The inflammation problem
A potentially larger health issue emerges from our bodies yet again doing what they are supposed to do when encountering microplastics. Particles can trigger an immune response when they enter your bloodstream, explains Nienke Vrisekoop, PhD, assistant professor at UMC Utrecht.
White blood cells have no issue breaking down things like bacteria, but microplastics cannot be degraded. When a white blood cell engulfs a certain mass of microplastics – either many small particles or a singular large one – it dies, releasing its enzymes and causing local inflammation.
Meanwhile, the plastic particle remains. So more white blood cells attack.
“This triggers continual activation that can result in various adverse effects, including oxidative stress and the release of cytokines that trigger inflammatory reactions, said Dr. Vethaak.
And “chronic inflammation is the prelude to chronic diseases,” said Dr. Leslie. “Every chronic disease, like cancer, heart disease, and even neuropsychiatric diseases like Parkinson’s or major depression, begins with inflammation.”
Meanwhile, inhaling microplastic particles can lead to respiratory diseases and cancer.
“The smallest particles – less than one-tenth of a micrometer – penetrate deep into the lungs and even into the bloodstream, causing damage to the heart, blood vessels and brain,” said Dr. Vetaak. “The only direct evidence comes from workers in the textile and plastic industries that had been exposed to very high amounts of plastic fibrous dust.”
Microplastics as carriers
Microplastics can also pick up harmful substances and deliver them into your body.
“When they’re in an environment, they basically can suck up [chemicals] like a sponge,” said Dr. Dusza. “These chemicals are known environmental pollutants, like pesticides, fluorinated compounds, flame retardants, and so on.”
Once in the body, these chemicals can be released, potentially leading to cancer, chronic inflammation, or other unknown effects.
Particles can also act as a vector for microbes, bacteria, and viruses. A September 2022 study found that infectious viruses can survive for 3 days in fresh water by “hitchhiking” on microplastics. Their porous nature provides microbes with a perfect environment in which to live and reproduce, said Dr. Dusza. If you ingest the plastics, you ingest the microbes.
How to minimize exposure
There is no way to avoid microplastics. They’re in the air we breathe, the products we use, the water we drink, and the food we eat.
Dr. Danopoulos reviewed 72 studies to quantify our consumption of microplastics in drinking water, salt, and seafood.
“We are exposed to millions of microplastics every year, and I was only looking at three food sources, so there are really a lot more,” he said. “Once plastic waste is mismanaged and it enters the environment, there is very little we can do to extract it.”
That said, we can take steps to lower our exposure and keep the problem from getting worse.
Water filtration is one option, though it is not perfect. Research has shown that municipal water treatment can be effective. An October 2021 study found that two methods – electrocoagulation-electroflotation and membrane filtration – can be 100% effective in removing microplastics from treated water. The problem? Not all municipal water treatment uses these methods – and you would have to investigate to find out if your locality does.
As for at-home filtration methods, they can be effective but can also be dicey. Some consumer brands claim they remove microplastics, but how well depends on not just the type of filter but the size of the particles in the water. Meanwhile, how do you know if a filter is working on your water without testing it, something few people will do? Best not to take a brand’s claims on face-value, but look for independent testing on at-home brands.
A longer-term project: Reduce our risk by reusing and recycling plastic waste. Limiting our consumption of plastic, especially single use plastic, decreases the amount available to become micro- and nanoplastics.
We must all learn to not treat plastic as waste, but rather as a renewable material, said Dr. Cassee. But if that seems like a tall order, it’s because it is.
“You’re a human being and you have a voice and there are a lot of other humans out there with voices,” said Dr. Leslie.
“You sign a petition in your community. You talk about it with your friends at the pub. If you’re a teacher, you discuss it in your class. You call your elected representatives and tell them what you think and how you want them to vote on bills.”
When people start working together, you can really amplify that voice, said Dr. Leslie.