Workers sort through polyethylene terephthalate (PET) bottles holding children into their laps in a recycling factory at Mohammadpur in Dhaka. Picture: EPA
MASS production of plastics, which began just six decades ago, has accelerated so rapidly that it has created 8.3billion metric tons - most of it in disposable products that end up as trash. If that seems like an incomprehensible quantity, it is. Even the scientists who set out to conduct the world’s first tally of how much plastic has been produced, discarded, burnt or put in landfills, were horrified by the sheer size of the numbers.

“We all knew there was a rapid and extreme increase in plastic production from 1950 until now, but actually quantifying the cumulative number for all plastic ever made was quite shocking,” says Jenna Jambeck, a University of Georgia environmental engineer who specialises in studying plastic waste in the oceans.

“This kind of increase would ‘break’ any system that was not prepared for it, and this is why we have seen leakage from global waste systems into the oceans,” she says.

Plastic takes more than 400 years to degrade, so most of it still exists in some form. Only 12% has been incinerated.

The study was launched two years ago as scientists tried to get a handle on the gargantuan amount of plastic that ends up in the seas and the harm it is causing to birds, marine animals and fish. The prediction that by mid-century, the oceans will contain more plastic waste than fish, ton for ton, has become one of the most quoted statistics and a rallying cry to do something about it.

The new study, published in the peer-reviewed journal Science Advances, is the first global analysis of all plastics ever made - and their fate. Of the 8.3 billion metric tons that have been produced, 6.3 billion metric tons have become plastic waste. Of that, only 9% has been recycled. The vast majority - 79% - is accumulating in landfills or sloughing off in the natural environment as litter. That means at some point, much of it ends up in the oceans, the final sink.

If present trends continue, by 2050, there will be 12 billion metric tons of plastic in landfills. That amount is 35 000 times as heavy as the Empire State Building.

Roland Geyer, the study’s lead author, says the team of scientists are trying to create a foundation for better managing plastic products. “You can’t manage what you don’t measure,” he says. “It’s not just that we make a lot; it’s that we also make more, year after year.”

Half the resins and fibres used in plastics were produced in the past 13 years, the study found. China alone accounts for 28% of global resin and 68% of polyester polyamide and acrylic fibres.

Geyer, an engineer by training, specialises in industrial ecology as a professor at the University of California, Santa Barbara. He has studied various metals and how they’re used and managed. The rapid acceleration of plastic manufacturing, which so far has doubled roughly every 15 years, has outpaced nearly every other man-made material. It is also unlike virtually every other material. Half of all steel produced, for example, is used in construction, with a decades-long life span. Half of all manufactured plastic becomes trash in less than a year, the study found.

Much of the growth in plastic production is due to the increased use of plastic packaging, which accounts for more than 40% of nonfibre plastic.

The same team, led by Jambeck, produced the first study that assessed the amount of plastic trash that flows into the oceans annually. That research, published in 2015, estimated that 8 million metric tons of plastic end up in the oceans every year. That’s equivalent to five grocery bags of plastic trash for every foot of coastline around the globe.“We weren’t aware of the implications for plastic ending up in our environment until it was already there,” Jambeck says. “Now we have a situation where we have to come from behind to catch up. Gaining control of plastic waste is now such a large task that it calls for a comprehensive, global approach," Jambeck added. - New York Times