Microplastics are increasingly detectable in human lung tissue, according to research led by Dr. Ilias Dimeas at University Hospital of Larissa in Thessaly, Greece, raising new scientific questions about environmental pollution and respiratory health. Investigators examining 100 patients undergoing bronchoscopies found detectable plastic particles in 70 percent of the overall participants. The findings highlight the growing ubiquity of airborne plastic debris, though researchers caution that biological mechanisms linking these particles to diseases like lung cancer remain under investigation.
Patient Cohort and Bronchoscopy Sample Collection Methods
The study evaluated 100 individuals who underwent bronchoscopies to investigate various lung symptoms at University Hospital of Larissa, according to Dr. Ilias Dimeas. Each patient provided a lung-wash sample, where a saline solution flushed a section of the lung to capture cells and suspended material. For half of the participants, physicians also extracted a small sample of actual lung tissue.
Laboratory analysis of these samples identified a total of 232 microplastic particles across the cohort. Polypropylene and polyethylene emerged as the most prevalent types of plastic. These materials appear widely in everyday consumer goods, textiles, household items, and modern packaging.
Microplastic Burden Comparisons in Lung Cancer Patients
Of the 100 patients evaluated in the research, 50 received a subsequent diagnosis of lung cancer while the other 50 did not, according to the study data. When researchers analyzed lung wash and tissue samples together, patients diagnosed with lung cancer showed a higher likelihood of detectable microplastics and a greater overall microplastic burden compared to individuals without cancer. Specifically, lung cancer patients exhibited higher rates of detectable microplastics in their lung wash samples at 66 percent, versus 46 percent for non-cancer patients.
Comparing lung wash and tissue samples from the same individuals revealed an inverse spatial relationship. Patients with higher microplastic concentrations in their lung washes tended to have lower concentrations in their corresponding tissue samples, and vice versa. Because lung wash samples collect particles from open airspaces while tissue samples capture embedded material, Dr. Dimeas noted that this distribution suggests microplastics do not disperse evenly throughout the lung, and different regions may retain particles differently.
Did you know?
Lung cancer remains the most common type of cancer globally and the leading cause of cancer deaths, generating roughly 2.5 million cases and 1.8 million deaths annually, according to Professor Barbara Hoffmann of the University of Düsseldorf.
Scientific Uncertainties and Ongoing Respiratory Research
While the data establishes a clear correlation between microplastic presence and lung cancer diagnoses in this cohort, causation remains unproven. Dr. Dimeas explained that microplastics might contribute to inflammation or other biological processes connected to diseases like cancer, but diseased lungs could alternatively retain particles differently than healthy tissue. The research team has already initiated further laboratory experiments to examine how specific plastic types interact directly with human lung cells.
In addition to cancer research, Dr. Dimeas and his colleagues are currently analyzing samples from patients suffering from chronic lung diseases. This ongoing work aims to determine whether microplastics play a functional role in lung scarring and disease progression.
Broader Public Health Context and Environmental Factors
Smoking continues to represent by far the primary cause of lung cancer globally, according to Professor Barbara Hoffmann, Chair of the European Respiratory Society’s Advocacy Council. Air pollution is also firmly established as a contributor to lung cancer and other respiratory conditions such as asthma and chronic obstructive pulmonary disease (COPD). Hoffmann, who was not involved in the Thessaly study, noted that research regarding microplastic health impacts remains in early stages.
“We need more research to fully understand their potential role in lung diseases, including cancer,” Hoffmann stated regarding airborne microplastic infiltration. “In the meantime, we advocate for the fundamental human right to breathe clean air, and this includes air that is not polluted with microplastics.”
Frequently Asked Questions
What types of microplastics were most frequently found in the lungs?
Polypropylene and polyethylene were identified as the most common plastic types in the samples, originating from everyday items like packaging and textiles.
Did the study prove that microplastics cause lung cancer?
No. While cancer patients showed a higher microplastic burden, researchers emphasize that it remains unclear whether plastics contribute to disease development or if diseased lungs simply retain particles differently.
How were the lung samples collected?
What are researchers investigating next?
Scientists are conducting laboratory experiments to observe how plastics interact with lung cells and are analyzing samples from patients with chronic lung conditions to check for links to scarring.
Stay Informed on Respiratory Health
Subscribe to our newsletter for the latest updates on environmental science, medical research, and public health policy.
Keep reading