The dangers of microplastics have been called into question

Scientists have questioned most of the high-profile studies that have found microplastics in the human body. Now the scientific community is rethinking the potential health damage microplastics allegedly pose, The Guardian reports .

The main problem is that, as the publication notes, some studies are published in a hurry, omitting routine scientific checks. Because of this, for example, works that stated that micro- and nanoplastics were found in the brain , testicles, placenta, arteries and other places were called into question.

At least 18 high-profile studies on microplastics have already been challenged by the scientific community. This is because their authors did not take into account that some tissues of the human body can affect measurements in the same way as ordinary plastic. The voiced doubts produced the effect of a bomb exploding, writes The Guardian

“It really forces us to reconsider everything we think we know about microplastics in the body. Which, as it turns out, is actually not that much. Some researchers make extraordinary claims without providing even ordinary evidence,” chemist Roger Kuhlman told the publication.

A key way to measure the mass of microplastics in the body was to evaporate them to capture the resulting vapors. This method was called Py-GC-MS and it was particularly criticized because Py-GC-MS was found to be unsuitable for the identification of polyethylene due to constant interference.

The problem is that some low-molecular-weight compounds formed during the decomposition of polyethylene and polyvinyl chloride can also arise from human fatty tissue. Before analysis, human samples are chemically treated to remove biological tissue, but if it is not completely destroyed, the results can give false positive signals about the presence of micro- and nanoplastics. Environmental chemist from the University of Queensland in Australia, Cassandra Rauert, notes that the results of some studies are simply impossible to believe.

“I have not seen evidence that particles between 3 and 30 micrometers in size can enter the bloodstream. Based on what we know about actual exposure to plastic in our daily lives, it is biologically unlikely that this mass of plastic would actually end up in these organs,” Rauert explained.

Dr. Dusan Materić from the Center for Environmental Research. Helmholtz in Germany added that “microplastic paper for the brain is a joke.” He noted that fat produces false positive results when detecting polyethylene.

“Overall, we're just in the early stages of trying to understand the potential health impacts of microplastics, and there's no blueprint for how to do it. Much of the criticism leveled at the work to date (that is, from our laboratory and others) is speculative and not supported by evidence,” Professor Matthew Campen, lead author of the brain studies, told The Guardian.

Scientists also recently discovered that metal bottle caps were found to be a "significant" source of microplastic contamination in humans. It is noted that most microplastics are contained in glass containers.