The rise of microplastic pollution over the last 50 years might be affecting our brains. A recent study revealed an alarming trend: micro- and nanoplastics found in brain tissue from postmortem samples taken between 1997 and 2024. The study also detected these tiny particles in liver and kidney samples.
Microplastics are everywhere in our bodies. They’ve been discovered in blood, semen, breast milk, placentas, and even bone marrow. While the health impacts of these particles are not entirely understood, there are links to serious conditions like strokes and heart attacks.
The researchers, led by Prof. Matthew Campen from the University of New Mexico, noted that the concentration of microplastics was about six times higher in the brains of people with dementia. However, it’s important to remember that the brain damage caused by dementia could increase these levels, so no direct link should be assumed.
Microplastics come from broken-down plastic waste and have polluted even the most remote places on Earth, from the tops of mountains to the depths of the ocean. People can ingest these tiny particles through food and water, or they can breathe them in.
Another study recently found higher levels of microplastics in the placentas of premature babies. Additionally, it was noted that microplastics could block blood vessels in mice brains, leading to neurological damage, although human blood vessels are much larger.
This new research, published in Nature Medicine, involved analyzing samples from 28 people who died in 2016 and 24 who died in 2024, all in New Mexico. The results showed significantly more microplastics in brain tissues from the later group. Furthermore, by examining samples from people who died between 1997 and 2013 on the US east coast, a clear increase in brain microplastic contamination was noted over the years.
The most common type of plastic found was polyethylene, which is often used in shopping bags and packaging materials, making up 75% of the total microplastics detected. Most of the particles observed in the brain were tiny flakes. Interestingly, the concentrations in organs did not appear to depend on the person’s age, cause of death, sex, or ethnicity.
However, the study had its limitations. It analyzed only one sample from each organ, leaving some variability unexamined. Different results could also happen due to geographical differences between the two locations studied.
The researchers emphasized the urgent need to understand how these microplastics enter, accumulate, and affect human bodies, especially the brain. Prof. Tamara Galloway from the University of Exeter, who was not part of the research, pointed out that the significant increase in brain microplastics—about 50% over eight years—mirrors the rising production of plastics. This indicates that reducing environmental microplastic contamination could lower human exposure, highlighting the importance of innovations to combat this issue.
Prof. Oliver Jones from RMIT University in Australia echoed similar sentiments, cautioning that while the study is intriguing, the small sample size and the challenges of analyzing tiny particles could affect the results. Care should be taken when interpreting the findings.