In recent years, the ubiquity of microplastics in our environment has become a growing concern for scientists and health professionals alike. These tiny plastic particles, often invisible to the naked eye, have infiltrated nearly every aspect of our lives, from the food we eat to the air we breathe.
What are microplastics? Microplastics are plastic particles less than 5 micrometers in size . The microplastics that affect human health are very small, and not observable to the human eye — less than 700 nanometers . two main types :
Primary microplastics: Intentionally manufactured at this small size (like microbeads in cosmetics)
Secondary microplastics: Result from the breakdown of larger plastic items
Where do they come from? They often result from the breakdown of larger plastic items like water bottles or shopping bags. Some, like microbeads in cosmetics or industrial abrasives, are intentionally manufactured.
What are they made of? Various types of plastics , including:
Polyethylene (used in plastic bags) Polypropylene (used in bottle caps) Polystyrene (used in food packaging) Polyethylene terephthalate (used in water bottles) How do I get exposed to microplastics? Environmental exposure to microplastics: An overview on possible human health effects Humans are exposed to microplastics through three main routes: ingestion, inhalation, and dermal (skin) contact.
Ingestion Ingestion is considered the primary way microplastics get into our bodies . Microplastics have been detected in a wide range of food products, including seafood, drinking water (both bottled and tap), salt, sugar, and beverages like tea and coffee.
Polyethylene terephthalate (PET) and polypropylene (PP) are commonly found in bottled water, making it a significant source of microplastic ingestion.
Inhalation Inhalation is another significant exposure route . Airborne microplastics can originate from various sources, including synthetic textiles and fibers, industrial emissions, solid waste dumping sites, agricultural activities, and even sea spray in coastal areas.
Studies have shown that indoor concentrations of airborne microplastics tend to be higher than outdoor levels , raising concerns about prolonged exposure in our living and working spaces.
Through your skin Dermal contact, while less studied, is also a potential route of exposure . Cosmetics and personal care products like face creams and washes, as well as clothing and textiles, can contain microplastics. While absorption through intact skin is unlikely for larger particles, there are concerns about the potential absorption of nanoparticles.
The ubiquitous presence of microplastics in our environment means that humans are likely exposed through multiple routes on a daily basis, making it a complex and multifaceted issue to address.
How are microplastics harmful? The effects of microplastics on gut health are particularly concerning and have been the subject of increasing research. Several key areas of health impact have been identified:
Changes in your gut microbiome Studies in both animals and humans have shown that microplastics can significantly alter the composition and diversity of gut bacteria.
Microplastics can decrease beneficial bacteria while increasing potentially harmful pathogens and antibiotic-resistant microbes. This disruption of the bacterial balance in our gut could lead to digestive issues, reduced immune function, and other health problems associated with gut dysbiosis.
Physical effects on your intestines Microplastics can physically interact with and potentially damage the intestinal lining . They may increase intestinal permeability, leading to a "leaky gut" that allows more toxins and particles to enter the bloodstream.
Additionally, it’s hypothesized microplastics can adhere to intestinal walls , potentially trapping fat molecules and increasing fat absorption.
Microplastics migrating to other organs Alarmingly, research has shown that microplastics can move beyond the gut. Studies in mice demonstrated that microplastics migrated from the intestines into the liver, kidneys, and even the brain after just four weeks of exposure.
This suggests that the impact of microplastics may extend far beyond the digestive system, potentially affecting multiple organ systems.
Inflammatory responses Microplastics may trigger inflammatory responses and oxidative stress in the gut. Research has shown they can cause intestinal cells to release inflammatory molecules, and the oxidative stress induced by microplastics could potentially damage gut tissues over time.
Are microplastics the same thing as forever chemicals? No!
“Forever chemicals”, or PFAS (per- and polyfluoroalkyl substances) are a different type of environmental contaminant that is proving to be harmful to health. PFAS are a group of man-made chemicals, not necessarily related to plastics.
There are thousands of different PFAS compounds. They contain incredibly strong carbon-fluorine bonds, making them extremely resistant to breaking down in the environment or in our bodies.
Key differences and why they matter Form:
Microplastics are solid particles you might see under a microscope.
PFAS are chemical compounds you can't see with the naked eye.
Persistence:
Both stick around in the environment, but PFAS take it to another level. Their "forever chemical" nickname isn't an exaggeration.
Sources:
Microplastics often come from everyday consumer products and plastic waste.
PFAS come primarily from industrial sources and specialized consumer products.
Health Concerns:
Microplastics: Research is ongoing, but there are concerns about their potential to carry other pollutants and their physical effects on organisms.
PFAS: Have been linked to specific health issues, including effects on the immune system, thyroid function, and potential cancer risks.
Environmental Behavior:
Microplastics can float, sink, or be carried by currents in water bodies.
PFAS can dissolve in water and travel long distances through water and air.
In an unexpected turn, microplastics can actually adsorb (attach to their surface) PFAS, potentially acting as a delivery system for these chemicals in the environment.
Regulation:
PFAS: Due to their known toxicity, several PFAS compounds are more heavily regulated.
Microplastics: Regulations are still evolving, with initial focus on banning intentionally added microplastics in products.
How can I understand my level of exposure to microplastics? For most people, it’s not worth worrying about your exact level of microplastic exposure — energy is better spent trying to reduce your overall microplastic exposure. No one living in the United States is free of exposure to microplastics.
If you have to know — Million Marker offers a direct-to-consumer blood test that allows you to measure how many of the common chemicals plastics emit are also in your blood—bisphenols and phthalates . You won’t know how much plastic is inside you, but you can get a sense for how severe your exposure has been by the levels of these chemicals inside of your body relative to safe levels.
One test is $299 and is available for purchase at millionmarker.com .
How can I avoid microplastics? Filter or boil your drinking water You can use a high-quality water filter, like a reverse-osmosis filter, to remove microplastics from tap water.
These high quality water filters can be expensive — but boiling your water also removes up to 90% of microplastics , too.
Avoid single-use plastics Reducing your use of disposable plastic items like water bottles, straws, and food packaging is an easy way to reduce your microplastics exposure.
For most people, the biggest source of single-use plastic is from processed foods. Whole foods are less likely to be contaminated with microplastics from packaging.
Several groups done independent testing of different packaged foods for microplastic contamination.
Still, eating food packaged in glass or cardboard is not a magic bullet — microplastic contamination is so pervasive throughout the food supply chain that it may have been contaminated with plastics long before it ever reached the glass bottle you bought it in.
One study tried to control microplastic content of food to see if interventions like glass containers would reduce total exposures. For 5 days, 10 families had all of their food prepared to minimize microplastic exposure.
Alarmingly, the amount of microplastics in their urine increased after this intervention. The culprit? The glass bottled milk, which most likely went through plastic tubing as a part of the packaging and pasteurization process.
Choose natural fabrics Clothing can be a microplastic exposure route — when you think about it, it makes sense, you’re letting plastic sit on your skin all day!
It’s true — a lot of natural fiber clothing can be expensive. Thrift apps like Depop , ThredUp , or Poshmark to source natural fiber clothes at great prices.
Use glass or stainless steel containers Store food in non-plastic containers to avoid potential leaching of plastic chemicals into what you eat, and never microwave food in plastic containers or bags.
Glass, stainless steel, and ceramic containers are all great alternatives to plastic.
Vacuum and dust regularly This can help remove microplastic particles that settle in your home, and prevent you from inadvertently inhaling them. A robotic vacuum can help you put the process on autopilot.
Choose natural cosmetics and personal care products Personal care products are a common route for microplastics exposure outside of the food we eat and drink.
Because women tend to use more personal care products than men, Million Marker founder Jenna Hua told TIME that women tend to have much higher levels of plastic chemicals in their blood for this reason. “If you test women, they tend to have a very high exposure because they use so many products,” Hua says. According to recent research, about 87% of products from major cosmetics brands contain microplastics !
Opt for cosmetics and personal care products with natural ingredients and minimal packaging. You can scan personal care products with the app Beat The Microbead to understand how much plastic pollution might be inside any given personal care product.
Air purification Consider using an air purifier with a HEPA filter to remove airborne microplastics. An air filter with a HEPA filter can remove 99.7% of the smallest particles in the air.
You can find guides to the best air filters at
Both guides align around similar choices and include both stand-alone options and choices you can install to your HVAC system to protect your entire home.
Microplastics present a significant challenge to society While more research is needed to fully understand the long-term consequences of chronic microplastic exposure, the current evidence suggests that it may have substantial negative effects on digestive and overall health.
Addressing this issue requires a multifaceted approach. On a societal level, reducing plastic use and improving waste management are key strategies to mitigate exposure. On an individual level, being mindful of plastic use, choosing products with less plastic packaging, and using filtration systems for drinking water can help reduce personal exposure.
As we continue to uncover the full extent of microplastic pollution and its health impacts, it is clear that urgent action is needed. By raising awareness, supporting research, and implementing effective mitigation strategies, we can work towards a future where the threat of microplastics to our health and environment is significantly reduced.
