Microplastics detected in human feces internationally, study finds

There's plastic in the poop.

A team of scientists say they have found tiny plastic particles in human stools from a global sampling — and every sample tested positive.

"This is the first study of its kind, and confirms what we have long suspected, that plastics ultimately reach the human gut," said lead researcher Philipp Schwabl, a physician scientist at the Medical University of Vienna.

The small study, conducted by the University of Vienna with Environment Agency Austria, was presented Monday at the annual United European Gastroenterology conference.

"Of particular concern is what this means to us, and especially patients with gastrointestinal diseases," Schwabl said. "While the highest plastic concentrations in animal studies have been found in the gut, the smallest microplastic particles are capable of entering the bloodstream, lymphatic system, and may even reach the liver. Now that we have first evidence for microplastics inside humans, we need further research to understand what this means for human health."

To conduct the study, researchers monitored the stools of a group of eight participants from Finland, Italy, Japan, the Netherlands, Poland, Russia, the United Kingdom, and Austria. They detected particles of polypropylene (PP), polyethylene-terephthalate (PET), and others.  In all, nine types of plastic were found in the stool samples. The researchers found an average of 20 microplastic particles per 10 grams of stool.

Though the study was limited, the research suggests plastics could be widespread throughout the human food chain.

Microplastics are defined as tiny particles, less than 5mm (13/64 of an inch). The particles come from a variety of products, as well as from plastics that break down in the environment and find their way into waterways.  Up to nine different plastics, sized between 50 and 500 micrometres, were found in the stool.

The scientists said microplastics may impact human health, starting in the gastrointestinal tract, and could affect the immune response in the gut, either through an accumulation of the plastics or by transmitting toxins contained in them.

The researchers could not identify precisely where the plastics came from. Each study participant kept a food diary in the week leading up to his or her stool sampling. The diaries showed the participants were exposed to plastics in various ways: by eating food that had been wrapped in plastic or by drinking from plastic bottles. None were vegetarians. Six had eaten fish.

"This study is brilliant and ingenious," chemist and microplastics expert Shari Mason of the State University of New York at Fredonia told NPR. Mason was not involved in the study, but she said the scientists confirmed "what so many of us suspected — we're ingesting these plastics."

Plastics are increasingly viewed as a global problem. The researchers said that plastics production is growing each year, and that 2 percent to 5 percent of all plastics produced end up in the oceans, where they are eaten by sea animals with potential to enter the human food chain. Microplastics have been detected in tuna, lobster, and shrimp.

Earlier this year, a team of scientists working with Orb, a nonprofit journalism organization, found that a single bottle of water can contain dozens — or even thousands — of tiny plastic particles.  Tests on more than 250 bottles showed almost all had contamination from microplastic particles that included PP, PET and nylon. A few bottles showed no presence of plastics. In all, scientists working with the publication found plastic in 93 percent of the samples.