A small study has revealed the presence of tiny plastic shards and fibers in the nose tissue of human cadavers, raising concerns about the potential health impact of microplastics. The study, conducted by researchers at the Free University of Berlin, found these microplastic particles in the olfactory bulb, the region responsible for detecting odors, which is located at the base of the brain.

Lead study author Luís Fernando Amato-Lourenço explained that once these particles enter the olfactory bulb, they have the potential to translocate to other regions of the brain. The translocation process depends on various factors, including the shape and size of the particle, as well as the body's defense mechanisms.

Of particular concern is the ability of these particles to bypass the microglia cells in the blood-brain barrier, which normally protect the brain and spinal cord from harmful substances. According to Amato-Lourenço, smaller particles are more likely to bypass these protective cells compared to larger fibers.

The study has drawn attention from experts in the field, with Phoebe Stapleton, an associate professor of pharmacology and toxicology at Rutgers University, noting that she is not surprised by the findings. Stapleton believes that plastics may be present in various parts of the body, and this study adds more evidence to support that claim.

However, there is still debate within the scientific community regarding the real-world implications of such studies. Betsy Bowers, executive director of the EPS Industry Alliance, explained that issues such as definitions, precision, bias in testing methodologies, dose-response relationships, and risk assessments contribute to the lack of consensus.

Recent studies have revealed the presence of microplastics and nanoplastics in various human tissues, including the brain, testes, blood, lungs, liver, urine, feces, mother's milk, and the placenta. In fact, a previous study linked the presence of microplastics in carotid artery tissues to an increased risk of heart attack, stroke, and mortality.

Microplastics, which can range from tiny fragments to nanoplastics, have the potential to invade cells and major organs, disrupting cellular processes and depositing harmful chemicals like bisphenols, phthalates, flame retardants, PFAS, and heavy metals. Sherri "Sam" Mason, director of sustainability at Penn State Behrend, emphasized that these chemicals can even cross the placental boundary and affect unborn children.

The latest study, published in the journal JAMA Network Open, examined the olfactory bulbs of 15 human cadavers and found microplastics in eight of them. The size of the particles ranged from 5.5 micrometers to 26.4 micrometers, much smaller than those found in previous studies on organs like the placenta, kidneys, and liver.

The study, however, could not determine the source of exposure to microplastics or why some cadavers showed evidence of plastic in their noses while others did not. Amato-Lourenço suggested that local inflammation of the nasal cavity may make it easier for microplastics to penetrate.

Polypropylene was the predominant plastic found in the cadavers' olfactory bulbs, and while considered safe for human use, a recent study suggested that microplastics made of polypropylene could worsen the progression of breast cancer.

To reduce exposure to chemicals and microplastics, experts recommend minimizing the use of disposable plastics, using stainless steel and glass containers instead, avoiding microwaving food in plastic containers, and checking recycling codes for plastics that may contain phthalates. Simple changes in daily habits can contribute to minimizing exposure to microplastics and potentially reducing associated health risks.

While more research is needed to fully understand the implications of microplastic exposure, this study serves as another reminder of the pervasive nature of plastics and the importance of reducing their impact on human health and the environment.