KINGSTON, R.I. — Microplastics have become one of the globe’s most widespread pollutants, contaminating air, water, and even our food sources. While the harmful effects of these tiny particles on marine life are widely recognized, the impact on mammals, including humans, remains largely uncharted. An alarming study by University of Rhode Island (URI) scientists found that exposure to microplastics could lead to neurological behavioral changes, including dementia-like symptoms.
Researchers studied the effects of microplastics on the behavior, immune response, and tissue accumulation in mice. Their discoveries were concerning.
“Current research suggests that these microplastics are transported throughout the environment and can accumulate in human tissues; however, research on the health effects of microplastics, especially in mammals, is still very limited,” says study author Jaime Ross, an assistant professor of biomedical and pharmaceutical sciences at the Ryan Institute for Neuroscience and the URI College of Pharmacy, in a university release. “This has led our group to explore the biological and cognitive consequences of exposure to microplastics.”
For three weeks, the team gave mice drinking water infused with microplastics. They found behavior reminiscent of human dementia, especially in older mice. Furthermore, these mice had noticeable changes in immune markers in their liver and brain tissues.
“To us, this was striking. These were not high doses of microplastics, but in only a short period of time, we saw these changes,” notes Ross. “Nobody really understands the life cycle of these microplastics in the body, so part of what we want to address is the question of what happens as you get older. Are you more susceptible to systemic inflammation from these microplastics as you age? Can your body get rid of them as easily? Do your cells respond differently to these toxins?”
The research didn’t stop at behavior. URI scientists dissected major organs like the brain, heart, liver, and lungs. They discovered microplastics had penetrated every organ, even those that should be shielded from such particles, and were present in bodily waste.
“Given that in this study the microplastics were delivered orally via drinking water, detection in tissues such as the gastrointestinal tract, which is a major part of the digestive system, or in the liver and kidneys was always probable,” explains Ross. “The detection of microplastics in tissues such as the heart and lungs, however, suggests that the microplastics are going beyond the digestive system and likely undergoing systemic circulation. The brain blood barrier is supposed to be very difficult to permeate. It is a protective mechanism against viruses and bacteria, yet these particles were able to get in there. It was actually deep in the brain tissue.”
Another critical discovery was the decline of a vital brain protein named GFAP.
“A decrease in GFAP has been associated with early stages of some neurodegenerative diseases, including mouse models of Alzheimer’s disease, as well as depression,” says Ross. “We were very surprised to see that the microplastics could induce altered GFAP signaling.”
Ross noted, “A decrease in GFAP has been associated with early stages of some neurodegenerative diseases, including mouse models of Alzheimer’s disease, as well as depression.”
The study is published in the International Journal of Molecular Science.
Lea la versión en español en EstudioRevela.com: La exposición a microplásticos podría provocar síntomas similares a la demencia.