A shocking discovery: The stark difference between Korean and American drinking-water culture and the truth about the plastic inside our bodies.
Microplastics are tiny particles of plastic, typically less than 5 millimeters in size, that have become a growing concern for both human health and environmental pollution. These plastic fragments are so small that they can easily enter the human body through everyday activities, whether we are drinking water, eating food, or simply breathing air.
The World Health Organization has highlighted the potential health effects of microplastics, noting that human exposure is now widespread due to their presence in various environmental media. While the full extent of their adverse health effects is still being studied, the fact that these tiny particles are found in our drinking water and food supply underscores the urgent need for further research. As microplastics continue to accumulate in the environment, understanding their impact on the human body is more important than ever.
An Unfamiliar Scene I Saw on the Streets of the United States: BYOB Culture
A recent testimony from a traveler who returned from the United States has been heating up online communities:
“In Korea, disposable plastic water bottles are something we take for granted. But while walking around in the U.S., I noticed that everyone was carrying stainless-steel tumblers or glass bottles. At cafés, at schools, at workplaces everywhere. At first I thought, ‘They must be very environmentally conscious,’ but later I realized this wasn’t just about protecting the environment.”
In fact, in many cities across the U.S. and Europe, the culture of “Bring Your Own Bottle (BYOB)”, meaning carrying your own water bottle, is already deeply established.
Major franchises like Starbucks and Dunkin’ offer discounts to customers who bring their own tumblers, and universities and corporations install free water stations throughout buildings to reduce the use of disposable plastics.
So where does Korea stand right now?
Korea’s Reality: One of the Highest Plastic-Consuming Countries in the OECD
Korea remains a top consumer of disposable plastics, especially bottled water.
| Indicator | Figures |
| Per-capita plastic usage among OECD countries | 3rd place ( as of 2022) |
| Annual per-capita bottled-water consumption | Approximately 96L |
| Single-use plastic cup consumption | Approximately 25.7billion per year |
The bottled-water market is also growing rapidly.
In recent years, Korea’s bottled-water market has steadily expanded and has now exceeded the 1-trillion-won range.
Because it is “convenient” and “looks clean,” we choose water in plastic bottles far more often than we realize.
But an important question arises here: “Are plastic water bottles really safe, or do they pose hidden health risks?”
How Microplastics Enter Our Bodies
Microplastics in human body can enter through multiple sources:
- Bottled water and beverages
- Food packaging and single-use plastics
- Airborne microplastics from the environment
- Household plastic containers
- Contaminated food and beverages
- Exposure through dermal exposure, such as contact with contaminated media and personal care products
Uncomfortable Truth Science Tells Us: Effects of Microplastics on Human Health Are Already a Reality
1. Microplastics Found in the Placenta
In 2021, the Ragusa research team analyzed the placentas of six healthy pregnant women.
The results were shocking:
- Microplastic particles were detected in every placenta, with microplastics detected in human tissues, highlighting their ability to accumulate in the body.
- They were found in nearly all regions of the maternal side, the fetal side, and the chorionic membranes.
This indicates that plastic particles to which the mother is routinely exposed may cross the placental barrier and reach the fetal environment. Concerns that the health effects of microplastics could extend to the next generation are no longer theoretical; they are becoming a reality.
2. Plastic Is Also Detected in Adult Blood
In 2022, a Dutch research team led by Leslie³ examined the blood of 22 healthy adults. The results:
- Microplastics were detected in 17 out of 22 people (77%)
- Major detected components: PET (polyethylene terephthalate), polystyrene, polyethylene
In other words, we are not merely living alongside disposable plastics.
There is a high likelihood that fragments of these plastics have already entered our bodies and are circulating within us.
Microplastics have been detected in various human tissues, including blood, placenta, and even organs such as the lungs and breast milk, raising concerns about their widespread presence and potential health risks.
3. The Blood–Brain Barrier Is Not a Perfect Shield
For a long time, it was believed that “the brain is relatively safe because the blood–brain barrier (BBB) protects it.”
However, recent studies have detected micro- and nanoplastics in brain tissue as well.⁴
According to research published in 2023, nanoplastics can cross the blood–brain barrier and accumulate in brain tissue, and this may be linked to neuroinflammation and cognitive decline.
This suggests that the health effects of microplastics may extend all the way into the central nervous system, a development that requires even greater caution.
Detection and Analysis: How Do We Find Microplastics in the Human Body?
Detecting microplastics in the human body is a challenging and evolving area of environmental research. Scientists use advanced techniques such as microscopy, spectroscopy, and chromatography to identify and measure microplastics in human tissues and fluids. These methods allow researchers to distinguish plastic particles from other materials, even when they are present in extremely small quantities.
Recent studies have successfully detected microplastics in human tissues, including blood and breast milk, highlighting the extent of human exposure. However, the process is not straightforward; microplastics can be difficult to isolate and analyze due to their tiny size and the complexity of biological samples. As a result, further research is needed to improve detection methods and to better understand the health risks associated with microplastics in the human body.
The environmental research community is actively working to develop more accurate and reliable techniques for monitoring microplastics in human samples. By advancing our ability to detect these particles, scientists hope to gain deeper insights into their distribution, potential adverse effects, and ways to reduce exposure, ultimately protecting both human health and the environment.
Microplastics in Food and Beverages
Microplastics are not limited to bottled water. They are also present in contaminated food, packaged foods, seafood, and other beverages.
Contaminated food and beverages are primary sources of ingesting microplastics, which can lead to adverse health effects due to chemical leaching from plastics.
Microplastics accumulate through the food chain, especially in seafood, increasing the risk of human exposure. This increases microplastics ingestion and contributes to the health effects of microplastics in humans over time.
The Effects of Long-Term Exposure on Our Metabolic System
What happens when plastic particles enter the human body?
Microplastics can interact directly with human cells, causing cellular damage, inflammation, and even neurotoxicity, as shown in laboratory studies. Inhaled microplastics can also cause oxidative stress in the airways and lungs, leading to respiratory symptoms such as coughing and shortness of breath.
Animal studies offer indirect but important clues about the potential risks.
In a 2023 animal study by Deng et al., rodents exposed to microplastics over a long period showed the following changes:⁵
1. Liver Dysfunction
Patterns resembling metabolic fatty liver were observed, with inflammation and fat accumulation occurring simultaneously.
2. Increased Insulin Resistance
Long-term microplastic exposure was connected to impaired glucose metabolism and an increased risk of metabolic disease.
3. Disruption of Gut Microbiota
Other studies⁶ indicate that microplastics can alter the composition of gut microbes in the gastrointestinal tract and digestive system, triggering systemic inflammatory responses. Of course, there are limitations in applying animal study results directly to humans. But one thing is clear: we are well past the stage where we can say ‘there is no impact.’
These studies also show that microplastics can induce an inflammatory response and toxic effects in various organs, especially with chronic exposure, leading to cumulative impacts such as metabolic disorders and other health complications.
Then what should we change?
A Three-Step Guide You Can Start Practicing Right Now
Step 1: Break Away from Disposable Plastic Water Bottles
Practical Tip: Put “my water bottle” in your work bag as a default item. This naturally reduces how often you buy bottled water from convenience stores.
- Use stainless-steel or glass bottles
- Choose BPA-free certified products
- Use water from a purifier or boiled water
Step 2: Reduce the ‘Invisible Plastic Exposure’ Inside the Home
Practical Tip: Instead of putting plastic containers directly into the microwave, transfer food to glass storage containers or ceramic bowls before heating.
- Minimize plastic leaching caused by heat
- Avoid prolonged contact between food and plastic packaging
- Use stainless-steel or ceramic cups for hot beverages
- Use air purifiers and ensure proper ventilation to reduce inhalation exposure to airborne microplastics
- In occupational or high-exposure environments, consider respiratory protection such as masks or air filtration to reduce respiratory inhalation risks.
Step 3: Strengthen the Body’s ‘Internal Defense System’ from a Chronic-Disease Perspective
Practical Tip: It is crucial to boost the body’s natural defenses against external toxins.
- Restore gut microbial balance: probiotics, dietary fiber
- Enhance mitochondrial function: antioxidant nutrients, regular exercise
- Improve blood flow and reduce oxidative stress: proper hydration, stress management
- Rebalance the autonomic nervous system: adequate sleep, meditation, photobiomodulation (PBM) therapy
Small Changes That Make a Big Difference
As scientific evidence on the health effects of microplastics continues to accumulate, plastic use is no longer just an environmental issue; it is becoming a personal health issue. Microplastics have been linked to a range of health issues, including inflammation, metabolic disorders, and organ toxicity. Findings suggest that ongoing research will continue to reveal new implications of microplastic exposure for human health.
Of course, completely avoiding plastic in modern society is nearly impossible. However, even the small habit of reducing the use of a single disposable plastic water bottle can, over time, meaningfully reduce the amount of microplastics that accumulate in our bodies. How about carrying your own water bottle starting today? It’s the smartest choice that protects both the environment and your own health.
Conclusion and Future Directions
In conclusion, the potential impact of microplastics on human health is a growing concern that demands ongoing research and global attention. With global plastic production and plastic waste continuing to rise, it is essential to improve waste management practices to reduce the release of microplastics into the environment. Understanding the cellular and molecular mechanisms by which microplastics affect the human body will be key to developing effective strategies for mitigating health risks.
Future research should focus on the effects of microplastics on human health, including their potential role in chronic diseases, and on finding ways to reduce human exposure through better product design and sustainable plastic use. International organizations such as the United Nations Environment Programme (UNEP) play a crucial role in supporting research and policy initiatives that address both the environmental and health impacts of microplastics. By working together, we can reduce the risks associated with microplastics and create a healthier, more sustainable future for all.
Start protecting your health today! Switch to a reusable water bottle, reduce plastic use at home, and learn more about the health effects of microplastics. Small daily habits can make a lifelong difference.
References
- OECD (2022). Plastic waste generated per person. OECD Environment Statistics (Waste streams).
- Ragusa, A., Svelato, A., Santacroce, C., et al. (2021). Plasticenta: First evidence of microplastics in human placenta. Environment International, 146, 106274.
- Leslie, H. A., van Velzen, M. J. M., Brandsma, S. H., et al. (2022). Discovery and quantification of plastic particle pollution in human blood. Environment International, 163, 107199.
- Kopatz, V., Wen, K., Kovács, T., et al. (2023). Micro- and nanoplastics breach the blood–brain barrier (BBB): Biomolecular corona’s role revealed. Nanomaterials, 13(8), 1404.
- Deng, Y., Yan, Z., Shen, R., et al. (2020). Microplastics release phthalate esters and cause aggravated adverse effects in the mouse gut. Environment International, 143, 105916.
- Lu, L., Wan, Z., Luo, T., et al. (2018). Polystyrene microplastics induce gut microbiota dysbiosis and hepatic lipid metabolism disorder in mice. Science of The Total Environment, 631-632, 449-458.
