A certain surface structure (biomolecular corona) was crucial in enabling plastic particles to pass into the brain.
Microplastics can breach the blood-brain barrier, causing ill health
Microplastics have become ubiquitous in our environment and more and more data are emerging of their potential harm to our health. Last year scientists discovered that these minute particles can enter our bloodstream and potentially accumulate in our organs over time.
Now comes research confirming that tiny plastic particles can breach the brain-blood barrier, a network of blood vessels and tissue that protects the brain from toxins and pathogens.
This could have grave implications for our health, especially as these particles keep on building up in our bodies.Microplastics can cause inflammation in the brain, leading to neurological disorders like Alzheimer’s disease.
“Humans are continuously exposed to polymeric materials such as in textiles, car tires and packaging. Unfortunately, their break down products pollute our environment, leading to widespread contamination with micro- and nanoplastics,” write the scientists, who work in Austria and Hungary.
“The blood-brain barrier (BBB) is an important biological barrier that protects the brain from harmful substances,” they explain. “We show that nanometer sized particles — but not bigger particles — reach the brain within only 2 hours after gavage.”
The researchers realized this after giving mice micro- and nanoplastics (MNPs) from polystyrene, a type of plastic widely used commercially such as in food packaging, and then examined the animals.
“With the help of computer models, we discovered that a certain surface structure (biomolecular corona) was crucial in enabling plastic particles to pass into the brain,” says Oldamur Hollóczki, a scientist at the University of Debrecen in Hungary.
“In the brain, plastic particles could increase the risk of inflammation, neurological disorders or even neurodegenerative diseases such as Alzheimer’s or Parkinson’s,” adds his colleague, Lukas Kenner, a researcher at the Medical University of Vienna in Austria.
Nanoplastics are less than 0.001 millimetres in size and can enter the food chain through sources such as packaging for both food and liquids.
According to a previous study, the scientists note, people who drink between 1.5 liters and 2 liters of water a day from plastic bottles will end up ingesting around 90,000 plastic particles in a year. “However, drinking tap water instead can – depending on the geographical location – help reduce this figure to 40,000,” the University of Vienna says.
The effects of these microplastics circulating within our bodies have yet to be fully understood. In the meantime, though, we will need to “minimise the potential harm of micro- and nanoplastic particles to humans and the environment,” Kenner stresses.
“[I]t is crucial to limit exposure and restrict their use while further research is carried out into the effects of MNPs,” the scientist says.
