Can microplstics damage the brain?

It has been estimated that each person consumes on average up to 5 grams of microplastics per day present in water and food. This disturbing and shocking information has been verified in many research centers for many years. Researchers at the University of New Mexico (United States) have made another attempt to determine the impact of this type of pollution on the human digestive system. In the process, they discovered that microplastic particles can migrate from the intestines to other organs. They are also found on the skin, in hair, saliva and in fecal samples. Microplastic particles that are less than 0.1-5,000 microns in size have also been discovered in a newborn's first feces, known as meconium. This could be evidence that microplastics cross the blood-blood barrier.

The findings, published in the journal Environment Health Perspectives, indicate that microplastic particles can penetrate the blood and, via this route, many other organs, including the brain, wreaking havoc on health. A university team from New Mexico, led by gastroenterologist Prof. Eliseo Castillo, set as the goal of the study to see if, in what amount and how microplastic crosses the intestinal barrier. As part of the research experiment, mice were given water containing microplastic for a month, in proportions similar to those drank by humans. After several weeks, physical changes were observed in the mice and plastic particles were detected in some tissues. This supports the supposition that they crossed the intestinal barrier and entered other tissues. The plastic microparticles migrated from the intestines to the liver, kidneys and brain. The implication is that they affect more than just the gastrointestinal tract.

During the study, it was also shown that the migration of microplastic inside the body causes chemical reactions in the cells of affected tissues. These are dependent on the concentration and type of plastic and, as previous studies have indicated, affect the immune system, which releases inflammatory molecules when exposed to microplastic particles. It has been shown that the harmful effects of microplastics are caused both by the composition of the substance and from the fact that bacteria, fungi and other pathogens, including drug-resistant ones, can be deposited on the surface of microplastics absorbed by the body, which poses a real threat to health. Back in 2021, the first study was published in the scientific journal Cell Biology & Toxicology, which confirms that when macrophages encounter and "ingest" microplastics, their function is altered and inflammatory molecules are released.

Professor Castillo therefore asks whether exposure to microplastics can exacerbate changes in a patient's existing disease. Especially in chronic diseases such as inflammatory bowel disease, celiac disease, obesity and steatohepatitis. The scientist stresses that it is most likely that microplastics have a significant impact on the digestive system and through this pathway enter other organs. One of the evidences for this thesis is the fact that the mice in the study were exposed to microplastics for only four weeks, and already for this short period of time it left traces in their bodies. Humans, on the other hand, come into contact with these harmful substances continuously through contaminated water and food, but also through objects and materials used in daily life. The next step in the research, will be to determine whether metabolic changes caused by the "consumption" of microplastics play a role in regulating the immune system, in metabolism or in the dysfunction of many organs, and to check the mechanism of influence on the exacerbation of inflammation.

The team of researchers intends to focus on answering the question of how the diet contributes to microplastic absorption, depending on whether it is richer in fat, fiber, etc., and whether they affect changes in the intestinal microflora.