Plastic catastrophe?

Laura lays out her lunch on her desk. The potato salad she made at home was not quite enough, so she bought some roasted vegetables and grapes at the supermarket. To wash it all down, she has a bottle of fizzy water. Yum - and so healthy! She congratulates herself on a delicious, balanced vegetarian meal.

What she does not realise is that she is also eating plastic. It comes from the bottle containing her water. It comes from the packaging of her roasted vegetables and grapes. It comes from the container she carried her potato salad in. It even comes from the board she chopped the potatoes on.

She does not realise this because the fragments are so small. She has read about microplastics, defined as any piece of plastic less than five millimetres long. But there are also nanoplastics, which are particles too small to see. Some are so tiny that they can cross the membranesA thin layer of cells that acts as a boundary or lining in an organism. between cells.

Together, the two types of plastic are known as MNPs. Scientists already knew that they could enter the body and move around it. Now, more worryingly, experiments on mice have shown that they can be carried by blood into the brain.¹

MNPs are everywhere. They have been found near the top of Mount Everest, in deserts and 36,000 feet down in the Pacific Ocean.

Around 60% of plastic produced each year is used for packaging food and drink. But during use - and particularly if it is exposed to heat or kept for a long time - it becomes worn and starts to break into MNPs.

It is estimated that the average person in the US takes in over 50,000 particles from food each year. For those who regularly drink from plastic bottles, that rises to 90,000.

A study that took blood samples from 22 people found that 17 had MNPs in their bodies. Half the samples had plastic from bottles, a third had polystyrene, and a quarter had polyethelene, from which carrier bags are made.

Babies are particularly vulnerable, because of drinking milk from plastic bottles which are heated to sterilise them. But another study found that even among those drinking breast milk, 75% were receiving MNPs.

The full consequences for human health are not yet known. But a study of fish showed that ones exposed to MNPs grew less and had fewer young - as did the next generation. Their behaviour also changed: they took more risks and consequently died younger.

"In the brain, plastic particles could increase the risk of inflammation, neurologicalRelating to the nerves and nervous system. disorders or even neurodegenerativeA type of disease which causes the cells in the nervous system to stop working. diseases such as Alzheimer's or Parkinson's," says Professor Lukas Kenner, who led the study of mice.

There are also worries that MNPs could damage the heart, lungs and gut, disrupt hormonesChemicals created inside living creatures. They are used to send messages from one part of the body to another. and increase the risk of diabetesA medical condition causing there to be too much sugar in the blood. .

To guard against this, experts advise on drinking from glass or steel water bottles, using eco-friendly packaging for food and avoiding highly processed food. You could also try to wear cotton or woollen clothes, since washing syntheticAn artificial substance or material. It is made by humans using chemical processes, rather than occurring naturally.  ones releases huge numbers of MNP microfibres into the environment.

Yes: MNPs are so prevalent that even if we bought nothing with plastic in it we could not escape them. We do not know exactly what they are doing to our bodies, but it cannot be good.  

No: We constantly come up against things that are bad for us, from germs to food, and our bodies find ways of dealing with them. Even if MNPs prove damaging, we will build up a resistance to them.

Or... Plastic may be doing us some harm, but it has also done us a huge amount of good. Packing food and drink in it makes them easier to transport and store and helps keep prices down.