Calibration of Passive Sampling Eyewear to Assess Inhalation Exposure

Abstract Calibrated wearable passive air samplers are critical tools for accessibly quantifying individualized and population exposures to airborne pollution, a leading cause of chronic disease. Our lab recently introduced passive sampling eyewear (PSE) to address gaps in tools tailored for measuring and mitigating risks from inhalation exposure. The PSE, like most existing designs of wearable samplers, is largely uncalibrated. An exception is the polydimethylsiloxane (PDMS) brooch, and mini-polyurethane foam (PUF) samplers, which have been calibrated for only 27 compounds. Here, we calibrate PSE against active air samplers codeployed in both stationary and wearable forms in office and home environments to capture a wide range of exposure scenarios. We report sampling rates (RS) and inhalation exposure for over 200 features covering diverse physical-chemical properties measured using the Orbitrap gas chromatography coupled to mass spectrometry (GC–MS) system in both targeted and nontargeted modes. RS were 0.70 ± 0.62 m3 day–1 dm–2 for stationary and 0.85 ± 0.68 m3 day–1 dm–2 for wearable deployments, with no significant difference (p = 0.06) between the deployment types. Wearable calibration captured higher RS and variability, as expected for personal sampling, because participants’ movement and daily activity can alter airflow and disrupt the stagnant air-boundary layer around the sampler. In terms of analysis mode, RS derived from targeted and nontargeted analysis (NTA) were reasonably comparable for a given compound, differing by ∼1.5-fold, boosting confidence in using NTA approaches for expanding databases of RS. Applying the wearable RS, the profiles and levels of inhalation exposure varied widely between participants when at home versus in offices, reflecting differences in exposure sources and dynamics between the two environments. Overall, the findings from both the calibration and field studies represent a significant step toward quantitatively assessing inhalation exposure using PSE.