Over the last few years, studies have increasingly highlighted concerns about the health consequences of consuming food, cosmetics, and other products stored in plastic due to the ingestion and absorption of microplastics and nanoplastics.

Microplastics are plastic particles with a diameter of less than 5 mm, and nanoplastics are generally considered plastic particles smaller than 1 micrometer in size and up to 1000 nanometers in range. While definitive health impacts remain unclear, research has identified several potential risks from microplastics and nanoplastics in the human body. Potential health risks include inflammation and cellular damage, endocrine disruption, toxicity, and gastrointestinal and metabolic effects. A 2022 report by researchers from the University of Hull and Castle Hill Hospital identified microplastics in lung tissue from living patients, marking the first time such particles were found in live human lungs. They analyzed 13 lung tissue samples from surgical patients and detected plastic particles in 11, including 12 different types commonly found in household materials. Surprisingly, microplastics were discovered not only in the upper lungs but also in the lower regions, where airways are narrower, and higher levels were found in male patients; however, the health effects of these particles remain unknown, warranting further research (Jenner et al., 2022).

A recent study found microplastics in the brains of mice within hours of consumption (Huang et al., 2025). Using advanced imaging techniques, researchers observed that microplastics entered the bloodstream and eventually reached the brain, where they were captured by immune cells, leading to blockages. The affected mice exhibited memory loss, motor skill deficits, and reduced endurance. Indeed, mouse and human anatomy differ, but the urgent need for further studies on the impact of microplastics on brain health remains.

There is growing concern among researchers that microplastics and nanoplastics could cross the blood-brain barrier, leading to neuroinflammation and cellular dysfunction. Could these particles be responsible for some dementia-like symptoms seen in adults?

Read the published study from the team of environmental biologists online in Science Advances.