Recently, public attention has been attracted by photographs of huge floating islands made of plastic waste. However, an equally serious threat to the environment and human health now arises from objects completely different, much smaller in size. These are microplastic particles. According to a study in Denmark, membrane bioreactors have proven to be an effective technology to remove this invisible threat from wastewater.
About 50 trillion microplastic particles are currently floating in water bodies. These fragments of consumer goods made of plastic and industrial waste, not exceeding 5 mm in diameter, were found in four out of five samples of drinking water, 16 of 17 grades of sea salt and 80% of British mussels.
“The problem with microplastics is that it doesn’t disappear from the environment,” says Claudia Sik, biologist and project manager for the Danish NGO Plastic Change. “Plastic for a complete decomposition requires a lot of time - hundreds of years. And over this long period, particles of different sizes can harm various organisms. "
Although the effects of this on human health are unknown, there is increasing evidence that they harm animals, especially marine life.
According to Emanuel Jonques, a specialist in membrane bioreactors in Alfa Laval, research on this global problem is only just beginning, although they are talking about it more and more often. This year, the UN Environment Program launched the Clean Seas project, urging countries to take measures to ban the use of microplastic particles in cosmetics.
“The problem may be even more complicated than we think, because microplastics are very difficult to detect and measure,” says Zhonkes. Few ocean trawls were able to catch particles with a diameter of less than 0.3 mm. And for particles with a diameter of from 0.005 to less than 0.3 mm, there is still no method of quantitative assessment recognized by science. “When you filter out particles of this size, standard analysis systems find it difficult to determine whether it is plastic or another material,” says Zhonkes.
Microplastics are divided into two types of substances. These are “primary materials” used, for example, as exfoliating components in skin care products or as abrasive components of aerosols to remove paint particles and rust from the air. And "secondary materials": they are fragments formed as a result of the decay of large pieces of plastic, for example, synthetic threads, car tires and packaging.
Source - vodanews.info