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Introduction

Pieces of plastic - everything from whole plastic objects to microscopic sized fragments - have been found in every place on Earth.  Plastic is clogging up our oceans, strangling sea creatures, filling the stomachs of animals so they starve, and getting into our bodies.  After climate change, the disposal of waste plastic is perhaps the greatest problem we face.

But plastic is also needed: right now, we can't ban it, because there are so many situations where nothing else will meet the need.  A vegetable delivery service recently provided this summary with their delivery.

WHY WE (SOMETIMES) SAY YES TO PLASTIC

Have you spotted plastic packaging in your box and wondered what it's doing there? The tricky truth about plastic is that it can play an important role in tackling food waste. Which is, after all, what we and you - are here to do.

Plastic packaging is often used to protect your veg and keep it tip top - so it ends up on your plate, and not the rubbish bin. This means you will occasionally find a bag of salad leaves or a wrapped cucumber in your box. But (and it's a big but!) this only happens when what we're rescuing has already been packaged or when the packaging is actively increasing the food's lifespan. Needless to say, we would never unpack plastic-wrapped veg only to package them up in paper.

We believe there's no better potato wrapping than a potato skin and that the plastic pollution problem is one that needs tackling urgently. But when it comes to the climate crisis, scientists have calculated that food waste should be at the top of the agenda.

Reuse

 One strategy is to take used plastic and re-process it, so that it can be used in a different way.  This inevitably degrades the plastic, so it can only be reused a few times - it is better than nothing, but it is expensive and inefficient, and can only deal with a small amount of the plastic we produce.

There is a disturbing article on ProPublica about plastic recycling and pyrolysis: The world is drowning in plastic.

Digestion

A better strategy is to break the plastic down into its component parts, which can then be used as raw 'as new' material.  Bacteria have been found which can break down some plastics, but we are only getting started with this approach, so there is a good chance that more bacteria can be found, to process more plastic and do it more efficiently and effectively.

• ‘We are just getting started’: the plastic-eating bacteria that could change the world by Stephen Buranyi