April 27, 2023
Author: Manish Verma
Editor: Dr. Jitendra Kumar Sinha
Did you know that you may already have microplastics in your brain? Yes, you read that right. Tiny particles of plastic, so small they’re invisible to the naked eye, have been found in the brains of both animals and humans. How did they get there? And what are the risks to our brain health? In this article, we’ll explore the invisible threat of microplastics and their potential impact on our brains.
In the past 70 years, there has been a significant increase in global plastic production, resulting in its widespread presence in the environment, leading to the notion of living in a “plastic world”. From textiles to car tires and packaging, polymeric materials are present in almost every aspect of our daily lives. However, the breakdown products of these materials have resulted in the widespread contamination of our environment with microplastics and nanoplastics (MNPs). While these tiny particles have long been recognized as pollutants, recent studies have shown traces of MNPs in human organs, blood, brain and even placenta of developing embryos.
Microplastics and nanoplastics (MNPs) are defined by their small size. Microplastics are typically less than 5 millimeters in diameter, while MNPs are smaller than 100 nanometers. This size range allows them to easily enter the human body through various exposure routes and poses potential risks to human health. Furthermore, their small size makes them difficult to detect and remove from the environment, leading to widespread contamination of water, soil, and air.
Due to their small size, these particles can enter the human body through various exposure routes such as ingestion, inhalation, and dermal contact. Once inside the body, microplastics can accumulate and persist in various organs, leading to potential adverse effects on human health. Studies have linked microplastic exposure to inflammatory responses, oxidative stress, and other health issues.
Source: Sangkham et al., 2022
One of the most important biological barriers protecting the brain from harmful substances is the blood-brain barrier (BBB). However, a recent study published in the journal ACS Nano discovered that nanometer-sized microplastic particles can reach the brain within just two hours after ingestion by mice. This finding is alarming, as it suggests that microplastics can cross the BBB and accumulate in the brain.
To understand how microplastics penetrate the BBB, the study utilized coarse-grained molecular dynamics simulations. The simulations demonstrated that the composition of the biomolecular corona surrounding the plastic particles played a critical role in their ability to pass through the BBB. Specifically, cholesterol molecules were found to enhance the uptake of these contaminants into the membrane of the BBB, while the protein model inhibited it. These opposing effects could explain the passive transport of the particles into the brain.
Source: Kopatz et al., 2023
Although the study was conducted on mice, it has significant implications for human health. The presence of microplastics in the brain raises concerns about their potential impact on brain function and health. As MNPs accumulate in the brain, they may cause inflammation, oxidative stress, and neurotoxicity. These effects could lead to a range of neurological disorders, including Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis.
Moreover, microplastics are pervasive in our environment, and we are all exposed to them. Microplastics have been detected in drinking water, seafood, and even the air we breathe. We are therefore all at risk of accumulating microplastics in our bodies, including our brains.
So, what can we do to protect ourselves from this invisible threat?
Firstly, we need to be more aware of the sources of microplastics and take steps to reduce our exposure. This can include avoiding single-use plastics, using natural fibers instead of synthetic ones, and reducing our consumption of processed foods, which often come in plastic packaging.
Secondly, we need to advocate for stricter regulations on the use and disposal of plastics. This can include advocating for bans on single-use plastics and increased recycling programs.
Finally, more research is needed to better understand the health impacts of microplastics on the brain and other organs. This research can help inform policies and interventions to reduce our exposure and protect our health.
In conclusion, microplastics are an invisible threat to our brain health. The discovery that these particles can cross the BBB and accumulate in the brain raises significant concerns about their impact on neurological function and health. We must take steps to reduce our exposure to microplastics and advocate for stricter regulations to protect our health and the environment.
References
- Kopatz V, Wen K, Kovács T, Keimowitz AS, Pichler V, Widder J, Vethaak AD, Hollóczki O, Kenner L. Micro- and Nanoplastics Breach the Blood–Brain Barrier (BBB): Biomolecular Corona’s Role Revealed. Nanomaterials. 2023; 13(8):1404. https://doi.org/10.3390/nano13081404
- Leslie, H. A., van Velzen, M. J. M., Brandsma, S. H., Vethaak, A. D., Garcia-Vallejo, J. J., & Lamoree, M. H. (2022). Discovery and quantification of plastic particle pollution in human blood. Environment international, 163, 107199. https://doi.org/10.1016/j.envint.2022.107199
- Mohamed Nor, N. H., Kooi, M., Diepens, N. J., & Koelmans, A. A. (2021). Lifetime Accumulation of Microplastic in Children and Adults. Environmental science & technology, 55(8), 5084–5096. https://doi.org/10.1021/acs.est.0c07384
- Sangkham, S., Faikhaw, O., Munkong, N., Sakunkoo, P., Arunlertaree, C., Chavali, M., Mousazadeh, M., & Tiwari, A. (2022). A review on microplastics and nanoplastics in the environment: Their occurrence, exposure routes, toxic studies, and potential effects on human health. Marine pollution bulletin, 181, 113832. https://doi.org/10.1016/j.marpolbul.2022.113832