean waters are being tested , the best that humanity can do is not to clog the planet even more. It is necessary to be more attentive to garbage and responsibly approach to its correct and effective disposal.