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фильм про то как искусственный интеллект автомобиля, Millions of tonnes of nanoplastics are polluting the ocean, Tons of Invisible Plastic Pieces Lurk in Ocean Water, Millions of Tons of Tiny Plastic Particles Are Polluting the , Atlantic Ocean's Nanoplastic Problem Revealed in Shocking New , Nanoplastics Make Up Most of the Ocean’s Plastic Pollution, Study reveals the extent to which nanoplastic pollutes the , Tremendous amount of plastic floats as nanoparticles in the ocean.
Marine plastic litter tends to grab headlines, with images of suffocating seabirds or bottles washing up along coastlines. Increasingly, researchers have been finding tiny microplastic fragments across all environments, from the most densely populated cities to pristine mountaintops, as well as in human tissue including the brain and placenta. A study published today reveals yet another hidden source of this deadly waste: nanometre-scale particles are literally everywhere, says co-author Dušan Materić, an environmental analytical chemist at the Helmholtz Centre for Environmental Research in Leipzig, Germany.Materić and his colleagues sampled water at three depths representative of different environments in the North Atlantic Ocean. Throughout the water column, they found three types of nanoplastic: polyethylene terephthalate (PET), polystyrene (PS) and polyvinylchloride (PVC). These were present at average concentrations of 18 milligrams per metre cubed, which translates to 27 million tonnes of nanoplastics spread across just the top layer of the temperate to subtropical North Atlantic. “Nanoplastics make up the dominant fraction of marine plastic pollution,” Materić says. In the entire world’s oceans, it is estimated that there are around 3 million tonnes of floating plastic pollution — excluding nanoplastics.What are plastic nanoparticles and how different are they from microplastics?The tiniest of pieces of plastic, nanoplastics are defined by the researchers as having a diameter of less than one micrometre (one one-thousandth of a metre). Microplastics are between one micrometre and 5 millimetres across. At the smaller scale of nanoplastics, materials behave differently. Materić and his colleagues found that the particles were distributed throughout the water column, rather than settling to the bottom. The movement of the nanoplastic particles was dominated not by gravity, but by the random movement called Brownian motion, and by collisions with water molecules.How did the team find the nanoplastics?The scientists took water samples during a November 2020 cruise on research vessel Pelagia, which is owned by the Royal Netherlands Institute of Sea Research in Texel. They sampled at 12 locations: 5 in the system of circular currents called the North Atlantic subtropical gyre; 4 in the open ocean; and 3 from coastal areas on the European continental shelf. At each location, they gathered samples at depths of 10 metres and 1,000 metres below the surface, and then 30 metres off the ocean bottom.The nanoplastics were detected using a technology called thermal-desorption proton-transfer-reaction mass spectrometry. “We faced multiple challenges,” says Materić, including the need to remove contaminants other than nanoplastics. Each 10-millilitre sample was run through a filter with micrometre pores to clear out microplastics. Samples were then slowly heated, releasing any organic matter and allowing the remaining plastics to be identified.Not all was as expected. “We faced a big mystery,” says Materić. One major class of plastics, polyethylene (PE), was missing from the data, even though fragments almost certainly enter the ocean. The fragments probably transform into something else, or might fall to the sea bed, says Materić. “This suggests that PE nanoplastic cycling in the ocean environment follows some unusual pathway — either rapid chemical alteration or mineralization, or fast sinking.”Should we be surprised that nanoplastics are an overlooked source of plastics pollution? Should we be worried?“This does not come as a surprise to me, as I have been aware of the extent and magnitude of the problem for some time,” says Tony Walker, an environmental scientist at Dalhousie University in Halifax, Canada. “Nanoplastics, unlike microplastics, are able to pass through cell walls, meaning that they are already incorporated into the ocean phytoplankton which serve as the base of the marine food web and are able to be transferred through the marine food web,” he explains., The tiniest of pieces of plastic, nanoplastics are defined by the researchers as having a diameter of less than one micrometre (one one-thousandth of a metre)., A study published Wednesday in the journal Nature estimates the volume of nanoplastics, which are even smaller than microplastics and invisible to the naked eye, to be at least 27 million metric .
The total amount of nanoplastics — approximately 27 million tonnes — are stored in the top layer of the Northern Atlantic Ocean, up to 200 meters deep, between the temperate and subtropical zones. “This is in the same order of magnitude as the estimated mass of macro- and microplastics for the entire Atlantic,” Materić said., The analysis was clear: the ocean is swimming with nanoplastics, perhaps some 27 million tonnes when extrapolated across the whole of the North Atlantic Ocean. That's almost a tenth of the entire volume of trash thrown away in the US each year., “Nanoplastics make up the dominant fraction of marine plastic pollution,” Materić says. In the entire world’s oceans, it is estimated that there are around 3 million tonnes of floating , According to Materić, a higher concentration of nanoplastic was found in the North Atlantic subtropical gyre, an area where surface microplastics are known to accumulate because of ocean currents., Extrapolating the results from different locations to the whole of the North Atlantic Ocean, the researchers arrived at the immense amount of 27 million tons of nanoplastics., .