Key Points
- Microplastics are increasingly contaminating humans, and have been detected in human placenta, blood, faeces and lungs
- Research on health impacts is starting, but early signs show that microplastics can be detrimental to health through cytotoxicity, oxidative stress, immune disruption, and systemic inflammation
- You can take actions to limit microplastic exposure.
Introduction
Microplastic contamination in humans is now evident. Recent lab results have found microplastics in placenta, faeces, blood and even lungs, making headlines across news outlets. We are now thought to ingest up to 5 grams of microplastics, the equivalent of one credit card, every week!
And while we’re only starting to learn about the impact on health, let no one fool you into numbness, as early research shows dramatic detrimental effects on the body. This is particularly serious as microplastic exposure is not slowing down any time soon (unless you take deliberate actions towards reducing exposure).
How do we get exposed to microplastics?
Humans are exposed to microplastics through ingestion, inhalation or skin contact.
Fig 1: Human exposure to microplastic and nanoplastic particles (source: GRID)
Ingestion happens in various ways, and can come from using plastic containers with food, especially with heat (think here about plastic cups for coffee, fancy plastic tea bags with hot water, plastic containers in microwaves). Plastic particles are leached into the food and then ingested by us. It can come from food that has been exposed to microplastic, such as seafood, and is found in salt and sugar as well.
Inhalation happens through microplastic in the air, that comes from dust, and other small plastic that is present in the environment.
Skin contact with nanoplastic from synthetic fabrics (e.g. polyester, nylon)can also lead to that plastic to be absorbed by the skin. This happens especially when these clothes are washed and heated.
Impacts on health
Research on microplastics and health is new, but early results are showing that microplastics can be detrimental to health.
Fig 2: Scientific studies focused on the effects of micro and nanoplastics on health
Usually, most of the microplastics ingested by humans are thought to be excreted. However, for very small particles (smaller than 150 μm), they can translocate from the gut cavity into the lymph and circulatory systems and pose systemic issues. Even smaller particules (<0.1 μm) can access all organs and cross the blood-brain-barrier.
Fig 3: Micro and Nano plastics in the human body
Micro- and nanoplastic interactions with the immune system may potentially lead to immunotoxicity and consequently trigger adverse effects (i.e. immunosuppression, immune activation and abnormal inflammatory responses) (L Wright et al 2017). Children in particular, when exposed to microplastics in the form of bisphenols (e.g. BPA) and phthalates can undergo profound immune disruption leading to the development of diseases (Segovia-Mendoza et al 2020).
In vitro studies show that micro- (10 μm) and nano-plastics (40–250 nm) to cause cytotoxic effects and oxidative stress at the cellular level (Schirinzi et al., 2017, Danopoulos et al 2022)
It is even thought that inflammatory bowel disease and other inflammatory issues could be triggered by mircroplastics in the gut and in the blood. Other impacts of microplastics include alteration in chromosomes which lead to infertility, obesity, and even cancer (Shivikaa et al 2017)
Research is just starting to focus on microplastics, but it is safe to say that microplastics inside our body are not harmless, and can pose real dangers to our homeostasis and cellular integrity, especially with exposure expected to increase in the future.
How to limit microplastic exposure?
There are many steps you can take to limit environmental microplastic exposure, and avoid this new health hazard.
- Avoid plastic containers: especially when exposed to heat, as that’s when most microplastics are leached. Don’t use plastic containers, especially not to heat food, avoid plastic cups for coffee and tea and instead use a glass mug (and even bring your mug to your favorite coffee / tea shop).
- Filter tap water: tap water contains microplastics, using a high quality filter will allow you to get rid of most. Avoid plastic bottles as most contain microplastics.
- Replace synthetic fabrics with natural ones: artificial fabrics such as polyester and nylon are cheap, but they leach microplastics in your environment and through your skin, especially when you use the washing machine on them. Instead replace these cheap fabrics with natural fabrics such as pure cotton, linen, and wool.
- Replace tea bags with loose leaves: A recent study has found that, when a plastic tea bag was brewed, 11.6 billion microplastics and 3.1 billion nanoplastics were released into the drink. Especially fancy looking tea bags (shiny look) which have a higer plastic content. Replace these with loose leaves that can be brewed in a proper tea pot or using tea balls.
- Focus on nose breathing: Mouth breathing allows a lot more particles to pass through the lung and stomach compared to nose breathing which has better filtration abilities. There are a dozen more reasons to nose breath, and this is another one.
Conclusion
Microplastics are a real hazard, and human exposure is expected to increase over time. Take the right actions to limit your exposure, while building up your body’s ability to detoxify and thrive so that you can handle the remaining particles gracefully.