The Health Impacts of Microplastics
These small pieces pose a big risk
In today’s world, plastic is everywhere, buildings, cars, packaging, machinery – the list is nearly endless. There’s really no place you won’t find it. Despite its utility, there are a host of problems associated with plastics (1, 2). You’ve likely heard of the impact that larger pieces of discarded plastic can have – for instance plastic straws finding their way into the ocean.
Unfortunately, there are even smaller pieces of plastic in the environment that you can’t see: microplastics. Approximately 50 trillion pieces of microplastics are estimated to be currently polluting the ocean (3). They have been found in seawater, freshwater, sediment, soil, and air. Microplastics have even made their way into our food and drinks, such as beer, tap water, and sea salt (4).
So what dangers do microplastics pose? And what simple steps can you take to limit their pollution? Read on and find out!
What Are Microplastics?
Microplastics are tiny plastic particles, less than 5 millimeters long. They can be generally separated into two categories: primary microplastics and secondary microplastics (5).
Primary microplastics are plastics that were originally manufactured to be, well, micro. Already less than 5 millimeters when created, they are found in textiles, medicines, and personal care products like facial scrubs or toothpaste (4, 5). Secondary microplastics, on the other hand, are fragments of larger plastics like fishing nets or household products. This fragmentation occurs due to physical, chemical, and biological interaction with the environment such as sunlight exposure (often termed photodegradation) or wind abrasion (5).
The microplastics found in the environment today originate from both land- and ocean-based human activity. Ocean-based sources, like commercial fishing and other marine-based operations, make up about 20% of the total microplastics found while land-based sources make up the other 80%. These land-based sources, like the personal care products mentioned earlier (e.g., toothpaste, facial scrubs), air-blasting processes, microfibers from synthetic materials, and improperly disposed runoff from landfills, bleed into rivers and find their way into oceans as well (5).
The health effects of microplastics are still being studied, but there is potential for harm
Microplastics can be ingested in drinks or food, inhaled through airborne exposure, or contact with particles on skin (5-7).
For animals, especially marine organisms, ingestion of microplastics represents the largest threat. A research team has suggested that there is a correlation between poor fitness of seabirds and ingestion of plastic debris (5). Zebrafish with accumulated ingested microplastics have had altered locomotion, intestinal damage, and change in metabolic profiles (5).
Humans can ingest microplastics in beer, bottled water, even sea salt. And when marine animals ingest it from the ocean, they can act as vectors, carrying it to humans when we eat seafood (5, 7, 8).
While ingestion affects both humans and animals, airborne exposure to microplastics is becoming more worrisome to humans. We can potentially breathe in microplastics through synthetic textiles, erosion of rubber tires, or city dust (5, 6).
No matter what route they take, we know these microplastics are indeed getting into our bodies. What we don’t yet know is how long they stay, what accumulates in our systems if they do stay, and what the health effects of chronic ingestion might be. Although research is still ongoing, some potential health effects that may be linked to concentrations of ingested microplastics are metabolic disruption, immune dysfunction, neurodegenerative diseases, and chronic inflammation, which can lead to cancer (4-6).
Here’s how you can help prevent microplastic pollution
Microplastic pollution within our ecosystems may seem impossible for us to stop on an individual level. But there are ways you can reduce your contribution to pollution of microplastics as well as your personal exposure!
Drink less bottled water
Research has shown that Americans who get their recommended amount of daily water from only bottled sources have almost 20 times the exposure compared to Americans who only drink tap water (7)! So here are some simple ways to reduce exposure:
- Leave the bottled water at the store and go with the tap at home.
- Invest in a simple screw-on water purifier for the faucet if the tap water taste bugs you.
- Get a reusable (preferable glass or stainless steel) bottle for tap water on the go.
Disclaimer: if there are major health issues with your tap water (like the lead for instance), those health effects should take precedent and bottled water is okay!
Reduce your use of plastics, especially the single-use variety
Since plastics are so cheap to produce, it often makes them an ideal material for single-use disposable devices (1). Unfortunately, less than 10% of all plastic is actually recycled (10). On top of that, plastics don’t chemically degrade very well – instead they break up into smaller and smaller pieces (1, 5). Reducing your single-use plastics may seem difficult, but there are many ways to do it! Here are a few:
- Cook a few extra times a week instead of ordering takeout that comes in plastic containers.
- Leave the Ziplock bags on the shelf and store leftovers in glass containers.
- Switch to brands of tea that don’t use single-use plastic!
- Buy less packaged or processed foods in plastic packaging.
Change your laundry habits
Another large source of microplastics are microfibers, the microplastics found in synthetic fabrics, like fleece (9). Even cotton jeans and t-shirts can have a lot of synthetics blended into them! Machine washing synthetic clothing is one of the easiest ways for microplastics to find their way into the water supply. During the wash cycle, microplastics siphon off through home drains which then runs into water treatment plants that are not yet equipped to catch microplastics. Once the water is released back into the environment, pollution occurs. We’ve talked through some of the ways to limit microfibers in your laundry before, but let’s run through a few again! You can:
1. Wash with cold water and avoid delicate cycles that use high water volumes.
2. Use less detergent, and do not use bleach!
3. Fill up your machine and avoid washing bulky items like shoes with synthetic fabrics.
4. If you have the option, use a front loading washing machine! They require less water and less vigorous washing for the same cleanliness. Additionally, if you’re in the market for a new machine, you can look for those with technological improvements that can trap these particles in the future.
5. Consider getting a laundry bag or Cora ball – each of these catches microfibers so particles cannot get into the water supply.
6. Purchase clothing made of natural materials like cotton or linen – these materials don’t shed any microfibers and are often softer, more breathable, and last longer!
References:
1) https://pubmed.ncbi.nlm.nih.gov/23337043/
2) https://www.ciel.org/reports/plastic-health-the-hidden-costs-of-a-plastic-planet-february-2019/
3) https://www.sas.org.uk/our-work/plastic-pollution/plastic-pollution-facts-figures/
4) https://www.sciencedirect.com/science/article/abs/pii/S0048969719344468
5) https://www.sciencedirect.com/science/article/abs/pii/S0043135417310515
6) https://www.sciencedirect.com/science/article/abs/pii/S0269749117307686
7) https://pubs.acs.org/doi/abs/10.1021/acs.est.9b01517
8) https://link.springer.com/article/10.1007/s40572-018-0206-z