Walk around a supermarket and what do you see? Plastic. Shrink-wrapped cucumbers. Apples in four-packs glistening with cellophane. Chicken in a straitjacket of skintight cling film. Ranks of yogurt pots and piles of pasta packs. High-density polyethylene (HDPE) bottles of milk, and six packs of polyethylene terephthalate (PET) water bottles shrinkwrapped in another layer of, yes, plastic. Even the ground coffee, apparently virtuously bagged in brown paper, or the oh-so-rustic cardboard box of biscuits, are both lined with plastic. We’ve got a plastic addiction.

Almost everything we buy comes in a layer of plastic, but food is a serious offender.

Not so long ago we were blase about the all-pervasive packaging, tossing rustling bags of carrots next to double-wrapped pet food in our trolleys with scarcely a thought. But the "Blue Planet Effect" has seen public opinion increasingly turning against plastic, and at Cop26 the University of Portsmouth announced the formation of a new Global Plastics Policy Centre, with the aim of tackling plastic pollution. In addition, the recent report on microplastics should have given us all serious pause for thought. Given the health issues for us and for marine life, we need to consider our options.

The problem is, plastic is just too useful. It’s a wonder material, being cheap, lightweight, strong, waterproof, infinitely malleable. Since Leo Baekeland knocked out the first Bakelite – the first entirely synthetic plastic – in the laboratory in his New York home back in 1907, plastic has become intrinsic to our lives. Without it, many of the advances of modern medicine would be impossible – including the recent vaccine drive.

Plastic, then, is not the root of all evil – the issue is our love of plastic, and inability to dispose of the quantity we are producing. We are being engulfed in a tsunami of plastic waste. Professor Steve Fletcher of the University of Portsmouth pointed out: "Half of all plastic becomes waste within a year of being made and the vast majority isn’t recycled. Eleven million metric tons of plastic ends up in our oceans every year, a shocking figure which is estimated to triple to near 29 million metric tons by 2040, if nothing is done."

One of the kinds of plastics, compostable plastic, usually degrades in three to six months in an industrial composting plant, although some are safe for home composting. However they will take much longer to degrade in the sea (a year or more), and can do damage in that time, potentially fragmenting into microplastics. If accidentally added to the plastic recycling they can contaminate a batch, and in landfill they produce methane.

It’s an issue on land as well as sea. Most of our "recyclable" plastic used to be processed in China, but since 2018 they have refused to take it.

Instead it has been shipped to countries including Malaysia and Indonesia where it often festers in heaps or is burnt in highly polluting fires, rather than undergoing any form of recycling. Out of sight, out of mind.

It’s enough to raise the hackles of anyone concerned about the future of the planet. But to get to grips with the problem, we need to recognise that there are two separate issues here: plastic waste and global warming.

While there is a huge plastic pollution issue, it is mostly made as a by-product of the oil industry, so plastic’s carbon footprint compares well to the alternatives.

Take carrier bags. That cotton tote might shout your green credentials, but it is fuel-hungry to make and heavy to transport, meaning that its carbon footprint is 131 times that of a single-use plastic bag. That means, to be as good in C02 terms as using a single-use plastic bag, you would need to use the cotton bag 131 times.

Are reusable bags really greener?

Reusable bags are greener - as long as you do reuse them. It takes more energy to make and transport them, so if you chuck them or lose them after a few uses, you would have been better off with a plastic disposable.

Just how realistic is it to expect us to use a bag that many times? We’ve got used to the pristine neatness of a virgin plastic bag; that cotton bag is going to be pretty scruffy after it’s hauled home a load for the 130th time. So much for the spotless, shiny space age depicted in the movies...

Not all plastics are equal

Non-biodegradable plastics

Made as a by-product of petroleum production, it can take 400 years or more to break down. They can also disintegrate into smaller pieces, forming microplastics which accumulate in the environment.

Bioplastic

Made from plant matter, often corn starch or sugarcane. Some are compostable or biodegradable, but most will need to go into landfill. They may release less carbon than conventional plastic as they break down, but they are equally damaging to marine life.

Biodegradable plastic

Check how long it takes for the plastic to biodegrade. If it doesn’t say, it could be centuries - conventional plastic takes 400 years or more. Most biodegradable plastic is designed to break down in soil or fresh water at a temperature of 50C, which means it won’t degrade in the ocean, which is colder, and so causes as much damage to marine life as conventional plastic.

The Daily Telegraph

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