More than 8 billion metric tonnes of plastic have been produced worldwide since 1950, enough to cover Argentina, according to the first major global analysis of mass-produced plastics.
Of this, 79 per cent (6.3 billion metric tonnes) ended up in landfills or the natural environment. Only 9 per cent was recycled while 12 per cent was incinerated.
Researchers from the University of California, Santa Barbara, led by industrial ecologist Roland Geyer, published the figures.
The largest market for plastics is packaging, which is used once and then discarded. If these trends continue, roughly 12 billion metric tonnes of plastic waste will be in landfills or the environment by 2050, according to Mr Geyer.
“What we are trying to do is to create the foundation for sustainable materials management,” Mr Geyer added. “Put simply, you can’t manage what you don’t measure, and so we think policy discussions will be more informed and fact-based now that we have these numbers.”
Unlike other materials, plastic can stay in the environment for thousands of years, he added.
In Ireland, Repak’s annual report for last year showed that total the amount of waste recovered and recycled was 794,848 tonnes, an increase of more than 32,000 tonnes (4 per cent) on the previous year.
Paper accounted for the largest volume of material recycled (49.7 per cent), followed by glass (22.2 per cent) and plastic (14.3 per cent).
Oisin Coghlan, director of Friends of the Earth Ireland, said that more than 2 million plastic bottles were not recycled in Ireland every year.
Mr Coghlan said it was “time for action to reduce plastic packaging” in Ireland which he said generates an “above average” amount of plastic waste.
“It would be better,” he said, “for us not to have plastic packaging in the first place.”
There are more than 5 trillion pieces of plastic floating in the world’s oceans, according to a 2014 study published in a Public Library of Science journal. This build-up harms marine life and ecosystems on sea and land, Mr Geyer said.