Small plastic pieces known as microplastics were found in stool samples of every participant in a small pilot study presented this week at a prestigious global gastroenterology conference.

Researchers from the Environment Agency Austria and the Medical University of Vienna followed eight healthy volunteers from different parts of the world (Finland, Italy, Japan, the Netherlands, Poland, Russia, United Kingdom and Austria). The participants kept a diary of the food and drink they consumed for a week. Then, researchers tested their stool for 10 different types of plastics.

Nine different types of plastics were found in the samples, according to the study. An average of 20 microplastic particles measuring between 50 and 500 micrometers were found per 10 grams of stool.

Philipp Schwabl, lead researcher, said this is the first study of its kind and he's now seeking funding for further research.

"Personally, I did not expect that each sample would be tested positive," Schwabl said.

He's unsure of exactly how the plastics got into the bodies of his participants, but did say most participants drank liquids from plastic bottles and also ate seafood, who could be bringing microplastics from ocean pollution up the food chain. No vegetarians or vegans were involved in the study.

The study was largely limited by its small sample size, and Schwabl said additional studies must be conducted to better understand how diet and lifestyle can contribute to microplastic ingestion. Schwabl is presenting the research at the 26th annual United European Gastroenterology conference in Vienna, Austria.

Several unrelated studies have suggested microplastics could be finding their way inside human guts.

“Recent studies have found plastics in seafood, wildlife, tap water, and now in salt. It’s clear that there is no escape from this plastics crisis, especially as it continues to leak into our waterways and oceans,” said Mikyoung Kim, campaigner at Greenpeace East Asia in a statement, following a study published earlier this month revealing 90 percent of the sea salt sold globally contain microplastics.

Another study published earlier this year examining 259 water bottles from brands sold across nine countries found that 93 percent were contaminated with microplastics. Even some tap water has tested positive for tiny plastic particles.

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