Does plastic make us sick? Contact with microplastics may lead to immune cell death.
Amsterdam, October 25, 2019 – When immune cells attack microplastics, the immune cells die. Nienke Vrisekoop, assistant professor at UMC (University Medical Center) Utrecht, investigated the response of human immune cells to microplastics of various sizes. She presented the first results of her research at the Plastic Health Summit held in Amsterdam earlier this month. Her research is one of the fifteen short-term research projects on plastic and human health that have been made possible by grants from ZonMw.
More research is needed
We come into contact with microplastics on a daily basis and they enter our bodies in a variety of ways. It is likely that the smallest microplastics (up to 20 micrometers – the size of a cell) end up in mammalian bodies. The important question is whether these tiny plastic particles can cause damage once they enter our bodies. In 2017, research on mice demonstrated that microplastics can accumulate in certain organs such as the liver, kidneys, and intestines.
What does this mean for human health?
Vrisekoop’s research focused on how the human immune system reacts to foreign microplastics. She used human immune cells from blood and added fluorescent microplastics of different sizes (1μm and 10μm) to a petri dish, with or without a coating. The coating consisted of blood components that bind to the plastic.
Two striking results
The experiment yielded two striking results. The first result was that clean microplastics (without a coating) were left untouched by the immune cells, while those with a coating were attacked. The attacked microplastics were encapsulated by the immune cells, which is what also happens to bacteria. It was significant that the immune cells which engulfed the microplastics died in the following hours and days, while the encapsulated microplastics themselves did not change. The second result was that the smaller microplastics (those 1μm in size) were all encapsulated, regardless of whether or not they had a coating. In this case, however, the immune cells did not die.
Worried
Vriesekoop remarked to Utrecht.nieuws.nl that her research presented a “disturbing image” and that she could “[…] imagine that this would lead to an inflammatory response within the body, one wherein the immune system makes and directs more immune cells towards microplastics”. For more information, see this NOS story about the study.
