Related Experiment Video
Updated: Jul 19, 2025

Murine Nasal Lavage Fluid Collection without Blood Contamination
Published on: July 11, 2025
Nasal lavage technique reveals regular inhalation exposure of microplastics, not associated from face mask use
A Torres-Agullo1, A Karanasiou1, S Lacorte1
1Institute of Environmental Assessment and Water Research of the Spanish Research Council (IDAEA-CSIC). Jordi Girona 18-26, 08034 Barcelona, Spain.
Abstract:
During the COVID-19 pandemic, the use of face masks has been a worldwide primary protection measure to contain the spread of the virus. However, very little information is known about the possible inhalation of microplastics (MP) from wearing masks. This pilot study evaluates the presence of MP accumulated in nasal cavities through the nasal lavages technique. Six different commercial face masks were tested in 18 participants during five working days (8 h use/day). Eight different polymers (polystyrene, polyamide, poly(ethylene - propylene) diene monomer, polyester, polyethylene, polyvinylidene fluoride, polypropylene, and polyvinyl chloride) predominantly within the 20-300 µm size were detected in nasal lavages, with an average concentration of 28.3 ± 15.6 MP/5 mL nasal solution. Results demonstrate that MP in the nasal cavity are not associated to face mask use but rather to general exposure to airborne MP. We highlight the use of nasal lavages to evaluate human inhalation of MP and associate it to potential sources and risks.
Insights
Microplastic (MP) inhalation from face masks is minimal. Nasal lavages reveal airborne MP exposure, not mask-specific contamination, highlighting a new method for MP inhalation studies.
Area of Science:
- Environmental Science
- Toxicology
- Public Health
Background:
- Face masks are crucial for COVID-19 containment.
- Potential microplastic (MP) inhalation from masks is under-researched.
- Understanding MP exposure routes is vital for public health.
Purpose of the Study:
- To investigate microplastic (MP) presence in nasal cavities.
- To determine if face mask use contributes to MP inhalation.
- To assess nasal lavage as a method for MP exposure evaluation.
Main Methods:
- Pilot study involving 18 participants over five working days.
- Analysis of nasal lavages for microplastics (MPs) after 8-hour daily mask use.
- Identification of polymer types and sizes (20-300 µm) using specific techniques.
Main Results:
- Eight polymer types were detected in nasal lavages.
- Average MP concentration was 28.3 ± 15.6 MP/5 mL nasal solution.
- MP presence was linked to general airborne exposure, not specifically to face mask use.
Conclusions:
- Nasal microplastic (MP) accumulation is not significantly associated with face mask usage.
- Airborne microplastic (MP) exposure is a more likely source of nasal contamination.
- Nasal lavage is a viable technique for assessing human microplastic (MP) inhalation and potential risks.

