Enabling Quantitative Analysis of Surface Small Molecules for Exposomics and Behavioral Studies

Abstract

Workplace chemical exposures are a major source of occupational injury. Although over half of these are skin exposures, exposomics research often focuses on chemical levels in the air or in worker biofluids such as blood and urine. Until now, one limitation has been the lack of methods to quantitatively measure surface chemical transfer. Outside the realm of harmful chemicals, the small molecules we leave behind on surfaces can also reveal important aspects of human behavior. In this study, we developed a swab-based quantitative approach to determine small molecule concentrations across common surfaces. We demonstrate its utility using one drug, cyclobenzaprine, on metal surfaces, and two human-derived metabolites, carnitine and phenylacetylglutamine, on four common surfaces: linoleum flooring, plastified laboratory workbench, metal, and Plexiglas. We observed peak areas proportional to surface analyte concentrations at 45 min and 1 week after deposition, enabling quantification of molecule abundance on workplace built environment surfaces. In contrast, this method was unsuitable for analysis of oleanolic acid, for which we did not observe a strong linear proportional relationship following swab-based recovery from surfaces. Overall, this method paves the way for future quantitative exposomics studies in analyte-specific and surface-specific frameworks.

Persistent Biofluid Small-Molecule Alterations Induced by Trypanosoma cruzi Infection Are Not Restored by Parasite Elimination

“…Targeted data processing was performed using Skyline version 20.1.0.155, with parameters similar to those reported in Katemauswa et al (Table ). Missing values were input as the lowest reported peak area across all samples.…”

“…66 The cotton swab was placed into a small eppendorf with the bottom cut out and then placed into a large eppendorf. Both eppendorfs with the swab were centrifuged for saliva retrieval (similar to methods optimized in Katemauswa et al 67 ). Urine was collected by placing mice in a single cage until urination.…”