What are microplastics and how are they getting inside our bodies?

Hollywood actor Orlando Bloom made headlines recently when he underwent a risky and expensive medical procedure to cleanse his blood of microplastics. But what are microplastics and how are they getting into our blood?

WHAT ARE MICROPLASTICS?
Microplastics are tiny plastic particles. These miniature pieces of plastic have either been made very small, like glitter or threads of polyester*, or have broken down from larger plastic objects.

Less than five millimetres in size, these tiny synthetic* pieces have found their way into the air, soil, food and water supplies before being ingested* into the body.

There’s evidence that they are present in human blood, reproductive cells and breast milk – and that could mean bad news for human health now and in the future.

“We’ve all got microplastics in our body and have known this for a couple of decades,” said University of Exeter ecotoxicology* expert Professor Tamara Galloway.

“We don’t yet know the implications* for human health, and microplastics need to be placed in context of the many other things that are harmful to us and that we are exposed to, such as air pollution, metals and solvents*.”

Experts have become concerned that our use of plastic products over the past 50 years has led to increased exposure.

“Plastic is a relatively new material and the word describes a group of generic* polymers* that are not all the same,” Prof Galloway said. “These big-chained molecules often have additives such as plasticisers* and dyes, and we don’t know what the impact will be for our health, but we should all try to reduce our exposure.”

HOW DO MICROPLASTICS GET INTO OUR BODIES?
Plastic enters our body when we breathe it in or ingest it while eating and drinking.

“The main route of exposure is through food and drink packaging but there’s pretty good evidence that we are also inhaling (microplastics) fibres from residues, textiles, dust and fragments in the air,” Prof Galloway said.

Whenever you breathe in dusty air, it probably contains plastic particles, she added.

WHAT DOES THIS MEAN FOR OUR HEALTH?
While heart disease* and inflammatory bowel disease* have both increased during the same time that our use of plastic has increased, there has been no direct evidence found to prove that a build-up of plastic in the body has caused these diseases.

In 2020, the World Health Organisation confirmed that there was not enough evidence to determine whether consuming or inhaling microplastics posed a risk to human health. The WHO did concede that more research was needed to “address current uncertainties”.

Dr Sabine Donnai, the CEO of the Viavi longevity clinic in London, said the fact that microplastics could cross the blood-brain barrier*, building up in brain tissue, was a cause for concern.

“Neuroinflammation* can potentially contribute to cognitive decline* and neurodegenerative* conditions like Alzheimer’s*,” she said. “And patients with microplastics-laden arterial plaques* had 4.5 times the risk of heart attack, stroke or death within three years, which may or may not be linked to microplastics.”

CAN WE RID OUR BODIES OF MICROPLASTICS?
Some plastic particles leave our bodies but what isn’t known is how many remain.

“With chemical toxicants* you can take a urine or blood sample that will give a pretty good idea of circulating levels,” Prof Galloway said. “But with microplastics you are looking at tiny solid pieces and some might be passing through the body or embedded in a tissue, so it is hard to tell.”

Plastic microparticles can cross the gut and get into the body, the bloodstream and the lymph glands*. There, the particles could be falling apart so that you might just have very small amounts or larger chunks left. Our bodies have evolved to keep harmful substances out as much as possible.

“Some are generally processed and pass out again through the urine and faeces,” Prof Galloway said. “It is perfectly possible that (the) tiniest pieces could also be sweated out through sweat glands in the body.”

“A high-fibre diet with oats, flaxseed, legumes and greens will help to bind and remove particles via the gut,” Dr Donnai added.

WHAT PLASTIC SHOULD WE AVOID?
We need to use alternatives to plastics as much as possible. Polyethylene (PE), used for making disposable food and drinks packaging, is the most common polymer found in plastic litter and in the Nature Medicine study was found to be present in human brain tissue. “Steps to reduce exposure are positive,” Prof Galloway said. “Reducing the use of single-use plastic food containers and packaging is one way of doing it.”

Dr Donnai said we should avoid heating food in plastic as heat quickens the breakdown of particles – that includes putting a plastic lid on your hot takeaway drinks – and use natural fibres, like cotton, for bedding and clothing.

“Drink filtered water if you can, as reverse osmosis* or carbon filters can drastically reduce plastic load,”

Plastic water bottles should be avoided – a study in the Proceedings of the National Academy of Sciences last year by Columbia University scientists found that a litre of bottled water contained about 240,000 tiny pieces of plastic. “Every plastic swap you take helps lighten your body’s toxic load,” Dr Donnai said.

POLL

GLOSSARY

• polyester: a synthetic fabric made from plastic thread
• synthetic: human-made
• ingested: taken into the body by swallowing, inhaling or otherwise absorbing
• ecotoxicology: a branch of science that studies the harmful effects of chemicals on ecosystems
• biosciences: branches of science that study humans, animals and plants
• implications: the conclusions that can be drawn from something
• solvents: chemicals used for dissolving other chemicals
• generic: not specifically different but general as if all plastics were the same thing
• polymers: plastic is a type of polymer. A polymer is a substance made of long chains of repeating atoms. There are also natural polymers, such as silk, rubber and cellulose
• plasticisers: a substance, usually a solvent, added to plastic to make it more flexible and less brittle
• heart disease: a range of conditions that affect the healthy functioning of the heart, including heart failure, coronary heart disease and arrhythmias
• inflammatory bowel disease: a group of conditions that cause swelling in the tissues of the digestive tract, including Crohn’s disease and Ulcerative colitis
• blood-brain barrier: a layer of cells that filters out harmful substances and keeps beneficial substances in to protect the Central Nervous System (CNS)
• Neuroinflammation: an immune response that leads to heat and swelling in your brain and CNS to fight off infection
• cognitive decline: when you start to have trouble with your memory, language and Judgement
• neurodegenerative: diseases where your nervous system starts to break down and stop working
• Alzheimer’s: a neurodegenerative disease where you lose your memory and other important mental functions
• arterial plaques: fat, calcium, cholesterol and other substances that can build up on the inside of the arteries caused by eating foods high in bad cholesterol, smoking and living a stressful lifestyle
• chemical toxicants: toxic substances
• lymph glands: part of your lymphatic system. When you are sick, your lymph fluid carries waste around your lymph vessels and your lymph nodes filter all the trapped bacteria and viruses out of your lymph fluid
• reverse osmosis: a type of water purifier that separates water molecules from other substances

EXTRA READING
Plastic not so fantastic for people
Plastic waste found in seafood
Gut play: look inside your insides in real time

QUICK QUIZ
1. What are two ways microplastics enter our body?
2. What is the most common polymer found in plastic litter that has been found in human brain tissue?
3. What should we avoid doing with plastic?
4. How many tiny pieces of plastic are in one litre of bottled water?
5. Why should you use natural fibres for clothes and bedding?

LISTEN TO THIS STORY

CLASSROOM ACTIVITIES
1. Microplastic danger
This article highlights the possible dangers we are exposing ourselves to using so many things contained in plastic. How do we alert people to these possible risks?

Create a poster, song, slogan or other measure to get the message out there that these plastics can and might be very harmful to our health.

Use the facts and information contained in the article to base your message on.

Share your work with the class.

Time: allow 25 minutes to complete this activity
Curriculum Links: English, The Arts, Health and Physical Education, Personal and Social, Critical and Creative Thinking

2. Extension
What is your biggest fear about the information contained in this Kids News article? Share your thoughts with a classmate and commit to ways you are planning on decreasing your risk.

Time: allow 10 minutes to complete this activity
Curriculum Links: English, Health and Physical Education, Personal and Social, Critical and Creative Thinking

VCOP ACTIVITY
Read this!
A headline on an article – or a title on your text – should capture the attention of the audience, telling them to read this now. So choosing the perfect words for a headline or title is very important.

Create three new headlines for the events that took place in this article. Remember, what you write and how you write it will set the pace for the whole text, so make sure it matches.

Read out your headlines to a partner and discuss what the article will be about based on the headline you created. Discuss the tone and mood you set in just your few, short words. Does it do the article justice? Will it capture the audience’s attention the way you hoped? Would you want to read more?

Consider how a headline or title is similar to using short, sharp sentences throughout your text. They can be just as important as complex ones. Go through the last text you wrote and highlight any short, sharp sentences that capture the audience.