Microplastics have been detected throughout the human body, from the bloodstream to the brain. Now, new research is examining whether the presence of these tiny plastic particles could be associated with neurological disease.
A study published in Brain Communications in August 2026 found higher concentrations of nano- and microplastics in the blood and cerebrospinal fluid of patients with amyotrophic lateral sclerosis (ALS) compared with individuals without neurological disease. These findings add to growing questions about how widespread microplastic exposure may affect the human nervous system.
Measuring Microplastics in the Central Nervous System
Researchers from several universities and medical institutions in Italy and the United States examined 44 people in Northern Italy: 24 patients who had recently been diagnosed with ALS and 20 controls who had undergone neurological testing but were ultimately found not to have neurological disease.
The researchers analyzed both serum and cerebrospinal fluid (CSF), the fluid surrounding the brain and spinal cord, for nano- and microplastic particles between 0.1 and 10 micrometers in size.
Microplastics were detected in both serum and CSF samples, with particle sizes generally measuring only a few micrometers or less. Researchers also found a strong positive relationship between microplastic concentrations in serum and CSF, meaning people with higher concentrations of microplastics in their blood generally also had higher concentrations in their cerebrospinal fluid.
ALS Patients Had Higher Microplastic Concentrations
One of the study’s most notable findings was the difference in microplastic concentrations between ALS patients and controls.
Median microplastic concentrations in serum were 1,513.7 particles/mL among ALS patients and 1,278.7 particles/mL among controls. The difference was even greater in cerebrospinal fluid, with 1,022.0 particles/mL among ALS patients and 532.1 particles/mL among controls.
These results show that the median concentration of microplastics in cerebrospinal fluid was nearly twice as high among ALS patients.
Researchers also observed a positive relationship between increasing microplastic concentrations in CSF and the odds of having ALS. In serum, a positive association appeared at concentrations above approximately 2,500 particles per milliliter.
Among the ALS patients, higher serum microplastic concentrations were also associated with higher levels of neurofilament light chain, or NfL, a biomarker associated with damage to nerve-cell axons.
What Does This Mean?
The study provides another piece of evidence that extremely small plastic particles can be present in parts of the human body once considered relatively protected from environmental contaminants. Previous research cited by the authors has detected microplastics in human brain tissue and cerebrospinal fluid, while laboratory and animal research has raised concerns about the potential neurotoxicity of particularly small particles.
The researchers concluded that their findings warrant further investigation into whether nano- and microplastics could play a role in motor-neuron degeneration and other neurological processes.
Reducing Microplastics at the Source
Scientists are still working to understand exactly what long-term microplastic exposure means for human health. But the continued detection of microplastics throughout the human body reinforces a broader challenge: these particles have become deeply embedded in our environment.
The number one source of microplastic pollution is synthetic textiles.
Every time synthetic clothing is washed, friction can release tiny plastic fibers into wastewater. Without effective filtration, some of those fibers can ultimately make their way through wastewater systems and into the environment.
Reducing that pollution before it enters our waterways is one way to address the problem at its source.
The CLEANR Microplastic Filter for Washing Machines captures 90%+ of microplastics released during laundry, helping prevent millions of fibers from leaving the home and entering wastewater.
Research into the potential health effects of microplastics is still developing, and studies like this one do not yet provide all the answers. But as scientists learn more about where microplastics travel and how they interact with the human body, preventing unnecessary plastic pollution remains an important step toward cleaner water and a cleaner environment.
Read the full study here: https://academic.oup.com/braincomms/article/8/4/fcag296/8749471