Plastic, the stuff that makes up a variety of things like our coffee cups to smartphones, gets a bad rap for being harmful to the environment and wildlife around us. But as the use of plastic grows, researchers are increasingly finding that this material may also be affecting our own health in ways we never thought of.
After finding microplastics in our blood in 2022, researchers have tried to understand what ill effects this might have on our health. Now, one team has uncovered how microscopic fragments of weathered plastics may increase inflammation in the brain.
“Our research reveals that weathered microplastics (WMPs) exhibit a more pronounced inflammatory effect in the brain compared to virgin microplastics (VMPs),” says Janbolat Ashim, the lead author of a study published in the journal Environmental Research.
Weathered microplastics are plastics that have broken down after exposure to sunlight and air.
Based at the Daegu Gyeongbuk Institute of Science and Technology in South Korea, Ashim’s work shows that microplastics ingested by animals orally can make their way to the brain within a week. This means microplastics, unlike previously believed, can cross the blood-brain barrier.
His team also found evidence that this led to an increase in inflammation of brain cells.
“Brain inflammation represents just the initial phase of brain impact,” Ashim explained to Happiest Health. “Once microplastics enter the brain, they have the potential to accumulate over time because they are resistant to biological degradation.”
It is this accumulation that experts are worried about. In their testing in the lab and in animal models, the researchers from Daegu Gyeongbuk Institute found that exposure to WMPs led to an increase in the genes related to inflammatory responses in blood serum leading to brain cell injury and death.
The researchers also observed the presence of macrophages in the brain, indicating an increase in brain inflammation. Macrophages are immune cells known for engulfing foreign objects.
When quizzed about how microplastics could affect our brain health, Dr Mayank Detroja, a neurologist at Sahaj Child Neurology and Epilepsy Centre in Surat, said there are studies showing evidence that these particles trigger oxidative stress, harming brain cells and disrupting vital neurotransmitters.
These tiny microplastic particles can interfere with brain enzymes, including acetylcholinesterase, crucial for nerve cell communication. Acetylcholinesterase is required for the normal functioning of the brain and a lack of this enzyme can lead to conditions like Alzheimer’s disease, Parkinson’s disease, and neuromuscular disorders.
“These plastics can breach the protective barrier around the brain,” Dr Detroja notes alarmingly. While scientists continue to uncover the full effect of microplastics on our health, people should look at ways to reduce their exposure to plastics to safeguard their long-term brain health, he adds.
Another study, conducted by the University of Rhode Island in the USA, observed decreased levels of glial fibrillary acidic protein (GFAP) in mice brains, following exposure to microplastic particles via drinking water.
The decline in GFAP levels implies potential early-stage brain changes akin to those observed in conditions such as Alzheimer’s or major depressive disorders, the researchers noted. However, further investigation is necessary to precisely understand the implications of this reduction in GFAP levels and its potential effects on brain function and health, they added.
While this highlights the need for more conclusive evidence on the ways in which microplastics affect our health, it adds to the list of reasons to increase awareness and regulation of plastic pollution in the environment.
