New research suggests that humans all over the world are eating and drinking tiny particles of plastics. Here's what that might mean for our health.

By Amanda MacMillan
October 23, 2018

Scientists have been warning us for years about the potential dangers of plastics in the human food chain. Now, they say they have the first real evidence that we really are taking in—and putting out—microscopic particles of the petroleum-based stuff. That’s right, people: According to a new study, we’ve got plastics in our poop.

The new research was presented in Vienna this week at UEG Week, a conference for the United European Gastroenterology organization. It involves stool samples taken from eight participants around the world: in Finland, Italy, Japan, the Netherlands, Poland, Russia, the United Kingdom, and Austria.

At the conference, researchers from the Medical University of Vienna and the Environment Agency Austria reported that every single stool sample in their analysis tested positive for the presence of microplastics—defined as particles of plastic smaller than 5 millimeters. Up to nine different types of plastic were identified in the samples, including common household and food-industry staples like polypropylene, polyethylene, and terephthalate.

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Sure, it’s kind of gross to know that we’re consuming plastic. But what exactly does that mean for our health? That part is still unclear, exactly—but according to a UEG Week press release, microplastic may accumulate in the gastrointestinal tract, “where it could affect the tolerance and immune response of the gut.” It may also help transmit toxic chemicals and pathogens into the body, scientists say.

How those plastic particles get into the GI tract also isn’t known for sure. But the researchers behind the study say that plastic food and drink containers may have something to do with it.

Microplastics are sometimes manufactured for specific purposes (like the tiny exfoliating beads in some skin-care products), but they can also be created unintentionally when larger pieces of plastic break down due to weathering or wear and tear. Previous research has shown that bottled water can contain microplastics, and that people who frequently eat at restaurants are more likely to have higher levels of phthalates—a chemical in some plastics—in their urine than those who mostly eat at home.

We could also be consuming animals—like fish and other types of seafood—that have ingested microplastics found in the environment. The participants in the new study kept food diaries in the week leading up to their stool samples, which showed that they were all exposed to plastic-wrapped foods or plastic bottles. None were vegetarians, and six had consumed fish.

In the new study, all of the microplastics found were between 50 and 500 micrometers. On average, every 10 grams of stool contained about 50 microplastic particles.

RELATED: What the Recycling Symbol on a Plastic Container Can Tell You About Its Potential Dangers

Lead researcher Philipp Schwabl, MD, said in a press release that this study confirms what has long been suspected: that plastics can reach the human gut. This is concerning for human health, he says, especially for patients with gastrointestinal diseases.

“While the highest plastic concentrations in animal studies have been found in the gut, the smallest microplastic particles are capable of entering the blood stream, lymphatic system and may even reach the liver,” Dr. Schwabl said. “Now that we have first evidence for microplastics inside humans, we need further research to understand what this means for human health.”

That research can’t come soon enough, many scientists and activists say. Global plastic production has increased drastically from the 1950s, according to the World Economic Forum, and continues to grow every year. Not only are most people regularly exposed to plastic as part of their everyday lives, but an estimated 2 to 5% of plastics produced end up in waterways, where they are consumed by sea animals and enter the food chain.

RELATED: Chemicals in Food Wrappers May Hurt Your Health—and Your Waistline

In July, the American Academy of Pediatrics (AAP) issued a statement aimed at helping people navigate the confusing world of plastics and potential health risks. The organization recommends avoiding plastics that contain the recycling codes 3, 6, and 7, unless they are also labeled as “biobased” or “greenware.”

These classes of plastics (which can include phthalates, styrene, and bisphenols) are associated with the strongest evidence of potential health risks, says the AAP, especially for children and pregnant women. But the statement also recommends taking common-sense precautions when dealing with all kinds of plastic: Don’t put them in the microwave or dishwasher, it says, and try to choose whole foods over processed and packaged ones whenever possible.

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