05/11/2025
Such great information and a good reminder for all of us. As a former flight attendant, it especially makes me think of air crew - who use plastic bottles every day. It’s not really possible to avoid plastics completely anymore, but reducing them where possible is worth it and really does make a difference. 💚🌏
Two recent online articles have highlighted the need for a greater awareness of the potential health benefits of reducing micro- and nanoplastic exposure. The emergence of microplastics (1 µm to 5 mm) and nanoplastics (less than 1 µm) has raised alarms about their harmful effects on human health. Nanoplastics are especially hazardous due to their smaller size and enhanced ability to infiltrate the human body.
The first article reviews a recent paper by Sarah Sajedi and colleagues, published in the Journal of Hazardous Materials, which examines the science around the health risks posed by single-use plastic water bottles. They are serious, she says, and seriously understudied.
In her analysis of more than 140 scientific papers, Sajedi reports that people ingest an estimated 39,000 to 52,000 microplastic particles each year. For those who rely on bottled water, that number climbs even higher, about 90,000 additional particles compared to people who primarily drink tap water.
According to Sajedi, the health risks are significant. Once inside the body, these small plastics can pass through biological barriers, enter the bloodstream and reach major organs. Their presence may contribute to chronic inflammation, cellular oxidative stress, hormone disruption, reproductive issues, neurological damage, and some cancers. Still, their long-term impacts are not fully understood, largely because of limited testing and the absence of standardised ways to measure and track them.
Sajedi says: “Drinking water from plastic bottles is fine in an emergency but it is not something that should be used in daily life. People need to understand that the issue is not acute toxicity—it is chronic toxicity.”
The second article in MedPage Today highlights the ubiquitous and insidious nature of micro- and nanoplastics. One of the authors (Meyer) is an emergency physician who believes it is now time to be warning patients about reducing exposure.
Teasing out the health impacts of micro- and nanoplastics requires some nuance. There is never going to be a randomised controlled trial: it is hard to conceive of a control group with no plastics exposure (given their ubiquity) and unethical to deliberately expose an experimental group to high-dose plastics. But waiting for perfect data risks ignoring an escalating health threat. Hence, much of what we know is by necessity extrapolated from animal studies and observational trials -- and there are multiple red flags.
In humans, studies are slowly emerging. In 2024, researchers followed patients undergoing carotid endarterectomy and found that those with microplastics in their plaque had a significantly higher rate of myocardial infarction, stroke or death 34 months later. More recently, decedent human brains from 2016 and 2024 were evaluated for microplastics: concentrations were significantly higher among individuals diagnosed with dementia compared to those without dementia (and plastic concentrations increased 50% from 2016 brains to 2024 brains, consistent with increasing environmental exposure). Last year, researchers at University of California San Francisco (UCSF) reviewed existing human and animal studies and found a suggestion of harm to reproductive, digestive and respiratory health in humans, as well as a possible link with colon and lung cancer.
All of this has been enough to convince Meyer that it is now time to start warning patients about microplastics. Although it would be impossible to avoid plastics altogether, there are some practical steps people can take to decrease their exposure.
To start (as per the first article), it makes sense to give up single-use plastic water bottles in favour of reusable steel or glass bottles. The water in plastic bottles has been found to contain 20 times more microplastics than tap water.
It is also a good idea to limit plastic in the kitchen, since we acquire many of our microplastics by eating and drinking them. This means using wooden cooking utensils and cutting boards over plastic ones, foil over plastic wrap, and glass food storage over plastic. If possible, avoid nonstick and plastic cookware. In situations where plastic containers are unavoidable, don't microwave food in them. And wash them by hand instead of the dishwasher, since heating plastic hastens its breakdown and chemical leaching.
At the supermarket, pack groceries in reusable cloth or paper bags, and try to avoid fruits and vegetables wrapped or packaged in plastic (admittedly challenging). And finally, limit ultraprocessed foods. Not only are they associated with increased mortality, obesity, chronic disease and malignancy, but they also come coated in plastic.
Could the demise of modern civilisation be caused by something we cannot even see?
For more information see: https://scitechdaily.com/scientists-warn-bottled-water-may-pose-serious-long-term-health-risks/
and
https://bit.ly/47TCyO3
