An Exposure-Aligned Analytical Domain Framework for Interpreting Mycotoxin Measurements Across Airborne, Dust, and Surface Media in Indoor Environments

Environmental measurements obtained from air, dust, and surfaces are frequently interpreted as interchangeable indicators of exposure, despite each method operating within an analytically distinct domain defined by unique physical properties, temporal integration, and exposure relevance. This misalignment contributes to the widespread perception of conflicting or inconclusive results in environmental fungal and mycotoxin investigations, even when each method is analytically valid within its intended domain.

This manuscript formalizes a domain-based interpretive framework that defines the scope, boundaries, and alignment logic for interpreting mycotoxin measurements. Airborne sampling is situated within the inhalation-relevant Airborne Domain, governed by the persistence, transport, and respiratory deposition behavior of fine and ultrafine particles. Dust-based methods are positioned within the Dust Reservoir Domain, representing time-integrated accumulation on surfaces and reflecting historical deposition. Surface sampling is treated as a localized Surface Domain that supports verification of cleaning efficacy or targeted contamination but does not directly reflect inhalation exposure.

Drawing on concepts from aerosol physics, microenvironmental airflow, particle-phase partitioning, and interfacial chemistry, the framework defines principles of domain non-equivalence, temporal mismatch, and exposure alignment. These principles clarify why divergence among spore counts, dust-based measurements, and airborne mycotoxin results is expected and mechanistically supported.

This work does not define exposure thresholds or compliance standards but provides a structured interpretive model to support defensible environmental assessment and proportionate interpretation of environmental measurements across analytically distinct domains.