Plastic inside us: How microplastics could reshape our bodies and minds | Plastic
MMicroplastics are found almost everywhere: in the blood, placenta, lungs, and even the human brain. One study estimated that our brain organs alone may contain 5 grams of the substance, or roughly a teaspoon. If this is true, then plastic isn’t just wrapped around our food or woven into our clothes, it’s lodged deep within us.
Now, researchers suspect that these particles may also interfere with the gut microbiome. When Dr. Christian Bacher Deutsch, of the University of Graz in Austria, exposed gut bacteria from five healthy volunteers to five common microplastic particles, the bacterial populations transformed — along with the chemicals they produce. Some of these changes reflect patterns associated with depression and colorectal cancer.
“Although it is too early to make specific health claims, the microbiome plays a central role in many aspects of well-being, from digestion to mental health,” says Butcher-Deutsch, who presented his work at the recent European United Congress of Gastroenterology in Berlin. “Therefore reducing exposure to microplastics where possible is a wise and important precaution.”
Such discoveries raise troubling questions: How much plastic do we each carry, does it really matter, and can we do anything about it?
Microplastics are eliminated from packaging, clothing, paints and cosmetics. Car tires And other items. Some are small enough to seep through the linings of our lungs and guts into our blood and internal organs, and even into our cells. What happens next is still largely unknown.
“Designing a definitive experiment is difficult, because we are constantly exposed to these particles,” he says. Dr. Jaime Rossa neuroscientist at the University of Rhode Island in the United States. “But we know that microplastics are present in almost every tissue examined, and recent studies suggest that we are now accumulating much more plastic than we were 20 years ago.”
Ross’s curiosity about plastics began when she was a teenager, watching her mother’s spaghetti sauce containers corrode. “A lot of us assumed that plastic was inert, that it wouldn’t shed or react, but I realized that wasn’t the case,” she says.
Fast forward several decades, and I began studying what microplastics might do to the mammalian brain. Her first Study published in 2023She offered a hint: Mice drinking water laced with microplastics began to behave differently.
Normally, if mice are placed in a brightly lit box, they will hug the walls defensively. But those exposed to plastics relentlessly ventured out into the open, behavior often seen with aging and neurological diseases.
When the mice were dissected, plastic was found in every organ, including the brain, where a key protein associated with brain health, GFAP, had been depleted, mirroring the pattern seen in depression and dementia.
Since then, human studies have increased concern. Microplastic particles have been discovered in the brains of dementia patients, and in arterial plaques in people with heart disease. Those with plastic-laden plaques were almost five times more likely to have a stroke, heart attack or die within three years.
Results like these made me stop. Like Ross, I had long assumed plastics were harmless, and didn’t think much about chewing on the tips of fountain pens, wearing synthetic clothing and reheating leftovers in takeaway containers. So when I heard about a £144 test from… Plastic toxins Promising to reveal how many microplastics were circulating in my blood, I pricked my finger and sent a drop.
Alan Morrison, CEO Arrow Lab SolutionsThe US company behind the test said its goal is to provide people with an estimate of their exposure to microplastics, allowing them to make lifestyle changes if they wish. “Sometimes that test is the knockout punch they need to get some of that [plastic] “Get things out of their home and limit their exposure,” he says.
My test detected four microscopic particles – the equivalent of about 40 per milliliter of blood. The lab said that based on their size, one of them likely got there through my intestines while the other three were likely inhaled. Although that puts me in the bottom quarter of the 4,000 tests done so far, “it still represents about 200,000 plastic particles in my bloodstream,” Morrison says. “But considering the average person has over a million, you’re in relatively good shape.”
However, as other experts point out, no one really knows what a “safe” level of microplastic looks like. The field of research is still young, he says, and consumer testing is “very premature.” Professor Stephanie Wrighta microplastics researcher at Imperial College London: “The test results say you have 40 particles per ml of blood – but we don’t know if that’s bad or good, what type of plastic it is, where they come from, what they do or where they go.”
Scientific studies have used a variety of methods, making comparison between them difficult. Some techniques — including those used to measure the amount of microplastics in human studies on dementia and heart disease — can suffer from interference from biological tissue. For this reason, their results are far from conclusive, and should “be taken with a pinch of salt,” Wright says.
Even if it were possible to accurately quantify the amount of particles found in blood or other tissues, it is uncertain whether all microplastics pose the same level of risk.
“Plastic is very heterogeneous. There are different types, but they also have different shapes, which may influence their harmful effects,” he says. Dr. Wahida Abdel Salam At Queen Mary University of London. The size of the particles is also important. The smaller they are, the more likely they are to cross biological barriers into organs or cells.
There are other challenges before we know for sure whether microplastics are harming us: rodent studies may not translate to humans; Because they are much smaller, plastic particles of the same size may be ingested and processed very differently, Salam says.
So where does that leave us? We’re constantly exposed to these particles, and “Historically, we know that exposure to too many particles is bad,” Wright says, pointing to air pollution as an example. “We just have to understand if there is anything about these particles that makes them disproportionately harmful.”
Another pressing question is whether some subjects are more at risk than others. Modern Follow-up study Ross suggested that mice carrying the APOE4 gene associated with Alzheimer’s disease experienced more severe cognitive decline in response to exposure to microplastics than those with less severe genes.
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Despite these gaps, many researchers are quietly changing their habits. “Minimizing exposure is likely to have an overall benefit,” Wright says.
If there’s a silver lining, it’s that although research suggests levels of microplastics in our bodies have risen sharply in recent years, older people don’t seem to contain more than younger people. “I found that positive, because it tells me we might be able to get it out of our bodies,” Ross says. Identifying ways to speed up this natural process, if it exists, is likely to be a major research focus in the coming years.
As for me, I cannot get rid of those particles that number more than 200 thousand. Whether that number is accurate or not, it’s hard not to look around my plastic-covered life and wonder how I could possibly begin to unpack it. Reheating leftovers in glass instead of plastic is a good place to start. And I will definitely stop chewing on pens.
How to reduce your exposure
Although it’s impossible to completely avoid microplastics, scientists say there are practical ways to reduce your personal exposure.
Start in the kitchen. “The thing you definitely want to avoid is heat with plastic,” Ross says. “So do not cook your food with plastic utensils, and do not put hot drinks or food in plastic.”
Salam says she has stopped cooking food in the microwave in plastic containers: “When you expose plastic polymers to heat or direct sunlight, this is what turns them or breaks down into microplastic particles.”
Ross suggests examining daily rituals like making a cup of tea or chopping an onion: “Tea bags can release a lot of nano and microplastics. Even if the tea bag is paper, it can be sealed with plastic glue, so maybe you could try loose leaf tea. Do you cut up a plastic sheet? Because that can contaminate the food as well.”
Opt for glass or stainless steel bowls, utensils and coffee utensils and use wooden cutting boards instead.
Although tap water contains some microplastics, tap water in the UK is treated to remove almost all of them, and studies suggest that many brands of bottled water contain much more.
Beyond the kitchen, Ross recommends thinking about bedding and personal care products. “Try to get more natural fibers, especially for the things you sleep in — bed sheets, blankets, pillows, because you can inhale nano- and microplastics,” she says.
Check the labels on personal care products and cosmetics: Although microplastic beads in, for example, face wash are now banned, some cosmetics and materials such as lotions, lipsticks and eye shadows may still contain nanomaterials or microplastics under names such as polyethylene, polypropylene, polyurethane or acrylates. Also look for hidden plastic in menstrual products, and choose those made with 100% cotton or silicone cups.
Airborne plastics are another concern. Although indoor environments generally have higher levels due to synthetic textiles and upholstery, “tire wear from high-traffic environments is another source of exposure to microplastics,” says Wright. “In the same way you avoid air pollution by walking on quiet streets, trying not to drive next to traffic and closing your car windows. This would theoretically reduce exposure to microplastics.”
Finally, think about your environmental footprint. Plastics thrown into a landfill will decompose slowly, resulting in more microplastics being eliminated. “If you have any plastic items in your home, such as plastic containers, reuse them to store sewing materials and other non-food items,” Ross says. “If you put it in recycling, it may not get recycled and you’re just adding to the broader problem.”