Intranasal Therapeutic Strategies for Mitigation of Airborne Microplastic and Nanoplastic Exposure

Abstract

Airborne microplastics (MPs) and nanoplastics (NPs) are increasingly recognized as an important route of environmental exposure. Recent studies have identified microplastics within the human olfactory bulb and have demonstrated associations between environmental particulate exposure, inflammation, oxidative stress, and neurological injury. These findings suggest that the nasal cavity may represent an important site for therapeutic intervention.

This Technical Note outlines a proposed intranasal therapeutic platform designed to support nasal mucosal health while mitigating biological interactions associated with inhaled environmental particles. The platform is intended to provide a flexible foundation for future pharmaceutical development through local anti-inflammatory effects, mucosal protection, barrier formation, particle interaction, and enhancement of mucociliary clearance. Additional studies will be required to evaluate safety, mechanism of action, and clinical utility.

  This paper is also available at: https://doi.org/10.5281/zenodo.20943717

Figure 1 illustrates the human inhalation pathway for airborne microplastics and nanoplastics and highlights the nasal cavity as the proposed site for local therapeutic intervention. The intranasal approach is intended primarily to support nasal mucosal health through local anti-inflammatory effects while secondarily providing barrier formation, particle interaction, sequestration, and enhancement of mucociliary clearance. Reduction of particle uptake through the olfactory pathway represents an exploratory mechanism for future investigation.

Introduction

Environmental exposure to airborne microplastics and nanoplastics has emerged as an important area of investigation in environmental health.  Following inhalation, particles may deposit throughout the respiratory tract, including the nasal cavity, where they may interact with epithelial surfaces, immune cells, and the olfactory region.   Detection of microplastics within human olfactory bulb tissue has raised important questions regarding potential transport through the olfactory pathway and possible downstream biological effects.

While engineering controls such as environmental filtration remain important exposure-reduction strategies, comparatively little attention has been directed toward therapeutic approaches that act directly at the primary biological interface of exposure—the nasal mucosa.

Proposed Therapeutic Platform

The proposed platform is designed primarily to support nasal mucosal health through localized intranasal therapy.

Unlike systemic therapies, the investigational concept focuses on local biological activity within the nasal cavity, where inhaled environmental particles first encounter the respiratory epithelium.

Potential mechanisms include:

•        Local anti-inflammatory effects on the nasal mucosa

•        Protection of nasal epithelial surfaces

•        Support of normal mucosal barrier function

•        Mucoadhesive barrier formation

•        Interaction with inhaled microplastics and nanoplastics

•        Particle sequestration and aggregation

•        Enhancement of natural mucociliary clearance

Secondary and exploratory mechanisms include reduction of particle interaction with nasal tissues, reduction of epithelial uptake, and potential reduction of transport through the olfactory pathway. These mechanisms remain investigational and require additional nonclinical evaluation.

A Flexible Intranasal Platform

Although initially conceived for mitigation of environmental particulate exposure, the proposed platform is intended to support broader intranasal therapeutic development.

Representative formulations may include:

•        Intranasal sprays

•        Mucoadhesive gels

•        Ointments

•        Sustained-release formulations

Future embodiments may incorporate biologics, peptides, antibodies, nucleic acids, nanoparticles, lipid nanoparticles, liposomes, extracellular vesicles, small molecules, or other active therapeutic agents as appropriate.

Accordingly, the platform may ultimately support both localized nasal therapies and future intranasal drug delivery applications.

Proposed Development Strategy

Future development will focus on stepwise evaluation of safety, biological activity, and mechanism.

Representative studies include:

•        Formulation optimization

•        Human nasal epithelial cell models

•        Three-dimensional nasal mucosa models

•        Particle interaction and aggregation studies

•        Mucociliary clearance assays

•        Cytokine profiling

•        Oxidative stress biomarkers

•        Barrier integrity assessment

•        Regulatory consultation and early pharmaceutical development

These studies are intended to establish scientific rationale prior to clinical investigation.

Discussion

Intranasal therapeutic approaches represent an underexplored strategy for addressing environmental particulate exposure.  Because the nasal cavity serves as the initial biological interface for inhaled particles, locally acting therapies may offer opportunities to support mucosal health while reducing biological interaction between environmental particles and host tissues.  The concepts presented here should be regarded as a proposed therapeutic framework requiring rigorous pharmaceutical development, nonclinical investigation, and clinical evaluation.

Conclusion

Airborne microplastics and nanoplastics represent an emerging environmental health challenge with potential implications for respiratory and neurological health.  Localized intranasal therapeutic platforms provide a scientifically plausible approach for supporting nasal mucosal health while investigating strategies to reduce biological interaction with inhaled environmental particles. Continued research integrating pharmaceutical development, environmental health, and translational medicine will be necessary to determine the safety, efficacy, and clinical role of these approaches.

Public Disclosure Statement

This Technical Note serves as a public technical disclosure related to U.S. Provisional Patent Application Nos. 64/097,353 and 64/087,250, as well as other related intellectual property developed by the sole inventor, Melinda B. Chu, M.D., M.B.A. The concepts presented herein are intended to provide scientific background, rationale, and illustrative embodiments and should not be interpreted as limiting the scope of any pending or future patent applications.