Abstract View
Atmospheric Transport of Pesticides and PFAS through Dry and Wet Deposition
Eve Painter, JENNIFER FAUST, College of Wooster
Abstract Number: 694
Working Group: Remote and Regional Atmospheric Aerosol
Abstract
Pesticides are a unique class of chemical contaminants that humans deliberately introduce to the environment in large quantities. Once applied to crops, pesticides enter the atmosphere through spray drift, volatilization, and wind erosion of soil. Many pesticides favorably partition to aerosol particles and undergo atmospheric transport. Pesticides can then return to Earth’s surface through dry and wet deposition. Our objective is to identify and quantify pesticides in particulate matter, rainwater, and snow samples collected in the central United States in order to explore spatial and temporal trends in pesticide deposition fluxes. A three-stage impactor is used to collect particles down to a size cutoff of 0.05 µm. Samples are extracted and then analyzed by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) to identify unknown pesticides through suspect screening and non-targeted analysis. Precipitation samples are also collected at the same sites, extracted and concentrated by solid-phase extraction (SPE), and analyzed by high-resolution mass spectrometry. Preliminary results have shown that the insecticide diethyltoluamide (DEET) and the herbicides atrazine and simazine are present in rainwater collected in Ohio between 2018-2021. Future work will use air mass back trajectories and statistical testing to assess whether local or regional sources dominate pesticide deposition fluxes.