GC×GC-TOFMS metabolomics and exposomics for cannabis exposures (Ryland T. Giebelhaus, MDCW 2025)

🎤 Presenter: Ryland T. Giebelhaus (University of Alberta, Edmonton, Canada)

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💡 Book in your calendar: 17th Multidimensional Chromatography Workshop (MDCW) 13 - 15. January 2026

Abstract

With the 2018 legalization of cannabis in Canada, there is growing concern surrounding the impacts of fetal and neonatal cannabis exposures. The long-term outcomes of early cannabis exposures are still unknown; however, some teens who use cannabis have permanent brain changes and increased risk of mental health problems. Much less is known about second-hand cannabis exposure and whether this exposes children to biologically significant levels of cannabis.

Our interdisciplinary study follows mothers from early pregnancy until their babies are 18 months old. Mothers complete surveys on cannabis and tobacco use, second-hand exposure, demographics, health, and home environment. We are collecting urine from the mothers and infants, and breastmilk shortly after birth and 3 months postpartum. Additionally, we are utilizing wristband-based passive samplers to profile the exposomes of participants. We are employing comprehensive two-dimensional gas-chromatography time-of-flight mass spectrometry (GC×GC-TOFMS) for the untargeted metabolomics of urine and breastmilk samples to determine how cannabis is metabolized, identify cannabis metabolites and biomarkers of other exposure events including tobacco smoke, and for exposome profiling.

Here, we present preliminary results from the initial batch of urine samples we analyzed from the first 100 participants enrolled. In this cohort, 72.8% reported some level of cannabis exposure (first or second-hand) in the prior 12 months, with 9.7% reporting daily or weekly use. In urine, we identified a number of exposure markers, including cannabinoid metabolites, dietary markers, and pharmaceutical metabolites. This research provides valuable information to assist families in making informed choices about cannabis use during pregnancy.