Study claims to have found plastics in people’s stool
Experts have warned a study claiming to have identified microplastics in people’s stool is too small and premature to draw any credible conclusion.
Scientists in Austria say they have detected tiny bits of plastic in people’s stool for the first time.
Presenting their findings at a congress in Vienna, researchers from the Medical University of Vienna and the Environment Agency Austria said their pilot study detected so-called microplastics in all samples taken from eight volunteers in Europe, Russia and Japan.
But experts have warned the study is too small and premature to draw any credible conclusion.
Microplastics — defined as pieces smaller than 5 millimetres – have previously been found in water, animals and food, but so far studies have not proved they pose a risk to human health.
Still, there is growing public concern about their apparent ubiquitous presence in the environment, and the head of Germany’s Green party said the Austrian study was “a further alarm signal”.
It's small scale and not at all representative Martin Wagner, Norwegian University of Science and Technology
Robert Habeck told the Funke media group that microplastics should be banned from cosmetic products and the use of plastic packaging should be greatly reduced.
However, experts say it is not surprising that microplastics would be found in human samples too, and said the Austrian study raises many questions.
“It’s small scale and not at all representative,” said Martin Wagner, a biologist at the Norwegian University of Science and Technology.
He noted that the study was not reviewed by independent scientists and the authors have not provided details about the measures taken to prevent samples from becoming contaminated.
“In the worst case, all the plastic they found is from the lab,” Mr Wagner told The Associated Press.
Even if microplastics are found in stool, this does not mean they have entered the human body, he said.
Unlike other substances we eat, microplastics are too large to be absorbed by cells in the gut and simply pass through.
His concerns were echoed by Mark Browne, an expert on microplastics at the University of New South Wales, Australia, who said the study lacked crucial details.
“Poor quality observations of contamination do not represent well the scientific method and therefore in my humble opinion do not help us understand impacts on humans or manage them,” Browne said.
The Austrian authors acknowledged that “further studies are necessary to assess the potential risk of microplastic for humans”.
They plan to submit a detailed study for independent review in the coming months.