Plastic has a far bigger carbon footprint than previously believed

·4-min read
Plastic pellets - most of the CO2 emissions come from plastic production (Getty)

The problem of plastic pollution in the world’s oceans is well-known - but a new study has shown that plastic has a far worse carbon footprint than previously believed.

The problem is that plastic is often made in coal-based newly industrialised countries such as China, India, Indonesia and South Africa.

The energy and process heat for the production of plastics in these countries comes primarily from the combustion of coal.

The researchers say that the global carbon footprint of plastics has doubled since 1995, reaching 2 billion tonnes of CO2 equivalent (CO2e) in 2015.

This represents more than 4.5 percent of global greenhouse gas emissions, and is more than previously thought.

Over the same period, the global health footprint of plastics from fine particulate air pollution has increased by 70 percent.

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The researchers looked at the greenhouse gas emissions generated across the life cycle of plastics - from fossil resource extraction, to processing into product classes and use, through to end of life, including recycling, incineration and landfill.

The production phase of plastics is responsible for the vast majority - 96% - of the carbon footprint of plastics.

Livia Cabernard, a doctoral student at the Institute of Science, Technology and Policy (ISTP) at ETH Zurich, says, "So far, the simplistic assumption has been that the production of plastic requires roughly the same amount of fossil fuel as is contained in the raw materials in plastic — above all petroleum," says.

"The plastics-related carbon footprint of China's transport sector, Indonesia's electronics industry and India's construction industry has increased more than 50-fold since 1995.”

"Even in a worst-case scenario in which all plastics are incinerated, their production accounts for the lion's share of total greenhouse gas and particulate matter emissions.”

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Burning plastics is causing a pollution problem on British beaches, with campaigners warning that beaches are being inundated by a form of plastic pollution which looks exactly like rocks.

The so-called ‘pyroplastics’ are believed to be remnants of plastic which has been burnt or melted, researchers say.

Hilary Rowlands, a founding member of Tywyn Beach Guardians in Gwynedd told North Wales Live, “It’s only when you pick them up, and feel how light they are, that you realise they are not stones at all,”

“There’s not a single beach I’ve combed where I haven’t come across them. Sometimes they are covered in oil or impregnated with the toxins that come from burning plastic.

“It’s all dangerous, both to the environment and the marine life.

“The longer-term concern is that they will break down into microplastics and threaten marine food chains.”

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Researchers began to analyse the ‘rocks’ in recent years after people spotted them on beaches in Cornwall - initially thinking they were real pebbles.

The lumps of plastic also weather like real rocks, and shed microplastic into the environment.

Some of the lumps could be as much as half a century old, according to Andrew Turner of the University of Plymouth.

Turner writes, ‘Pyroplastics are derived from the burning of plastic. Some may look like various burnt pieces of plastic amalgamated together, while others look remarkably like pebbles once they have been eroded down by the elements.

‘They have probably been in existence since we started burning plastic to dispose of it (perhaps 80 years or so). Some of the now restricted chemicals we find in pyroplastics suggest they have been around since at least the 1960s.

‘Burnt plastic on beaches is likely to be derived from many sources, including burning waste on the beach itself, collapse of old landfill sites, historical burning of waste at sea and contemporary burning of plastic waste on small island states.’

Pyroplastics are found worldwide, with samples having been found on Atlantic beaches in Spain and the Pacific beaches of Vancouver.

Watch: How microplastics are polluting the environment