Ways to detect nano-plastics in human organs developed as scientists raise health concerns over plastic pollution
Plastic fragments are everywhere, from the food we eat and the water we drink to the air we breathe. Its universal presence has raised questions on whether micro and nano-plastics settle in human organs and tissues, and threaten human health.
Researchers have taken the first step to answer these questions. In their new study, the team has developed a method to detect tiny plastic fragments in human organ samples. Plastics break down into microplastics, which measure less than 5 micrometers in diameter, and are largely invisible to the naked eye. Nanoplastics are even smaller measuring 0.001 micrometers, the researchers said.
Previously, scientists found traces of microplastics in human poop samples, confirming they enter the body. There is also evidence that aquatic organisms unwittingly consume microplastics. Eating contaminated seafood could expose humans to the pollutant as well.
The health impacts, however, are not clear. Our bodies respond to a foreign object by triggering inflammation, which may lead to more severe health issues, including cancer. "Plastics have been demonstrated to cause adverse effects in the environment and animals including mammals," Dr. Rolf Halden from Arizona State University, told MEA WorldWide (MEAWW). He is one of the authors of the study.
"You can find plastics contaminating the environment at virtually every location on the globe, and in a few short decades, we've gone from seeing plastic as a wonderful benefit to considering it a threat," Charles Rolsky, a Ph.D. student from Arizona State University, said. "There's evidence that plastic is making its way into our bodies, but very few studies have looked for it there," he added.
It is challenging to obtain information on the acculturation of microplastics in human organs, according to Dr. Halden. "Access to well-characterized samples of human tissues is one major hurdle, and a lack of methods to detect plastics that cannot be observed with the naked eye is another one," he added.
In 2019, the team of researches identified bisphenol A and other plastic building blocks called monomers in 47 human tissue samples of liver and adipose [fat] tissue. Bisphenol A, which is used in building plastics, is controversial because of its links with health issues. "Here we report a new method to directly interrogate human tissues for the presence of microplastics," Dr. Halden said, adding that they have also developed an online tool, which can calculate the mass and volume of the contaminant and record the locations of any given detections. It can help inform if tiny plastic fragments settle in human tissues.
"We look forward to sharing the online conversion and reporting tool we developed with other researchers and citizen scientists so that we are measuring plastic pollution using one and the same yardstick (metric), which will help to directly compare and analyze results from different studies," he noted.
As for health impacts, researchers are not sure. According to Varun Kelkar, a Ph.D. student at Arizona State University, gaining more insight into the plastic accumulation in human tissues can pave the way for epidemiological studies that could assess its links with health conditions.
The research was presented at a meeting of the American Chemical Society.