Microplastics and Lung Cancer: Study Finds Higher Particle Burden in Patients With Lung Cancer

A new study presented at the European Respiratory Society Congress found a higher microplastic burden in lung cancer patients. Here is what researchers discovered and what the findings mean.

Microplastics are increasingly being detected in the human body, raising questions about how long-term exposure to these tiny plastic particles may affect human health. Now, new research has found that people diagnosed with lung cancer had a higher burden of microplastic particles in their respiratory samples than people without lung cancer.

The findings were presented at the European Respiratory Society (ERS) Congress 2026 in Barcelona, Spain. Researchers say the results add to growing evidence that microplastics can be present in the human respiratory system. However, the study does not establish that microplastics cause lung cancer.

What Did the Microplastics and Lung Cancer Study Find?

Researchers led by Ilias E. Dimeas, M.D., from University College Dublin School of Medicine and the University of Thessaly in Greece, examined samples from 100 adults undergoing diagnostic bronchoscopy.

Half of the participants were subsequently diagnosed with lung cancer, while the other 50 participants did not have a malignant lung condition.

The researchers analyzed paired samples of bronchoalveolar lavage (BAL) and lung tissue. BAL is a procedure in which fluid is introduced into part of the lung and then collected for laboratory analysis. It can provide information about cells, microorganisms, and other substances present within the airways and lungs.

Across the study population, researchers identified 232 microplastic particles. At least one type of microplastic was detected in 70 percent of the participants.

Importantly, the overall microplastic burden was higher among participants with lung cancer compared with those who did not have malignancy.

The researchers also found that microplastics were detectable in BAL samples from 66 percent of people with lung cancer, compared with 46 percent of participants without cancer.

These findings suggest that people with lung cancer may have a greater accumulation of microplastic particles in certain parts of the respiratory system. However, several important questions remain unanswered.

What Are Microplastics?

Microplastics are extremely small pieces of plastic, generally resulting from the breakdown of larger plastic products or being produced as small particles for specific applications.

People can encounter microplastics through a variety of environmental sources. They may be present in food, drinking water, household dust and air. Because some particles are small enough to become airborne, researchers have become increasingly interested in whether people can inhale them and where those particles may accumulate.

The respiratory system is particularly relevant because inhaled particles can travel through the airways and, depending on their size and characteristics, potentially reach deeper areas of the lungs.

Scientists are still investigating how the body responds to microplastics and whether repeated exposure can have meaningful health effects.

Does This Mean Microplastics Cause Lung Cancer?

No.

One of the most important points about this research is that it cannot demonstrate a cause-and-effect relationship between microplastics and lung cancer.

The study found that microplastic levels were higher among people with lung cancer. This is an association, not proof that exposure to microplastics caused the cancer.

There are several possible explanations for the results.

Microplastics could potentially influence biological processes such as inflammation, oxidative stress or other changes within lung tissue. These mechanisms are areas of scientific interest, but additional research is needed to determine whether they play a meaningful role in cancer development.

Another possibility is that lung cancer or changes associated with diseased lung tissue could affect how particles are retained, cleared or distributed.

As Dimeas explained, the researchers cannot determine from this type of study why more microplastics were found in samples from people with lung cancer.

Researchers Found Differences Between Lung Samples

The study also produced an interesting finding concerning where microplastics were detected.

Researchers observed a strong relationship between total microplastic counts and the number of particles detected in BAL samples. However, this relationship was not observed in the same way with lung tissue samples.

This suggests that microplastic distribution may differ between compartments of the respiratory system.

Among participants with lung cancer, researchers reported a significant inverse correlation between microplastic counts in BAL and tissue samples. In simple terms, participants with higher particle counts in one type of sample did not necessarily have higher counts in the other.

This could indicate that microplastics are not distributed uniformly throughout the lungs.

The researchers also used Raman characterization, a technique that can help identify and analyze particles based on their physical and chemical characteristics. They reported that particle distribution differed according to diagnosis, with epithelial malignancies showing an enrichment of particles identified through fluorescence-only analysis.

These findings may provide clues for future research into how microplastics behave in different lung environments.

Why Is This Research Important?

Interest in microplastics and human health has increased as scientists have identified plastic particles in different human tissues and biological samples.

The lungs are an important area of study because they are directly exposed to the outside environment through breathing.

The new research does not prove that microplastics are responsible for lung cancer. However, it highlights the need for larger studies that can investigate whether there is a biological connection between microplastic exposure and respiratory disease.

Future research may need to examine people over longer periods and account for other established lung cancer risk factors, including tobacco exposure, occupational exposures, air pollution, age, genetics and other environmental factors.

Researchers may also need to determine whether certain types, sizes or shapes of microplastic particles are more likely to remain in lung tissue.

What Should People Do About Microplastics?

At present, the findings do not provide a basis for people to assume that microplastic exposure will cause lung cancer.

There are also no established clinical recommendations specifically designed to prevent lung cancer by eliminating everyday microplastic exposure.

People should continue to focus on proven strategies for reducing lung cancer risk. For example, avoiding tobacco use and quitting smoking remain among the most important steps people can take to protect lung health.

Individuals should also follow established medical screening recommendations based on their age, smoking history and other personal risk factors.

Anyone experiencing persistent respiratory symptoms, such as a chronic cough, unexplained weight loss, coughing up blood, chest pain or ongoing shortness of breath, should speak with a healthcare professional rather than attempting to determine the cause independently.

More Research Is Needed

The discovery of a higher microplastic burden in lung cancer patients is an intriguing finding, but it represents an early step in understanding the relationship between plastic particles and human health.

The study involved only 100 adults, and participants were examined during diagnostic bronchoscopy rather than followed prospectively over many years. This makes it difficult to determine whether microplastic exposure preceded the development of cancer or whether cancer-related changes influenced particle retention.

Larger and longer-term studies will be necessary to clarify the relationship.

For now, the main takeaway is that microplastics were detected more frequently and in greater amounts in samples from patients with lung cancer in this study, but researchers have not established that microplastics cause lung cancer.

As scientists continue investigating the health effects of environmental plastic exposure, studies such as this may help identify important questions for future research.

Source

European Respiratory Society (ERS) Congress 2026, based on research led by Ilias E. Dimeas, M.D., from University College Dublin School of Medicine and the University of Thessaly.

Medical Disclaimer

This article is for informational and educational purposes only. The findings discussed are from research presented at a scientific meeting and should not be interpreted as proof that microplastics cause lung cancer. Research presented at a medical congress may be preliminary and can change as further analysis and peer-reviewed publication become available.